星状多臂共聚物h-PCMS-g-PEMA-b-PMMA的合成

Synthesis of Star-shaped Multi-arm Polymer h-PCMS-g-PEMA-b-PMMA

在Cu Cl/bpy催化体系下,通过对氯甲基苯乙烯(CMS)自引发制得球状超支化聚对氯甲基苯乙烯(h-PCMS),再以h-PCMS作为大分子引发剂,通过两步原子转移自由基聚合(ATRP)成功在球状h-PCMS表面接枝二嵌段聚合物聚甲基丙烯酸乙酯-b-聚甲基丙烯酸甲酯(PEMA-b-PMMA),合成了星状多臂共聚物h-PCMS2700-g-PEMA41000-b-PMMA15000(下标为分子量),分子量分布为1. 6,其结构和性能经1H NMR、IR、GPC和DSC表征。通过1H NMR定量分析表明,h-PCMS中的苄基氯具有活性,可进一步引发接枝反应,次苄基氯不能引发ATRP反应。在每一个h-PCMS表面有接近三分之一的苄基氯参与接枝反应,接枝臂数为6。

Spherical hyperbranched poly（chloromethyl styrene）（ h -PCMS） was prepared by self-initiated polymerization of chloromethyl styrene（CMS） catalyzed by CuCl/bpy. A two-block polymer, polymethyl methacrylate- b -polymethyl methacrylate（PEMA- b -PMMA）, was grafted on the surface of h -PCMS by two steps of atom transfer radical polymerization（ATRP） initiated by h -PCMS, to afford the star-shaped multi-arm copolymers h -PCMS 2700 - g -PEMA 41000 - b -PMMA 15000 （subscripts refering to molecular weight）, the molecular weight distribution is about 1.6. The structure and properties were characterized by 1 H NMR, IR, GPC and DSC. It was confirmed by 1 H NMR that benzyl chloride in h -PCMS was active, which could lead to further graft reaction, and secondary benzyl chloride could not initiate ATRP reaction. Approximately one-third of the benzyl chloride was involved in the grafting reaction on each h -PCMS surface resulting in a graft arm number of 6.