Plastic

Can you think of advantages or disadvantages of using plastics in our daily lives?

Can you name different products made out of plastic ?

Plastics Task – name 10 objects made of plastic that is in close proximity to you.

Plastic

• how do we use plastics in our homes?

Photographs below courtesy of www.bodieandfou.com www.thelollipopshoppe.co.uk

Can you think of ways we use plastics in:

Plastic

• packaging

Can you think of ways we use plastics in:

• entertainment

• Thermoplastics

Plastic

This material is man made and is a by product of the oil industry.

There are two types of plastic :

• Thermosetting

These are described as plastics that can be reformed using heat : this plastic has a memory, it returns to its original flat shape when re-heated.

Here are some examples and their uses :

Acrylic – available in almost any colour in sheet rod or tube form, can be shaped using a line bender or vacuum former.

ABS – a very commonly used plastic can be injection moulded from a powder form.

Thermoplastics materials

Styrene – very good for vacuum forming.

thermoplastic resin.

Polypropylene

ABS.

Polyester resin – poured into moulds to make products or for boat repair

Thermosetting materials

These are described as plastics that do not reform using heat, they “SET” and cannot be reshaped .

Urea formaldehyde – electric plugs and sockets

Melamine – kitchen worktops, unbreakable drink mugs

Here are some examples and their uses :

Harry Allen’s paper weight/doorstop

made from resin

Kettle saucepan handles

Materials – PlasticsPlastics are synthetic resinous substances that can be moulded with the help of heat or pressure. There are two main classes of plastics:

• Thermosetting – plastics that can only be heated and be moulded once. If re-heated they cannot soften.

• Thermoplastics – plastics that are moulded by heating and can be remoulded if heated again. Thermoplastics soften when heated and can be shaped when hot. The plastic will harden as it cools down.

Thermoplastic Thermoplastic properties

Thermoplastic uses Example outcomes

Acrylics or Perspex (Polymethyl

Methacrylate)

Stiff, hard, shiny, brittle in small sections, durable,

scratches easily, available in different colours, good

electrical insulator

Used for signs, key rings, lighting, storage containers

High impact polystyrene (HIPS)

Light but strong plastic, available in sheets in a

variety of thicknesses and colours and softens at

about 95 degrees

Used for vacuum forming and making outer casings and packaging for products

Acetate Hard, shiny and translucent/transparent

Used in badge-making, packaging and for overhead

projector transparencies

Expanded polystyrene (styrofoam)

White, lightweight and crumbly

Used for protective or insulating packaging

Materials - Plastics

Materials – PlasticsThermoplastic Thermoplastic properties

Thermoplastic uses Example outcomes

Polypropylene (PP) Light, hard, flexible but can scratch easily.

Durable to wear and has good resistance to

chemicals

Used for different kinds of packaging, chairs,

gadgets, textiles and automotive components

Low density polyethylene (LDPE)

Soft, flexible, good resistance to chemicals, good electrical insulator,

tough

Used for packaging film, carrier bags, bottles, toys

High density polyethylene (HDPE)

Hard, stiff and strong. Able to be sterilised

Used for plastic bottles, tubing and household

equipment

Corrugated plastic Lightweight, rigid and weatherproof

Used for sign boards and folders

Low-tack masking film Flexible and transparent Used to position sticky-backed vinyl letters or images onto a chosen

surface. Used for creating signs, stencils and vehicle

signage

Polyvinyl chloride (PVC) Stiff, hard wearing, brittle but can be treated to

make it softer and more rubbery

Used for blister packs, window frames, records

and clothing

Materials - Plastics

It’s just another plastic bag!

Are there any problems or issues with using carrier bags ?

Task 1 – in smalls group, list three advantages and disadvantages of using carrier bags.

Task 2 – in your group consider two ways of improving any problems that you have identified.

How many supermarket carrier bag does the average shopper use to carry goods home every week?

Supermarkets hand out 1.75 billion bags a year.

5 1215 20

How could this number be reduced? By using shopper bags, how many carrier bags could we cut down on using in a year?

20 plastic bags a week x 52 weeks = 1,040Shopper bags

2 million mobile phones are expected to go on the scrapheap during a Christmas period.

11 million people expect to get a new mobile phone over Christmas in the UK.

What can be done to improve this?

What happened to your old mobile phone?

Just one more phone …it won’t matter.

Plastic and sustainability aspects.

Before we use plastic materials aspects for consideration

Plastic is a precious resource made

from oil. Because it is such a versatile

material, we use it a lot.

2. List 5 plastic products that no-one

should ever bothered making.

Working in small groups – discuss the following and feed back to the class.

3. List 5 plastic products that would be

better made from a different materials.

1. List 5 products where plastic is the

best material to use.

Photographs courtesy of photo gallery wales.