Analysing the Effects of Thread Pitch and Angle on the Combustion Characteristics of Cotton/Nylon Fabrics: Implications for Fire Behaviour and Safety

Abstract

This study examines the effects of thread pitch and thread angle on the combustion characteristics of cotton/nylon blended fabrics, focusing on flame spread rate, heat release behaviour, and fire performance. Fabric samples were produced using a plain weave structure with cotton as warp fibres and nylon as weft fibres, with thread angles ranging from 0° to 90° and thread pitch from 0 mm to 5 mm. Flame spread experiments were conducted under controlled conditions, and combustion behaviour was analysed by observing and measuring flame propagation. The results show that increasing the thread angle reduces flame spread rate due to fibre misalignment, reduced heat transfer, and the melting behaviour of nylon fibres. In contrast, a larger thread pitch enhances flame spread by improving airflow and oxygen availability within the fabric structure. Cotton fibres exhibited charring and sustained combustion, while nylon fibres melted and evaporated, influencing overall flame behaviour. The combined effects of thread angle and pitch demonstrate that fabric geometry plays a significant role in combustion performance. These findings provide valuable insights for designing textile materials with improved fire safety and energy efficiency.