Effects of nano TiO2 on the light reflectivity, morphology, and rheological behavior of LLDPE‐glass bead composites

Abstract

AbstractHeat‐shield composites based on linear low density polyethylene (LLDPE) filled with micro‐hollow glass beads (HGB) and TiO2 nanoparticles were prepared through melt compounding. Two kinds of LLDPE were used as the matrix of these composites with a fixed weight ratio of 60 : 40. HGB loadings were fixed at 28 wt % of LLDPE matrix while TiO2 content varied between 8 and 28 wt % of LLDPE matrix. Interestingly, the results show with addition of TiO2 to LLDPE‐HGB composites, both the light reflectivity and the flow ability of composites show great enhancement. Especially when the TiO2 loading is 14 wt % of LLDPE, UV, and infrared reflectivity of the composites are more than 90%, showing a optimal heat‐shielding performance, and the rheological responses including the storage modulus, G′ and the complex viscosities, |η*| of this composite are the lowest among all LLDPE/HGB composites. When TiO2 content is more than 14 wt %; however, ultraviolet radiation resistance is almost unchanged while that two dynamic rheological parameters increase gradually. It is proposed that the TiO2 loading of 14 wt % should be taken as the optimal value of a light reflectivity in LLDPE matrix, which is helpful in improving the processing ability by reduction in melt viscosity. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012