Plastics Flashcards
Thermoplastics
Thermoplastics are linear chain molecules with weak secondary bonds between the chains.
Types of thermoplastics
Polypropylene (PP)
Polyethylene (PE)
Polyethylene (PET)
ABS
HIPS (Polystyrene)
PVC
Properties of PP
lowest density of thermoplastics
good toughness
resistant to fats
high resistance to temperature
good fatigue resistance
semi-rigid
translucent
recyclable
What is PP used for?
Buckets, bowls, crates, toys, food containers, juice bottles, straws, coat hangers, furniture eg plastic chairs),
Properties of PE
low stiffness (semi-rigid, flexible)
high toughness
translucent
commonly HDPE and LDPE
recyclable
What is PE used for?
Water bottles, food storage containers, plastic tubing, light work surfaces, shampoo bottles, flower pots
What are the properties of PET
high tensile strength
rigid
thermal resistant
recyclable
What is PET used for?
Soda and water bottles, clam-shelll food containers, fibers (eg polyester), parts made by injection moulding,
What are the properties for ABS
high impact resistance
high toughness
dimensional stability
good stiffness
good workability properties
versatile material
repayable – not all centres will receive it.
What is ABS used for?
telephone handsets, rigid luggage, domestic appliances, handles, some helmets (impact), product prototyping,
What are the properties of HIPS
easy of fabrication
high impact strength
good aesthetics-various colours
rigid/stiff
low cost
dimensional stability
good workability properties
non-biodegradable
What is HIPS used for?
toys, kitchen utensil, shelves, signs, product casings.
What are the properties of PVC
Can be stiff or flexible (when a plastizeer is added)
good aesthetics – colours
low cast
non-biodegradable
What is PVC used for
potable piping, water bottles, cling film, credit cards, toys, shampoo bottles, imitation leather, window frames, rain gutters, garden furniture, binders and even pens – as a wide use
What are thermosetting plastics?
Thermosets are linear chain molecules with strong secondary bonds between adjacent polymer chains.
What are the different types of thermosets
Polyurethane
Urea formaldehyde
Melamine resin
Epoxy resin
What are the properties of polyurethane
It can be hard like fibreglass or soft and spongy
wide range of hardness
good tensile and compressive strength
toughness – impact resistant
good electrical resistivity
good bonding properties
good resistant to damp environments
What is polyurethane used for?
wheels, wing parts, sponges, finishes (lacquer etc), toys,
What are the properties of urea-formaldehyde?
high (surface) hardness
high tensile strength
good
electrical resistivity
low resistance to damp environments
deterioration of indoor are quality
What is urea-formaldehyde used for
manufacture of man-made timber (pressed) products such as MDF particle board, adhesives, insulation, wrinkle and shrink resistant textiles
What are the properties of melamine resin
high hardness (one of the highest)
high chemical resistance resin
medium fire and heat resistant (will decompose under great heat)
resistant to moisture (damp environments)
What is melamine resin used for
kitchen ware (plates, utensils), decorative laminates (counter or table tops), fire retardant clothing,
What are the properties of epoxy resin
high thermal resistance
high chemical resistance (less likely to corrode)
high toughness
What aims epoxy resin used for
adhesives, fibre optics, electrical insulators and transformers, craft and jewelry industry
