Fan Long Fei, Huang Ya Nan, Rong Min Zhi, Zhang Ming Qiu, Chen Xudong
School of Textile Materials and Engineering, Wuyi University, Jiangmen, Guangdong 529020, People's Republic of China.
Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, GD HPPC Lab, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China.
ACS Macro Lett. 2019 Sep 17;8(9):1141-1146. doi: 10.1021/acsmacrolett.9b00467. Epub 2019 Aug 21.
Two simple methods are proposed to respectively impart external force-free reversible shape memory effect to commercial polyolefins: ultrahigh molecular weight polyethylene (UHMWPE) and polypropylene (PP). The key issues lie in the utilization of the partially entangled molecular chains of UHMWPE and the medium crystalline phases of PP as the reversible internal stress providers. The acquired reversible shape memory effect further proves to be applicable for assisting repeatedly self-healing of wider cracks. Compared to the conventional approaches, which used to introduce cross-linkages into the target materials, the present ones only need physical treatment, so that the valuable thermoplasticity of polyolefins is retained. This work can be regarded as an example of the concept "physically converting instead of chemically modifying" for the preparation of functional polymeric materials based on market available plastics.
提出了两种简单的方法，分别赋予商用聚烯烃——超高分子量聚乙烯（UHMWPE）和聚丙烯（PP）——外力自由可逆形状记忆效应。关键在于利用UHMWPE的部分缠结分子链和PP的中晶相作为可逆内应力的提供者。所获得的可逆形状记忆效应进一步证明适用于辅助更宽裂缝的反复自愈。与以往在目标材料中引入交联的传统方法相比，目前的方法仅需物理处理，从而保留了聚烯烃宝贵的热塑性。这项工作可被视为基于市售塑料制备功能高分子材料的“物理转化而非化学改性”概念的一个实例。
