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CHAPTER 1 INTODUCTION TO PLASTIC
CHAPTER 1INTODUCTION TO PLASTIC
INTODUCTION TO PLASTIC
AIM:
1.KNOW IMPORTANCE OF PLASTIC2.UNDERSTAND ABOUT VARIOUS CHARACTERISTIC OF PLASTIC
INTRODUCTION TO PLASTIC• ISI KANDUNGAN:
IMPORTANCE AND HISTORY
CHARACTERISTIC
ADDITIVES
CATEGORIES OF PLASTICS
USES OF PLASTICS
COLOURANTS
STABILIZERS
FILLERS
PLASTICISERS
LUBRICANTS
SUMMARY
KUIZ
IMPORTANCE AND HISTORY
• Before the advent synthetic, most form construction used natural material such as metal, wood, rubber,, tin and etc
• Now most of this material replace with new material called plastic.
• There are many types of plastic which produce by manipulating the molecule and changing the chemical combination
IMPORTANCE AND HISTORY
• Every activity in modern life is influenced by plastics and many depend entirely on plastics products. Imagine cars without synthetic bumper, dashboards, steering wheels and switches; medicine without plastic hypodermic syringes and artificial hip joints.
IMPORTANCE AND HISTORY
• And what about telecommunications, dependent on plastic telephones, circuit boards and cable insulation. Our entertainment and leisure relies on the unique combination of characteristics offered by plastics in sports equipment and clothing, CDs, video and audio tape, television and cinema - indeed you wouldn't be able to read this over the internet without plastics!
IMPORTANCE AND HISTORY
IMPORTANCE AND HISTORY
• The first man-made plastic was created by Alexander Parkes who publicly demonstrated it at the 1862 Great International Exhibition in London.
• The material called Parkesine was an organic material derived from cellulose that once heated could be molded, and retained its shape when cooled.
IMPORTANCE AND HISTORY
Did you know?
For every seven trucks needed to deliver paper grocery bags to the store, only one truck is needed to carry the same number of plastic grocery bags! Imagine the cost savings with today's high cost of fuel. Plastic lumber, made with recycled plastic packaging material, holds nails and screws better than wood, is virtually maintenance free, and lasts for 50 years. The number of plastics recycling businesses has nearly tripled over the past several years, with more than 1,700 businesses handling and reclaiming post consumer plastic products.
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CHARACTERISTIC OF PLASTIC• Most plastics are man-made materials with the ability to:-i. Flowii. take shape iii.Solidity
• Unlike metals, plastics are:-i. light in weightii. pleasant to touchiii.easy to form
• Complicated shapes are easily reproduced by:-i. Mouldingii. casting
CHARACTERISTIC OF PLASTIC
• They found their important roles in:-
• agriculture• appliances• clothing• construction• electronics• furniture• packaging• transportation KEMBALI
ADDITIVES
• Various forms of additives are put into basic polymers. The type and quantity varies according to the plastic required.
ADDITIVES
• Without additives, plastics would not work, but with them they can be made safer, cleaner, tougher and more colourful.
• Additives cost money, of course, but by reducing production costs and making products last longer, they help us to save money and conserve the world's precious raw material reserves.
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PLASTICISERS
• Added to make the basic polymer more flexible and process-able, they lower the softening temperature and improve the strength. Certain properties can only be achieved by adding a mixture of different plasticizers.
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FILLERS
To improve the physical properties of the plastic mix, Substances such as:-•wood•asbestos flour •Chalk•glass in fiber form•carbon fiber•synthetic fiber
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STABILIZERS
• Added to give stability to the polymer and the color dyes or
pigments, they present their properties from being destroyed when processed at high temperatures and fast production rates.
STABILIZERS
• In order for a plastic to have a long and useful life in any application, the properties of that plastic should change as little as possible with time. Stabilizers are added, usually in small quantities, to counter the effects of aging.
• Because all carbon-based polymers are subject to oxidation, the most common stabilizers are antioxidants.
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LUBRICANTS
• Acts by reducing the adhesion of the plastic material cause the hot metal surfaces of the process equipment.
• Ethylenebis (stearamide) (EBS) is a plastic lubricant made by the reaction of one mole of EDA with two moles of stearic acid
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COLOURANTS
• Colourants Included giving visual appearance to the end products, especially in consumer products. Used also as a method of identification, a good example being the covering sheath on electrical cables. Plastics in their pure form are transparent, nearly colorless or dark brown
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USED OF PLASTICS
LIGHTWEIGHT STRUCTURES
The ability of plastics to be foamed has ledto a completely new concept of lightweight construction.Rigid methane foams are used in furniture and other structural applications because of its strength.
USED OF PLASTICSMETALLIZED PLASTICSMany plastics can be coated with a thin metal film to change their appearanc
or meet a functional requirement
HUMAN IMPLANTATION• An important breakthrough in surgery has been the use of plastics as
implantation in the human body. • Strong, tough, non-allergenic plastics are finding increased use as
replacements for defective blood vessels- and other damaged parts of the body.
• The softer silicon rubbers are also used for implantation, but mostly for cosmetic purposes.
USED OF PLASTICSMASS PRODUCTION• Due to the tremendous strides made in injection, compression andtransfer moulding plastic products are now being produced more quickly and in larger volumes. • Improved mechanization of automatic and semi-automatic machines plus improved moulding materials have brought about shorter cure cycles and a reduction in handling operations.
CHEMICAL RESISTANCEMany plastics can be used in specialized chemical-resistant applications. With few exceptions (such as fluorocarbons), most plastic materials areattacked by one or more chemicals. • But though vulnerable to some chemicals a specific plastic can be highlyresistant to several others. By careful material selection, lightweight, unbreakable plastics can be used to replace glass and stainless steel as chemical containers.
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CATEGORIES OF PLASTICS
• Most plastics when first synthesized are in the form of liquids, powders, granules or pellets.
• All of these plastics can be made to flow by applying heat to them.
• They are divided generally into two groups according to their characteristics after the processing stage.
• The two groups are:Thermo-setsThermoplastics
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SUMMARY OF TYPES OF PLASTIC
• Plastic is as varied as it is malleable. As a man-made substance, plastic can be created to almost any specifications, and each plastic type has its own particular functions and uses, from elastic to rigid. Here is a list of 10 plastics associated with injection moulding and their properties
• Acrylonitrile-Butadiene-Styrene, (ABS), Thermoplastic. ABS is often used in the automotive industry for consoles, panels, trims and vents. It is both strong and flexible, chemically resistant and has a relatively low manufacturing cost. It is also often used for boxes, gauges, housings, asthma inhalers and toys.
SUMMARY OF TYPES OF PLASTIC
• Allyl Resin, (Allyl), Thermoset polycondensate. Allyl is used chiefly as an adhesive for laminated materials. It hardens when cured, and compounds based on allyl prepolymers reinforced with fibers of glass, cloth or acrylic to improve its properties. This is an essentially colourless resin, and so can be made into a variety of colours.
SUMMARY OF TYPES OF PLASTIC
SUMMARY OF TYPES OF PLASTIC
• Allyl Resin, (Allyl), Thermoset polycondensate. Allyl is used chiefly as an adhesive for laminated materials. It hardens when cured, and compounds based on allyl prepolymers reinforced with fibers of glass, cloth or acrylic to improve its properties. This is an essentially colourless resin, and so can be made into a variety of colours.
SUMMARY OF TYPES OF PLASTIC
• Ethylene vinyl alcohol, (E/VAL), Thermoplastic polymer. This compound has been around in a mass-production capacity since 1945. It is isften used in packaging of textiles but is also used as a coating in construction as it has good barrier properties for gases and aromatic materials.
SUMMARY OF TYPES OF PLASTIC
• Liquid Crystal Polymer, (LCP), Thermoplastic. LCP is an expensive material, but it is very strong and is both chemically resistant and heat redardent. It is often used in electronics for connectors and in the medical industry as surgical devices.
SUMMARY OF TYPES OF PLASTIC
• Nylon (Polyamide 6(PA6); Polyamide 6/6(PA66); Polyamide 11+12(PA11+12), Nylon is a common material used in everyday products. It is strong, hardy and ranges in colour from milky-white to almost clear. Although used often, it can be expensive.
SUMMARY OF TYPES OF PLASTIC
• Polycarbonate, (PC), Thermoplastic polycondensate. This is a material that we come into contact with regularly. It is tough, stable and transparent. Used for bottles, car parts, housings and helmets to name but a few, this material is expensive, but often used in mass production.
SUMMARY OF TYPES OF PLASTIC
• Polyester, Thermoplastic or thermoset polycondensate. This is a hardy, rigid, heat- and chemical-resistant property. It is used for electrical components, gears, wheels and in the automotive industry.
SUMMARY OF TYPES OF PLASTIC
• Polystyrene, (PS), Thermoplastic polymer. Polystyrene can refer to two different types. General purpose (GPPS) polystyrene is the brittle, cheap material that is often used for packing products into boxes. High impact polystyrene (HIPS) is hardy, has impact toughness and is translucent. It is used from electrical components to food containers to toys.
SUMMARY OF TYPES OF PLASTIC
• Polyurethane, (PU), Thermoplastic or thermoset, (typically reinforced), polyadduct. This is a unique material as it offers a great amount of strength whilst also retaining a certain amount of elasticity. They are often used in foam products.
SUMMARY OF TYPES OF PLASTIC
• There is an incredible range of plastics available to the plastic injection moulding trade. Each retaining its own particular properties, strengths and weaknesses, it's no wonder we see items around us on a daily basis that have come to us through this process.
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KUIZ
1. Most plastics are man-made materials with the ability to ?2. Explain function of additive and plasticisers 3. Name two group of plastic4. Polyester, Thermoplastic used for ?5.List two used of plastic.
