Improved balance between dimensional stability, mechanical properties and processability of linear low density polyethylene for rotational molding

Abstract The linear low density polyethylene (LLDPE) products made by rotational molding (RM) usually involve two main problems of poor dimensional stability and insufficient mechanical properties. Although the decline in thermal expansion coefficient and rise in mechanical strength can be attained by filling with inorganic particles, the melt fluidity of LLDPE, which is of great importance for RM, would be significantly reduced. In this study, a combination of crosslinker low‐temperature blending and partial chemical crosslinking strategy is employed to enhance the dimensional stability and mechanical properties of LLDPE without sacrificing the melt fluidity. The structure–property relationships in the crosslinked specimens are analyzed based on X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and dielectric spectrometry. The results show that our simple, low‐cost and universal strategy not only contributes to a better dimensional stability and significantly improved mechanical properties, but also endow the samples with promising processability and thermal stability.