Polyamide Epichlorohydrin (PAE) CAS 68583-79-9

What PAE Wet Strength Resin Does

PAE is the standard resin for making paper stay strong after it gets wet. The liquid carries positive charge, so it clings to cellulose fibers in the wet end, and the heat of the dryer cures it into a water-insoluble network bonded to the fibers. That cure is permanent: the sheet keeps its wet tensile strength through repeated wetting, unlike temporary wet strength additives that dissolve on rewet. It cures under neutral to slightly alkaline conditions and contains no free formaldehyde, which is what puts it ahead of older urea and melamine formaldehyde resins for tissue and food contact grades.

Wet Strength vs Sizing: Where PAE Fits

Wet strength and sizing are easy to confuse because both deal with water, but they answer different questions. Sizing, typically from AKD wax, slows water from soaking into the sheet. Wet strength from PAE keeps the sheet from falling apart once it is wet. Most grades that meet real-world liquid exposure, such as cup stock, kitchen towel and wet wipe base, use both, and the two are fully compatible in the same neutral furnish. PAE also adds a modest dry strength and retention boost on the side.

Papers That Need PAE

• Tissue and sanitary paper. Facial tissue, toilet paper, napkins and wet wipe base gain wet tensile strength without turning stiff or losing softness.
• Food contact paper and board. Cups, food boxes and baking paper hold wet burst strength at approved dosage, with no formaldehyde release.
• Industrial and specialty paper. Filter paper, wallpaper, labels and packaging board keep their ply bond and shape in humid conditions, and PAE helps recycled furnishes recover lost strength.

25% Solids Grade Specifications

Handling, Packaging and Ordering

• Keep drums and IBCs sealed at 5 to 30 °C, out of frost and direct sun. Freezing destabilizes the resin, and strong alkalis stored nearby can trigger premature crosslinking inside the drum.
• The liquid is non-hazardous for normal ocean and land transport. Avoid eye and prolonged skin contact, wear gloves and goggles, and do not flush undiluted product into drains.
• Packaging: 25 kg and 200 kg plastic drums, 1000 kg IBCs, with diluted ready-to-use grades on request. COA, TDS and SDS come with every order, samples are available, and quotes go out within one working day. It pairs in the same neutral furnish with AKD Wax CAS 144245-85-2 and Cationic Starch CAS 56780-58-6.

FAQ

Q: How is PAE different from melamine formaldehyde resin?

A: PAE is formaldehyde-free and cures at neutral pH; MF costs less but releases formaldehyde.

Q: What PAE dosage is typical?

A: Mostly 0.5 to 2.0% on dry fiber, set by target wet strength, furnish and the machine.

Q: Is the wet strength permanent?

A: Yes. Cured PAE bonds to cellulose and stays insoluble through repeated wet and dry cycles.