RAFT技术合成含醛基的嵌段共聚物

Synthesis of block polymer containing aldehyde by the reversible addition-fragmentation chain transfer polymerization

选择末端含有双硫酯结构的聚苯乙烯(分子量Mn=6 500,分散度Mw/Mn=1.05)活性链为可逆加成-断裂链转移(Reversible addition-fragmentation chain transfer,RAFT)试剂,以α,α′-偶氮二异丁腈(α,α′azodiisobutyronitrile,AIBN)为引发剂、在60℃下四氢呋喃(Tetrahydrofuran,THF)中成功实现了苯乙烯(Styrene,St)与1,2:3,4-di-O-异亚丙基-6-O-(2-甲醛-4-苯乙烯基)-D-半乳糖(1,2:3,4-di-O-isopropylidene-6-O-(2-formyl-4-vinylphenyl)-D-galactopyranose,IVDG)的"活性"/可控RAFT自由基嵌段共聚合.聚合物分子量(Mn)随单体转化率几乎线性增加,而且整个反应过程中分子量分布(Mw/Mn<1.2)保持在较窄的范围.核磁共振(1H-NMR)分析进一步证实了聚合物链的结构.

The ＇living＇/controlled radical polymerization of PS-b-PIVDG was successfully achieved using 2,2＇-azobis（isobutyronitrile） as the initiator and PS ＇living＇ chain as the macro-reversible addition-fragmentation chain transfer（RAFT） agent at 60℃ in tetrahydrofuran.The number-average molecular weight of the obtained polymers increased in direct proportion to the monomer conversion,and the molecular weight distribution was narrow（polydispersity index 1.2）.The chain structures of the obtained PS-b-PIVDG were confirmed with the 1H-NMR analysis.