Study on the Thermal Conductive Polyoxymethylene/Graphite Composites

The thermal conductive composites of polyoxymethylene (POM)/graphite were prepared through four intercalation methods, including melt (MI), solution (SM), pan milling (SMI), and in situ intercalation (IM). For the purpose of improving the interfacial compatibility of POM/graphite, realizing the exfoliation and nano-dispersion of graphite in POM matrix, the effect of the type and the content of the graphite, the nature of the coupling agents used in graphite modification on the properties of the composites was studied. The results showed that the thermal conductive properties of POM were improved remarkably from the value of 0.36 W/(m K) for neat POM to the value of 1.15 W/(m K) in presence of 30 wt % graphite, and the composites filled with the coupling agent T-I or T-2 surface-modified colloidal graphite displayed better thermal conductivity. The degree of layers exfoliation of the graphite was enhanced in the order of MI, SM, SMI, and IM. And the composites prepared by SM, SMI, and IM methods presented much more decreased size, more narrow size distribution, thinner overlapped sheets, and better dispersion of the graphite than that prepared by MI method. (C) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 111:759-767, 2009