SYNTHESIS OF MOLECULAR COMPOSITES NOVEL DENTAL MATERIALS

三大类牙科材料已被开发和使用， 牙科实践：（1）无机/陶瓷材料（例如汞合金和 硅酸盐水泥），（2）有机聚合物（例如聚丙烯酸酯树脂）和（3） 聚合物复合材料，其中填料与聚合物以 宏观层面。 所有这些材料，虽然成功地在某些 在一定程度上，它们在牙科应用中具有许多固有的缺陷。 提出了一类新的牙科材料，其共价和 将有机聚合物均匀地结合到无机网络中， 分子水平通过新出现的溶胶-凝胶法。 这些分子 复合材料将具有定制的硬度组合， 无机玻璃和有机聚合物的韧性。 由于有机 无机组分共价键合并均匀分布在 这些新材料，将不会有界面问题，存在于 传统的牙科复合材料。 在本方案中，选择聚丙烯酸酯-SiO2-TiO 2体系作为典型 初步研究的例子，以充分利用， 已建立的控制分子量的临床应用， 理想的端基，如-Si（OR）3，其在溶胶-凝胶中是反应性的 反应，将通过基团转移聚合方法合成 1983年由杜邦蓬特发明。 四种类型的遥爪聚合物将是 用一个、两个、三个/四个或更多个反应性-Si（OR）3基团合成。 然后将遥爪聚合物引入硅的混合物中， 和/或四烷氧基钛，然后B水解和交联 （致密化）导致新的分子复合材料。 将对这类新材料进行表征和测试。 取决于 无机组分与聚合组分的性质和比例， 应该具有上级的物理和化学性能如硬度， 韧性、对牙齿结构的粘附性、耐磨性和耐磨性， 稳定性等。

Three major classes of dental materials have been developed and used in dental practice: (1) inorganic/ceramic materials (e.g. amalgams and silicate cements), (2) organic polymers (e.g. polyacrylate resins) and (3) polymer composite materials in which fillers are mixed with a polymer at a macroscopic level. All of these materials, though succeeded in certain extent, have many inherent deficiencies in their dental applications. A novel class of dental materials is proposed, which covalently and uniformly incorporates organic polymers into an inorganic network at the molecular levels via a newly emerged sol-gel method. These molecular composite materials would have tailored combinations of the hardness of inorganic glasses and the toughness of organic polymers. Since the organic and inorganic components are covalently bonded and uniformly distributed in these new materials, there would be no interface problems as exist in the conventional dental composites. In this proposal, polyacrylates-SiO2-TiO2 systems are selected as typical examples for the initial studies with the view of taking advantage of well- established clinical applications of controlled molecular weights and desirable end groups such as -Si(OR)3, which is reactive in sol-gel reactions, will be synthesized by group-transfer polymerization method invented at Du Pont in 1983. Four types of telechelic polymers will be synthesized with one, two, three/four, or more reactive-Si(OR)3 groups. The telechelic polymers will then be introduced into the mixture of silicon and/or titanium tetraalkoxides followed b hydrolysis and crosslinking (densification) leading to the new molecular composite materials. This new class of materials will be characterized and tested. Depending on the nature and the ratio of the inorganic to the polymeric components, it should be superior in physical and chemical properties such as hardness, toughness, adhesion to tooth structure, resistance to wear and abrasion, stability, etc. over the existing dental materials.