POLYSTYRENE

Presentation by –Zagros A Omar

OutlineHISTORY N

INTRODUCTION

SYNTHESIS OF POLYSTYRENE

PROPERTY

FORMS PRODUCED

PPLICATION

ADVANTAGES & DISADVANTAGES

zagrosfaqeanay @gmail.com

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Discoveries of Polystyrene-1839: first synthesize by German pharmacist, Eduard Simon.

• Polystyrene is a hard, stiff, brilliantly transparent synthetic resin produced by the polymerization of styrene.

• It is widely employed in the food service industries as rigid trays and containers.

• Polystyrene is also co polymerized or blended with other polymers lending hardness and rigidity to a number of important plastic and rubber products.

INTRODUCTION

Synthesis of PolystyreneA. Polystyrene: a plastic polymer made from monomer units of styrene, a liquid hydrocarbon that is commercially manufactured from petroleum, but can be melted at higher temperature for molding than resolidified.

The chemical reaction for the synthesis of polystyrene is shown on top

Synthesis of PolystyreneBefore we can synthesize polystyrene, we must make its monomer styreneDirect catalytic dehydrogenation of ethylbenzene is the main manufacturing course of styrene

Synthesis of PolystyreneOnce

styrene is produced, nearly 65% of it is then used to produce polystyrene. The overall reaction that describes the styrene polymerization is shown here.

• Polystyrene is a synthetic aromatic polymer made from the monomer styrene.

• It can be solid or foam.• Low density.• Good thermic insulant.• Flammability.• Poor barrier to oxygen and water vapour.• Has relatively low melting point.

PROPERTIES

• As a thermoplastic polymer, polystyrene is in a solid state at room temperature but it flows if heated about 100o C.

• This temperature behaviour is exploited for extrusion and also for molding and vacuum forming since it can be cast into molds with fine details

• Sheet or molded polystyrene• Foams• Expanded polystyrene • Extruded polystyrene foam• Copolymers

FORMS PRODUCED

Mainly used for insulation.

Types of insulations:• Below grade insulation• Cavity wall insulation• Concrete applications• Exterior insulation and finish systems(EIFS)• Radiant floor insulation• Roof insulation• Structural insulated panels

APPLICATION:

• It is a cost effective durable and energy efficiency solution for insulation applications.

• It is an ideal material to stop energy loss.• For poured in place and precast concrete systems reduces

the requirement for concrete and overall weight.

ADVANTAGES:

• Light weight .• High strength.• Excellent adhesion to concrete.

CONCRETE APPLICATIONS

• Polystyrene has a negative impact on environment.• These are produced using blowing agents that form bubbles and

expand the foam. Polystyrene is usually made with HFC which have global warming potentials of approximately 1000-1300 times that of carbon dioxide.

• Polystyrene discarded in the environment does not break down for hundreds of years and takes up precious space in landfill.

• Easily blown by the wind ending up as litter in the environment where it can harm animals and marine life.

• Animals can mistake polystyrene for food and it can be lethal to birds and sea life that swallow it.

Coastal debris including polystyrene in Japan

DISADVANTAGES

Referenceshttp://www.minddisorders.com/Br-Del/Caffeine-related • http://www.chevroncars.com/learn/food-recipes/coffee-children

• http://www.cfsan.fda.gov/~dms/wh-preg2.html http://www.erowid.org/chemicals/caffeine/caffeine.shtml (accessed: 2 April 2003).

• . http://www.doh.gov.uk/sacn/pdf/200106caffeine.pdf (accessed: 2 April 2003).

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ANY QUESTION?

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Time for discussion.&

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