How to improve the hardness of the core layer of PVC crust foaming board?
How to improve the hardness of the core layer of PVC crust foaming board? The surface hardness of foam products is usually high, but the hardness of core layer, namely foam layer, is low. How to improve the hardness of core layer One is to add less plasticizer, the other is to reduce foaming ratio and bubble pore size Secondly, the appropriate amount of calcium powder and the supplementary use