| Summary: | 碩士 === 國立臺北科技大學 === 有機高分子研究所 === 100 === The differences of static and kinetic behaviors under constant temperature while use three functional radicals resin and epoxy cationic type UV curable resins. Three different in situ monitoring techniques including photocalorimetry(DPA)、rheometer
(Physica) and real time FT-IR(RT-IR) were used in order to investigate the kinetics of the photopolymerization process.
The free radical type photopolymerization mixtures of trimethylolpropane triacrylate (TMPTA) which has three acrylic groups was added with cleavage photoinitiator HMPP, and the cationic type photopolymerization mixtures of 3,4-Epoxycyclohexylmethyl-3,4-cyclohexanecarboxylate(CELLOXIDE 2021P) that was added with Lewis acid photoinitiator UVI 6976. After that, we prepare different concentrations respectively then formed cross-linking network structures by irradiated ultraviolet beam.
During the curing process, Photo-DSC which is also called DPA (Double Beam Photocalorimetric Accessory) was used to detect the endothermic or exothermic reaction heats, then converting to calorimetric conversions and were used for Kamal’s model；Real-time FTIR was used to investigate the evolution about the ratio of characteristics peak to standard peak by adding ultraviolet beam, then converting to conversions and were also used for Kamal’s model to test and verify the UV-curing’s data under static behavior with DPA. On the other hand, rheometer was used to get rheological conversions that were calculated from storage modulus (G’) during curing processes, the values are used for Malkin and Kulichikhin’s model to indicate the data about kinetic behavior UV-curing.
Free radical and cationic UV curable systems in the static measurement(DPA、RTIR) were both observed to have critical values for the amounts of photoinitiator in isothermal environment；In the kinetic measurement (Physica), we found that Free radical type also have an extreme values and existed ”Trommsdorff effect”. However, the G’∞ of cationic photopolymerization was affected due to chain growth mechanism interfered with dynamic shear strain on intermediate of decomposed photoinitiator.
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