PRODUCTION OF HIGH FUNCTIONAL COMPOSITES AND MOLECULAR DESIGN・CONTROL OF INTERFACIAL STRUCTURE BY PROBING THE ADSORPTION LAYER OF POLYMERS

复合材料的分散性、填充粒子的取向度对复合材料的高性能至关重要。这些性质取决于吸附的聚合物层对颗粒的排斥力(通过聚合物链的渗透压和熵弹性)，因此本研究对这些吸附的链的构象进行了研究。通过贵金属聚合技术合成了端基单分散聚合物(活性阴离子聚合)、氨基聚合物(自由基聚合)。通过表面力仪器(1995年)、原子力显微镜(1996年)、动态光散射仪、椭偏仪、表面张力仪、电子显微镜、表面力-表面压力仪、流变仪等技术研究了聚合物在二氧化硅、氧化铁表面的吸附构象。高分子链在二氧化硅、氧化铁表面的吸附构象可以用所谓的环点模型来表示，其中极性官能团与金属氧化物表面(表面覆盖着羟基和吸附水)相互作用，环路由疏水链组成。这个环路是粒子凝聚的排斥力的来源。定量计算了环的三维体积、厚度和链段密度，以及金属氧化物表面的官能团密度和占据面积。还研究了颗粒的分散性与吸附构象的关系。吸附聚合物链的链段密度是粒子分散性好的关键因素。综上所述，通过探测高分子链的吸附构象，调节界面结构带来了复合材料的高功能性。

The dispersibility, the orientation of filled particle are quite important for the high performance of composite materials. These properties depend on the repulsive power (through osmotic pressure and entropic elasticity of polymer chain) of absorbed polymer layr on the particle, so the conformation of these adsorbed chains were investigated in this study. Monodispersed polymer with terminal functional group (by living anion polymerization), polymer with amino group (by radical polymerization) were synthesized through the precious polymerization technique. The adsorbed conformation was investigated through the techniques as follows : Surface Force Apparatus (purchased through the financial support from this grant (1995)), Atomic Force Microscopy (purchased through the financial support from this grant (1996)), Dynamic Light Scattering, Elipsometry, Surface Tension Apparatus, Electron Microscopy, Surface Force-surface Pressure Apparatus, Pheology Apparatus.The adsorbed conformation of polymer chain on silica, gamma-iron oxide can be expressed with so-called loop-point model, where polar functional group interacts with metal oxide surface (surface is covered with hydroxy group and adsorbed water) and the loop was consisted of hydrophobic chain. This loop is the origin of the repulsive force against coagulation of particles. Three dimensional bulkiness, thickness, and segment density of the loop, and functional group density, occupied area of one functional group on the metal oxide surface were quantified in this study. Relationship between the dispersibility of particles and the adsorbed conformation was also investigated. The segment density of the adsorbed polymer chains was found to be the key factor for the good dispersibility of particles. In conclusion, regulating the interfacial structure brought the high functionality of composite material by probing the adsorbed conformation of the polymer chain.