Chapter 3- part 2 Flashcards
What are thermoforming plastics?
- Generally more flexible
- Can be reformed many times when heated
What are thermosetting plastics?
- They have cross-links
- They are more rigid
- Once they have have been set they cannot be reformed
PETE
- Thermoforming plastic
- easily coloured+ smooth finish
- Used for bottles
HDPE
- Thermoforming plastic
- Opaque + takes colour well
- Lightweight
- Used for bins + pipes
PVC
- Thermoforming plastic
- High gloss finish
- Flexible
- Used for raincoats
LDPE
- Thermoforming plastic
- Thin to medium thick
- High strength to weight ratio
- Used for plastic bags
PP
- Thermoforming plastic
- Tough + chemically resistant
- used for stationary
PS
- Thermoforming plastic
- Food safe
- Used for yogurt pots
Acrylic
- Thermoforming plastic
- Huge colour range
- Tough but brittle when thin
- Used for car lights + trophies
Epoxy resin
- Thermosetting plastic
- 2 liquids : a resin + a hardener
- Strong + expensive
- Used for bonding different materials together
Melamine Formaldehyde
MF
- Thermosetting plastic
- Moulded into variety of shapes
- Hygienic + Lightweight
- Kitchenware
Urea Formaldehyde
UF
- Thermosetting plastic
- Mainly white colour
- Heat resistant + electrical insulator
- Used for electrical fitting
Polyester resin
PR
- Thermosetting plastic
- Similar to epoxy resin ( hardener + resin)
- Heat resistant
- Used for encapsulation of artefacts
Phenol formaldehyde
PF
- Thermosetting plastic
- Electrical insulator
- Used for electrical components
How is yarn created?
By spinning plant fibres together
Cotton
- White,fluffy
- Taken from cotton plant
- Soft + Strong
- Used mostly for clothing
Wool
- From sheep
- Warm + naturally crease resistant
- Jumpers + Coats
Silk
- From the cocoon of a silk worm
- Has a natural shine (triangle structure)
- Very soft + gentle to skin
- Luxury clothing
Polyester
- Can be made into different fabrics
- Tough, strong, hard
- Clothing , fleece garments
What is a sustainable source are polymers derived from?
Vegetable starches
Polyamide
Nylon
- Very versatile fibre
- Good strength
- Clothing + ropes
Elastane
LYCRA
- Smooth to touch
- Added stretch
- Freedom of movement
- Sportwear
Poly-cotton
- Made from polyester + Cotton
- Mote durable than cotton
- Used for bedding
How is cloth woven?
2 strands woven at 90 degrees to each other
What are warp threads?
They are a fixed loom that run the length of the fabric
What are weft threads?
They run across the width of the fabric from selvedge to selvedge
What is a plain weave?
- Weft yearn goes under and over the warp yarn
- Interlaces at 90 degrees to each other
- Cheaper to produce
- Cheesecloth
What is felting?
Matting together fibres using a combination of heat, pressure, moisture and movement
Bonded fabric
- Lack strength
- Can be cut in any direction
- Used ad disposable products
Felted fabrics
- Wide range of fibres
- Has no elasticity
- Used for hats + insulation
What is weft knitting?
- Interlocking loops across the width of a fabric
- Quite stretchy
What is warp knitting?
- Loops interlocked vertically
- Tend to hold their shape
Knitted fabric
- Loops of yarn interlocked
- Warm to wear
- Jumpers + cardigans etc
