GOALI: Mechanical Activation of Amorphous Shape Memory Polymers

GOALI：无定形形状记忆聚合物的机械激活

• 批准号: 1130358
• 负责人: Thao Nguyen
• 金额: $ 29.8万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1130358&HistoricalAwards=false
• 关键词: GOALI; Mechanical; Activation; Amorphous; Shape

The research objective of this Grant Opportunity for Academic Liaison with Industry (GOALI) project is to elucidate the mechanisms controlling the performance of shape memory polymers during mechanical activation. Amorphous shape memory polymers can be programmed to store a temporary shape by applying deformation and cooling below the glass transition temperature. The material recovers the permanent shape when reheated above the transition temperature. The polymer structure can be tailored to meet a broad range of mechanical and biological requirements. This makes them attractive for applications in the biomedical device industry; yet they have not gained wider acceptance because of their slow recovery times. In mechanical activation, mechanical work is applied in addition to temperature to accelerate shape recovery. The research will investigate the importance of two mechanisms, molecular orientation and structural relaxation, on the force requirements for mechanical activation. The effect of shape memory programming conditions and physical aging on mechanical behavior will be measured. Constitutive models will be developed to investigate the effect of material properties and temperature and loading conditions on mechanical activation.The research will enable the development of more precise programming and more efficient manufacturing strategies for mechanically activated devices. The developed models will help to characterize the safety and performance of these devices throughout their intended shelf life, which can lead to a wider acceptance in the biomedical device industry. Student researchers will gain industry experience through summer internships at a leading company for shape memory polymer medical devices. The research will be integrated into courses to include the mechanics of smart polymers.

该学术与工业联络资助机会 (GOALI) 项目的研究目标是阐明在机械激活过程中控制形状记忆聚合物性能的机制。 无定形形状记忆聚合物可以通过施加变形和低于玻璃化转变温度的冷却来存储临时形状。 当重新加热到转变温度以上时，材料会恢复永久形状。聚合物结构可以定制以满足广泛的机械和生物要求。 这使得它们对于生物医学设备行业的应用具有吸引力；但由于恢复时间缓慢，它们尚未获得更广泛的接受。 在机械活化中，除了温度之外还应用机械功来加速形状恢复。该研究将研究分子取向和结构松弛这两种机制对机械激活的力要求的重要性。 将测量形状记忆编程条件和物理老化对机械行为的影响。将开发本构模型来研究材料特性以及温度和负载条件对机械激活的影响。该研究将为机械激活设备开发更精确的编程和更有效的制造策略。 开发的模型将有助于表征这些设备在其预期保质期内的安全性和性能，这可以导致生物医​​学设备行业更广泛的接受。学生研究人员将通过在形状记忆聚合物医疗设备领先公司的暑期实习获得行业经验。 该研究将被纳入课程中，包括智能聚合物的力学。