Silicone polymers can be synthesized in liquid or gel or resin forms. There properties depend on
(A) the length of the polymeric chain
(B) the degree of polymerization and cross linking of the polymeric chains
(C) the degree of branching chains
(D) all of these

The intermediate never formed during chain growth polymerization is

What type of forces are responsible for the formation of (a) Cross linking of polypeptide chains (b) alpha -helix formation (c) beta -sheet structure.

Polymers are made up of small molecules called monomers. Polymer which are formed by one type of monomer is called homopolymer and which are formed by more than one type of monomers are called co-polymers. Natural polymers are biodegradable whereas synthetic polymers may or may not be. Addition or chain growth polymerization involves the repeated addition of monomers to the polymer chain. The monomers are unsaturated compounds and this type of polymerization takes place by ionic (cationic or anionic) as well as free radical mechanism. Condensation or step growth polymerization involves a series of condensation reactions between twomonomers. Each monomer normally contains two functional groups. Branch chain polymers may be condensation or addition but cross linked polymers are always condensation polymers. Which of these are natural polymers?