南非采购需求：cas 9002-98-6，聚乙烯亚胺，聚乙烯亚胺制造商，医疗保健和家庭护理，有机化学

I'm looking for samples of PEI suitable for use in a paper machine, specifically the K3/K4 grades. The application involves drainage and retention aid, and I'm interested in options that are comparable to what I have used before. Additionally, I need a sample of PEI that can function as a coagulant for water treatment applications. If you could provide details on availability and specifications, that would be great! Thank you!