CH 4 - Fiber Classification & Properties Flashcards
What factors determine whether a fiber will have a broad, modern-market appeal?
It must be plentiful, competitively priced, and able to be processed successfully and efficiently.
What fibers are considered natural fibers?
Cellulose (plant) fibers such as cotton, flax, hemp, jute, and sisal.
Protein (animal) fibers such as silk, wool, fleece such as mohair and cashmere from goats, angora from rabbits.
Mineral fibers such as glass and asbestos.
What are four subgroups of manufactured fibers?
Regenerated fibers
Synthetic fibers
Biopolymer fibers
Mineral fibers
Natural and manufactured fibers are identified by a ________ name (for natural fibers) or a _____________ name (for manufactured fibers)
Common and generic
How do these fabrics react to a burn test: (a) cellulosic fibers; (b) protein fibers; (c) synthetic fibers; (d) blends?
(a) cellulosic fibers burn quickly, smell like burning paper and have an ash residue;
(b) protein fibers burn slowly and are often self-extinguishing. They smell like burning hair and have a harder residue than plant fibers;
(c) . Synthetic fibers melt, smell like burning plastic, and have a hard bead residue;
(d) . Blends can have a mixture of reactions.
The various atoms present in each fiber are combined into distinctive molecular fiber-forming units known as ________.
Monomers
The process by which thousands of monomers are linked by strong chemical bonds into extremely long chain-like units.
Polymerization
Four arrangements that the polymer chains assume the?
1) . Oriented - polymer chains are aligned parallel to the long axis of the fiber;
2) . Amorphous - polymer chains that do not exhibit any orderly, crystalline structures.
3) . When weaker bonds form between adjacent chains of the laterally or longitudinally parallel.
What are some of the external features of fibers?
Cross-sectional shape Surface texture Longitudinal configuration Length Diameter
What’s the difference between staple fibers and filament fibers?
Staple fibers are short fibers measured in inches. All the natural fibers except silk are staple fibers.
Filament fibers are long, continuous fiber strands of infinite length, typically measured in yards or meters. All manufactured fibers are originally produced in filament form, but often cut into staple lengths and spun into yarn. Silk is also a filament yarn.
Which yarns (staple of filament) have greater tensile strength?
Filament, the longer the filament the greater the strength
List the aesthetic properties of fibers?
Luster
Hand
Drape
Texture
List the Appearance Retention properties of fibers.
Abrasion resistance Flexibility Tenacity Elongation Cohesiveness Light Resistance Insect Resistance Resiliency Compression Resiliency Elastic Recovery Dimensional Stability and Shrinkage Resistance Propensity to Pill Oleophilic propensity (attraction to oily stains) Soil repellency
What is meant by elongation/
The ability of a fiber to be stretched and extended without breaking
What is meant by tenacity?
Strength
What is meant by flexibility?
The ability of the fiber to bend repeatedly without breaking.
What is meant by cohesiveness?
The ability of fibers to cling together during spinning
What is light resistance?
The ability of a fiber to resist degradation due to exposure to light.
What is resiliency?
The ability of a fabric material to recover from folding, bending, crushing, or twisting, and is directly related to wrinkle recovery.
What is compression resiliency?
Loft; the ability of the fiber to spring back to its original thickness after being compressed.
What is elastic recovery?
How completely a fiber returns to its original length after being elongated.
What is dimensional stability?
The ability of a fiber to retain its original size and shape throughout use and care
What is shrinkage resistance?
The ability of a fiber to retain its original shape during cleaning.
What does oleophilic mean?
Strong attraction to oily stains