The Studies On The Hybrid Cationic Photopolymerization

Photopolymerization of multifunctional monomers or oligomers, also called photocuring, has become a well-accepted technology which has been found a large variety of industrial applications because of its unique advantages, such as efficient, enabling, economical, energy-saving, environmental friendly, etc.In this thesis, two photoinitiator (Uâ…¥-6976 and Omnicat-440) were chosen, and the photopolymerization of two blend photopolymerization systems(K126/DVE-3, E114/DVE-3) were investigated by real-time infrared spectroscopy (RT-FTIR). The kinetics results indicated that the reactivity of Uâ…¥-6976 was higher than Omnicat-440. When the concentration of photoinitiator was 4.0%, and the light intensity was 100mW/cm~2, the change of the ratio of K126/DVE-3 and E114/DVE-3 which was 3: 1, 1 : 1, 1 : 3, the conversion of epoxy group increased with the increasing of DVE-3 in each system, however, the conversion of double bond decreased with the increasing of DVE-3. The vinyl ether would promote the polymerization of epoxy group. Three novel hybrid monomers 2-(1-propenyl)oxyethyl glycidyl ether (POEGE) , 4-(1-propenyl)oxybutyl glycidyl ether(POBGE) and 6-(1-propenyl)oxyhexyl glycidyl ether (POHGE), were synthesized via three steps reaction. The products were characterized by Fourier Transform Infrared (FTIR) and ~1H-NMR spectroscopy. The photopolymerization characteristics of these monomers were investigated by Fourier Transform Real Time Infrared spectroscopy (FT-RTIR). The results indicated that the final conversion of epoxy group and double bond were increased with increasing the initiator concentration and light intensity. The results showed that different chain length had significant effect on the conversion of double bond and the epoxy group, the conversion of 1-propenyl ether double bonds decreased with the increasing of the chain length and the conversion of epoxy groups increased with the increasing of the chain length. The photopolymerization of K126/POEGE and E114/POEGE were investigated. The results indicated that the conversion of aliphatic epoxy group and the conversion of alicyclic epoxy group increased with the increasing of K126 and E114. The conversion of double bond in POEGE increased with the increasing of K126 and E114.