| Polysiloxane resin can be cured by condensation of Si-OH or hydrosilylation, and their cured product has excellent resistance, high and low temperature performace and adjustable flexibility. They are widely used in the area of bonding and sealing, which become essential materials in the aerospace, electronics and other fields. Research and development of the new curing method is an important direction in the area of silicone materials. The functionalized polysiloxane resin (Acrylate and alkoxy-terminated polysiloxane, ATPS) was designed and synthesized, which combined fast curing of UV curing technology and convenient moisture curing. The problems of the existence of the shadow in the UV curing and slow positioning in the moisture curing were solved by the synthesis of ATPS, which extending the application of silicone materials. Therefore, the study of the new functionalized polysiloxane resin (ATPS) has not only very important practical applications, but also has instructive development of UV curable prepolymer.In this thesis, the reaction conditions and raw materials ratio on the synthesis were investigated, the structure of the resin was characterized by IR,1H-NMR,13C-NMR and 29Si-NMR. The dual cure mechanisms were studied by real-time infrared (RTIR) and plane-knife method, and also thermal properties were considerred by DSC and TG.1. ATPS with acrylate and alkoxy-terminated groups was synthesized by transesterification reaction ofγ-(methacryloyloxy)propyltrimeth oxysilane with hydroxyl-terminated polydimethylsiloxane, and the reaction route system was also established.2. ATPS was characterized by IR and NMR, its characteristics of dual curing and long linear structure were proved and determined.3. Dual curing behavior of ATPS was studied, the addition of photoinitiator, light intensity and different photoinitiator types were influenced by the compatibility of dual-curing prepolymer in the UV curing process. In Moisture curing process, the gel time was measured, according to the formula of Arrhenius, the moisture curing apparent activation energy was 23.2kJ/mol, frequency index lnA=-5.466, which was tested at 28% relative humidity.4. Adding the amine accelerator and activity diluent to increased ATPS' UV curing rate were investigated. The results showed that the amine accelerator in this system was its own inhibitor stronger than the inhibition of oxygen inhibition, leaving the curing rate decrease; By adding the Si-contained diluents, the curing rate can be accelerated at a certain extent.5. Thermal properties of dual curing product were studied by DSC and TG. The results show that the Tg was -81.4℃, the temperature of thermal decomposition of cured product 10% was 427.8℃. After the formula projections, the thermal decomposition activation energy was 129.3kJ/mol, which can be drawn from the projected formula.6. polysiloxane modified Photoinitiator was synthesized from polymethylhydrosiloxane(PMHS) by dehydrocoupling reaction. The experiments showed that the Si-contained photoinitiator had good compatibility with ATPS. |
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