摘要
以α-溴乙苯为引发剂, 溴化亚铜为催化剂, 2,2′-联吡啶为配体, 用原子转移自由基聚合(ATRP)法合成了结构一定的嵌段共聚物聚苯乙烯-b-聚丙烯酸丁酯(PSt-b-PBA). 经水解制备了双亲性嵌段共聚物聚苯乙烯-b-聚丙烯酸(PSt-b-PAA);采用单溶剂溶解法配制了PSt-b-PAA在甲苯中的反胶束溶液;以极性荧光化合物N-1-萘乙二胺盐酸盐(NEAH)为极性微区探针, 用荧光光谱法并配合透射电镜观察探索了双亲嵌段共聚物PSt-b-PAA在甲苯溶液中的自聚集行为, 考察了双亲性嵌段共聚物浓度、链结构及温度等因素对反胶束化行为的影响规律. 结果表明, 亲水链PAA短而亲油链PSt长的双亲嵌段共聚物PSt-b-PAA, 用单溶剂溶解法可使其在甲苯中发生自聚集, 形成以亲水段为核, 疏水段为壳的星状反胶束结构;反胶束为10～20 nm的球形聚集态结构;PSt-b-PAA的自聚集行为及临界胶束浓度与分子链的微结构和温度等因素相关, 且随着共聚物浓度的增大, 小胶束会逐渐结合形成大的纺垂状聚集体.
The block copolymer of PSt-b-PBA with well-defined structure was synthesized via atom transfer radical polymerization（ATRP） by using 1-phenylethyl bromide（1-PEBr） as the initiator, cuprous bromide as the catalyst, 2,2＇-bipyridine（bpy） as the ligand and xylene as the solvent. The block copolymer PSt-b-PBA was characterized and the living polymerization was validated by GPC, FTIR, and ~H NMR. Then the amphiphilic block copolymer of PSt-b-PAA was prepared by alkaline hydrolysis of PSt-b-PBA. The reversed mi- cellization behavior of PSt-b-PAA in toluene was investigated by fluorescence probe technique with polar fluorescence compound N-（1-naphthyl） ethylenediamine dihydrochloride （ NEAH ） as a polar fluorescence probe and by the observation of TEM. It was found that NEAH as a polar fluorescence compound can clearly reveal the reversed micellization behavior of PSt-b-PAA in toluene. The results show that the reversed micelles which have hydrophilic core and hydrophobic shell can formed spontaneously through self-aggregation of PSt-b-PAA macromolecules in toluene, the aggregates have the morphology of sphere, and the self-aggregation behavior of PSt-b-PAA depends apparently on the microstructure of the macromolecules and the temperature. The longer the PAA block is, the lower the critical micelle concentration is; the higher the temperature is, the lower the critical micelle concentration is.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2005年第12期2381-2385,共5页
Chemical Journal of Chinese Universities
基金
山西省自然基金项目(批准号:20040402)资助
关键词
自聚集
反胶束
极性荧光探针
苯乙烯-丙烯酸双亲嵌段共聚物
Self-aggregation
Reversed micelle
Polar fluorescence probe
Amphiphilic block copolymer ofstyrene-acrylic acid
