Effect of heat-set temperature on the crease recovery behavior of cotton fabric dip-coated with shape memory polyurethane

Abstract

The primary cause for low crease resistance in cotton fabric is the intermolecular hydrogen bonding rearrangement between the cellulose chains and inter yarn slippage. In this study, the crease recovery angle (CRA) of cotton fabric is enhanced by utilizing the shape memory effect of the shape memory polyurethane (SMPU). The SMPU was coated on cotton fabric via a simple dip coating method. The variation in CRA of SMPU coated fabric with temperature and load is monitored. The effect of heat-set temperature and thermomechanical variables - load and temperature on the shape memory performance of SMPU coated fabric is analysed. The results revealed that SMPU coated fabric heat-set at 140 °C displayed maximum shape recovery of 73.8% (at 10 N load and 50 °C programming temperature), which is retained after 10 washing treatments. In contrast, the memory performance deteriorated drastically in 100 °C SMPU/cotton (24% loss in CRA) and uncoated cotton samples (43% loss in CRA). The superior crease recovery is attributed to the molecular interaction between SMPU and cotton, which is affirmed by FTIR and Raman spectroscopic techniques. The shape memory effect of SMPU with concurrent crosslinking to cotton is responsible for the excellent crease recovery of fabric.