Cationic polymerization of pMethoxystyrene (pMOS) was achieved in imidazole phosphate ionic liquid 1butyl3methylimidazolium hexafluorophosphate (［bmim］［PF6］) with 2chloro2,4,4trimethyl pentane (TMPCl) and boron trifluoride (BF3) as a initiating system at -10 ℃. The polymer molecular weight achieved 73 150 g/mol, and monomer conversion was more than 93.4%. The influence of reaction temperature and monomer concentrationon the polymerization was analyzed, and the molecular structure was characterized by 1HNMR.The results showed that there were two different ends structure of polymer, including chlorine end groups and double bond end groups, and the corresponding mechanism of cationic polymerization of pMethoxystyrene in ionic liquid was proposed.

Butyl rubber solution directly can be obtained in the synthesis of butyl rubber by solution process,which shortens the bromination steps. While in this process it is difficult to remove the isobutylene monomer in butyl rubber solution completely because of the great airtightness of butyl rubber.The mass concentration of residual isobutylene in butyl rubber solution was effectively determined by Headspace Gas Chromatography. The effects of residual isobutene monomer on bromination of butyl rubber were investigated. The results showed that the bromine content decreased rapidly, while the mole ratio of structure II and structure III increased with the increasing of the concentration of isobutylene.