Use the knowledge you have learnt in previous lessons Learn about Thermosetting & thermoforming plastics (Polymers) You will be tested on this topic It is important to be aware of what plastics are and how/ where they are used (2 singles and a test in the 3rd single lesson) Use the knowledge you have learnt in previous lessons

Key words Plastics, Thermo forming, Thermo setting, Polypropylene, Polymers STARTER This is a simple starter activity to get students to focus on plastic products common to them. You can replace the list of products and plastics with suitable examples from the classroom students are in.

Starter Take a few minutes to look around the room and identify some everyday plastics. Can you find the following objects and decide what type of plastic they are made from? Polypropene Chairs Jumper Comb Carrier bag Pencil case Acrylic Nylon STARTER This is a simple starter activity to get students to focus on plastic products common to them. You can replace the list of products and plastics with suitable examples from the classroom students are in. Polyethene Neoprene

Where do plastics come from? - Natural plastics, are found in animal horns (Casein glue), trees (latex, rubber) Synthetic plastics, are all modern plastics the source of these plastics is crude oil. Made by a process called Polymerisation

Types of plastics Thermoforming Plastics can be reheated and therefore reshaped. Soften when heated Can be reshaped More commonly used in school CAN be recycled Thermosetting Plastics cannot be reheated and reshaped due to a chemical reaction that occurs when they are first manufactured. Initially set by heat Cannot be reshaped once set Extremely strong and durable CANT be recycled Write key terms in box on worksheet. Thermoforming- Can be adjusted by heat sheets, granules, powder form and rods Thermosetting- cant be reheated, resin or powder form The word thermoplastic and thermoset can be explored before revealing the descriptions. For example, Thermo = heat Plastic = bend without breaking/flexible with the application of heat Set = will not move after initial heat is applied. Think of the word “set” what does it mean? (Put something is a set position)

Thermosetting and thermoforming Click here 5 mins but can miss ending off.

Uses of plastics- Thermo setting Name Uses Pictures Urea Formaldehyde (UF) sockets/ electrical fittings. Melamine formaldehyde (MF) - pan handles, electrical plugs, kitchen laminated surfaces (ER) Epoxy resin Metal coatings, used in electronics- often added to other materials to protect and reinforce. PR Polyester resin Bonded to other materials- i.e. FRP (fibre class reinforced Plastic for reinforcement. a solid or liquid synthetic organic polymer used as the basis of plastics, adhesives, varnishes, or other products.

Properties of thermosetting Waterproof Durable Hard Scratch resistant Resists high temperatures Electrical insulator

Uses of plastics- Thermoforming Name Uses Pictures Polythene plastic bags, food containers, and other packaging. High impact Polystyrene (HIPS) packaging, cd casing, toys, TV parts, plastic cutlery, Polypropylene Chairs, boxes, storage, kettle, bottles, straws PVC ( polyvinyl chloride) Construction industry (pipes) HIPS - High Impact Polystyrene, it is a tough, rigidplastic material with high impact strength which can be guillotined, punched, routered or sawn easily, and is readily available in a wide variety of colours It is glossy and is an easy to process plastic that is also sturdy and durable. It is furthermore also a rather flexible product that can be used for a diverse range of applications because it can resist high impact. The product is hygienic and visually attractive.

(forms plastic is sold in) Stock forms (forms plastic is sold in) Sheet Film Bar Rod Tube

Properties of thermo plastics/ forming Waterproof Tough Lightweight Easily coloured Durable Scratch resistant Good strength to weight ratio Corrosion resistant Chemically resistant Easy to mould Good flexibility

Properties of plastic and what they mean Hardness Is the ability of a material to resist wear, scratching and indentation Some are harder than others- but prone to scratching. Elasticity Ability for a material to bend and then return to its original position. Good elasticity- esp. thermoforming plastic. Conductivity Conductivity- ability for electricity to pass through. They have low electric conductivity –so are electrical insulators. . Toughness Is the ability of a material to withstand blows or sudden shocks without breaking Some are tougher than others. Strength Is the ability of a material to withstand a force without breaking or bending Some are, some are not- a composite material can increase this.