1.2 Performance characteristics of materials - Polymers Flashcards
Define thermosetting polymer (2)
- A material which when heated undergoes a chemical change whereby the molecules from rigid cross links
- They cannot be reheated and reshaped, even at very high temperatures
Names of thermosetting polymers (4)
- Urea Formaldehyde (UF)
- Melamine formaldehyde (MF)
- Polyester resin
- Epoxy resin
Properties of Urea formaldehyde (5)
- Hard
- Heat resistant
- Good electrical insulator
- Brittle
- Safe working temp 80°c
Uses of urea formaldehyde (2)
- Electrical fittings
- Adhesives
Properties of melamine formaldehyde (MF) (6)
- Hard
- Opaque
- Tough
- Heat resistant food safe
- Chemical resistant
- Safe working temp 130°c
Uses of melamine formaldehyde (MF) (3)
- Decorative laminates
- Picnic ware
- Buttons
Properties of polyester resin (5)
- Rigid • Heat resistant
- Chemical resistant
- Brittle
- Safe working temp 95°c
Uses of polyester resin (3)
- Castings
- Used in layup process for glass reinforced plastic (GRP) for boat hulls
- car parts e,g chair seats
Properties of epoxy resin (6)
- Rigid
- Clear
- Hard
- Tough
- Chemical resistant
- Safe working temp 80°c-200°c
Uses of epoxy resin (6)
- Adhesives
- Surface coatings
- Encapsulation of electrical components
- Cardiac pacemakers
- Aerospace applications
- Used in lay-up techniques with Carbon fibre reinforced plastic
Define a thermoforming/thermo plastic
A material that can be repeatedly reheated and shaped
Names of thermoplastics (9)
- Low density polyethylene (LDPE)
- High density polyethylene (HDPE)
- Polypropylene (PP)
- High impact polystyrene (HIPS)
- Acrylonitrile butadiene (ABS)
- Polymethylmethacrylate (PMMA)
- Nylon
- Rigid polyvinyl chloride (uPVC)
- Flexible polyvinyl chloride (PVC)
Properties of low density polyethylene (LDPE) (6)
- Very tough
- Good chemical resistance
- Weatherproof
- Available in translucent
- Low level of rigidity
- Safe working temp 65°c
Uses of low density polyethylene (LDPE) (5)
- Squeezy detergent bottles
- Toys
- Carrier bags
- Bin liners
- General packaging - food wrap film, food trays
Properties of high density polyethylene (HDPE) (5)
- Available in translucent form
- Weatherproof
- Tough
- Good chemical resistance
- Safe working temp 65°c
Uses of high density polyethylene (HDPE) (7)
- Chemical drums
- Jerry cans
- Toys
- Household and kitchen ware
- Long life Carrier bags
- Buckets
- Bowls
Properties of polypropylene (PP) (3)
- Available in translucent form
- Good chemical resistance
- Safe working temp 65°C
Uses of polypropylene (PP) (6)
- Rope
- Folders
- Folio cases
- food containers
- Medical equipment
- Hinged container lids
Properties of high impact polystyrene (HIPS) (5)
- Hard
- Rigid
- Available in translucent form
- Tough
- Safe working temp 70°c
Uses of high impact polystyrene (HIPS) (4)
- Yoghurt pots
- Refrigeration linings
- Single use drink cups
- Instrument control knobs
Properties of Acrylonitrile butadiene styrene (ABS) (4)
- Extremely Tough
- Hard
- Available in opaque
- Safe working temperature 80°c
Uses of Acrylonitrile butadiene styrene (ABS) (7)
- Telephone handsets
- Rigid luggage
- Domestic appliances
- Handles
- Computers
- Remote control casings
- Calculator casings
Properties of polymethylmethacrylate (PMMA) (5)
- Tough
- Hard
- Good chemical resistance
- Available in translucent
- Safe working temp 95°c
Uses of polymethylmethacrylate (PMMA) (5)
- Car light casings
- CNC laser cut items
- Lighting units
- Lighting covers
- Baths
Properties of nylon (5)
- Tough
- Corrosion resistant
- Good temperature resistance
- Low co-efficient of friction
- Safe working temp 150°C
Uses of Nylon (7)
- Bearings
- Gears
- Curtain rails
- Textiles
- Boil-in-the-bag food packaging
- Car engine manifolds
- Cable ties
Properties of Rigid polyvinyl chloride (uPVC) (7)
- Rigid
- Opaque
- Tough
- Hard
- Good weathering resistance
- Fire retardant
- Safe working temp 95°C
Uses of Rigid polyvinyl chloride (uPVC) (5)
• Window frames • External doors • Guttering and downpipes for buildings • Water service pipes • Bank cards
Properties of flexible polyvinyl chloride (PVC) (6)
- Available in translucent
- Tough
- Flexible
- Good weathering resistance
- Good chemical resistance
- Safe working temp 95°C
Uses of Flexible polyvinyl chloride (PVC)(5)
- Hose pipes
- Cable insulation
- Medical grade tubing
- Inflatable products
- Imitation leather seat coverings
Plastics recycling
Characteristics of polymers
- Made mostly from a non-renewable energy resource in crude oil
- Synthetic polymers are made from crude oil and take hundreds of years to degrade
- Polymers are self finished as it can be pigmented during the manufacture process to give colour therefore require no secondary finishing process
Stock forms (6)
- Granules - a small particle of plastic
- Sheet - large flat sections of polymer in varying thicknesses
- Film - very thin sheet polymer
- Rods and other extruded forms, tubes and bars
- Foam - solid form made by including air or other gases e.g styrofoam from expanded polystyrene
- Powder - a very fine granule of polymer
