ATRP法制备纳米铜/PMMA-b-PSt复合材料及其表征

Synthesis and Characterization of Nano-Copper/PMMA-b-PSt Composites by Atom Transfer Radical Polymerization

在超声辐射作用下,以α-溴代丙酸乙酯为引发剂,溴化亚铜/2,2-联吡啶为催化体系,通过原子转移自由基聚合(ATRP)制备了预聚物PMMA-Br。以此预聚物为大分子引发剂,苯乙烯为共聚单体进行ATRP反应,制得PMMA-b-PSt嵌段共聚物。通过硼氢化钠还原聚合物体系中的溴化亚铜,制得纳米铜/PMMA-b-PSt复合材料。采用红外吸收光谱(IR)、核磁共振(1H-NMR)、凝胶渗透色谱(GPC)和透射电子显微镜(TEM)等手段对样品进行表征,并用热重分析法对样品的热性能进行了研究。实验结果表明,采用超声方法成功合成了以PMMA-b-PSt为壳和纳米铜为核的复合材料,并发现这种复合材料可以形成以PMMA-b-PSt为连续相和纳米铜为分散相的圆环状组装结构,热分析结果表明纳米铜粒子的存在降低了嵌段共聚物的分解温度。

Prepolymer of poly（methyl methacrylate） with single-caped halogen（PMMA-Br） was synthesized with ethyl α-bromopropionate as initiator and CuBr/2,2-bipyridine（BPy） as catalytic system by using atom transfer radical polymerization（ATRP） method under ultrasonic irradiation. Then block copolymer poly（methyl methacrylate）-b-polystyrene（PMMA-b-PSt） was synthesized with PMMA-Br as macromolecular initiator and styrene as monomer of copolymerization by ATRP reaction. Nano-copper/PMMA- b-PSt composites were prepared with NaBH4 as reductant of CuBr in the polymerization system. The polymerization sample was characterizated by means of FT-IR, 1H-NMR, GPC and TEM. Its thermal property was analyzed by TG. Testing results show that the composite with PMMA-b-PSt as shell and nano-copper as core was successfully synthesized by ultrasonic method, and it can form a circle assembly structure with PMMA-b-PSt as the continuous phase and nano-copper as dispersed phase. TG result shows that the decomposition temperature decreases beause ofnano-copper particle existing in the block copolymer.