Presssure pipe does not typically use impact modifiers, the PVC resin is tough enough. Pressure pipe can have 0-5 phr of fine particle size carbonate is some times used in formulations for lower cost along w/a process aid to ease extrusion. DWV pipe has a bit of modifier; 2-3 phr of impact modifier and from 10-40 phr of fine particle size calcium carbonaate are used in some formulations. Careful w/ CPE as a modifier, over work it and you lose impact. The CPE addition should allow your formulation to tolerate more filler than a non-impact modified compound w/ little strength loss.
Yes,I agree with Mr.Len's words,He is right,he told all of what I want to say..and of course,CPE is an impact modifier,and it can improve the toughness of PVC rigid product,but if you use more CPE,you must add more CaCO3,and if you only add more CPE,the Rigid product will be soft and will be not hard enough to face the pressure.
So when we use the CPE,we must do more test to find the moderate point,that can make the filler like CaCO3 add more,and the PVC product can get good toughness also..
Edited by Will Call