The macromolecular brushes

PI-g-P(TFEMA-co-HEMA-tms) was synthesized via atom transfer radical polymerization(ATRP)

using polyimide with bromide side-group (PI-Br) as the macroinitiator and 2

2-bipyridine/CuCl as catalytic system

trifluoroethyl methacrylate (TFEMA) and 2-(trimethylsilyloxy)ethyl methacrylate (HEMA-tms) as the comonomers.PI-g-P(TFEMA-co-HEMA) with hydroxyl group in its side chains was generated by removing of trimethylsilyl groups under mild acidic condition.Finally

PI-g-P(TFEMA-co-HEMA-P) with phosphite groups (P) in its side chains was further synthesized by reaction between hydroxyl group of side chains

PHEMA and diethyl chlorophosphate.The structure of the resultant brushes was verified by1H-NMR

FTIR et al.Differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA) were used to evaluate the thermal properties of the resultant macromolecular brush.The results show that PTFEMA chain segments decompose at around 120℃

and the PHEMA chains decompose at about 250℃

while the decomposition of PI backbone is over 425℃.The structure composition of the brush PI-g-P(TFEMA-co-HEMA) analyzed from TGA has a good agreement with the result calculated from 1H-NMR.The solubility tests indicate that the composition of the side chain has significant influence on the solubility of the brush.