To improve creep resistance of directional polytetrafluoroethylene (PTFE) films, epoxy grafted nano-SiO2 is mixed with PTFE powder before sintering and calender rolling. The aligned macromolecular chains (especiall...To improve creep resistance of directional polytetrafluoroethylene (PTFE) films, epoxy grafted nano-SiO2 is mixed with PTFE powder before sintering and calender rolling. The aligned macromolecular chains (especially those in amorphous region) of the composite films can be bundled up by the nanoparticles to share the applied stress together. In addition, incorporation of silica nanoparticles increases crystallinity of PTFE and favors microfibrillation of PTFE in the course of large deformation. As result, PTFE films exhibit lower creep strain and creep rate, and higher tensile strength and hardness. The work is believed to open an avenue for manufacturing high performance fluoropolymers by nano-inclusions.展开更多
基金financially supported by the National Natural Science Foundation of China (No.51173207)Sino-Hungarian Scientific and Technological Cooperation Project (No.2009DFA52660)+1 种基金Key projects of Guangdong Education Office (No.cxzd1101)Natural Science Foundation of Guangdong (Nos.2010B010800020,2011B090500004,2011BZ100051)
文摘To improve creep resistance of directional polytetrafluoroethylene (PTFE) films, epoxy grafted nano-SiO2 is mixed with PTFE powder before sintering and calender rolling. The aligned macromolecular chains (especially those in amorphous region) of the composite films can be bundled up by the nanoparticles to share the applied stress together. In addition, incorporation of silica nanoparticles increases crystallinity of PTFE and favors microfibrillation of PTFE in the course of large deformation. As result, PTFE films exhibit lower creep strain and creep rate, and higher tensile strength and hardness. The work is believed to open an avenue for manufacturing high performance fluoropolymers by nano-inclusions.