Chapter 15: Polymers

Ans: While manufacturing tyre rubber, 5 % sulfur is used as a crosslinking agent. A natural linear polymer of 2-methyl-1, 3-butadiene becomes hard on treatment with sulfur and forms vulcanised rubber. The structure of the product formed is,

Ans: Addition polymers formed by the polymerization of a single monomeric species are known as homopolymers. The above-given polymer is a homopolymer.

Ans: Addition polymers formed by the polymerization from two different monomers are co-polymers. The above-given polymer is a co-polymer. For example Buna-N, Buna-S.

Ans: This is a type of chain-growth polymerization. The molecules of the same monomer or different monomer are added together to form this type of polymer.

Ans: The polymer shown above is cross-linked or network polymer. They are formed from bi or tri-functional monomers that contain strong covalent bond between polymer chains.

Ans: The cis-polyisoprene molecule is made up of several chains that are held together by weak van der Waals interactions and has a coiled structure. Thus, it can be stretched like a spring and exhibits elastic properties.

Ans: Rubber is a natural polymer. It is also known as an elastomer due to its elastic properties. It is manufactured from rubber latex.

Ans: Enzymes are biocatalysts that are present in the body. They are basically proteins, and they are also considered as polymers.

Ans: Yes, nucleic acids, proteins, and starch can be considered step growth polymers because this type of polymerization involves a condensation reaction between two monomers. Loss of simple molecules such as water, alcohol results in this type of polymerization and it results in the formation of high molecular mass polymers.

Ans: Melamine formaldehyde polymer is formed by the condensation polymerization of melamine and formaldehyde.  This is resin intermediate.