摘要
以三硫代碳酸(α,α′-二甲基α-″-乙酸)酯为链转移剂,苯乙烯为第一单体,通过RAFT聚合技术合成出大分子链转移剂(PS-CTA);以甲基丙烯酸-N,N-二甲氨基乙酯为第二共聚单体合成出具有不同链长的三嵌段聚合物。GPC对PS-CTA的表征表明:PS-CTA的分子量分别为2100、3500和5000g/m o l,分子量分布约为1.03;NM R表征确定了三嵌段共聚物的结构。三嵌段共聚物在选择性溶剂中可自组装成胶束,通过TEM观察发现胶束呈球形;并且胶束的尺寸随嵌段共聚物分子量的增加而增加。
Polystyrene homopolymers synthesized via Reversible Addition-Fragmentation Chain Transfer polymerization were used as macro-chain-transfer agents to synthesize amphiphilic triblock copolymers with two hydrophobic blocks of PS and one hydrophilic block of PDMAEMA. All Macro-CTA were characterized by GPC and NMR, the molecular weight of the Macro- CTA were 2100 g/mol, 3500 g/mol, 5000 g/mol, respectively, and all the Polydistribution Index were about 1.03. The structure of triblocks copolymers were confirmed by NMR. The shape of the micelles were studied by TEM. It is found that the shape of the micelles assembled in aqueous solution is sphere, and a layer PDMAEMA is confirmed by EDS in the surface of dried micelles, the size of the micelles is increased with the length of macromolecular, especially with length of the hydrophobic blocks. The thermo-and pH-sensitivity of the micelles were also investigated.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2006年第3期88-92,共5页
Polymer Materials Science & Engineering
基金
国家自然科学基金资助项目(20374040)
