Studies of modification of HDPE and interfacial interaction of its composites with sericite
(2517–2522)Polymers for Advanced Technologies 22 #12 (2011)
Li et al ofNanjing University, China, functionalized high-density polyethylene (HDPE) with ultraviolet light and to improve the interfacial interaction of its composites with sericite in this study.  The oxygen-containing groups of CO, C-O, and C(O)O were quickly introduced onto molecular chains of HDPE by ultraviolet irradiation in ozone atmosphere and the contents of the introduced oxygen-containing groups increased with increasing the modification time. After modification, the molecular weight of the irradiated HDPE decreased and its distribution became wider. The irradiated HDPE in ozone was not crosslinked.  The dispersion of sericite in the matrix and the interfacial interaction of sericite with the matrix were markedly improved for the irradiated HDPE/sericite composites. As a result, the irradiated HDPE/sericite composites showed significantly increased tensile yield strength and notched impact strength.  (RDC 11/25/2011)

Effects of matrix molecular weight on structure and reinforcement of high density polyethylene/mica composites
(377-369)  Chinese Journal of Polymer Science 29, #3 (2011)
Chen et al of Sichuan University, China, studied three types of high-density polyethylene (HDPE) with different molecular weights (high, medium and low) to evaluate the influence of matrix molecular weight on the structure-property relation of injection-molded HDPE/mica composites through a combination of SEM, 2d-WAXS, DSC, DMA and tensile testing.  The transcrystallization of HDPE on the mica surface was observed and it exhibited strong matrix molecular weight dependence. Obvious transcrystalline structure was found in the composite with low molecular weight HDPE, whereas it was hard to be detected in the composites with increased HDPE molecular weight.  The best reinforcement effect in the composite with low molecular weight HDPE can be understood as mainly due to substantially improved interfacial adhesion between matrix and mica filler, which arises from the transcrystallization mechanism.  (RDC 5/16/2011)