TECH108 Lecture Notes - Lecture 4: Spider Silk, Fabric Structure, Coir
WEEK 4:
Properties and Performance of Textiles:
Fibre:
A fibre is a fine, thread like substance with a length at least 100 times greater than the
width. Fibres are the raw materials used to make yarns and fabrics. They contribute to the
aesthetics, durability, comfort and care of fabrics.
Short fibres are known as staple fibres. They range from 15mm to 1500 mm in length. Long
or continuous fibres are known as filament fibres.
Fibres are the basic unit of most fabrics
Many manufactured fibres were developed in the 20th century
Advances have been made in the manufactured fibre-industry such as modifications of the
original or parent fibres, to provide fibers with better properties for specific end uses.
Fibers contribute significantly to fabric performance
Some attributes of fibres are desirable and some are not, often depending on the end use
and product
While fibers plays a major role in the characteristcs of a product, other components also
greatly contribute to performance
Fibers are the building blocks used to create yarns and fabrics
Manufactured fibres:
Regenerated: Rayon, Acetate
Synthetic: Polyester, Nylon, Acrylic, Elastomeric
Natural Fibres:
Animal: Sheep, Alpaca, Camel, Goat, Rabbit, Silk, Spider silk
Inorganic: Metallic, Fibre Optics, Asbestos, Fibreglass
Vegetable: Linen, Hemp, Rubber, Coir, Sisal, Cotton
Fibre Properties:
Aesthetics:
Lustre – gloss, sparkle or shine of a fabric caused by light reflecting from the surface
Drape – How a fabric hangs or falls
A textile product should be appropriate in appearance for its end use.
Aesthetic properties relate to the way senses, such as touch and sight, contribute to
the perception of the textile.
Durability:
Abrasion resistance: Ability to absorb moisture
Strength – ability to resist breaking
A durable textile product should last a period of time adequate for its end use.
Durability properties can be tested in the laboratory, but laboratory results do not
always accurately predict performance when used by consumers.
Comfort:
Elasticity – ability to return to original shape after being stretched or compressed
find more resources at oneclass.com
find more resources at oneclass.com
Absorbancy: Ability to absorb moisture
Thermal properties: ability to withstand and transfer heat
Dimensional stability: inability to shrink or stretch
A textile product should be comfortable when it is worn or used.
This is primarily a matter of personal preference and individual perception of
comfort under different environmental conditions and degrees of physical activity.
Care:
Effect of chemicals – withstand acids, alkalis and solvents
Sun resistance – ability to withstand deterioration when exposed to sunlight
Colour fastness – ability to withstand colour change after exposure to heat or water
Shrink resistance: inability to contract
Fibre and external structure:
Fibre properties are determined by the external structure, chemical composition and
internal structure of the fibre
External structure = morphology:
Length: short = staple, long = filament. Filaments are long fibre strands of indefinite length,
measured in miles or kms. They can be monofilament ot multifilament.
Diameter, size or denier. Fibre diameter greatly influences a fabrics performance and hand
or how it feels.
Cross sectional shape: this impacts luster, bulk, body, texture and hand. Natural fibers
derive their shape from the way the cellulose is built during plant growth (cotton), the
shape of the hair follicle and the formation of protein substances in animals ( wool), or the
shape of the orifice through which the insect extrudes the fiber ( silk).
Surface characteristic – crimp: may be found in textile materials as fiber crimp or fabric
crimp. Fiber crimp refers to the waves, bends, twists, coils or curls, along the length of the
fiber. Fiber crimp increases cohesiveness, resiliency, resistance to abrasion, stretch etc.
Fabric Crimp: the bends caused by distortion of yarns. Surface contour may be smooth,
serrated, striated, or rough, and it affects luster, hand, texture and apparent soiling of the
fabric.
Chemical composition:
What fibres are made of. Cotton is made of cellulose and wool is made from protein. All
matter is made of chemicals.
Fibers are classified into groups by two criteria: Source (natural or manufactured) Chemical
composition
Cellulosic, protein, mineral, or synthetic Fibers in a generic group have similar chemical
compositions that differ from those in another group. The chemical composition determines
fiber properties, and thus end use.
Internal structure:
find more resources at oneclass.com
find more resources at oneclass.com
A monomer is the basic units of a fibre.
Polymerisation Is the process of joining monomers to form a chain or polymer.
All fibres contain crystalline and amorphous regions, which are related to ther arrangement
of the polymers. The amount of crystalline and amorphous regions varies between fibres
and determines some of the fibre properties including durability, comfort, appearance and
care.
Amorphous Structure:
Amorphous regions occur when the polymers are in random arrangement and there are
large distances between them, resulting in few binding forces and a weak fibre. Fibres with
a high perentage of amorphous regions include wool and rayon. The properties of these
fibres are generally:
- poor strength
- low durability
- good absorbancy
- can be easily dyed
- more elasticity
- good abrasion resistance
Crystalline Structure:
Crystalline regions occur when the polymers are packed closely together and in a parallel
arrangement, allowing many binding forces and resulting in a stronger fibre. A fibre with
higher percentages of crystalline regions Is nylon. Its properties are:
- strength
- high durability
- low absorbancy
- not easily dyed
- low elasticity
- poor abrasion resistance
Fibre Structure:
Except for silk, the natural fibres have 3 distinct parts:
1. an outer covering: cuticle or skin
2. an inner area
3. a central core that may be hollow.
The manufactured fibers are less complex in structure. They usually consist of a skin
and a core.
Serviceability:
Textile serviceability includes the concepts of aesthetics, durability, comfort, safety,
appearance retention, care, environmental concerns, sustainability and cost.
Appearance Retention Properties:
Resiliency
Compressibility
Compression resiliency
Dimensional stability
Shrinkage
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
A fibre is a fine, thread like substance with a length at least 100 times greater than the width. Fibres are the raw materials used to make yarns and fabrics. They contribute to the aesthetics, durability, comfort and care of fabrics. They range from 15mm to 1500 mm in length. Long or continuous fibres are known as filament fibres. Fibres are the basic unit of most fabrics. Many manufactured fibres were developed in the 20th century. Advances have been made in the manufactured fibre-industry such as modifications of the original or parent fibres, to provide fibers with better properties for specific end uses. Some attributes of fibres are desirable and some are not, often depending on the end use and product. While fibers plays a major role in the characteristcs of a product, other components also greatly contribute to performance. Fibers are the building blocks used to create yarns and fabrics. Animal: sheep, alpaca, camel, goat, rabbit, silk, spider silk.
