PS-b-PNIPAM/Ag复合微粒的制备与表征

Preparation and Characterization of PS-b-PNIPAM/Ag Composite Particles

采用原子转移自由基聚合(ATRP)法合成了聚苯乙烯-b-聚(N-异丙基丙烯酰胺)(PS-b-PNIPAM)两亲性嵌段共聚物,并以其为模板,聚乙烯亚胺(PEI)作为银离子和嵌段共聚物PS-b-PNIPAM的交联剂以及还原剂,制备了PS-b-PNIPAM/Ag复合纳米微粒.利用透射电子显微镜(TEM)、X射线衍射(XRD)和傅里叶变换红外(FTIR)光谱对复合纳米微粒的形貌及其成分进行了表征.X射线衍射和电子衍射证明银纳米微粒具有良好的面心立方体单晶结构.研究结果表明,不同浓度的两亲性嵌段共聚物PS-b-PNIPAM在丙酮中形成的胶束模板对银纳米粒子的尺寸及其分布有重要的影响.

Amphiphilic diblock polystyrene-b-poly（N-isopropylacrylamide）（PS-b-PNIPAM） was used as a template for metal-block copolymer nanocomposite formation.Diblock copolymers were synthesized using the atom transfer radical polymerization（ATRP） method.Polyethyleneimine（PEI） acted as a crosslinking agent between Ag ions（Ag nanoparticles） and PS-b-PNIPAM colloids and was the reducing agent during the formation of Ag nanoparticles.The product was characterized by Fourier transform infrared（FTIR） spectroscopy,X-ray diffraction（XRD）,and transmission electron microscopy（TEM）.Silver crystals were monocrystalline with face-centered cubic structures,which was confirmed by electron diffraction and XRD.Results revealed that the size and size distribution of the resulting silver nanoparticles based copolymer were strongly dependent on the ratio of the initial copolymer solution to silver concentration.