![]() Which of the following is not a condensation polymer ?.Which of the following is a natural polymer?.The monomer used to produce orlon is…..Poly-β-hydroxybutyrate-co-β hydroxyvalerate….Among the following, the branched-chain polymer is….The monomer used in Novolac, a polymer used in paints….Which one of the following is amorphous….Block copolymers have covalent bonds between two monomeric chains/blocks.This wide range of applications is possible due to the highly modified chemical properties of copolymers which make them usable. Copolymers have a vast range of applications in many fields.nylon -6-6- ,spandex,High strength polystyrene, SBS rubber,etc all have various uses.Different classes of copolymers include block,graft,star,brush,comb,periodic,statistical and alternating copolymers.Copolymers have more than one monomeric unit/species joined together in either linear or branched fashion.Nylon -6-6- is frequently used in textiles, carpeting, as an engineering material in bearings and gears due to its self-lubricating properties.Spandex used as synthetic fibre is a block copolymer, other block polymers like polyester and polyamide TPEs have applications in hose tubing, sports goods and automotive components.Graft polymers can be used as membranes to separate gas and liquids, they can also be used in emulsifiers and biomedical applications.Acrylic copolymers are used for nail polish, eyeliners, lipsticks, sunscreens, skin lotions, etc.Copolymers of hygroscopic and hydrophilic polymers are frequently used in cosmetics, drug delivery and self-polishing paint applications.Poly β-hydroxybutyrate – co-β-hydroxy valerate Several polymeric chains can be connected into the same central core unit.īrush and comb copolymers are other kinds of branched copolymers. Here, the main chain can be covalently bonded to one or more side chains.Įxample: Polystyrene chains can be grafted into polybutadiene. Special branched copolymers in which side chains are structurally different from the main chain. Examples Acrylonitrile butadiene styrene (SBS rubber) They can be diblock or triblock copolymers. The intermediate unit where they join is called a junction block. When two or more homopolymer chains are joined by covalent bonds the resultant polymeric chain is called a Block copolymer. Moreover, if the probability of finding a given monomer at a particular point in a chain is equal to its mole fraction in the chain then it can be called a random polymer.Įxample: Rubbers made from styrene-butadiene copolymers, resins from styrene-acrylic etc. When the sequence of monomeric units follows a certain statistical rule, it is called a statistical copolymer. The general formula for the monomers A and B can be given asĪlternating Copolymers Statistical Copolymers ![]() These copolymers have a regular, repetitive and alternating arrangement of two monomeric species. Branched copolymers are sub-classified into grafted and star-shaped copolymers. The basic two types are:Īgain the linear copolymers contain a single main chain and are sub-classified as alternating, statistical and block copolymers. Similarly, Nylon 6-6 is a copolymer of hexamethylene diamine and adipic acid.Ī copolymer has at least two types of monomers, so on the basis of how these monomers are arranged in the chain, the copolymers are classified into certain types. The above copolymerisation of 1,3-Butadiene and styrene gives the Butadiene-Styrene copolymer which is quite tough and a good substitute for natural rubber and is used to manufacture auto tyres, floor tiles, cable insulations, footwear components etc. It is just like a hybrid version of a polymer where the best properties of different species of monomers get together to give a better product.Ĭonsider the following copolymerisation reaction below. Copolymerisation infuses better properties than what is present in a homopolymer. In the above case, it is a bipolymer copolymer. As we already know copolymerisation is a polymerisation reaction (step-growth or chain growth) where multiple species of monomers are polymerised together.Īs it is clear from the picture above that a copolymer is a mixture of different species of monomers. There are basically two types of polymerisation reaction:Ĭopolymerisation can be done by both methods.
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