PVC（硬胶）比重1.38-1.41PVC（软胶）比重1.19-1.35PET比重1.29-1.41PP比重0.85-0.92我再想想其它比较常用的像PC比重1.20-1.22PPS比重1.28-1.32PBT比重1.30-1.38
