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Virginia Commonwealth University
1.
Xu, Leyuan.
Semi-Interpenetrating Network Gelatin Fiber Sca old for Oral Mucosal Delivery of Insulin.
Degree: MS, Biomedical Engineering, 2013, Virginia Commonwealth University
URL: https://doi.org/10.25772/54XE-B820 
;
https://scholarscompass.vcu.edu/etd/3191
► Common therapy for diabetes mellitus is subcutaneous administration of insulin that is subject to serious disadvantages, such as patient noncompliance and occasional hypoglycemia. Hence, oral…
(more)
▼ Common therapy for diabetes mellitus is subcutaneous administration of insulin that is
subject to serious disadvantages, such as patient noncompliance and occasional hypoglycemia. Hence, oral administration of insulin could be more convenient and serve as a desired route. However, oral administration of insulin is severely limited by the low bioavailability of insulin through the gastrointestinal tract. In this study, a semi-interpenetrating network gelatin fiber scaffold (sIPN GF) was fabricated for oral mucosal delivery of insulin as an alternative route. This sIPN GF was engineered from an electrospun gelatin fiber scaffold (GF), which was further crosslinked with polyethylene glycol diacrylate (PEG-DA) to enhance its stability. Within the crosslinking process, eosin Y served as a
photoinitiator, and the ratio of PEG-DA to eosin Y was optimized with respect to cytocompatibility and degradation rate. The results showed that the fabricated scaffold morphology, mechanical properties, and degradation rate were significantly enhanced after the crosslinking process. This optimized formulation was used to fabricate sIPN gelatin-co-insulin fiber scaffold (sIPN GIF). Enzyme-linked immunosorbent assay (ELISA) was used to monitor the insulin releasing kinetics of sIPN GIF. Western blot analysis showed that sIPN GIF activated intracellular AKT phosphorylation in a releasing time-dependant manner. Oil red O staining confirmed the released insulin was able to induce 3T3-L1 preadipocyte differentiation. The permeability of insulin from sIPN GIF was determined on the order of 10^-7 cm/s using a vertical Franz diffusion cell system mounted with porcine buccal mucosa. These findings suggest that sIPN GIF holds a great potential for oral mucosal delivery of insulin.
Advisors/Committee Members: Hu Yang.
Subjects/Keywords: Drug delivery; insulin; photoinitiator; scaffold; Biomedical Engineering and Bioengineering; Engineering
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APA (6th Edition):
Xu, L. (2013). Semi-Interpenetrating Network Gelatin Fiber Sca old for Oral Mucosal Delivery of Insulin. (Thesis). Virginia Commonwealth University. Retrieved from https://doi.org/10.25772/54XE-B820 ; https://scholarscompass.vcu.edu/etd/3191
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Xu, Leyuan. “Semi-Interpenetrating Network Gelatin Fiber Sca old for Oral Mucosal Delivery of Insulin.” 2013. Thesis, Virginia Commonwealth University. Accessed March 05, 2021.
https://doi.org/10.25772/54XE-B820 ; https://scholarscompass.vcu.edu/etd/3191.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Xu, Leyuan. “Semi-Interpenetrating Network Gelatin Fiber Sca old for Oral Mucosal Delivery of Insulin.” 2013. Web. 05 Mar 2021.
Vancouver:
Xu L. Semi-Interpenetrating Network Gelatin Fiber Sca old for Oral Mucosal Delivery of Insulin. [Internet] [Thesis]. Virginia Commonwealth University; 2013. [cited 2021 Mar 05].
Available from: https://doi.org/10.25772/54XE-B820 ; https://scholarscompass.vcu.edu/etd/3191.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Xu L. Semi-Interpenetrating Network Gelatin Fiber Sca old for Oral Mucosal Delivery of Insulin. [Thesis]. Virginia Commonwealth University; 2013. Available from: https://doi.org/10.25772/54XE-B820 ; https://scholarscompass.vcu.edu/etd/3191
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Pretoria
2.
[No author].
Photoinitiated cyanoacrylates for fast underwater
bonding
.
Degree: 2011, University of Pretoria
URL: http://upetd.up.ac.za/thesis/available/etd-10212009-181354/
► Strong underwater bonds between polycarbonate sheet and various other substrates were achieved using ethyl 2-cyanoacrylate gel cured with an anionic photoinitiator (dibenzoylferrocene). The gel reacts…
(more)
▼ Strong underwater bonds between polycarbonate sheet
and various other substrates were achieved using ethyl
2-cyanoacrylate gel cured with an anionic
photoinitiator
(dibenzoylferrocene). The gel reacts quickly with water on contact
and forms a protective polyethyl cyanoacrylate (PECA) skin. This
provides a diffusion barrier that protects the inner monomer from
further reaction with or polymerisation by water (hydroxide ions).
The PECA skin is, however, permeable to water and the inner monomer
slowly reacts as water diffuses through the PECA skin. The
application procedure for this adhesive is critical because of the
fast reaction with water. The adhesive should be applied at the
centre of the bond area in such a way as to cover the smallest
exposed surface area and that it should not be spread out over the
entire surface area. The PECA skin will rupture when the substrates
are pressed together, exposing unreacted monomer to the fresh new
surface between the two substrates. The adhesive displaces water as
it propagates towards the joint edges. In this way it is able to
form a strong underwater bond. Without a
photoinitiator, ethyl
cyanoacrylate adhesives will form strong bonds to smooth underwater
surfaces. The addition of a
photoinitiator (dibenzoylferrocene),
however, increases the rate at which the bond strength develops.
Photo differential scanning calorimetric (photo-DSC) analysis was
used to determine the optimum
photoinitiator concentration. A
concentration of between 0.3% (m/m) and 0.1% (m/m) was found to be
optimum for adhesive films between 0.5 and 1.2 mm thick.
Epoxy-based underwater adhesives have the disadvantage that the
cure rate is very slow at low water temperatures. In contrast, the
current system features a negative temperature dependence.
Therefore, the curing rate is faster at lower water temperatures,
making it highly suitable for very cold environmental conditions.
The underwater bonding properties of cyanoacrylate adhesive were
measured on a wide range of metallic and non-metallic materials.
Bond strengths ranged from 1 to 5 MPa respectively. Bond strength
(0.2 mm film thickness) develops in a very short time (less than a
minute) using a 5 mW/cm2 blue LED light source as trigger for the
photo initiator. Water temperatures between 1.5 and 40 °C did not
influence the ultimate bond strength achieved following 50 seconds
of illumination. The reduction in bond strength due to the ethyl
cyanoacrylates reacting with water was measured in artificial sea
water and potable water. A 20% reduction in bond strength was found
after 10 minutes of water exposure. The underwater bond should
therefore be made as soon as possible following exposure to water.
Bond ageing studies on both steel and polycarbonate showed an
initial decrease in bond strength (during the first 50 hours);
thereafter the bond strength stabilises.
Advisors/Committee Members: Prof W W Focke (advisor).
Subjects/Keywords: Ethyl cyanoacrylates;
Dibenzoylferrocene;
Photoinitiator;
Underwater bonding;
Photo differential scanning calorimetry;
Polycarbonate;
Bond ageing;
Underwater application;
Shear bond strength;
Illumination;
UCTD
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APA (6th Edition):
author], [. (2011). Photoinitiated cyanoacrylates for fast underwater
bonding
. (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-10212009-181354/
Chicago Manual of Style (16th Edition):
author], [No. “Photoinitiated cyanoacrylates for fast underwater
bonding
.” 2011. Masters Thesis, University of Pretoria. Accessed March 05, 2021.
http://upetd.up.ac.za/thesis/available/etd-10212009-181354/.
MLA Handbook (7th Edition):
author], [No. “Photoinitiated cyanoacrylates for fast underwater
bonding
.” 2011. Web. 05 Mar 2021.
Vancouver:
author] [. Photoinitiated cyanoacrylates for fast underwater
bonding
. [Internet] [Masters thesis]. University of Pretoria; 2011. [cited 2021 Mar 05].
Available from: http://upetd.up.ac.za/thesis/available/etd-10212009-181354/.
Council of Science Editors:
author] [. Photoinitiated cyanoacrylates for fast underwater
bonding
. [Masters Thesis]. University of Pretoria; 2011. Available from: http://upetd.up.ac.za/thesis/available/etd-10212009-181354/
3.
Amaral, Aline Bassi Denis Bordini do.
Avaliação do grau de conversão monomérica, parâmetros de cinética de polimerização e determinação de monômeros residuais em resinas experimentais.
Degree: PhD, Química Analítica e Inorgânica, 2012, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/75/75135/tde-25072012-090212/
;
► Este estudo teve como objetivo investigar múltiplos aspectos relacionados a polimerização da resina composta como: o grau de conversão monomérica (GC), parâmetros da cinética de…
(more)
▼ Este estudo teve como objetivo investigar múltiplos aspectos relacionados a polimerização da resina composta como: o grau de conversão monomérica (GC), parâmetros da cinética de polimerização e a determinação de monômeros residuais TEGDMA e BisGMA, além de avaliar o desempenho de aparelhos fotoativadores. As resinas compostas experimentais foram manipuladas variando-se os fotoiniciadores R1-) canforoquinona/amina, R2-) PPD/amina, R3-) PPD + canforoquinona/amina) e foram utilizados dois aparelhos para a fotoativação (I-) lâmpada halógena (Demetron LC/ SDS Kerr-USA) e II-) LED (Poly 600/Kavo-Brasil) ambos com 600 mW cm-2, por 40 s. O GC após 300 s e os parâmetros de cinética como taxa máxima de conversão (Rpmáx), tempo em que ocorreu a taxa máxima de polimerização (tmáx) e a conversão quando ocorreu a Rpmáx, foram determinados por meio de espectroscopia de absorção no infravermelho em tempo real (RT-FTIR), Os espectros foram coletados dos espécimes (n=5) no modo cinética, durante 305 s, entre 1680 e 1550 cm-1. As 5 primeiras varreduras coletadas serviram para fornecer o espectro de absorção da resina não polimerizada (utilizado no cálculo do GC). Na 6º varredura, o fotoativador foi ligado (por 40 segundos) enquanto o espectro continuava a ser coletado até 300 s após a ativação da luz. A presença de monômeros residuais (TEGDMA e BisGMA) foi avaliada por meio da cromatografia líquida de alta eficiência (HPLC), sendo que os espécimes (n=6) foram imersos em acetonitrila (5 mL-24 h) com agitação mecânica, o método desenvolvido utilizou: HPLC, coluna C18, fase móvel A: água com trietilamina (0,05%) acidificada com ácido acético (pH 4) e B: acetonitrila, modo de eluição com gradiente (40-85%-17 min/ 55°C), fluxo de 1 mL min-1, detector UV em 210 nm, injeção de 20 µL. Em relação aos resultados de GC após 300 s os maiores valores foram para a resina R1 tanto fotoativada com LED (65,90% ±1,81) quanto com a lâmpada halógena (64,40% ±0,83), e os menores valores encontrados foram quando a resina R2 foi fotoativada pelo LED (35,64% ±1,73) e a única resina que apresentou diferenças significantes em relação as fontes de luz foi a R2. Os valores da Rpmáx diminuíram nas resinas que apresentavam o fotoiniciador PPD. O tempo de ocorrência da taxa máxima de conversão (tmáx) aconteceu mais rapidamente para a resina com CQ. Todas as resinas apresentaram valores de grau de conversão similares no tmáx. Em relação aos resultados de HPLC, a quantidade de monômeros extraídos (M/M%) variou de 1,98% ±0,16 à 3,34% ±0,07 para os monômeros TEGDMA e de 3,57% ±0,30 à 7,57% ±0,40 para os monômeros BisGMA. A resina R2 apresentou a maior quantidade de monômeros residuais quando fotoativada com ambas as fontes, principalmente quando fotoativada com o LED. As resinas R1 e R3 obtiveram comportamento parecidos para ambos fotoativadores. Conclui-se que a resina R3 pode ser uma boa opção, pois quando comparada com a resina R1 apresentou vantagens como: redução na…
Advisors/Committee Members: Plepis, Ana Maria de Guzzi.
Subjects/Keywords: cinética de polimerização; degree of conversion; fotoiniciador; grau de conversão; monômeros residuais; photoinitiator; polymerization kinetics; residual monomers; resin; resina
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APA ·
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CSE |
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APA (6th Edition):
Amaral, A. B. D. B. d. (2012). Avaliação do grau de conversão monomérica, parâmetros de cinética de polimerização e determinação de monômeros residuais em resinas experimentais. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/75/75135/tde-25072012-090212/ ;
Chicago Manual of Style (16th Edition):
Amaral, Aline Bassi Denis Bordini do. “Avaliação do grau de conversão monomérica, parâmetros de cinética de polimerização e determinação de monômeros residuais em resinas experimentais.” 2012. Doctoral Dissertation, University of São Paulo. Accessed March 05, 2021.
http://www.teses.usp.br/teses/disponiveis/75/75135/tde-25072012-090212/ ;.
MLA Handbook (7th Edition):
Amaral, Aline Bassi Denis Bordini do. “Avaliação do grau de conversão monomérica, parâmetros de cinética de polimerização e determinação de monômeros residuais em resinas experimentais.” 2012. Web. 05 Mar 2021.
Vancouver:
Amaral ABDBd. Avaliação do grau de conversão monomérica, parâmetros de cinética de polimerização e determinação de monômeros residuais em resinas experimentais. [Internet] [Doctoral dissertation]. University of São Paulo; 2012. [cited 2021 Mar 05].
Available from: http://www.teses.usp.br/teses/disponiveis/75/75135/tde-25072012-090212/ ;.
Council of Science Editors:
Amaral ABDBd. Avaliação do grau de conversão monomérica, parâmetros de cinética de polimerização e determinação de monômeros residuais em resinas experimentais. [Doctoral Dissertation]. University of São Paulo; 2012. Available from: http://www.teses.usp.br/teses/disponiveis/75/75135/tde-25072012-090212/ ;
University of Pretoria
4.
Cloete, William
Edward.
Photoinitiated
cyanoacrylates for fast underwater bonding.
Degree: Chemical Engineering, 2011, University of Pretoria
URL: http://hdl.handle.net/2263/28899
► Strong underwater bonds between polycarbonate sheet and various other substrates were achieved using ethyl 2-cyanoacrylate gel cured with an anionic photoinitiator (dibenzoylferrocene). The gel reacts…
(more)
▼ Strong underwater bonds between polycarbonate sheet and
various other substrates were achieved using ethyl 2-cyanoacrylate
gel cured with an anionic
photoinitiator (dibenzoylferrocene). The
gel reacts quickly with water on contact and forms a protective
polyethyl cyanoacrylate (PECA) skin. This provides a diffusion
barrier that protects the inner monomer from further reaction with
or polymerisation by water (hydroxide ions). The PECA skin is,
however, permeable to water and the inner monomer slowly reacts as
water diffuses through the PECA skin. The application procedure for
this adhesive is critical because of the fast reaction with water.
The adhesive should be applied at the centre of the bond area in
such a way as to cover the smallest exposed surface area and that
it should not be spread out over the entire surface area. The PECA
skin will rupture when the substrates are pressed together,
exposing unreacted monomer to the fresh new surface between the two
substrates. The adhesive displaces water as it propagates towards
the joint edges. In this way it is able to form a strong underwater
bond. Without a
photoinitiator, ethyl cyanoacrylate adhesives will
form strong bonds to smooth underwater surfaces. The addition of a
photoinitiator (dibenzoylferrocene), however, increases the rate at
which the bond strength develops. Photo differential scanning
calorimetric (photo-DSC) analysis was used to determine the optimum
photoinitiator concentration. A concentration of between 0.3% (m/m)
and 0.1% (m/m) was found to be optimum for adhesive films between
0.5 and 1.2 mm thick. Epoxy-based underwater adhesives have the
disadvantage that the cure rate is very slow at low water
temperatures. In contrast, the current system features a negative
temperature dependence. Therefore, the curing rate is faster at
lower water temperatures, making it highly suitable for very cold
environmental conditions. The underwater bonding properties of
cyanoacrylate adhesive were measured on a wide range of metallic
and non-metallic materials. Bond strengths ranged from 1 to 5 MPa
respectively. Bond strength (0.2 mm film thickness) develops in a
very short time (less than a minute) using a 5 mW/cm2 blue LED
light source as trigger for the photo initiator. Water temperatures
between 1.5 and 40 °C did not influence the ultimate bond strength
achieved following 50 seconds of illumination. The reduction in
bond strength due to the ethyl cyanoacrylates reacting with water
was measured in artificial sea water and potable water. A 20%
reduction in bond strength was found after 10 minutes of water
exposure. The underwater bond should therefore be made as soon as
possible following exposure to water. Bond ageing studies on both
steel and polycarbonate showed an initial decrease in bond strength
(during the first 50 hours); thereafter the bond strength
stabilises.
Advisors/Committee Members: Prof W W Focke (advisor).
Subjects/Keywords: Ethyl
cyanoacrylates;
Dibenzoylferrocene;
Photoinitiator; Underwater
bonding; Photo
differential scanning calorimetry;
Polycarbonate; Bond
ageing; Underwater
application; Shear bond
strength;
Illumination;
UCTD
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APA ·
Chicago ·
MLA ·
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CSE |
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Manager
APA (6th Edition):
Cloete, W. (2011). Photoinitiated
cyanoacrylates for fast underwater bonding. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/28899
Chicago Manual of Style (16th Edition):
Cloete, William. “Photoinitiated
cyanoacrylates for fast underwater bonding.” 2011. Masters Thesis, University of Pretoria. Accessed March 05, 2021.
http://hdl.handle.net/2263/28899.
MLA Handbook (7th Edition):
Cloete, William. “Photoinitiated
cyanoacrylates for fast underwater bonding.” 2011. Web. 05 Mar 2021.
Vancouver:
Cloete W. Photoinitiated
cyanoacrylates for fast underwater bonding. [Internet] [Masters thesis]. University of Pretoria; 2011. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2263/28899.
Council of Science Editors:
Cloete W. Photoinitiated
cyanoacrylates for fast underwater bonding. [Masters Thesis]. University of Pretoria; 2011. Available from: http://hdl.handle.net/2263/28899
Brno University of Technology
5.
Rudická, Andrea.
Studium kinetiky fotochemických reakcí v tenké tištěné polymerní vrstvě: Kinetic study of photochemical reactions in thin printed layer.
Degree: 2020, Brno University of Technology
URL: http://hdl.handle.net/11012/190953
► This diploma thesis deals with a study of kinetics of photochemical reactions in a thin printed polymer layer. The experimental part deals with the composition…
(more)
▼ This diploma thesis deals with a study of kinetics of photochemical reactions in a thin printed polymer layer. The experimental part deals with the composition preparation and layers coating. The prepared layers were exposed and subsequently studied for their colour response to the light. The aim of this work was to prepare a photosensitive layer with a significant colour change between individual doses of radiation, to improve the mechanical resistance of the layers, to adjust the sensitivity of the compositions to UVB radiation and to study the kinetics of the photochemical reaction used.
Advisors/Committee Members: Veselý, Michal (advisor), Čeppan,, Michal (referee).
Subjects/Keywords: Fotochemie; fotoiniciátor; UV záření; UVB záření; tenké vrstvy; Photochemistry; photoinitiator; UV radiation; UVB radiation; thin layers
Record Details
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APA ·
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APA (6th Edition):
Rudická, A. (2020). Studium kinetiky fotochemických reakcí v tenké tištěné polymerní vrstvě: Kinetic study of photochemical reactions in thin printed layer. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/190953
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Rudická, Andrea. “Studium kinetiky fotochemických reakcí v tenké tištěné polymerní vrstvě: Kinetic study of photochemical reactions in thin printed layer.” 2020. Thesis, Brno University of Technology. Accessed March 05, 2021.
http://hdl.handle.net/11012/190953.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rudická, Andrea. “Studium kinetiky fotochemických reakcí v tenké tištěné polymerní vrstvě: Kinetic study of photochemical reactions in thin printed layer.” 2020. Web. 05 Mar 2021.
Vancouver:
Rudická A. Studium kinetiky fotochemických reakcí v tenké tištěné polymerní vrstvě: Kinetic study of photochemical reactions in thin printed layer. [Internet] [Thesis]. Brno University of Technology; 2020. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/11012/190953.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rudická A. Studium kinetiky fotochemických reakcí v tenké tištěné polymerní vrstvě: Kinetic study of photochemical reactions in thin printed layer. [Thesis]. Brno University of Technology; 2020. Available from: http://hdl.handle.net/11012/190953
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
6.
Di Stefano, Luciano Héctor.
Development of New Photoiniator Systems for Polymerization with Visible Light : Développement de Nouveaux Systèmes Photomamorceurs de Polymérisation sous Lumière visible.
Degree: Docteur es, Chimie Physique, 2015, Mulhouse
URL: http://www.theses.fr/2015MULH9439
► La photopolymérisation est une technologie qui gagne de plus en plus d’importance de par ses nombreuses applications et ses énormes avantages par rapport à la…
(more)
▼ La photopolymérisation est une technologie qui gagne de plus en plus d’importance de par ses nombreuses applications et ses énormes avantages par rapport à la polymérisation thermique tels que le respect de l’environnement, des coûts économiques maitrisés car la technologie est mise en œuvre à température ambiante et ne requiert qu’une faible consommation d'énergie. De plus, elle n'utilise pas ou très peu de solvants, d'où la réduction d’émission de produits polluants. Le processus de polymérisation photochimique présente également l’avantage d’être très rapide : en effet les réactions de photopolymérisation sont souvent rapides voire même quasi instantanées. De plus le procédé de polymérisation devient photolatent : la polymérisation impliquant les formulations actives seulement en présence de lumière, la réaction peut être déclenchée « quasi à la demande ». Ce processus chimique nécessite des composants nommés « photoamorceurs », lesquels absorbent la lumière et produisent le démarrage de la réaction de polymérisation. En particulier, le développement de systèmes photoamorceurs capables d’absorber de la lumière visible a un intérêt croissant pour différentes applications industrielles, notamment l’holographie. Dans la cadre de cette thèse, des diverses systèmes photoamorceurs contenant un colorant et un ou deux co-amorceurs, qui après réaction avec les états excités des colorants génèrent les radicaux actifs, ont été étudiés, depuis leurs propriétés photophysiques fondamentales et moléculaires, jusqu’aux applications et performances pour la polymérisation des résines acrylates. Cette thèse est articulée autour de six chapitres. Dans le premier chapitre une introduction et une étude bibliographique des différents systèmes photoamorceurs développés ces dernières années sont présentées et comparés. Les chapitres deux et trois sont consacrés à l’étude des propriétés photochimiques et photophysiques réalisés sur des photoamorceurs absorbant de la lumière ultraviolette et visible respectivement. Les techniques utilisés dans ces chapitres incluent, mais ne sont pas limités à, la spectroscopie d’absorption UV-Vis stationnaire, la fluorescence, la photolyse éclaire (LFP), la fluorescence résolue en temps par comptage de photon unique (TC-SPC), la spectroscopie ultrarapide nanoseconde et femtoseconde, la spectroscopie de résonance paramagnétique électronique (EPR), entre autres. Le chapitre deux porte sur l’étude de la photophysique d’un colorant de type cyanine : l’astrazone Orange R (AO R). La photophysique de ce colorant n’est pas connue et une étude exhaustive a été menée avec des spectroscopies ultra rapides (femtoseconde) ainsi que par modélisation moléculaire. Malgré sa photophysique compliquée ce colorant, fonctionne comme un photoamorceur très efficace dans la région bleue du spectre électromagnétique. Les chapitres suivants forment une deuxième partie de la thèse dédiée à l’étude des mécanismes d’amorçage de photopolymérisation, dont le chapitre quatre aborde le cas d’irradiation le plus « traditionnel », qui est…
Advisors/Committee Members: Allonas, Xavier (thesis director).
Subjects/Keywords: Photopolymérisation; Mécanisme; Photoamorceur; Photocycle; Polymérisation Radicalaire; Astrazone Orange; Modélisation; Polyacrylates; Photopolymerization; Mechanism; Photoinitiator; Photocycle; Radical Polymerization; Astrazone Orange; Modelization; Polyacrylate
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APA ·
Chicago ·
MLA ·
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CSE |
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APA (6th Edition):
Di Stefano, L. H. (2015). Development of New Photoiniator Systems for Polymerization with Visible Light : Développement de Nouveaux Systèmes Photomamorceurs de Polymérisation sous Lumière visible. (Doctoral Dissertation). Mulhouse. Retrieved from http://www.theses.fr/2015MULH9439
Chicago Manual of Style (16th Edition):
Di Stefano, Luciano Héctor. “Development of New Photoiniator Systems for Polymerization with Visible Light : Développement de Nouveaux Systèmes Photomamorceurs de Polymérisation sous Lumière visible.” 2015. Doctoral Dissertation, Mulhouse. Accessed March 05, 2021.
http://www.theses.fr/2015MULH9439.
MLA Handbook (7th Edition):
Di Stefano, Luciano Héctor. “Development of New Photoiniator Systems for Polymerization with Visible Light : Développement de Nouveaux Systèmes Photomamorceurs de Polymérisation sous Lumière visible.” 2015. Web. 05 Mar 2021.
Vancouver:
Di Stefano LH. Development of New Photoiniator Systems for Polymerization with Visible Light : Développement de Nouveaux Systèmes Photomamorceurs de Polymérisation sous Lumière visible. [Internet] [Doctoral dissertation]. Mulhouse; 2015. [cited 2021 Mar 05].
Available from: http://www.theses.fr/2015MULH9439.
Council of Science Editors:
Di Stefano LH. Development of New Photoiniator Systems for Polymerization with Visible Light : Développement de Nouveaux Systèmes Photomamorceurs de Polymérisation sous Lumière visible. [Doctoral Dissertation]. Mulhouse; 2015. Available from: http://www.theses.fr/2015MULH9439
7.
Leonardo Freitas da Silveira.
Efeito do tipo de fonte de luz sobre propriedades físicas de cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores.
Degree: 2013, Universidade de Taubaté
URL: http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=590
► Cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores apresentaram propriedades físicas semelhantes ou superiores a cimentos resinosos convencionais sob efeito de diferentes tipos de fonte de…
(more)
▼ Cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores apresentaram propriedades físicas semelhantes ou superiores a cimentos resinosos convencionais sob efeito de diferentes tipos de fonte de luz. Objetivo: Analisar o espectro de diferentes fontes de luz e sistemas fotoiniciadores e sua influência nas propriedades físicas de cimentos resinosos quando ativados, através de um anteparo cerâmico, por fontes de luz halógena e LED. Metodologia: Cimentos resinosos experimentais contendo uma mistura de BisGMA, TEGDMA (50wt%) e partículas de carga silanizadas (65wt%), foram preparados com o uso dos fotoiniciadores Canforoquinona (CQ), Fenil Propanodiona (PPD) e Óxido bis-alquil fosfínico (BAPO) de forma isolada e combinados. Os co-iniciadores utilizados foram Difenil Iodônio (DFIHFP) e a amina terciária DMAEMA. As fontes de luz utilizadas foram: lâmpada halógena (XL 2500) e duas fontes de diodo emissor de luz - LED (FreeLigth 2 e Bluephase). Um anteparo cerâmico (IPS e.max Press) apresentando 13,0mm x 1,0mm de espessura foi utilizado durante os testes. Amostras com 7,0mm x 2,0mm x 1,0mm foram confeccionadas (n=360). A avaliação do Grau de Conversão (GC) dos cimentos experimentais foi realizada por Espectroscopia de Infravermelho Transformada de Fourier (FTIR), sendo em seguida submetidas ao teste de resistência à mini-flexão, módulo flexural e microdureza Knoop. Os resultados obtidos em todos os testes foram submetidos à análise de variância dois fatores - ANOVA e teste de Tukey (5%). Resultados: A associação do DFIHFP aos fotoiniciadores aumentou as propriedades avaliadas de todos os cimentos experimentais independente da fonte de luz (FL) utilizada. O fotoiniciador BAPO apresentou resultados superiores ou iguais estatisticamente em comparação ao grupo controle (CQ/amina), independente da FL utilizada. Conclusão: A utilização de sistemas iniciadores e co-iniciadores alternativos possibilita a obtenção de propriedades superiores ou iguais ao sistema convencional, tornando-se um sistema promissor para atuar de forma isolada ou associada.
Resin cements containing different experimental photoinitiators systems present physical properties similar to or better than conventional resin cements under the effect of different types of light source. Objective: To analyze the spectrum of different light sources and systems photoinitiators and their influence on physical properties of resin cements when activated through a bulkhead ceramic, halogen light sources and LED. Methodology: experimental resin cements containing a mixture of BisGMA, TEGDMA (50wt%) and silanized filler particles (65wt%) were prepared with the use of photoinitiators camphorquinone (CQ), phenyl oxide bis-propanedione (PPD) and alkyl phosphinic (BAPO) separately and combined. The primers used were co-diphenyl iodonium (DFIHFP) tertiary amine and DMAEMA. The light sources used were: halogen lamp (XL 2500) and two sources of light emitting diode - LED (FreeLigth bluephase and 2). A ceramic shield (IPS e.max Press) having 13.0mm x 1.0mm thick…
Advisors/Committee Members: William Cunha Brandt, Priscila Christiane Suzy Liporoni, Anderson Pinheiro de Freitas.
Subjects/Keywords: fotoiniciador; canforoquinona; microdureza knoop; fonte de luz; resin cement; degree of conversion; photoinitiator; canphorquinone; knoop hardness; cimento resinoso; grau de conversão; light source; ODONTOLOGIA
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APA (6th Edition):
Silveira, L. F. d. (2013). Efeito do tipo de fonte de luz sobre propriedades físicas de cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores. (Thesis). Universidade de Taubaté. Retrieved from http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=590
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Silveira, Leonardo Freitas da. “Efeito do tipo de fonte de luz sobre propriedades físicas de cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores.” 2013. Thesis, Universidade de Taubaté. Accessed March 05, 2021.
http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=590.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Silveira, Leonardo Freitas da. “Efeito do tipo de fonte de luz sobre propriedades físicas de cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores.” 2013. Web. 05 Mar 2021.
Vancouver:
Silveira LFd. Efeito do tipo de fonte de luz sobre propriedades físicas de cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores. [Internet] [Thesis]. Universidade de Taubaté; 2013. [cited 2021 Mar 05].
Available from: http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=590.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Silveira LFd. Efeito do tipo de fonte de luz sobre propriedades físicas de cimentos resinosos experimentais contendo diferentes sistemas fotoiniciadores. [Thesis]. Universidade de Taubaté; 2013. Available from: http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=590
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
8.
Nguyen, Duc Ngoc.
Effects of solvents and comonomers on radiation curing and grafting processes.
Degree: 2002, Western Sydney University
URL: http://handle.uws.edu.au:8081/1959.7/712
► A study has been made on the irradiation induced grafting of MMA to PPE and cellulose subtrates in the presence of various solvents and Irgacure…
(more)
▼ A study has been made on the irradiation induced grafting of MMA to PPE and cellulose subtrates in the presence of various solvents and Irgacure 819
photoinitiator, a new
photoinitiator on the market at the commencement of this project. UV is the main irradiation source used. The grafting yields have been found to vary with parameters such as the subtrate types and thickness, MMA concentration, solvents used, Irgacure 819 concentration and UV doses. For the cellulose subtrate, good grafting yields were obtained only when solvents such as methanol and DMF were used. On the contrary, MMA could graft to PPE with or without solvents, although high grafting yields were achieved in the presence of methanol, DMF and other chlorinated solvents. The solvent effects on the grafting process of MMA to PPE and cellulose subtrates were attributed to the wetting and swelling effects by the solvents as well as the Trommsdorff effect. During the course of this study, a comparison in the performance between Irgacure 819 and other photoinitiators (PIs) was also carried out. A study was made of the UV radiation induced grafting of styrene to PPE subtrate with EP vinyl monomers and vinyl ethers as comonomers. The possibility of spontaneous polymerization of styrene/EP vinyl monomer mixtures under the influence of UV radiation was also investigated. Grafting yields were found to vary with the comonomer types and their concentrations, the presence or absence of solvents and additives such as Irgacure 819
photoinitiator, K185 cationic
photoinitiator, mineral acids and CT complexes. In addition, the composition of grafted subtrates was studied by using the FT-IR spectroscopy technique
Advisors/Committee Members: University of Western Sydney (Host institution), College of Science, Technology and Environment (Host institution), School of Science, Food and Horticulture (Host institution).
Subjects/Keywords: Doctor of Philosophy (PhD); subtrates; photoinitiator; comonomer; radiation; solvents; ethers
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APA (6th Edition):
Nguyen, D. N. (2002). Effects of solvents and comonomers on radiation curing and grafting processes. (Thesis). Western Sydney University. Retrieved from http://handle.uws.edu.au:8081/1959.7/712
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nguyen, Duc Ngoc. “Effects of solvents and comonomers on radiation curing and grafting processes.” 2002. Thesis, Western Sydney University. Accessed March 05, 2021.
http://handle.uws.edu.au:8081/1959.7/712.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nguyen, Duc Ngoc. “Effects of solvents and comonomers on radiation curing and grafting processes.” 2002. Web. 05 Mar 2021.
Vancouver:
Nguyen DN. Effects of solvents and comonomers on radiation curing and grafting processes. [Internet] [Thesis]. Western Sydney University; 2002. [cited 2021 Mar 05].
Available from: http://handle.uws.edu.au:8081/1959.7/712.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nguyen DN. Effects of solvents and comonomers on radiation curing and grafting processes. [Thesis]. Western Sydney University; 2002. Available from: http://handle.uws.edu.au:8081/1959.7/712
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
9.
Christmann, Julien.
Photochimie moléculaire des processus de photopolymérisation : de l'étude mécanistique à la modélisation cinétique : Molecular photochemistry of photopolymerization processes : from mechanistic study to kinetic modeling.
Degree: Docteur es, Chimie physique, 2017, Mulhouse
URL: http://www.theses.fr/2017MULH0698
► Ce travail de thèse aborde l’étude mécanistique de systèmes photoamorceurs complexes et la modélisation cinétique du processus de photopolymérisation. Dans un premier temps, le mécanisme…
(more)
▼ Ce travail de thèse aborde l’étude mécanistique de systèmes photoamorceurs complexes et la modélisation cinétique du processus de photopolymérisation. Dans un premier temps, le mécanisme photochimique d’un système combinant le [Ru(bpy)3]2+ et des agents RAFT pour l’amorçage et le contrôle d’un processus radicalaire a été étudié. Un transfert d’énergie a été clairement démontré, contredisant le mécanisme de transfert d’électron généralement proposé. Un système photoamorceur à 3 composants bicyclique dual ITX/IOD+/RSH a ensuite été considéré pour la synthèse de matériaux hybrides organiques-inorganiques. Sous excitation lumineuse, ce système produit simultanément des radicaux et des protons, permettant d’amorcer, respectivement, des processus de polymérisation radicalaire et sol-gel. Dans un second temps, l’interdépendance entre les cinétiques de photopolymérisation et l’évolution des propriétés du milieu réactionnel a été étudiée par le biais du développement d’un modèle cinétique permettant la simulation de l’intégralité du processus de photopolymérisation. Des systèmes photoamorceurs de complexité croissante ont été inclus afin d’étudier les spécificités de leurs cinétiques. Un système de type I a permis de mettre en évidence les modes de terminaison majoritaires et leur évolution au cours de la synthèse des polymères, tandis que le rôle non négligeable du transfert d’électron inverse a été mis en exergue pour des systèmes photoamorceurs de type II. La fonction d’agent de terminaison d’un photoproduit issu d’un colorant cationique, ainsi que certaines spécificités des systèmes photocycliques à 3 composants, ont été finalement étudiés grâce à la modélisation.
This thesis deals with the mechanistic study of complex photoinitiating systems and the kinetic modeling of the photopolymerization process. In a first time, the photochemical mechanism of a system combining [Ru(bpy)3]2+ and RAFT agents for the initiation and control of a radical process has been studied. An energy transfer has been clearly demonstrated, contradicting the electron transfer mechanism generally proposed. A dual bicyclic three-component photoinitiating system ITX/IOD+/RSH has been considered for the synthesis of organic-inorganic hybrid materials. Under light exposure, this system produces simultaneously radicals and protons, enabling the initiation of a radical polymerization and a sol-gel process, respectively. In a second time, interdependence between photopolymerization kinetics and evolution of the medium’s properties has been studied, through developing a kinetic model for the simulation of the whole photopolymerization process. Photoinitiating systems of growing complexity have been included in order to study specificities of their kinetics. A type-I system has shown major termination modes and their evolution during the polymer synthesis, while the non-negligible role of back electron transfer has been highlighted for type-II photoinitiating systems. Role of terminating agent of a photoproduct based on a cationic dye, as well as some…
Advisors/Committee Members: Allonas, Xavier (thesis director), Croutxé Barghorn, Céline (thesis director), Ley, Christian (thesis director).
Subjects/Keywords: Photochimie moléculaire; Photopolymérisation radicalaire; Etude mécanistique; Modélisation cinétique; Transfert d'électron; Transfert d'énergie; Systèmes photoamorceurs; Molecular photochemistry; Radical photopolymerization; Mechanistic study; Kinetic modeling; Electron transfer; Energy transfer; Photoinitiator systems; 541; 668.9
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APA ·
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APA (6th Edition):
Christmann, J. (2017). Photochimie moléculaire des processus de photopolymérisation : de l'étude mécanistique à la modélisation cinétique : Molecular photochemistry of photopolymerization processes : from mechanistic study to kinetic modeling. (Doctoral Dissertation). Mulhouse. Retrieved from http://www.theses.fr/2017MULH0698
Chicago Manual of Style (16th Edition):
Christmann, Julien. “Photochimie moléculaire des processus de photopolymérisation : de l'étude mécanistique à la modélisation cinétique : Molecular photochemistry of photopolymerization processes : from mechanistic study to kinetic modeling.” 2017. Doctoral Dissertation, Mulhouse. Accessed March 05, 2021.
http://www.theses.fr/2017MULH0698.
MLA Handbook (7th Edition):
Christmann, Julien. “Photochimie moléculaire des processus de photopolymérisation : de l'étude mécanistique à la modélisation cinétique : Molecular photochemistry of photopolymerization processes : from mechanistic study to kinetic modeling.” 2017. Web. 05 Mar 2021.
Vancouver:
Christmann J. Photochimie moléculaire des processus de photopolymérisation : de l'étude mécanistique à la modélisation cinétique : Molecular photochemistry of photopolymerization processes : from mechanistic study to kinetic modeling. [Internet] [Doctoral dissertation]. Mulhouse; 2017. [cited 2021 Mar 05].
Available from: http://www.theses.fr/2017MULH0698.
Council of Science Editors:
Christmann J. Photochimie moléculaire des processus de photopolymérisation : de l'étude mécanistique à la modélisation cinétique : Molecular photochemistry of photopolymerization processes : from mechanistic study to kinetic modeling. [Doctoral Dissertation]. Mulhouse; 2017. Available from: http://www.theses.fr/2017MULH0698
10.
Stocker, Michael Paul.
RAPID Lithography: Photopolymerization Characterization and Initiation Kinetics.
Degree: Chemistry, 2012, University of Maryland
URL: http://hdl.handle.net/1903/13133
► In order to improve upon the resolution of photolithography, a technique that is used to produce features for today's micro and nanodevices, techniques must move…
(more)
▼ In order to improve upon the resolution of photolithography, a technique that is used to produce features for today's micro and nanodevices, techniques must move beyond e-beam and deep-UV sources. Multiphoton absorption polymerization (MAP) uses near-infrared light for the creation of complex, three-dimensional features on the sub-100 nm scale. The resolution of MAP can be enhanced further using a two-beam technique called resolution augmentation through photo-induced deactivation (RAPID) to the reach feature sizes as small as 40 nm.
The mechanism and kinetics of photo-induced deactivation are not well understood. To better understand these processes, studies of different photoinitiators have been performed. We find that some photoinitiators are so efficient at deactivation that they are capable of undergoing self-deactivation by addition of another photon from the excitation source. This phenomenon is manifested in a polymerization trend in which feature size has a proportional velocity (PROVE) dependence, the opposite of the conventional velocity dependence. We also demonstrate that the velocity dependence can also be tuned between PROVE and conventional dependences.
Kinetic models have been formulated to account for the observed deactivation. By reconciling experimental data for some sample photoinitiators with the kinetic model through the use of simulations, kinetic rate constants are determined. The self-deactivation efficiency of each
photoinitiator was determined. The lifetimes of intermediates in the radical photopolymerization process were also determined. The kinetic rate constants associated with photoinitiators should allow for the customization of photoinitiators for specific applications and make RAPID a more efficient process capable of reaching resolution on the level of 30 nm and below.
Advisors/Committee Members: Fourkas, John T (advisor).
Subjects/Keywords: Chemistry; Nanotechnology; Polymer chemistry; deactivation; lithography; multiphoton; photochemistry; photoinitiator; resist
…Dependence
3.3.2 Photoinitiator Studies
3.3.3 Mechanism and Kinetic Modeling
3.3.4 Tuning Velocity… …Base Used as Photoinitiator for RAPID
21
1.16
Schematic Diagram of Overlapping Excitation… …Fabrication Examples Using Lucirin TPO-L as MAP Photoinitiator
56
3.3
Fabrication Examples Using… …MGCB as MAP Photoinitiator
56
3.4
Fabrication Examples Using MGC·HCl as MAP Photoinitiator… …called a photoinitiator,
PI, directly produces a radical, R• (Eq. 1.3a).
In some…
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APA (6th Edition):
Stocker, M. P. (2012). RAPID Lithography: Photopolymerization Characterization and Initiation Kinetics. (Thesis). University of Maryland. Retrieved from http://hdl.handle.net/1903/13133
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Stocker, Michael Paul. “RAPID Lithography: Photopolymerization Characterization and Initiation Kinetics.” 2012. Thesis, University of Maryland. Accessed March 05, 2021.
http://hdl.handle.net/1903/13133.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Stocker, Michael Paul. “RAPID Lithography: Photopolymerization Characterization and Initiation Kinetics.” 2012. Web. 05 Mar 2021.
Vancouver:
Stocker MP. RAPID Lithography: Photopolymerization Characterization and Initiation Kinetics. [Internet] [Thesis]. University of Maryland; 2012. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/1903/13133.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Stocker MP. RAPID Lithography: Photopolymerization Characterization and Initiation Kinetics. [Thesis]. University of Maryland; 2012. Available from: http://hdl.handle.net/1903/13133
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Bowling Green State University
11.
Polyansky, Dmitry E.
Novel Radical Peroxyester Photoinitiators: Decomposition
Mechanisms and Potential Applications.
Degree: PhD, Photochemical Sciences, 2005, Bowling Green State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1127243953
► The present thesis describes transient studies of the photodecomposition of organic peroxyesters. The successful implementation of transient techniques over wide temporal (picosecond to microsecond) and…
(more)
▼ The present thesis describes transient studies of the
photodecomposition of organic peroxyesters. The successful
implementation of transient techniques over wide temporal
(picosecond to microsecond) and spectral (UV-Vis to mid-IR) windows
allows characterization of the transient species involved in the
decomposition. The first part of the thesis illustrates a model
approach for transient studies of coumarin based peroxyesters.
Direct observation of transient species yielded the rates of decays
of singlet and triplet excited states of the coumarin chromophore
as well as provided spectra of the radical intermediates.
Particularly, to the best of our knowledge, this is the first
observation of an aroyloxyl radical by time-resolved infrared
spectroscopy. Transient studies of a series of peroxyesters
containing the 1,4-bis(phenylethynyl)benzene chromophore elucidated
the photodecomposition mechanism together with providing
information about the electronic structure of radical intermediates
involved therein. The fission of the peroxy bond leads to formation
of an aroyloxyl radical possessing 2B1 molecular orbital symmetry
with the unpaired electron delocalized through the entire
phenylene-ethynylene chormophore. This delocalization causes a
decrease in the acetylene bond order that can be observed
experimentally as a red shift of IR vibration conveying
cumulene-like character to the structure of the radical. Studies of
two-photon absorption (TPA) properties of phenylene-ethynylene
peroxyesters reveal them promising candidates for two photon
microfabrication. The compounds possess relatively high TPA
cross-sections (110 GM) and are capable of initiating the
polymerization of acrylic monomers. Model structures with 10
micrometers resolution were fabricated in two-photon process using
phenylene-ethynylene peroxyesters as photoinitiators.
Advisors/Committee Members: Neckers, Douglas (Advisor).
Subjects/Keywords: Chemistry, Physical; peroxyesters; photodecomposition; transient spectroscopy; phenylene-ethynylene; two-photon photoinitiator
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APA ·
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APA (6th Edition):
Polyansky, D. E. (2005). Novel Radical Peroxyester Photoinitiators: Decomposition
Mechanisms and Potential Applications. (Doctoral Dissertation). Bowling Green State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1127243953
Chicago Manual of Style (16th Edition):
Polyansky, Dmitry E. “Novel Radical Peroxyester Photoinitiators: Decomposition
Mechanisms and Potential Applications.” 2005. Doctoral Dissertation, Bowling Green State University. Accessed March 05, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1127243953.
MLA Handbook (7th Edition):
Polyansky, Dmitry E. “Novel Radical Peroxyester Photoinitiators: Decomposition
Mechanisms and Potential Applications.” 2005. Web. 05 Mar 2021.
Vancouver:
Polyansky DE. Novel Radical Peroxyester Photoinitiators: Decomposition
Mechanisms and Potential Applications. [Internet] [Doctoral dissertation]. Bowling Green State University; 2005. [cited 2021 Mar 05].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1127243953.
Council of Science Editors:
Polyansky DE. Novel Radical Peroxyester Photoinitiators: Decomposition
Mechanisms and Potential Applications. [Doctoral Dissertation]. Bowling Green State University; 2005. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1127243953
Australian National University
12.
Noble, Benjamin Brock.
Towards Stereocontrol in Radical Polymerization
.
Degree: 2016, Australian National University
URL: http://hdl.handle.net/1885/117000
► Despite over 50 years of research, control of the stereochemistry in free-radical polymerization using simple and scalable methods remains elusive for most common monomers. An…
(more)
▼ Despite over 50 years of research, control of the stereochemistry
in free-radical polymerization using simple and scalable methods
remains elusive for most common monomers. An attractive strategy,
which has received considerable attention, is the use of Lewis
acids to coordinate and constrain the terminal and penultimate
side-chains of the growing polymer radical. Unfortunately, the
control achieved to date usually is modest at best. In this work,
a combination of theory and experiment has been used to explore
why current methods are not optimal, with a view to designing
better control strategies. In the course of this work, the
dramatic effects of Lewis acids on other radical processes, such
as photoinitiation, were also explored, along with other aspects
of control in radical polymerization. The main findings of this
work are as follows.
Theoretical calculations revealed that a key problem with current
Lewis acid-based control agents is their binding selectivity.
Even when they bind the terminal and penultimate side-chains
selectively, this binding mode stabilizes and deactivates the
propagating radical. Moreover, it was found that a
non-stereocontrolling terminal-monomer binding mode catalyses
propagation and dominates the reaction. This propagation
catalysis, which is useful in its own right, was confirmed
experimentally using pulsed laser polymerization. On this basis,
a better control strategy, targeting simultaneous binding of the
monomer, terminal and penultimate side-chains, was proposed.
Indeed, a further theoretical examination of methacrylic acids
salts established that the reasonably high isospecificity
reported results from the formation of bridging scaffolds. The
use of methacrylic salts as ionic auxiliaries is suggested as one
potential route to isotactic polymer, and an improved method for
the conversion of calcium methylate to poly(methyl methacrylate)
was designed for this purpose.
Among the other important findings of this work was the discovery
of dramatic effects of Lewis acids on photoinitiators. While
these effects hampered pulsed laser polymerization experiments
with strong Lewis acids, strategies for avoiding them were
devised. While the effects of Lewis acids on photoinitiation were
shown to be very complex, the results presented raise the
exciting prospect of a simple route to visible light
photoinitiation. Lewis acid/ base interactions were also shown to
have dramatic effects on the redox activity of surface tethered
nitroxide radicals, work that lays a basis for ongoing research
on the use of electric fields to control nitroxide mediated
polymerization.
Subjects/Keywords: radical;
polymerization;
polymerisation;
stereocontrol;
stereochemistry;
lewis acid;
ab initio;
wave fuction theory;
density functional theory;
dft;
photoinitiation;
photoinitiator;
kinetics;
pulsed laser;
plp;
tacticity;
isotactic;
syndiotactic;
polymer;
methacrylate;
methacrylic acid;
vinyl chloride;
nitroxide;
nmp;
ion-pairing;
propagation
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APA (6th Edition):
Noble, B. B. (2016). Towards Stereocontrol in Radical Polymerization
. (Thesis). Australian National University. Retrieved from http://hdl.handle.net/1885/117000
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Noble, Benjamin Brock. “Towards Stereocontrol in Radical Polymerization
.” 2016. Thesis, Australian National University. Accessed March 05, 2021.
http://hdl.handle.net/1885/117000.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Noble, Benjamin Brock. “Towards Stereocontrol in Radical Polymerization
.” 2016. Web. 05 Mar 2021.
Vancouver:
Noble BB. Towards Stereocontrol in Radical Polymerization
. [Internet] [Thesis]. Australian National University; 2016. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/1885/117000.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Noble BB. Towards Stereocontrol in Radical Polymerization
. [Thesis]. Australian National University; 2016. Available from: http://hdl.handle.net/1885/117000
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
13.
Talungchit, Supitcha.
Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems.
Degree: PhD, Oral Science, 2012, University of Iowa
URL: https://ir.uiowa.edu/etd/2996
► Current hydrophilic resin adhesives undergo hydrolytic degradation and show a decrease in bond strength over time. Nanoleakage and ultrastructure studies suggest that inadequately infiltrated…
(more)
▼ Current hydrophilic resin adhesives undergo hydrolytic degradation and show a decrease
in bond strength over time. Nanoleakage and ultrastructure studies suggest that
inadequately infiltrated collagen leads to enzymatic degradation and
resin-dentin bond failure. Adequate degree of conversion (DC) of resin
adhesives is also critical to resin-dentin bond strength and durability. The
long-term goal of this dissertation is the realization of durable
resin-dentin bond. It is hypothesized that ethanol-wet bonding
technique (EW) may effectively facilitate the infiltration of hydrophobic monomers into
hydrophilic acid-etched dentin by maintaining interfibrillar spacing,
stiffening collagen matrix, and improving adhesive resin-demineralized dentin
matrix miscibility. Chlorhexidine (CHX), Matrix Metalloproteinase-inhibitor
(MMP-inhibitor), should further preserve collagen integrity and
resin-dentin bond strength. Moreover, efficient
photoinitiator systems that
broaden light absorptivity and provide more reactive radicals may enhance
polymerization.
In this dissertation, a clinically-relevant EW protocol, 3×15s
absolute ethanol rinsing, provided significantly higher microtensile bond strength
(πTBS) of a hydrophobic resin (70%BisGMA/30%TEGDMA) to dentin as compared to
water-wet bonding (WW). All groups showed no significant drop of πTBS
after 1-year storage except EW without CHX application, showing marginally
significant reduction in πTBS (p=0.0558) suggesting MMP-inhibition by
CHX in EW. These results were consistent with subsequent experiments. EW maintained
interfibrillar width and hybrid layer thickness for resin infiltration and retention.
Monomer molar concentration across the hybrid layer was significantly higher in EW than
WW. An application of 2% CHX diacetate further preserved collagen banding in EW. WW
showed more generalized spotted nanoleakage, while EW presented localized reticular
nanoleakage. The use of Irgacure 819 (BAPO) alone and in combination with benzoyl peroxide (BPO) or
camphorquinone (CQ) increased DC of hydrophobic and hydrophilic resins over resins
containing the CQ/amine (4E) control. Only BAPO and BAPO/BPO demonstrated significantly
higher immediate shear bond strength than CQ/4E. Within the limitations of these studies, EW improved resin-dentin bond
durability by maintaining collagen interfibrillar spaces for efficient infiltration of a
hydrophobic BisGMA/TEGDMA resin resulting in significantly higher πTBS and
monomer molar concentrations with less nanoleakage distribution within the hybrid layer
than WW. CHX further maintained collagen integrity and πTBS in EW. BAPO is a
potential…
Advisors/Committee Members: Armstrong, Steven R. (supervisor).
Subjects/Keywords: Chlorhexidine; Dentin adhesion; Ethanol-wet bonding; MMP-inhibition; Photoinitiator; Resin adhesives; Oral Biology and Oral Pathology
…bond strength. Moreover, efficient
photoinitiator systems that broaden light absorptivity and… …maintained collagen integrity and μTBS in EW. BAPO is a potential alternative
photoinitiator of… …161
CHAPTER 5 EFFECT OF PHOTOINITIATOR SYSTEMS ON DEGREE OF
CONVERSION OF HYDROPHOBIC AND… …199
CHAPTER 6 EFFECT OF PHOTOINITIATOR SYSTEMS ON RESIN-DENTIN
SHEAR BOND STRENGTH OF 3… …234
APPENDIX FORMULATION OF ETCHANTS CONTAINING
PHOTOINITIATOR…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Talungchit, S. (2012). Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems. (Doctoral Dissertation). University of Iowa. Retrieved from https://ir.uiowa.edu/etd/2996
Chicago Manual of Style (16th Edition):
Talungchit, Supitcha. “Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems.” 2012. Doctoral Dissertation, University of Iowa. Accessed March 05, 2021.
https://ir.uiowa.edu/etd/2996.
MLA Handbook (7th Edition):
Talungchit, Supitcha. “Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems.” 2012. Web. 05 Mar 2021.
Vancouver:
Talungchit S. Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems. [Internet] [Doctoral dissertation]. University of Iowa; 2012. [cited 2021 Mar 05].
Available from: https://ir.uiowa.edu/etd/2996.
Council of Science Editors:
Talungchit S. Enhancing resin-dentin bond effectiveness and durability: the role of ethanol-wet bonding technique, MMP-inhibition (chlorhexidine), and photoinitiator systems. [Doctoral Dissertation]. University of Iowa; 2012. Available from: https://ir.uiowa.edu/etd/2996
. 
Open Access Theses and Dissertations
