Thermoplastics, thermoset polymers, elastomers and biodegradable polymers

LDPE (thermoplastic)

-Tough, good chemical resistance, weatherproof, available in translucent, low level of rigidity. Safe working temperature 65 °C.

-Used for Squeezy detergent bottles, toys, carrier bags, bin liners, general packaging, food wrap film, food trays

HDPE (thermoplastic)

-Available in translucent form, weatherproof, tough, good chemical resistance.

Safe working temperature 65 °C.

-Used for Chemical drums, jerry cans, toys, household and kitchenware, long life carrier bags, buckets, bowls

Polypropylene (PP) (thermoplastic)

-Available in translucent, good chemical resistance, tough, good fatigue resistance (hinge property). Safe working temperature 100 °C.

-Used for Rope, folders, folio cases, food containers, medical equipment, hinged containers lids

HIPS (Thermoplastic)

-Hard, rigid, available in translucent, tough.

Safe working temperature 70 °C.

-Used for Yoghurt pots, refrigerator linings, single use drink cups, toilet seats, instrument control knobs

ABS (thermoplastic)

-Extremely tough, hard, available in opaque.

Safe working temperature 80 °C.

-Used for Telephone handsets, rigid luggage, domestic appliances (food mixers), handles, computer housings, remote control casings, calculator casings

PMMA (Thermoplastic)

-Tough, hard, good chemical resistance, available in translucent. Safe working temperature 95 °C.

-Used for Car light casings, computer numerically controlled (CNC) laser cut items, lighting units, lighting covers, baths

Nylon (Thermoplastic)

-Tough, corrosion resistant, good temperature

resistance, low coefficient of friction.

Safe working temperature 150 °C.

-Used for Bearings, gears, curtain rails, textiles,

boil-in-the-bag food packaging, car engine

manifolds, cable ties

uPVC (Thermoplastic)

-Rigid, opaque, tough, hard, good weathering

resistance, good chemical resistance, fire retardant. Safe working temperature 95 °C.

-Used for Window frames, external doors, guttering and downpipes for buildings, water service pipes, bank cards

PVC (Thermoplastic)

-Available in translucent, tough, flexible, good

weathering resistance, good chemical resistance. Safe working temperature 95 °C.

-Used for Hose pipes, cable insulation, medical grade tubing, inflatable products, imitation leather, seat coverings

UF (thermoset)

-Hard, heat resistant, good electrical insulator, brittle. Safe working temperature 80 °C.

-Used for Electrical fittings, adhesives

MF (thermoset)

-Hard, opaque, tough, heat resistant food safe, chemical resistant. Safe working temperature 130 °C.

-Used for Decorative laminates, picnic

ware, buttons

Polyester resin (thermoset)

-Rigid, heat resistant, chemical resistant, brittle. Safe working temperature 95 °C.

-Used for Decorative laminates, picnic

ware, buttons

Epoxy Resin (thermoset)

-Rigid, clear, hard, tough ,chemical resistant.

Safe working temperature 80-200 °C.

- Used for Adhesives, surface coatings,

encapsulation of electrical components, cardiac pacemakers, aerospace applications, used in lay-up techniques with Carbon Fibre

Reinforced Plastic

What are the main properties of elastomers

-They can be stretched many times their original length, and after the removal of tension return to their original shape

-They are self finishing

What are elastomers used for

-Overmouldings for improved grip and textures in things such as toothbrushes

Natural rubber characteristics

High tensile strength, low elongation, good hardness compared to other elastomers,

tough, electrical insulator, good cold resistance.

Natural rubber uses

Automotive industry such as tyres, tubes, hoses, gaskets, belts, balloons, toys, footwear

Butadiene Rubber (BR) characteristics

Tough, excellent wear resistance against friction, good thermal resistance against friction, electrical insulator.

Butadiene Rubber (BR) uses

Vehicle tyres, shoe soles, toys, conveyor belts, water and pneumatic hoses

Neoprene characteristics

Good thermal resistance, toughness, good oil and chemical resistance, excellent weather resistance, good abrasion resistance and electrical insulator.

Neoprene uses

Wetsuits, laptop cases, industrial wire insulation, automotive applications such as shock absorber seals, hose covers, transmission belts, gaskets and door seals

Silicone characteristics

Good flexibility at low temperatures, poor abrasion resistance, good thermal resistance and resistance to temperature extremes, good

weather resistance, good lubricating qualities, electrical insulator.

Silicone uses

Flexible ice cube trays, bakeware, cooking utensils, seals for refrigerators, machinery lubricant, sealants, mould making, medical

uses such as lubricants for prosthetics, tubing for drug delivery systems

What are biopolymers usually made out of

-Wood

-Vegetable oils

-Sugar

-Starch

What are the 2 types of biopolymers

natural and synthetic

What are natural bio-polymers

made from natural materials such as cellulose, starch and polysaccharides

What are synthetic bio-polymers

They are made from renewable resources but chemically engineered (synthesised) to break down more quickly.

When does polymer degradation happen

When the polymer undergoes a significant change in properties due to the influence of chemicals, heat or light

biodegradable polymers description

-The polymer is made from finite resources e.g. crude oil, and the polymer contains additives that cause it to degrade quicker, for example, less than 5 years

When does degradation occur

-Light (photodegradable)

-Oxygen (Oxy-degradable)

-Water (Hydro-degradable)

Why does degradation occur

-Because of the action of micro-organisms which convert the material into water, carbon dioxide (CO2), biomass and possibly methane (CH4)

-Some polymers degrade in a few weeks while

others may take several months

-The ability of a polymer to biodegrade is dependent on the structure of the polymer rather than the origin of the raw material.

Oxy-degradable polymer