High orientation structure in UHMWPE/BN composites continuously obtained by elongational flow field leading to superior thermal conductivity

作者：He, Guangjian; Lin, Zhihao; Yin, Xiaochun; Feng, Yanhong^*

来源：Journal of Applied Polymer Science, 2022, 139(29): e52640.

DOI：10.1002/app.52640

• composites
• polyolefins
• structure-property relationships
• thermal properties

Ultra-high-molecular-weight polyethylene/boron nitride (BN) composites have been continuously prepared successfully by eccentric rotor extruder (ERE) based on elongational flow. Optical microscopy (OM), scanning electron microscopy (SEM), x-ray diffraction (XRD), thermal conductivity test, heat-dissipation test, and tensile test were performed to investigate the orientation structure, thermal conductivity, mechanical properties, and insulation properties. The orientation factor and thermal conductivity of the composites prepared by ERE were 79.3 and 3.75 W center dot m(-1)center dot K-1, which were much higher than those of composites prepared with a torque mixer (14.7 and 2.73 W center dot m(-1)center dot K-1, respectively). OM and SEM showed that the BN sheets were in contact inside the composites and formed an efficient thermal conductivity network. Besides, the composites prepared by ERE had satisfactory mechanical and insulation properties (>10(13) omega center dot cm). This study provides experimental and theoretical guidance for industrial preparation of polymer/layered-filler functional composites.