Synthesis And Application Of Block Copolymer Within Polymerized Ionic Liquid

In this article, block copolymer within poly ionic liquid was synthesized by reversible addition-fragmentation chain transfer (RAFT). Influence of different monomer density on block copolymer and properties of different chain proportion of the block copolymer was investigated. The molecule weight and its dispersity index was investigated by means of gel permeation chromatography(GPC). And molecule structure of product was characterized through FT-IR and 1H-NMR. After the best monomer density confirmed, different chain proportion of the block copolymers and graphene were added intopropylene carbonate, DMF and toluene to explore stability of graphene with the effect of block copolymer. Otherwise, block copolymer was added into graphene/PS nanocomposite to investigate the dispersion of graphene in the nanocomposite through TEM, and thermal stability of composite was characterized by means of DSC and DMA. The results showed that:(1) Molecule weight and its dispersity index can be controlled effectively by RAFT living radical polymerization;(2) Agglomeration of graphene in organic solvent can be improved by adding PS-b-PVBnMeImPF6, and the more block copolymer, the better of the dispersion.(3) After PS-b-PVBnMeImPF6 added into PS, different chain proportion of block copolymers all had plasticization. And the lower molecule weight, the stronger plasticization. It had little influence on Tg of PS when only graphene added into it.(4) When PS-b-PVBnMeImPF6 was added into Graphene/PS nanocomposite, the interaction of block copolymer and graphene made good dispersion of graphene. Not only covered the decrease of Tg of composite, but increased Tg when compared with PS. And graphene can improve storage modulus of PS basis.(5) It was found that chain proportion of 1:0.4 and 1:0.5 had more influence on Tg when PS-b-PVBnMeImPF6 was added into Graphene/PS nanocomposite.(6) It was found that Tg of Graphene/PS nanocomposite increased slightly with amount of PS-b-PVB0.1MeImPF6 increased when the same chain proportion of block copolymer was added into Graphene/PS nanocomposite. It showed that increase rate of π-π conjugation between block copolymer and graphene was faster, and increase rate of plasticization was slower.(7) RGO was synthesized successfully and characterized by means of FT-IR and Raman spectra. The RGO/PS-b-PVBMeImPF6 composite was synthesized by solution-mixing method. Result showed that the stability of RGO/PS-b-PVBnMeImPF6 was better than pure RGO in PC and in toluene, and the stability of RGO/PS-b-PVB0.5MeImPF6 was the best.