Preparation and Flame‐Retardant Mechanism of Aramid‐Viscose Coated Fabrics With TPU Matrix Modified by TPP / DBDPE / MCA Ternary Synergistic System

ABSTRACT To address the inherent flammability of thermoplastic polyurethane (TPU)‐coated fabrics, a phosphorus‐nitrogen‐bromine (P‐N‐Br) ternary synergistic flame‐retardant system was constructed using TPU as the matrix, incorporating tripheny phosphate (TPP), decabromodiphenylethane (DBDPE), and melamine cyanurate (MCA). Flame‐retardant aramid‐viscose coated fabrics were fabricated via solvent dissolution‐double dip‐double roll processing, with the flame‐retardant ratio optimized by response surface methodology (RSM) using vertical burning damage length as the key index, yielding the optimal formulation TPU‐0. Characterization results showed that TPU‐0 achieves a vertical burning damage length of 32 mm and self‐extinguishes within 1 s, forming a dense char layer with uniform P/N distribution and enhanced graphitization (I D /I G = 0.91). The ternary system exerts a dual‐protection mechanism: TPP catalyzes ordered char formation, MCA facilitates char expansion, and DBDPE scavenges gas‐phase radicals. Additionally, TPU‐0 retains superior multifunctional performance, with a tensile strength of 17.1 MPa, water contact angle of 110°, and ultraviolet protection factor (UPF) of 226.2. This work provides a technical basis for high‐performance protective textiles, especially firefighting suits.