Non Fluorinated Durable Water Repellent Wet Processing Specifications
Non-fluorinated DWR wet processing requires bath pH 4.0-5.5, WPU control, and core cure temperatures of 150-170°C with crosslinkers to pass 10 ppm fluorine limits.
Carbodiimide Crosslinker
Polymer Modifier
Chemical additives that crosslink polymer chains improve the wash fastness and mechanical resistance of polyurethane and acrylic coatings applied to technical fabrics. Inserting a carbodiimide crosslinker into the polymer dispersion creates covalent bonds with the carboxyl groups of the resin during the drying and curing stages of textile finishing. This modification enhances the adhesion of the coating to the synthetic fibers of the base fabric.
Chemical Reaction
The molecular structure of this compound allows it to react with carboxylic acid groups at relatively low curing temperatures, forming stable urea derivatives. When the water in the finish formulation evaporates under heat, the reactive carbodiimide groups secure the polymer network without releasing harmful volatile organic compounds or byproducts. This low-temperature reaction makes the chemistry highly compatible with heat-sensitive fabrics like nylon and polyester blends.
Performance Benefit
Garments coated with finishes utilizing this crosslinking chemistry exhibit superior resistance to abrasion, home laundering, and chemical cleaning.
Process Restriction
Finishing mills must carefully monitor the pot life of the formulated coating batch because the crosslinking reaction begins as soon as the additive is mixed with the resin. If the mixture is left for too long before application, the viscosity increases, leading to uneven coating thickness or clogged application rollers on the finishing line. Consequently, operators must mix only the quantity required for immediate production and thoroughly clean the equipment after each run to prevent resin buildup.
This operational discipline ensures consistent fabric performance across the entire production lot.
Quantifying Sorption Hysteresis and Crosslinker Hydrolysis in Multi Layer Textile Laminates
Quantitative evaluation of sorption hysteresis and hydrolytic decay in laminate tie-layers establishes real durability and regulatory compliance limits.