iv. polymers

Polymers

A key term used to describe different plastics

What are most polymers synthetic?

Yes

What are polymers usually made from?

Crude oil

What are the other sources of polymers?

Coal, gas

How to create different types of polymers?

Crude oil is refine and mixed with other chemicals

What are the impacts of polymers?

• they don’t biodegrade quickly

• Can pollute ocean quickly

• Harm wildlife

What are the 2 types of polymers

• Thermoforming

• Thermosetting

What are thermoforming polymers?

Can be repeatedly heated and moulded

Pro of thermoforming

It can be recycled

Con of thermoforming

Hard to complete intericate details

What are thermosetting polymers?

Are hard and durable and they cannot be reformed once set into shape

Why can’t thermosetting polymers be recycled?

Cross-linking of molecular chains in thermosetting polymers creates a rigid structure by joining the chains, this prevents them from being recycled

Pros of thermosetting

• Hard and durable

• Able to withstand high temperatures

Con of thermosetting

Cannot be recycled

Why are plastics used?

• Relatively versatile

• Relatively inexpensive

• Aesthetically pleasing

What is the other term for acrylic?

PMMA : polymethyl methacrylate

Describe acrylic

• Sheets, rods, tubes

• Wide range of translucent/ opaque colours/ sizes

Properties of acrylic

• Tough

• Easily cleaned

• Easily finished

• Easily scratched

• Inert

Uses of acrylic

• Shop signs

• Rear car lights

• Baths

Advantages of acrylic

• Does not need painting

• Widely available

• Common in schools as it’s easy to finish products

Disadvantage of acrylic

• Breaks easily if dropped

Describe high impact polystyrene (HIPS)

• Sheets, tubes, rods

• Wide range of translucent/opaque/sizes

Properties of HIPS

• Lightweight

• High stiffness

• Impact resistance

• Easily scratched

Uses of HIPS

• Toy

• Television parts

• Refrigerator linings

Advantages of HIPS

• Commonly used for vacuum forming

• Low melting point

Disadvantages of HIPS

• Low melting point

• Become brittle when exposed to UV light

Describe biopol

• Fibres, granules, sheets

Properties of biopol

• Lightweight

• Good electrical Insulator

• biogegradable

Uses of biopol

• Razor

• Cutlery

• Packaging

Advantages of biopol

• Biodegradable

• Can be injection moulded/ vacuum forming

Disadvantages of biopol

• Expensive

• Low resistance to impact

Is acrylic thermo setting or thermoforming?

Thermoforming

Is biopol thermosetting or thermoforming?

Thermoforming

Is HIPS thermosetting or thermoforming?

Thermoforming

Describe polyester resin

• Thick liquid for casting/ layup

Properties of polyester resin

• Rigid

• Brittle

• Good electrical and heat insulation

• Good chemical resistance

Uses of polyester resin

• Boat hulls

• Car bodies

• Casting for models

Advantage of polyester resin

• Can be polished to high finish

• Can be used with glass fibres to create lightweight and very strong products

Disadvantages of polyester resin

• Can be chipped if dropped

Describe urea formaldehyde

• Power, granules, preforms

Properties of urea formaldehyde

• Rigid

• Hard

• Brittle

• Heat resistance

• Excellent electrical insulation

Uses of urea formaldehyde

• Electrical fitting

• Adhesive

Advantages of urea formaldehyde

• Can be coloured using pigments

Disadvantages of urea formaldehyde

• Can break of dropped

Is urea formaldehyde thermosetting or thermoforming?

Thermosetting

Is polyester resin thermoforming or thermosetting?

Thermosetting

What is PVC (polyvinyl chloride)

a thermoplastic containing chlorine + carbon

Insulator

a material with low conductivity preventing electrical current or heat to flow

Toughness

Polymers are tough