Materials And Their Applications Flashcards
What are the characteristics of a school shirt?
Strong, hard wearing, comfortable, easy to care for
What is a fibre?
A fine hair-like thread that can be spun with others to make a yarn
What is a synthetic fibre?
A fibre made entirely from synthetic polymers based on oil
What is meant by being Sustainable?
Ensuring that all aspects of design and manufacturing dont have a negative impact on the environment or human lives
What is a natural fibre?
A fibre that comes from natural cellulose or protein
What is a regenerated fibre?
A fibre from natural cellulose that has been chemically modified
What is a polymer?
A long chain of molecules made up of fibre forming atoms that are linked together
How are woven or knitted fabrics made?
Fibres are twisted (spun) together to make a yarn and then from there they can be used to make a woven/knitted fabric
Natural fibres:
What are plant fibres made from?
What are animal fibres made from?
Cellulose
Protein
Natural plant fibres examples:
Cotton, linen and ramie
Natural animal fibres examples:
Wool and silk
Examples of regenerated fibres:
Mostly made from natural cellulose from wood pulp or waste cotton fibres too short to be spun into a yarn so chemically treated to modify the cellulose so it can be made into fibres
Examples of regenerated (first generation manufactured fibres)
Viscose, rayon
What are some examples of second generation fibres?
Modal and lyocell
What is the most environmentally fibre?
Rayon
Viscose
Lyocell
Lyocell are more environmentally friendly fibres because they are manufactured using a closed-loop system that reuses chemicals in the process
What is polymerisation?
The joining together of small molecules to form long Chains of molecules
What is a yarn?
Long continuous strands made by twisting many individual fibres together
What are smart materials?
Materials that are able to react to external stimuli or changes in their environment without human intervention
How are man-made fibres made?
They are made from synthetic polymers that come mainly from oil. The synthetic polymers are made by joining smaller molecules together to form a long chain (process called polymerisation)
What are aramid fibres?
Technical fibres that have additional strength and durability they are stable and tear resistant. For example Kevlar is used to make stab proof and bullet proof vests
What are inorganic fibres?
Come from glass, metal, ceramics and carbon, and are used for specialist applications like micro-encapsulated and nano-fibres
What are some conditions smart materials react to?
Light, heat and power
What are reactive materials?
They react to changes such as loss of heat or presence of pollutants (many used in health and safety or sportswear applications)
What are photochromic fabrics?
They are dyed using specific types of dye that respond to changes in UV light (can be used to warn wearer of need for sun protection)
What are phase changing materials?
Able to regulate body temperature cooling down in hot conditions and warming up when it gets cooler (used for garments in extreme climates such as those worn by mountaineers)
What are microfibres?
Extremely fine synthetic fibres mainly polyester and polyamide. Very lightweight, soft, drape well, used for a variety of clothing.
What are microfibres often blended with?
Natural fibres to give high performance fabrics for outdoor and sports use. (Tactel is a polyamide microfibre, e.g. tactel aquator and Tactel Diablo)
What are nano-fibres?
Can be applied to fabric as a finish (protect from stains + make fibre more absorbent) they are very tiny size of a micron to a single polymer molecule
Micro-encapsulated fibres+fabrics
Contain health + cosmetic chemicals. When fibres are rubbed chemicals are slowly released and absorbed into skin e.g. caffeine-encapsulated tights stimulate leg veins reduces risk on deep vein thrombosis (DVT)
Info on methods for investigating and testing materials
Manufacturers carry out tests to check the potential fabrics have the performance properties required.
Recommended by the British standard Institute BSI
These state performance codes (bold) for a product material or process.
for example:
waterproof clothing - keep the wearer dry
Fabric for hotel sheets - stand up to repeated laundering
Designers give fabric specifications
Method of testing must be reliable and consistent
