多层核-壳结构P(AM-co-MAA)/W/UF复合微球制备研究

以反相悬浮聚合技术合成的丙烯酰胺(acrylamide,AM)和甲基丙烯酸(methacrylic acid,MAA)共聚高分子微凝胶P(AM-co-MAA)为模板,通过离心沉积法将微米级钨粉沉积于高分子微凝胶表面,得到具有核-壳结构的P(AM-co-MAA)/W复合微球材料;再以P(AM-co-MAA)/W复合微球为模板,通过控制甲醛和尿素的缩聚反应在模板与油/水相界面进行,制备得到了具有多层核-壳结构的高分子/钨/脲醛树脂P(AM-co-MAA)/W/Urea-formaldehyde resin]复合微球材料.利用扫描电子显微镜(SEM)、红外(FT-IR)、X射线衍射(XRD)和热分析(TGA)等手段对复合微球进行了表征.实验结果表明,外壳层脲醛树脂的包覆量、复合微球的表面形貌可通过改变甲醛和尿素溶液的浓度、甲醛和尿素的物质的量之比等因素进行控制.复合微球的导电性测试结果表明,P(AM-co-MAA)/W复合微球表面壳层脲醛树脂包覆前后,其电导率由1.9×10-3降低为0.9×10-8S·m-1.该研究获得的三层核-壳复合微球材料其外层脲醛树脂的包覆较为完整、致密,其导电性接近于绝缘材料,为含钨复合微球作为电子元件的抗辐射涂层材料打下了基础.

Preparation of P(AM-co-MAA)/W/UF Composite Microspheres with Multi-layer Core-shell Structures

Using poly(acrylamide-co-methacrylic acid) copolymer microgels prepared by a reverse suspension polymerization technique as templates,poly(acrylamide-co-methacrylic acid)/tungsten P(AM-coMAA)/W] composite microspheres with core-shell structures were fabricated by centrifugal deposition of tungsten powder on the polymer template surface.Then P(AM-co-MAA)/W/UF(urea-formaldehyde) resin composite microspheres with multi-layer core-shell structures were produced via polycondensation between formaldehyde and ure...