What are the methods for synthesizing polymers?

Polymers are synthesized through methods such as addition polymerisation, condensation polymerisation, and copolymerisation.

Addition polymerisation is a process where monomers with double or triple bonds combine to form a polymer. The double or triple bond of the monomer is broken and the electrons are used to form new single bonds with other monomers. This process continues in a chain reaction, adding more and more monomers to the growing polymer chain. Polyethylene and polypropylene are examples of polymers made by addition polymerisation.

Condensation polymerisation, on the other hand, involves monomers with two or more reactive groups. When these monomers react, they join together and lose small molecules like water, hence the name 'condensation'. This process continues, forming a long chain polymer. Examples of polymers made by condensation polymerisation include nylon and polyester.

Copolymerisation is a process where two or more different types of monomers are combined to form a polymer. This method allows for a wide range of properties in the resulting polymer, as the properties can be influenced by the types and proportions of monomers used. This method is used to make a variety of polymers, including acrylonitrile butadiene styrene (ABS), which is used in Lego bricks.

In all these methods, the reaction conditions such as temperature, pressure, and the presence of catalysts can greatly influence the properties of the resulting polymer. For example, low-density polyethylene and high-density polyethylene are both made from ethene monomers, but under different conditions, resulting in polymers with different properties. Understanding these methods of polymer synthesis is crucial in the field of materials science, as it allows for the creation of new materials with tailored properties.