LIQUID CRYSTAL MONOMERS

液晶单体

• 批准号: 6443360
• 负责人: BARRY K NORLING
• 金额: $ 40.85万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6443360
• 关键词: biomaterial development /preparation; dental materials; liquid crystal

A major goal of restorative dentistry is the replacement of carious lesions with a material which most closely resembles the lost tissue, aesthetically and functionally. While Current resin composites posses desirable properties including aesthetics, wear resistance, mechanical strength and coefficient of thermal expansion approaching that of tooth structure, they undergo sufficient cure shrinkage to create interfacial stresses of such magnitude that marginal seals cannot be reliably maintained in large posterior restorations despite the tremendous gains made in dentin bonding in recent years. Our goal is to develop new resin composites which possess the mechanical and aesthetic properties of current resins, while greatly simplifying the task of bonding to eliminate marginal leakage. We base our goal on the observation that nematic liquid crystal (LC) monomers can polymerize to isotropic polymers. Our hypothesis is that appropriately selected liquid crystal monomers can be synthesized for use as matrix resins in dental restorative materials which possess- the desirable properties of current matrix resins while undergoing zero polymerization shrinkage. This hypothesis is based on the volume expansion which accompanies transformation from an ordered LC nematic structure to an isotropic solid. Specific Aim 1 will synthesize several candidate diacrylate and dimethacrylate monomers and characterize them as to mesophase transformation temperatures and polymerization shrinkages. Critical to this aim will be the development of monomers which are nematic LC at room temperature when pure, or when solvated by conventional comonomers, or when highly filled with nanofillers. Specific Aim 2 will develop model resin Composites based on the best LC monomer(s) from specific aim 1 and conventional silanized small particle barium glass fillers. Specific Aim 3 will develop model resin composites based on the best LC monomer(s)from specific aim 1 and hybrid tantalum oxide nanofillers developed in Project 1, Nanofiller Development. The resin composites developed under specific aims 2 and 3 will be completely characterized for critical performance properties including in vitro and in vivo.

修复牙科的一个主要目标是替换龋齿 损伤的材料与丢失的组织最相似， 美学和功能上。虽然目前的树脂复合材料 所需的性能，包括美观性、耐磨性、机械性能 强度和热膨胀系数接近 牙齿结构，它们经历足够的固化收缩， 界面应力的大小使得边缘密封不能 可靠地保持在大的后脱位中， 近年来在牙本质粘接方面取得了巨大的进展。我们的目标 是开发新的树脂复合材料， 目前树脂的美学特性，同时大大简化了 粘接的任务，以消除边缘泄漏。 我们的目标是 已经观察到，可聚合液晶（LC）单体可以 各向同性聚合物。我们的假设是 可以合成适当选择的液晶单体 用作牙科修复材料中的基质树脂， 当前基质树脂在经历零的同时具有理想的性能 聚合收缩这个假设是基于 伴随着从有序LC变换的扩展 从非对称结构转变为各向同性固体。具体目标1将 合成几种候选二丙烯酸酯和二甲基丙烯酸酯单体 并将它们表征为中间相转变温度 和聚合收缩。实现这一目标的关键是 开发在室温下可降解的单体 当纯的或当通过常规方法溶剂化时， 共聚单体，或者当高度填充有纳米填料时。具体目标2 将开发基于最佳LC的模型树脂复合材料 来自具体目标1的单体和常规硅烷化小单体 颗粒钡玻璃填料。具体目标3将开发模型树脂 基于来自具体目标1的最佳LC单体的复合物，以及 在项目1中开发的混合氧化钽纳米填料，纳米填料 发展在特定目标下开发的树脂复合材料 2和3将完全表征关键性能 包括体外和体内的性质。