Styrene-methyl methacrylate block copolymer was obtained by the free radical telomerization: the first telomerization of styrene with carbontetrabromide by azobisisobutyronitrile (AIBN) as an initiator followed by the second telomerization of methyl methacrylate using the $CBr_3$ end group of the resulting telomer as a macrotelogen, with AIBN initiation, gave styrenemethyl methacrylate block copolymer.
Effect of the variables such as macrotelogen, initiator, temperature, solvent, and methyl methacrylate on the block copolymer yield was studied.
The microarchitecture of poly (styrene-b-methyl methacrylate) was investigated by means of bromine analysis, sequential extraction, IR, NMR, and TLC.
The highest yield of block copolymers was 20 wt% and the chain transfer constant of macrotelogen was found to be 7.8 at 70 ℃.
Styrene을 개시제인 AIBN에 의해 $CBr_4$와 telomerization 시킨후, macrotelogen으로서 생성된 telomer의 $CBr_3$ 말단기를 AIBN으로 개시반응을 일으키고 다시 MMA와 함께 telomerization시켜 Styrene-MMA block공중합체를 얻었다.
Block 공중합체의 수율에 대한 marrotelogen의 농도, 개시제의 농도, MMA의 농도, 용매, 온도, 효과를 조사하였다.
70 ℃에서 macrotelogen의 연쇄 전달 상수는 7.8이었다. 순수하게 얻은 block공중합체를 NMR,IR,TLC로서 분석 확인 하였다.
