Low Shrinkage Dental Resins from SOC Oligomers

描述（由申请人提供）：聚合收缩率和 伴随的压力发展一直是重要的限制因素， 牙科聚合物的性能。体积收缩，导致一些 度从所有传统的聚合工艺，是负责 边缘间隙形成、微裂纹和牙齿弯曲。底切型腔 制备，复杂的多步键合预处理和应用， 在增量层的让步都是牙医必须作出的让步， 处理聚合收缩问题。短消息相关 聚合收缩在多种聚合物应用中得到反映 因此，这里实现的实际解决方案 潜力是非常深远的。这次调查的重点是 螺环原碳酸酯（SOC）的开环聚合， 体积膨胀通常为2.5%至3.5%。尽管金额不小 自2001年开始实施以来，在这一领域取得了一些成就。 在20世纪70年代，对这一点的基本理解仍然存在一些明显的差距。 独特的聚合工艺。知识库中的这些缺陷是 在很大程度上要对在努力中遇到的困难负责， 以将SOC单体与其它单体系统整合。因此，这一目标 项目是：1）确定SOC光聚合动力学与有效的 阳离子引发剂体系; 2）鉴定由以下物质产生的聚合物结构： 模型SOC单体的阳离子光聚合; 3）开发实用的 进行阳离子开环的多官能SOC低聚物 通过交联形成聚合;和4）证明了 阳离子/自由基、可见光固化树脂和复合材料， 具有最小收缩和应力发展的混合网络聚合物。在 最后，对复杂SOC开环的基本认识 光聚合方法，这还没有得到这一点，将 沿着出现了一种实用阳离子/自由基双固化树脂体系， 将仅产生交联聚合物。当前的应用程序提供了一个 SOC开发的另一种方法，该方法承认以下缺陷： 已经阻止了这项技术，并提供了补救措施， 潜在的负面影响。从混合材料中获得的信息 将直接应用于改进的牙科清洁剂的开发 具有最小的收缩和应力。

DESCRIPTION (provided by applicant): Polymerization shrinkage and the accompanying stress development have been significant limiting factors in the performance of Dental polymers. The volumetric shrinkage, which results in some degree from all conventional polymerization processes, is responsible for marginal gap formation, microcracking and tooth flexure. Undercut cavity preparations, complicated multistep bonding pretreatments and application of restoratives in incremental layers are all concessions the Dentist must make to deal with the polymerization shrinkage issue. Shortcomings related to polymerization shrinkage are echoed in a wide variety of polymer applications that extend beyond Dentistry; therefore, practical solutions achieved here have the potential to be very far-reaching. This investigation focuses on the double ring-opening polymerization of Spiro-orthocarbonates (SOC), which occurs with volumetric expansions typically of 2.5 to 3.5 percent. While substantial accomplishments have been made in this field since its initial introduction in the 1970s, there remain some glaring gaps in the basic understanding of this unique polymerization process. These deficiencies in the knowledge base are largely responsible for the difficulties that have been encountered in efforts to integrate SOC monomers with other monomer systems. Thus, the goals of this project are to: 1) determine SOC photopolymerization kinetics with efficient cationic initiator systems; 2) identify the polymeric structures generated by cationic photopolymerization of model SOC monomers; 3) develop a practical multifunctional SOC oligomer that undergoes cationic ring-opening polymerization via cross-link formation; and 4) demonstrate the potential of cationic/free radical, visible light cured resins and composites that produce hybrid network polymers with minimal shrinkage and stress development. In the end, a fundamental understanding of the complex SOC ring-opening photopolymerization process, which has not been available to this point, will emerge along with a practical cationic/free radical dual cure resin system that will produce only cross-linked polymers. The current application offers an alternative approach to SOC development that acknowledges the deficiencies that have held back this technology and provides remedies that will address each of the potential negative areas. The information gained on the hybrid materials will be directly applicable to the development of improved Dental restoratives with minimal shrinkage and stress.