Preparation Of New Type Initiator And Related Research For Polymerization

Radical polymerization is often used for large-scale production of various vinyl polymers and their materials. In general, initiators are used for igniting the polymerization. So the research on initiators keeps attractive. Until now, AIBN and BPO are two of commonly used initiator. However, they are unstable, explosive and inconvenient for transportation and storage.Carbon-carbon bond initiator has some virtues, such as stability for reaction and convenient storage. Since the last century 70’s it has drawn researchers’attention. The so-called carbon-carbon bond initiators are such a class of organic compounds:they all contain the weak carbon-carbon single bond owing to being with electron-withdrawing or conjugate groups so as to be lengthened. So they are easy to be broken into free radicals. Yet, due to the bond carrying multi-group of electron-withdrawing, the generated radicals are very steady and less active for initiation. And so far, the carbon-carbon bond initiators of symmetrical structure were investigated. Only one kind of radical was produced through hemolytic reaction.In this paper, a kind of carbon-carbon bond compounds with asymmetric structure was synthesized with different groups attached to the ends of carbon-carbon bond. These compounds have a higher efficiency in initiating polymerization of acrylate and styrene. Meanwhile they are still stabile for storage and transportation, and have the stable process of initiating polymerization. Moreover, the preparation method for them is very simple with common materials.The first chapter is the introduction to free radical polymerization methods, and free radical polymerization initiators. Our direction of the research is also provided. In the second chapter, four compounds, namely,2,3-two phenyl butyronitrile,2-(4-methoxyphenyl)-3-phenyl butyronitrile,2-(4-chlorophenyl)-3-phenyl butyronitrile and 2,2,3-three phenyl butyronitrile, were synthesized and characterized by NMR and IR. In the third chapter these compounds were used for polymerization of styrene and MMA, the results show that the first three compounds have an excellent initiating activity and the last 2,2,3-three phenyl butyronitrile is inhibitive. The fourth chapter discussed the initiating mechanism, and the experimental results also confirm the compounds’structure have remarkable effects on activity. The last chapter summarizes the research.