Synthetic polymers

The polymers that do not form naturally and can be

manufactured from organic compounds are called synthetic

polymers.

• Roles of plastic bags are made of polyethylene .It is used to make , food storage containers and bottles.

• Polyethylene is formed by breaking the double bonds of many ethene molecules

and allowing the molecules to reform as a polymer

• Table 14-3 page 363

• polystyrene

• Polyvinyle chloride

• PVC

• Do you know that making plastic soft drink bottles is similar to blowing up a ballon?

• Page 364 figure 14-10

A synthetic fiber

• A synthetic fiber is a strand of a synthetic polymer. Some synthetic fibers have amazing properties.

• For example: Kevlar is five times stronger than a

similar strand of steel.

Fabrics with new properties are made by weaving natural fibers. Such as cotton and silk, with synthetic fibers.

Look at the label of a permanent- press shirt, you will see that the fabric is a mixture of natural and synthetic fibers.

How nylon fibers are manufactured?• Nylon chips are heated until they melt.• The melted nylon is pumped in to a

high pressure chamber.• It is then forced to the tiny openings of

aNozzle.• As it cools the nylon forms long

strands.

• The raw material – the hydrocarbon and organic compounds used to produce plastics and synthetic fibers .

• Most of them are found in petroleum – crude oil – and in natural gas.

Composite

• Is a mixture of two materials , one embedded in the other.

• Fiber- glass ( cars with fiber glass bodies)