两水亲性嵌段共聚物对CaCO_3粒子形貌的调控

Morphological control of CaCO_3 particles by double-hydrophilic block copolymers

利用两种不同类型的两水亲性嵌段共聚物聚(N-乙烯基-α-吡咯烷酮)-b-聚甲基丙烯酸二甲基胺基乙酯(PVP-b-PDMAEMA)及聚(N-乙烯基-α-吡咯烷酮)-b-聚(2-丙烯酰胺-2甲基丙磺酸)(PVP-b-PAMPS)对无机物的矿化及调控作用,制备了特殊形貌的碳酸钙(CaCO3)粒子。扫描电子显微镜(SEM)和粉末X射线衍射(XRD)的结果表明,不同类型的两水亲性嵌段共聚物能很好地控制碳酸钙晶体的生长,且其形态和尺寸随pH变化而改变。在PVP-b-PAMPS存在下,pH=6时,呈多级片层状聚集;pH=11和9时,晶体的表面形态分别呈话梅状和蚕茧状,随着pH值的增加,PVP-b-PAMPS共聚物对CaCO3晶体的调控作用加强。而在PVP-b-PDMAEMA存在下,得到的CaCO3为层面光滑、具有多级结构的片层状聚集体。

Double-hydrophilic block copolymers,poly（N-vinylprolidone）-block-poly（2-acrylamido-2-methyl-propanesulfonicacid）（PVP-b-PAMPS） and poly（N-vinylprolidone）-block-poly（N,N-di-methylaminoethylmethacrylate）（PVP-b-PDMAEMA）,were used to prepare CaCO3 for the regulation of mineralization and morphology of inorganic particles.The as-prepared products were characterized with scanning electron microscopy（SEM） and X-ray diffraction（XRD）.The results suggested that double hydrophilic block copolymers could control CaCO3 particles with unusual,well-defined morphologies.The morphology and particle size of the CaCO3 particles changed with the variation of pH.It was revealed that with increasing pH,the effect of the polymer on the crystal control strengthen,and the particle morphology generally varies from peanut-like（pH=11）,silkworm chrysalis-like（pH=9）,to step-multilayer assemblies（pH=6） in aqueous solution of PVP-b-PAMPS.The morphology of CaCO3 particles showed step-multilayer assemblies with smooth by using PVP-b-PDMAEMA as crystal growth modifiers.