... style expansion boards have good performance of sound insulation, sound absorption, heat insulation and heat preservation. PVC expansion boards can ... high security. PVC expansion boards can resist damp, mildew and water, as well as quakeproof. PVC expansion boards are made ... at break, % 15-20, Shore Hardness, D type, 45-50 water absorption, % ≥1.5, Vicat softening point, 73-76 fire-retardant ...