Question 28 (Textile Engineering & Fibre Science)
With increase in relative humidity from 0 to 100%, the tensile properties of cotton fibre change such that
|(A)||Modulus and strength increase, extensibility decreases|
|(B)||Modulus decrease, strength and extensibility increase|
|(C)||Modulus and strength decrease, extensibility remains same|
|(D)||Modulus and strength decrease, extensibility increases|
Option A is correct
Frequently Asked Questions | FAQs
What are the tensile properties of cotton?
Cotton, a natural fiber derived from the cotton plant, possesses certain tensile properties that contribute to its overall strength and performance. Here are some key tensile properties of cotton:
Tensile Strength: Cotton fibers have a relatively high tensile strength, meaning they can withstand pulling forces without breaking. On average, cotton fibers have a tensile strength of around 3 to 5 grams per denier (g/d) or 27 to 45 cN/tex. However, the tensile strength can vary depending on factors such as the fiber’s maturity, fineness, and processing methods.
Elasticity: Cotton fibers have limited elasticity compared to synthetic fibers like elastane or spandex. When subjected to tension, cotton fibers elongate to a certain extent but do not have significant elastic recovery. This lack of elasticity makes cotton fibers prone to elongation and deformation under heavy loads or excessive stress.
Breaking Elongation: Cotton fibers exhibit moderate breaking elongation, which refers to the extent to which the fibers can stretch before breaking. On average, cotton fibers have a breaking elongation of around 7% to 8%. This breaking elongation allows cotton fabrics to withstand moderate stretching without immediate breakage but can lead to permanent elongation and sagging over time.
Modulus of Elasticity: The modulus of elasticity, also known as Young’s modulus, indicates the stiffness or rigidity of a material. Cotton fibers have a relatively low modulus of elasticity compared to synthetic fibers. The modulus of elasticity for cotton fibers typically ranges from 3 to 8 g/d or 27 to 72 cN/tex. This lower modulus gives cotton fabrics a softer and more comfortable feel compared to fabrics made from stiffer fibers.
It’s important to note that the tensile properties of cotton can be influenced by various factors such as the cotton variety, processing techniques, spinning methods, and fabric construction. Additionally, these properties can also be modified through various treatments or finishes applied to the cotton fibers or fabrics.