PTSC WSR 3632 Wet Strength Resin PTSC WSR 3632 is a cationic polyamide wet strength resin supplied as an aqueous solution containing Approximate 12.5% solids. When applied under acidic or alkaline stock conditions, PTSC WSR 3632 will efficiently increase the wet strength properties of finished paper or paperboard products. Use and Application PTSC WSR 3632 resin is highly effective for developing wet strength in facial tissue, napkins, towels, carrier board, liquid packaging, bag paper, linerboard, medium, and other Speciality papers. PTSC WSR 3632 performs over a broad pH range of 4.0 – 9.0 (with best efficiency between 6.5 – 8.0) in the presence of normal papermaking additives. Typical furnish levels range from 0.2 to 0.75% (dry basis), which is dependent upon the wet strength level desired and the grade being manufactured. PTSC WSR 3632 can be added to either the thin or thick stock systems. Best results are achieved with sufficient random dilution and maximum available stock agitation at the point of addition. PTSC WSR 3632 should be added after rosin size and alum addition

The wet strength is not fully developed by the time a paper product reaches the end of a paper machine, and strength continues to develop as the paper is stored. The rate of curing is affected by the temperature and the length of time in contact with heat. The bonds that are eventually formed are not readily broken under either acid or slightly alkaline conditions, and the wet strength is therefore permanent. Whilst this can be an advantage in certain applications, it does make the paper or paperboard more difficult to disintegrate. However, the difficulties for the disintegration of WSR -treated paper have not been reported practically when the dosage level of WSR resin is below 4%.