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 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 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 a Nozzle. 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)