摘要
将活性负离子聚合与原子转移自由基聚合(ATRP)技术相结合,运用机理转移法制备了一种两亲性材料聚丁二烯-b-聚(甲基丙烯酸N,N-二甲氨基乙酯)(PB-b-PDMAEMA)嵌段共聚物.首先通过负离子聚合方法设计合成聚丁二烯,用环氧丙烷封端,2-溴异丁酰溴作酯化剂,合成具有活性端基溴的聚丁二烯大分子引发剂(PB-B r),再用其引发亲水性单体DMAEMA进行原子转移自由基聚合,聚合动力学证实了该聚合反应具有典型的活性/可控自由基聚合的特征.通过差示扫描量热法(DSC)研究嵌段共聚物的微相分离行为.制备的大分子引发剂及两亲性嵌段共聚物经凝胶色谱、红外和核磁表征证实了预定的结构.
A amphiphilic block copolymer of polybutadiene（（PB）-b-poly[2-（dimethylamino））ethyl methacrylate]（PDMAEMA） was synthesized by transformation of living anionic polymerization into atom transfer radical polymerization（ATRP）.The macroinitiator,PB containing the 2-bromoisobutyryl end group（PB-Br） was attempted by anionic polymerization of butadiene with butyllithium initiator,then the living PB was chain extended with propylene oxide（PO） and terminated by 2-bromoisobutyryl bromide（BriBBr）.By using PB-Br with controlled molecular weight（M（n） = 5.7×10^3）,high bromine content（the bromating efficiency,92.1%） and low polydispersity（M（w）/M（n） = 1.07） as macroinitiator and CuBr/N,N,N′,N″,N″-pentamethyldiethylenetriamine（PMDETA） as catalyst and ligand,ATRP of hydrophilic DMAEMA was realized at 50℃.Kinetics studies reveal a controlled/living polymerization for DMAEMA.The GPC curve of the diblock copolymer indicates a successful initiation and growth of the second block,showing a symmertrical peak due to the removal of uninitiated marcoinitiator.Microphase separation behavior of the diblock copolymer was studied by DSC technique.The properties of the PB-Br and amphiphilic block copolymer PB-b-PDMAEMA were characterized by^1H-NMR,FTIR in detail.Polydispersity of the diblock copolymer remained low（M（w）/M（n）= 1.27） for ATRP of DMAEMA.Estimated by^1H-NMR,the resulting copolymer was expressed as PB（（10））-b-PDMAEMA（（23））.The results show that well-defined target products with controlled molecular weight and low dispersity were obtained.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2010年第2期143-148,共6页
Acta Polymerica Sinica
基金
国家自然科学基金(基金号20674007)资助项目
