Study On Polymerization And Mechanism Of N-Substituents Propioamide Catalyzed By R₃P/R₃N

The new approach of polymerization was still being the target of people working on synthesis of polymer especially in the synthesis of functional polymer. In recent years, catalytic systems of organic base have become hotspots in research, and in the monomer aspects the focus of research from alkenes monomers gradually towards alkynyl monomers. Our research group has been working on polymerization of propynamide and its derivatives catalyzed by lewis base. This paper is aimed at the mechanism of polymerization and the content including mechanism, the structure and property of polymer, the reaction kinetics.This thesis research contents consists of three parts:1. Polymerization of propiolamide catalyzed by several different lewis base, such as R3P/R3N; 2. The derivatives with different substituent are synthesized, such as N-methylpropynamide and N-(4-butylphenyl)-propynamide. They are polymerized using lewis base as catalyst, then compare their polymers with poly (N-benylpropynamide) under same conditions; 3. We put foeward the method of 1H-NMR trace to reseach on the methanism of polymerization.The polymerization of propynamide can happen catalysted by tertiary phosphonite and tertiary amine, but the result of MALDI-TOF showed the molecular weight of polymer is 500-900 catalysted by tertiary phosphonite, and the molecular weight of polymer is 200-1200 catalysted by tertiary amine. The addition polymerization of N-methylpropynamide and N-(4-butylphenyl)-propynamide catalyzed by lewis base was discussed, and the results of FT-IR, 1H-NMR 13C-NMR and MALDI-TOF showed the structure of polymers. From the MALDI-TOF, we can see the degree of poly (N-(4-butylphenyl)-propynamide) is 5-19 and poly (N-methylpropynamide) is 3-9. Different reaction conditions such as monomer concentrations, temperatures and solvents were also discussed. In 1H-NMR trace test, the disappear of secondary amine hydrogen and alkynyl hydrogen verified the process of proton transfer, and the peak of -NH at 8.66ppm reappeared after deactivation, thus verified zwitterion. The results also indicate that the reaction mechanism of lewis base catalyzed electron-withdrawing acetylenes:proton transfer/nuclephilic addition polymerization.