Effect of loop length and filament fineness on thermo-physiological properties of polyester-cotton plated knit structures

Thermo-physiological properties of fabrics intended for next to skin applications, apparel, and functional wear are related to the heat and moisture transmission properties. A gammet of fiber, yarn, and fabric variables affect the thermal and moisture management properties and hence contribute to the overall comfort and state of well-being of the wearer. In this study, the effect of loop length and filament fineness on the thermo-physiological properties of polyester-cotton single jersey plated fabrics has been reported. The thermo-physiological properties were correlated with structural parameters of knit structures such as fabric tightness factor, thickness, porosity, stitch density, and loop length. Fabrics knitted with longer loop length (slack constructions) showed higher thermal resistance and would be perceived warmer on initial skin contact owing to lower value of thermal absorptivity, were permeable to air and moisture vapor transmission, had higher water evaporation percentage however water absorbency and transplanar wicking was lower. Fabrics knitted with finer filaments showed higher value of thermal resistance, lower value of thermal absorptivity, and were less permeable to air and moisture vapor transmission. The water absorbency and transplanar wicking increased and water evaporation percentage decreased as the filament fineness increased. General linear model was used to obtain prediction models in the form of equations at varying levels of loop length and filament fineness. A high value of coefficient of determination between predicted and experimental values validated the model. Pearson correlation coefficient was deduced to establish pair-wise association among the different thermo-physiological properties. Air permeability was observed to be positively related to moisture vapor transmission rate and water evaporation percentage as suggested by high values of pearson correlation coefficients.