Preparation And Characterization Of Functionalized Modified Polyphenylene Ether

Poly(phenylene ether)PPE)is one kind of high-performance resin,also as one of the five common engineering plastics in the world,is widely used in communications and electronics industry because of its excellent dielectric properties.With the rapid development of 5G(The Fifth Generation)telecommunication technology in recent years,new dielectric materials are in high demand.As an important resin used in high-frequency/speed copper clad laminate(CCL),the PPE needs further improvement on processability and thermal stability.In this thesis work,we aimed at chemical modification of the PPE in order to improve its comprehensive performance.Functionalized PPE(MPPE)was synthesized successfully by end-capping PPE(Noryl-SA90)using 2-methylacrylic acid anhydride and 4-maleimide benzyol chloride.The chemical structure and properties of MPPE were characterized by infrared spectroscopy(FTIR),proton nuclear magnetic resonance spectroscopy(1H NMR),differential scanning calorimetry(DSC)and thermogravimetric analysis(TGA).The results imply that the hydroxyl end-groups were completely acylated.There are two curing peaks in the first heating curve of DSC,so MPPE can undergo cross-linking reaction.The glass transition temperature Tg of MPPE(1)increased to 150?,Td5%to 341? and Td50%to 460?,in comparison with PPE Noryl-SA90(Tg=132?,Td5%=357?,Td50%=457?).The Tg of MPPE(2)was 212?,Td5%427? and Td50%470?.The cure kinetics of MPPE(2)was then studied by DSC in different heating rates.The results showed that the gel temperature,curing temperature and post-treatment temperature of the first and second curing peak were 162.9?,183.7?,214.8? and 214.8?,275.3?,326.1?.The modified copolymers PPE(P1-P4)were successfully prepared by copolymerization of using 2,6-dimethylphenol and 2,6-diphenyl phenol.The chemical structures and properties were characterized by Fourier transform infrared spectroscopy(FTIR),proton nuclear magnetic resonance spectroscopy(1H NMR),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA)and gel permeation chromatography(GPC).The results showed that the higher the proportion of DPP units are in the main chain and the larger the molecular weight and the higher the glass transition temperature of copolymers PPE.The homopolymer PDPP was synthesized in the same way.The chemical structures and properties were studied,and the results indicated that the number-average molecular weight of PDPP was 13500 and the molecular weight distribution was 1.50.The Tg of PDPP was 173?,Td5%497?and Td50%581?.