| Oxetane monomers have attracted the interest of many researchersin the field of cationic photopolymerization.Such monomers have small viscosity,low toxicity and low volatility,and have a good dilution effect.Besides,they are not affected by oxygen,shrinkage rate of the cured materials is low and the adhensive property is excellent.Unfortunately,it form a stable structureintermediates in the process of photopolymerization,leading to a pronounced induction period,and the macroscopically manifested that the coating is often difficult to cure.In recent years,the hybrid photopolymerization system has developed rapidly.The hybrid photopolymerization system combines the advantages of free radical photopolymerization and cationic photopolymerization.The synergy between the initiators of the two systems and the complementarity between the performances can be ideal result.In this paper,Photo-DSC was used to study the photopolymerization kinetics of oxetane monomers.Mainly analyzes the influence of free radical initiator to oxetane monomers photopolymerization kinetics,as well as syudied the oxetane monomers photopolymerization kinetics by adding more active monomers than oxetane monomers.The results showed that suitable free radical initiator has the promoting effect to oxetane monomers,adjusting appropriate proportion for active monomers and oxetane monomers can significantly reduce induction period of oxetane monomers,promote the process of photopolymerization.Based on the study of oxetane monomers,this paper synthesized the hybrid monomers containing oxetane and methacrylate double bonds in the same molecule,compared with the hybrid system,the resistance to oxygen of hybrid monomersignificantly increased.Besides,we also further study the hybrid photopolymerization kinetics behavior of hybrid monomers.The effects of different types of initiators on the photopolymerization kinetics of hybrid monomers were investigated.From the results,we can conclude that under the same conditions,adding the same amount of free radical initiator has more obvious promote effect to the system. |
