Two-step shape recovery in heating-responsive shape memory polytetrafluoroethylene and its thermally assisted self-healing

摘要

In this paper, the heating-responsive shape memory effect (SME) in commercial polytetrafluoroethylene (PTFE) programmed by means of tension and compression is investigated systematically. The focus is on the influence of the glass transition (T_g) and the melting transition (T_m) on the shape recovery performance. Two-step shape recovery upon heating to over the glass transition range and then the melting transition range is observed. The key parameters in programming, namely the programming temperature, programming strain and deformation method, are examined. In addition, we study the feasibility of utilizing the high melting temperature nature of PTFE as a high temperature shape memory polymer (SMP) and for thermally assisted self-healing.