Quasi-static and dynamic characterization of polyurea microspheres reinforced polyurea matrix composite
Quasi-static and dynamic characterization of polyurea microspheres reinforced polyurea matrix composite
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DOI：
10.1016/j.mtcomm.2020.101464
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发表时间：
2020-12-01
影响因子：
3.8
通讯作者：
Youssef, George
中科院分区：
文献类型：
--
作者：
Do, Sophia;Stepp, Sophia;Youssef, George
聚合物基复合材料目前在航空航天、汽车和生物医学工业中具有广泛的应用。这类材料的比强度和刚度可以很容易地设计;然而，增强的强度和刚度高度依赖于增强体和基质之间的界面结合的质量。因此，本研究的目的是合成和表征由聚脲微球增强的聚脲基复合材料，以减少机械失配并改善结合。对于该复合材料，选择由Versalink（R）P1000和Isonate（R）143 L形成的超粘弹性聚脲，因为其具有上级耐湿性以及优异的热和冲击缓解性能。从微观尺度的机械表征，复合材料显示出23%的弹性模量增加相比，散装对应物。作为准静态力学表征的结果，发现复合材料和纯聚脲之间的弹性模量相当，但屈服应力增加，应力-应变曲线下的面积减少，以及失效时的应变损失。动态力学测试表明，复合材料和纯样品在玻璃化转变（T-g）以上的时间依赖性响应相当，而在T-g以下显示差异。
Polymer matrix composites currently have a wide range of applications in the aerospace, automotive, and biomedical industries. The specific strength and stiffness of this class of materials can easily be engineered; however, the enhanced strength and stiffness are highly dependent on the quality of the interfacial bonding between the reinforcement and matrix. It is thus the aim of this research to synthesize and characterize a polyurea matrix composite that is reinforced by polyurea microspheres to reduce the mechanical mismatch and improve bonding. For this composite, a hyper-viscoelastic polyurea formed from Versalink (R) P1000 and Isonate (R) 143 L, was chosen for its superior moisture resistance, and excellent thermal and impact mitigation properties. From the micro-scale mechanical characterization, the composite displayed a 23 % increase in elastic modulus compared to the bulk counterpart. As a result of the quasi-static mechanical characterization, it was found that the elastic moduli were comparable between the composite and the neat polyurea, but showed an increase in yield stress and decrease in the area under the stress-strain curve as well as the loss of strain at failure. Dynamic mechanical testing indicated the comparable time-dependent response of the composite and neat samples above glass transition (T-g), while displaying a difference below T-g.