14.8 (a) Synthetic polymers

14.8 (a) Synthetic polymers

Uses of plastics:

Polymer Example of uses
polythene plastic bags and gloves, clingfilm (low density), mugs,

bowls, chairs, dustbins (high density)

polychloroethane (PVC) water pipes, wellingtons, hoses, covering for  electricity

cables

polypropene crates, ropes
polystyrene used as expanded polystyrene in fast-food   cartons,

packaging, and insulation for roofs and walls

Teflon coated on frying pans to make them non-stick, fabric

protector, windscreen wipers,  flooring

nylon ropes, fishing nets and lines, tents, curtains
Terylene clothing (especially mixed with cotton), thread

Pollution problems from plastics:

-choke birds, fish and other animals that try to eat them. Or they fill up the animals’ stomachs so that they can’t eat proper food, and starve to death.

-they clog up drains and sewers and cause flooding.

-they collect in rivers, and get in the way of fish. Some river beds now contain a thick layer of plastic

-they blow into trees and onto beaches. So the place looks a mess. Tourists become put off.

Deduce the structure of the polymer product from a given alkene and vice versa (I just found as many as I could from the power points on moodle):

(For making nylon and Terylene: details of manufacture and mechanisms of these polymerisations are not required.) Making nylon (a polyamide):

The monomers are:

But they are represented like this:

No double bonds break. Instead, single bonds break, and new single bonds form. The monomers are able to join to each other by eliminating a small molecule: hydrogen chloride. This reaction continues at each the two monomers. Thousands of molecules join together, giving a macromolecule:

Making Terylene (a polyester): The monomers are:

The monomers join by eliminating a water molecule. Thousands of molecules join up, giving a macromolecule.