Synthesis Of Ultraviolet-curable Silicone Materials And Photo-curing Study

The epoxy-modified silicone which could cure under the ultraviolet radiation wasobtained by the hydrosilylation reaction of poly (methylhydrogensiloxane) with unsaturatedepoxides under the catalysis of the complex of platinum and divinyltetramethyldisiloxane.The gelation occurred in the reaction which was caused by the ring-opening reaction ofoxide and the mechanism was studied while proper oxide-stabilizer was selected whichcould protect the oxides during the reaction. Result showed: (1) The preferred conditionsfor the reaction were that the mass fraction of catalyst was 0.087％of the monomer; themolar ratio between unsaturated epoxides mad poly(methylhydrogensiloxane)was 1: 1.2;the reaction time was 8 hours the reaction temperature was 80℃. Under the aboveconditions, the conversion rate of poly (methylhydrogensiloxane) could reach 95.6％. (2)The complex of platinum and divinyltetramethyldisiloxane was more effective than thecomplex of platinum and isopropanol. (3) Ethanol which was used as epoxide-stabilizercould prevent the ring-opening reaction of epoxides.The relationship between cure time and mass fraction of different photoinitiators orphotosensitizors and the effect of MQ resin's mass fraction on the release force andthermo-property was studied. Proper solvent was selected and used with the oligomer todeduce the thickness of coating. The result showed: (1) Triarylsulfonium salts was moreeffective than diaryliodonium salts. (2) Phenothiazine which was used as photosensitizercould make the photoinitiator more effective. (3) The mixture of benzine and xylene(xylene: benzine=1:1.5) was used as solvent in which the oligomer photo initiator andphotosensitizers had a good solubility. (4) MQ resin could promote the release force andthermeoresistance.