Plastics are synthetically produced materials that are capable of being moulded and made into useful shapes such as bottles and flat sheets. They usually soften under heat and pressure so they can be forced into a mould. Some types of plastic are set into a hard solid form by the application of heat, causing a chemical reaction between the component substances.
Most plastics are light in weight, are good electrical insulators and are tough enough to have many domestic and industrial uses.
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