Development of the composite resin with less amount of the shrinkage

为了获得关于哪些参数控制硬化过程中实验填充树脂的收缩的信息，研究了实验填充树脂的体积收缩和线性收缩。讨论了收缩应力与这些数据之间的相关性，填充树脂的体积收缩与填料含量有关。相反，即使增加填料含量，线收缩也不是体积收缩的1/3。当长度小于5 mm时，线收缩率增大，线收缩率增大到体积收缩率的3倍以上，接近体积收缩率的1/3。线收缩的大小因型腔的大小和类型而异，即使体积收缩变小，填充树脂的收缩应力也会变大，直到填料含量为60%。所合成的二甲基丙烯酸酯单体的体积收缩率与市售的二甲基丙烯酸酯单体的体积收缩率相当，可以进行环聚合反应。其次，研究了衬层水泥对填充树脂收缩应力的影响。混凝土衬砌的收缩应力仅为未衬砌时的1/2。采用0.5-1.5mm的衬砌水泥，减小了收缩应力。

In order to obtain information concerning which parameters control the shrinkage of the experimental filled resin during hardening, the volumetric shrinkage and the linear shrinkage of the experimental filled resin were investigated. The correlation between the shrinkage stress and these datas was discussed.The volumetric shrinkage of the filled resin is dependent on the filler content. Contrary, the linear shrinkage is not 1/3 of the volumetric shrinkage even if the filler content was increased. However, when the length become shorter less than 5 mm, the linear shrinkage become larger and it's value become above 3 times, and approximates to 1/3 of the volumetric shrinkage. The magnitude of the linear shrinkage is different by the size and type of the cavity.The shrinkage stress of the filled resin become larger until the filler content is 60 % even if the volumetric shrinkage become smaller. The volumetric shrinkage of the synthesized di-methacrylate monomer which the cyclopolimerization is possible is pretty similar to that of commercial dimethacrylate monomers.Next, the effect of the lining cement on the shrinkage stress of the filled resin was investigated. The shrinkage stress become 1/2 of that obtained without a lining cement. The application of the lining cement, 0.5-1.5mm reduces the shrinkage stress.