Properties of brominated butyl rubber/polyethylene supercritical foaming materials

Abstract

Brominated butyl rubber (BIIR) and polyethylene (PE) were used as the matrix to prepare BIIR/PE blend foams by supercritical nitrogen gas fluid foaming technology, and the effects of BIIR amount on density, foaming ratio, hardness, resilience, compression set, microstructure and thermal conductivity of the foam were investigated. The results showed that the foam density increased from 0.075 g/cm3 to 0.092 g/cm3 and foaming ratio decreased slightly with the increase of BIIR amount from 0 to 40 phr (mass); the impact rebound performance was significantly enhanced, while the hardness and compression set decreased; the cell sizes reduced and uniformity of the cell improved. The thermal conductivity could be reduced to 0.046 61 W/(m·K) at the best, and the thermal insulation properties of BIIR/PE blends foams had been significantly improved.

Keywords

• brominated butyl rubber
• polyethylene
• supercritical foaming
• cellular structure
• physical and mechanical property
• thermal conductivity