Ultra-high molecular weight polyethylene (UHMWPE) is a very attractive polymer employed as a high performance material, while filler-reinforced composites have demonstrated its feasibility in various applications. Melt-mixing in an extruder is a key process in the development of polymer nanocomposites. Due to its high melt viscosity, dispersion of fillers is considered as a challenge in UHMWPE nanocomposites preparation process. In this work, we have prepared graphite-filled UHMWPE nanocomposites using a novel octa-screw melt kneading extruder. The engineering properties as well as the morphology of kneaded nanocomposites were characterized using tensile tester, friction and wear tester, scanning electron microscopy, optical profilemeter, polarized optical microscope, thermogravimetric analysis, differential scanning calorimetry, etc. The experimental results suggested good dispersion of graphite in the UHMWPE nanocomposites, demonstrating the excellent capability of the octa-screw extruder in compounding the graphite-filled nanocomposites. The yield strengths of the nanocomposites increase by 10% (from 21.6 MPa to 23.8 MPa) with the addition of 2% graphite. When the filler percentage was increased to 20%, the yield strengths improved from 21.6 to 27.4 MPa (an increase of 26.8%) for the graphite-filled composites. Furthermore, the crystallinity of UHMWPE nanocomposites increased with the content of graphite fillers, while the pyrolysis temperature of the composites increased with the content of graphite fillers.
Funding: This study was supported by JSPS KAKENHI for Scientific Research on Innovative Areas “MFS Materials Science (Grant Numbers JP18H05483), and JSPS KAKENHI Grant Numbers JP16K06740”.
 Huang G, Ni Z, Chen G, Zhao Y. Int. J. Polym. Sci. 2016, 2016, 1–9.Search in Google Scholar
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