Fibre Properties Part 2 - Week 3 PDF

Influence thermal property consumer to select and affect color processing mass recovery Secondary resiliency fibre properties...

Influence thermal property consumer to select and affect color processing mass recovery Secondary resiliency fibre properties elongation abrasion resistance luster moisture absorption  Luster The way a fiber reflects light from its surface Depends on: Smoothness vs irregularity of surface Smooth surfaces reflect more light Chemical orientation (amorphous vs crystalline regions) Crystalline regions reflect more light Amorphous regions reflect less ligh Types: Bright/shiny (silk, nylon) Dull/matte (cotton, wool) Affects appearance and feel Duller luster with more amorphous region Color: Varies by fibre type (wool, cotton, bast, manmade) Affects appearance  Moisture Absorption Condition Important for Ensures measurements ed Textiles are consistent Atmosphe conditioned in a like moisture results across content and re: standard tests and atmosphere moisture laboratories regain before testing: 65±2 70±2°F percent (20±2°C) relative humidity Term Definition Term Attraction and retention of Absorption Absorption moisture within the pores of a fiber Attraction and retention of Adsorption Adsorption moisture on the surface of a fiber Ability of a fiber to move moisture Wicking quickly along Wicking  Elongation and Recovery F elongation The amount of stretch or extension F that a fibre, yarn, or fabric will accept. percent elongation The ratio of the extension of a material to the length of the material prior to stretching. original length extended length (extended length  original length ) % elongation  100 original length Resilienc y  Thermal properties of fibres are Thermal those properties exhibited by a fiber when exposed to heat directly or if Thermal properties of fibres include: Effects of heat Properties Flammability exposed to similar conditions Protein fibers: Burn rapidly, melt, drip, charred flesh odor Plant fibers: Burn slowly, ash left, burnt wood odor Melting point Glass transition Safe ironing temp: Synthetic fibers: Melt, Maximum temp fiber (Tm): Point where fiber loses temp (Tg): Point where can withstand burn slowly, molten drops, shape and amorphous without damage acrid chemical odor becomes molten regions develop flow, fiber becomes pliable  Electrical Conductivity: Ability of a fiber to conduct electricity Important for static control Conductivity increases with higher moisture absorption Natural fibres are generally good condcutors (hydrophilic) Synthetics are generally poor conductors (hydrophobic) Metal/carbon fibers are good conductors  Abrasion resistance Ability of a fiber/yarn/fabric to withstand surface wear, rubbing, chafing during use Affected by: Yarn and fabric construction Fiber properties Finishing techniques Two main methods of testing: Flex abrasion (shoelaces, ropes) Flat/plane abrasion (upholstery, carpets