Preparation of PTFE/graphene nanocomposites by compression moulding and free sintering: A guideline

摘要

This work was aimed at preparing polytetrafluoroethylene (PTFE) nanocomposites filled with graphene nanoplatelets and investigating how the graphene nanoplatelets and the preparation techniques influenced the physical properties. Graphene was incorporated up to 4 vol % of the total PTFE system by dry and solvent assisted blending. The powder compaction was evaluated using the Kawakita/Ludde model to describe the compressibility of the powder blends. The nanocomposite billets were prepared using cold compression moulding by applying preform pressures between 12.7 and 140 MPa and the preform billets were sintered at 380 degrees C using a specific sintering cycle. The changes in the physical dimensions, billet mass, density, and void content of the billets, pre and post sintering, were analyzed with experimental design to evaluate the influence of the precompaction pressure and graphene loading. From the evaluation it was concluded that the ideal compaction pressure was at 12.7 MPa and the solvent assisted blending was superior to the mechanical blending method. Furthermore, the compression creep tests confirmed the ideal processing temperature and graphene loading range to improve the mechanical properties. (c) 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43369.