Morphology and physical properties of composite foams based on low‐density polyethylene and ground tire rubber

Low‐density polyethylene (LDPE)/(ground tire rubber) (GTR) composite foams with an average cell size smaller than 100 µm were produced by compression molding. The effects of the mechanochemical pretreatment of the LDPE/GTR blends and their GTR content on the cell morphology and physical properties were investigated. The results indicated that the pretreatment of LDPE/GTR blends by using a pan‐mill type of mechanochemical reactor made in our laboratory improved the dispersion state and thereby enhanced the foamability of the blends. The average cell size of the composite foams decreased from 64.0 to 42.3 µm with an increase in GTR content from 0 to 50 phr (parts by weight per hundred parts of resin). Moreover, the addition of 20–40 phr of GTR into the LDPE foams increased their rebound resistance and decreased their compression set. J. VINYL ADDIT. TECHNOL., 19:105–112, 2013.