Condensation Polymers: This type of polymers is generated by the condensation of two monomer units with the loss of small molecules such as H2O, HCl, and NH3 etc. Here the monomer units must have two functional groups in order to condensation reaction took place. Dacron®, nylon 6 and nylon 66 are few examples for condensation polymers.
Copolymer: If the polymer chain is formed from only one type of monomer units are called homopolymers. Alternatively, two of more different monomer units can combine to form a polymer chain is called copolymers.
There are four types of copolymers are known. First, alternate arrangement of monomer units results alternating copolymer. Secondly, block arrangement of monomer units result block copolymers. Thirdly, a random arrangement of monomer units results random copolymers and finally, a graft copolymers results by one type of monomer units are arranged at the branches of the chain and the another type of monomer units still reside at the main chain.
Polyamides: This type of polymers is formed by the result of generation of amide bonds in the polymerization reaction. Nylon 6 and nylon 66 are important examples for this type of polymers nylon 6 is synthesized from ϵ-caprolactam, which on heating decomposes into 6-aminohexanoic acid that polymerizes into nylon 6. Here the number 6 represents the number of carbon atoms present in the monomer unit.
Nylon 66 is produced by the condensation reaction between two monomer units adipic acid and 1,6-hexanediamine in the presence of heat. This is formed from a six-carbon diacid and a six-carbon diamine.
Polyesters: This type of polymers is generated by the result of formation of ester bonds in the polymer chain by the condensation reaction between two monomer units. Dacron® is a well-known polyester, synthesized by the transesterification of dimethyl terephthalate with ethylene glycol.
Similarly, trans esterification of dimethyl terephthalate with 1,4-di(hydroxymethyl)cyclohexane results Kodel® polyester.
Polycarbonates:This is an example for condensation of step-growth polymer. Here the polymer chain is linked together by carbonate bonds. Lexan®, a polycarbonate formed by the condensation reaction between the two monomers phosgene and bisphenol A. This is used for manufacturing bulletproof windows.
Polyurethane: A carbamate functional group is synthesized by the addition reaction of an alcohol with an isocyanate molecule. This is also called as urethane. If a polymer chain is linked together by urethane bonds are called as polyurethane. Typically, polyurethanes are prepared by the addition reaction of diol monomers with diisocyanate monomers. Polyurethane in the form of foams has been used for furniture stuffing, carpet backings and insulations.
