Polymers

• Thermoplastics are made up of long chains of molecules that are tangled together and have no fixed pattern, becoming soft when heated and stiff when cooled, with a "memory" to return to their original shape when reheated
• Thermosetting plastics are made up of long chains of molecules that are cross-linked, softening when heated but setting due to their rigid molecular structure, unable to be reheated and reshaped like thermoplastics
• Acrylic properties include good impact strength, lightweight, good electrical insulation, and durability, used in ornamental fish tanks, baths, car indicator covers, with advantages like recyclability and environmental stability but disadvantages of being relatively soft and easily scratched
• Polyethene is tough, resistant to chemicals, soft, and flexible, used in drawer bottoms, cabinet backs, and lightweight internal door cladding, with the disadvantage of not being very strong due to lacking grain but the advantage of being the cheapest of manufactured boards. Aesthetically it's side is very smooth and underside textured.
• Polyvinyl chloride (PVC) properties include good chemical and weather resistance, lightweight, good electrical insulation, stiffness, toughness, waterproofness, and durability, used in pipes, bottles, window frames, and electrical insulation tape, with the disadvantage of producing dangerous fumes when burnt. Also with the advantage of it being relatively cheap to manufacture and it can be recycled
• High impact polystyrene (HIPS) is tough, rigid, a good electrical insulator, used in food appliances, toys, and DVD cases, available in various colors, machinable, and recyclable, but expensive and limited in flexibility
• Acrylonitrile-butadiene-styrene (ABS) properties include high impact strength, toughness, scratch resistance, lightweight, durability, and good chemical resistance, used in kitchenware, toys, and car components, available in various colors but relatively expensive compared to polystyrene
• Polyester resin is a good electrical insulator, hard, brittle, with good heat and chemical resistance, used in casting, boat hulls, model figures, and adhesives, with advantages like color mixing and water resistance, but contracts on curing and can cause excess heat with too much catalyst
• Urea formaldehyde properties include stiffness, hardness, brittleness, scratch resistance, stain resistance, and high tensile strength, used in tableware, buttons, and electrical casings, with advantages like colorability and high surface hardness, but toxic fumes are emitted when curing