... good quality of heat insulation and prese Plastic board extrusion line1. Free style expansion boards and co-extruding ... performance index of PVC free style expansion boards: item, unit, result, surface density, g/cm3 0.5-0.8 ... KJ/m2 8-15, item, unit, result, elongation at break, % 15-20, Shore Hardness, D type, 45-50 water absorption, % ... than 5 seconds PVC expansion plastic board extrusion line