introduction of plastic.ppt

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CHAPTER 1

INTODUCTION TO PLASTIC



INTODUCTION TO PLASTIC

AIM:

1. KNOW IMPORTANCE OF PLASTIC

2. 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




• 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.




• 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!




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 withtoday'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.

KEMBALI




• Most plastics are man-made materials with the ability to:-

i. Flow

ii. take shape

iii.Solidity

•

Unlike metals, plastics are:-i. light in weight

ii. pleasant to touch

iii.easy to form

• Complicated shapes are easily reproduced by:-

i. Moulding

ii. casting




• 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 materialreserves.

KEMBALI



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.

KEMBALI



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.

KEMBALI



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

KEMBALI



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

KEMBALI



USED OF PLASTICS

LIGHTWEIGHT STRUCTURES

The ability of plastics to be foamed has led

to a completely new concept of lightweight construction.Rigid methane foams are used in furniture and other

structural applications because of its strength.



USED OF PLASTICS

METALLIZED PLASTICS

Many 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 forcosmetic purposes.



USED OF PLASTICS

MASS PRODUCTION

• Due to the tremendous strides made in injection, compression and

transfer 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 RESISTANCE

Many plastics can be used in specialized chemical-resistant applications.

With few exceptions (such as fluorocarbons), most plastic materials are

attacked by one or more chemicals.

• But though vulnerable to some chemicals a specific plastic can be highly

resistant to several others. By careful material selection, lightweight, unbreakable

plastics can be used to replace glass and stainless steel as chemical containers.

KEMBALI



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-sets

Thermoplastics

KEMBALI



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 andtoys.




• 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 canbe made into a variety of colours.





• 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.




• 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.




• 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.




• 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.




• 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 fromelectrical components to food containers to toys.




• 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.




• 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.

KEMBALI



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.

introduction of plastic.ppt

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