As alkenes are unsaturated, they are useful for making other molecules,especially polymers(long chain moloecules). Many small alkene molecules (monomers) join together to form polymers this is polymerisation.
Polymers such as poly(ethene) and poly(propene) are made in this way.
For exapmle, slime with different viscosities can be made from poly(ethenol).The viscosity of the slime depends on the temperature and concentrations of poly(ethanol) and borax from which it's made.
The materials commonly called plastics are all synthetic polymers.
Many polymers are not biodegradable, so they are not broken down by microbes. This can lead…