SBIR Phase I: Liquid Crystalline Thermoset (LCT) Adhesives for High-Temperature Applications

* 96-60674霍伊特 该小型企业创新研究第一阶段项目旨在开发具有适用于航空航天工业应用的热和机械性能的粘合剂。对这些材料的理想要求相当严格。该材料必须具有高强度和高断裂韧性、良好的耐化学性和在150 C-370 C范围内的长期热稳定性。虽然在高温粘合剂方面有大量的研究工作，但目前可用的材料远远达不到理想的要求。我们建议调查液晶热水瓶（LCT）系统适用于在高温，高性能的环境中使用的粘合剂。LCT，像它们的液晶聚合物（LOP）类似物一样，预期在热性能和机械性能以及耐化学性方面提供比它们的非液晶对应物显著的增强。此外，液晶材料的固有低熔体粘度在粘合剂应用中应带来若干加工优点。所研究的材料通常将在可熔融加工或热致LCT的已知实例上建模。将根据行业标准选择反应性端基;将测试一些专有端基。第一阶段的主要产品是第二阶段系统优化和扩展粘结测试所需的数据。这些数据还应提供有关LCT和一般粘合剂的结构-性能关系的信息。 如果这项工作取得成功，将实现用于高温应用的新型粘合剂。虽然这些材料的应用最初集中在航空航天工业，但也有可能用于其他领域，如桥梁和高速运输系统的轻质结构材料。 *** ??

*** 96-60674 Hoyt This Small Business Innovation Research Phase I project aims to develop adhesives with thermal and mechanical properties suitable for applications in the aerospace industry. The ideal requirements for these materials are rather stringent. The materials must exhibit high strength and high fracture toughness, good chemical resistance and long-term thermal stability somewhere in the range 150 C-370 C. While there is a significant research effort in high-temperature adhesives, currently available materials fall well short of the ideal requirements. We propose to investigate liquid crystalline thermoses (LCT) systems to be applied as adhesives suitable for use in high-temperature, high-performance environments. LCTs, like their liquid crystalline polymer (LOP) analogues, are expected to offer significant enhancements in thermal and mechanical properties and chemical resistance over their non-liquid crystalline counterparts. In addition, the inherent low melt viscosity of liquid crystalline materials should bring about several processing advantages in adhesive applications. The materials investigated will be generally modeled on known examples of melt-processable or thermotropic LCTs. Reactive endgroups will be chosen based on standards in the industry; some proprietary endgroups will be tested. The major product of Phase I is the data required for system optimization and extended bond testing in Phase II. These data should also provide information on structure-property relationships in LCTs and for adhesives in general. If this work is successful, a new type of adhesive for high-temperature applications should be realized. While the application of these materials is initially focused on the aerospace industry, there is potential for use in other areas such as lightweight structural materials for bridges and in high speed transportation systems. *** ??