Structure–Property Investigation of Knit Patterns on Thermal Comfort: A Holistic Approach

While recent advances in material science enabled multifunctional textiles, little is known about how the textile structure alone changes the response. This research aims to enhance the heat resistance of the inner fabric layer of winter wear clothing, specifically for military personnel by inducing air gaps in the fabric structure, and investigate the structure–property relationships in terms of thermal and moisture wicking. Here, 12 knitted textiles are produced with the same polyester yarn using a Stoll flatbed knitting machine. Among the 12 knitted textiles, six are standard knit patterns and other six are non-standard (NS) complex knit patterns. Thermal resistance is measured using the guarded sweating hotplate method, while moisture transfer involved vertical and horizontal moisture wicking methods. One-way ANOVA of the results exposits that changing knit structures can significantly manipulate both thermal and moisture characteristics; a knitted fabric with two different sides can provide different insulations when the technical face and back are reversed during use because of asymmetric entrapped pockets of air. NS knits exhibit superior insulation properties (up to 333% more compared to a Single Jersey fabric) than simple designs due to the inherent self-folding nature. On the other hand, wicking properties of standard knits are better than those of NS structures due to having more capillary spaces with lower thickness. The liquid wicks faster along the wale (lengthwise) direction for most of the case rates, which can also be tuned by introducing self-folding behavior. Both thermal and moisture transfer properties are driven by the design features of the fabrics such as symmetricity and self-folding as well as structural parameters such as fabric thickness, weight, and porosity, as revealed by a simple linear regression model. This research explores the tunability of comfort properties by changing the fabric structure to drive the functional design of future apparel.