Synthesis and Application of a Low Dye Absorption Waterborne Polyurethane for Microfiber Synthetic Leather

As increasing attention is being paid to harmful residual dye pollution in the dyeing effluent from microfiber synthetic leather industry, there an urgent need explore innovative ways alleviate such pollution. Here, a low-polarity waterborne polyurethane (WPU) was synthesized using hydroxyl-terminated polybutadiene (HTPB) and polypropylene glycol (N220) as soft segments react with –NCO on isophorone diisocyanate (IPDI). The structure properties of modified were characterized by Fourier Transform Interferometric Radiometer (FTIR), emulsion characterization performed, including particle size zeta potential analysis, tensile test, thermal contact angle test. SEM alkali reduction rate results showed that HTPB content decreases blocking penetration corrosive ions double bond cross-link structure, but higher addition (>40%) leads enhancement phase separation, which contributes increase rate. UV spectrum analysis when amount added 50%, coloration reached 81.27% compared 13.18%, 68.09% than unmodified leather. binding dry wet rubbing color 50% grades 4–5 3–4, respectively, meets most application requirements without subsequent washing.