IMPROVED PREVENTIVE/RESTORATIVE RESINS AND COMPOSITES

改进的预防/修复树脂和复合材料

• 批准号: 6983252
• 负责人: SABINE H DICKENS
• 金额: $ 18.75万
• 依托单位: AMERICAN DENTAL ASSOCIATION FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-07 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6983252
• 关键词: biomaterial development /preparation; biomaterial evaluation; chemical structure; chemical synthesis; composite resins; computer simulation; dental materials; human tissue; hydropathy; liquid chromatography mass spectrometry; model design /development; monomer; nuclear magnetic resonance spectroscopy; restorative dentistry; thin layer chromatography

DESCRIPTION: There is still a need to develop new Dental monomers to overcome the shortcomings that limit the useable lifetime of resin based Dental restorations. Current day resin-based Dental composites have clinical performance deficiencies that include inadequate resistance to wear, secondary caries as a result of marginal leakage, and hydrolytic breakdown of filler-resin interface. Here it is proposed to correlate the chemical core structure of a polymerizable monomer to selected properties in the resulting Dental material. For example, dimethacrylate monomers with rigid aromatic and flexible aliphatic groups will result in polymers with increased toughness, a desired property for improving wear resistance in Dental composites. In this exploratory application we propose to synthesize aromatic acid monomers with varying numbers of rigid aromatic groups and flexible ether linkages interspaced between them. We will then study the influence of these chemical structures on the mechanical and physical properties of the resulting polymers (Aim 1). Analytical methods such as TLC, LC-MS, FTIR, NMR, and others will be used as necessary. Fracture toughness, conversion, water sorption and the viscoelastic properties and glass transition temperature of the polymers will be determined. Computer modeling of the monomers will be carried out to build an empirical correlation between the energy of rotation about the ether linkage and the resulting toughness of the polymer from the synthesized monomers (Aim 2). Molecular features such as the number and bulkiness of the aromatic groups can increase the energy of rotation due to steric hindrances and electronic interactions. The study will also include calculating the resulting energies from changing the ether linkage to e.g., a perfluoro-isopropylidene, carbonyl, or sulfone (-SO2-) group and others. This modeling may indicate which intramolecular features of the monomer are important for controlling the toughness of the polymer. The data gathered in these experiments will serve to support a larger R01 grant application with the long-term objectives of developing improved durable materials for adhesives and adhesive composites.

描述：仍然需要开发新的牙科单体来克服限制基于树脂的牙科修复体可用寿命的缺点。当前的基于树脂的牙科复合材料具有临床性能缺陷，包括对磨损的抵抗力不足，由于边缘泄漏而导致的次生龋齿以及填充 - 固定界面的水解分解。在这里，提议将可聚合单体的化学核心结构与所得牙科材料中选定的特性相关联。例如，具有刚性芳香和柔性脂肪族基团的二甲基丙烯酸酯单体将导致韧性增加的聚合物，这是提高牙科复合材料耐磨性的所需特性。在此探索性应用中，我们建议合成具有不同数量的刚性芳香族组和柔性以太链接的芳族酸单体。然后，我们将研究这些化学结构对所得聚合物的机械和物理特性的影响（AIM 1）。必须使用分析方法，例如TLC，LC-MS，FTIR，NMR等。将确定聚合物的断裂韧性，转换，吸附以及粘弹性和玻璃过渡温度。将进行单体的计算机建模，以在旋转能量围绕醚键的旋转能量与合成单体的聚合物产生的韧性之间建立经验相关性（AIM 2）。分子特征（例如芳族基团的数量和体积）可以增加由于空间的阻碍和电子相互作用而引起的旋转能量。该研究还将包括从将醚连接更改为例如全氟异丙基，羰基或磺基（-SO2-）组等的醚连接来计算所得能量。该建模可能表明单体的分子内特征对于控制聚合物的韧性很重要。这些实验中收集的数据将有助于支持更大的R01赠款应用，其长期目标是为粘合剂和粘合剂复合材料开发改进的耐用材料。