| Summary: | 碩士 === 國立高雄應用科技大學 === 化學工程與材料工程系博碩士班 === 106 === Type II photoinitiator systems are widely used in photocuring processes due to their low cost, faster photospeed which applied in many industrial applications such as photoresist dry film and imaging. One of the typical Type II photo-initiator package based on o-Cl-HABI (hydrogen acceptor) and NPG (hydrogen donor) systems (where o-Cl-HABI is a 2-chlorohexaaryl biimidazole, NPG is an N-phenyl glycine) was investigated in this study. The photocuring behavior for different weight ratios of o-Cl-HABI and NPG was studied through FT-IR, gel-fraction, electron spin resonance (ESR) and photoluminescence (PL) methodologies. As the amount of NPG increased from 0.05 wt% to 0.1and 0.25 wt%, the faster curing speed was achieved. However, the curvature photo-reactivity phenomenon was observed as the amount of o-Cl-HABI at 0.5, 1 and 2 wt%, respectively. In this study, the air and nitrogen atmospheres effect are conducted.
Since NPG is an important factor on the photocuring reactivity, the structural modification of NPG is also performed for comparison. The p-OCH3, -Cl, -NO2 NPG derivatives were synthesized accordingly. These structures were identified by 1H-NMR and mass spectrometry. The NPG derivatives exhibited melting temperatures of 146-238 oC that was higher than the reference NPG (127 oC). The NPGs also displayed good solubility in Acetone, THF and DMF. In addition, the molar extinction coefficients of NPG, OCH3-NPG, Cl-NPG and NO2-NPG were 4.34×104 M-1cm-1, 2.36×104 M-1cm-1, 2.08×104 M-1cm-1, 1.13×103 M-1cm-1, respectively.
In addition, the HOMO, LUMO levels and their corresponding ΔGET values were calculated to correlate with the photoreactivity. The double bond conversion was final tested through the gel fraction method under the same weight ratios (o-Cl-HABI/NPG = 2:0.05 wt%). The order of conversion rate is NPG > OCH3 -NPG > Cl-NPG > NO2-NPG that is consisted with ΔGET values mentioned above.
|
|---|
