Study on novel composite resin with a low shrinking force during hardening

1. 设计了用交联单体在乙醇溶液中聚合制备微交联聚合物颗粒的新方法，并对其聚合机理进行了研究。将直径为0.5 μ m的交联聚合物颗粒与微球二氧化硅颗粒（MF）混合。采用该混合填料制备了热固化型树脂。硬化后，测定其磨损损失。采用上述方法设计了含MF的交联聚合物微胶囊颗粒（MCPF）。以MCPF和MF为填料制备了自固化型复合树脂，并对其硬化力学性能进行了测定。以MCPF、不规则二氧化硅和球状二氧化硅为填料，制备了四种自固化型复合树脂。用去年研制的树脂硬化收缩力测量仪对复合树脂硬化收缩力进行了测量。研究了硅填料的形状、尺寸和含量对复合树脂收缩力的影响。5-1不规则硅基复合树脂的收缩力比球状硅基复合树脂的收缩力大。5-2球状二氧化硅颗粒的含量高于不规则二氧化硅颗粒作为填料。收缩力随二氧化硅含量的增加而增大。5-3二氧化硅粒径越大，收缩力越小。5-4树脂凝固时间越晚，收缩力越小。5-5利用上述数据，讨论了复合树脂在硬化过程中收缩力的控制参数。

1. Novel method was designed to obtain the micro cross-linked polymer particle using solution polymerization of cross-linking monomer in ethanol, and it's polymerization mechanism was clarified.2. The cross-linked polymer particle whose diameter is 0.5mum, was mixed with the micro globule silica particle (MF). The resin of a heat-cured type was prepared using the mixed filler. After hardening, it's abrasion loss was measured.3. The micro capsule particle (MCPF) of the cross-linked polymer containing the MF was designed using the method as mentioned above. The composite resin of a self-cured type was prepared using MCPF and MF as filler, and the mechanical properties of it's hardening was measured.4. Four kinds of composite resins of a self-cured type was prepared using MCPF, an irregular silica or a globule silica as filler. The shrinking force of the composite resin during hardening was measured with the apparatus which was prepared last year to measure the shrinking force of a resin during hardening.5. The effect of the shape, the size and the content of silica filler in composite resin on the shrinking force was investigated.5-1 The shrinking force of the composite resin based on an irregular silica is larger than that based on a globule silica.5-2 The content of a globule silica particle is higher than an irregular silica particle as filler. However, the shrinking force increases with increasing the silica content.5-3 As the size of silica is larger, the shrinking force become smaller.5-4 As the setting time of resin become later, the shrinking force become smaller.5-5 The parameter to control the shrinking force of composite resin during hardening is discussed using the datas as mentioned above.