What is the role of benzoyl peroxide in addition polymerisation of alkenes? Explain its mode of action with the help of an example.
Role of benzoyl peroxide is to initiate the free radical polymerization reaction which can be easily understood by taking an example of polymerization of ethene to polyethene.
(i) Chain initiation
(ii) Chain propagation
(iii) Chain terminator step
Which factor imparts crystalline nature to a polymer like nylon?
Strong intermolecular forces like hydrogen bonding and linear structure that lead to close packing of chains and hence, imparts crystalline character. e.g., nylon
Name the polymer used in laminating sheets and give the name of monomeric units involved in its formation.
Urea formaldehyde resin is used for laminated sheets. The monomer of this resin is urea $\left(\mathrm{NH}_2 \mathrm{CoNH}_2\right)$ and formaldehyde $(\mathrm{HCHO})$
Which type of biomolecules have some structural similarity with synthetic polyamides? What is similarity?
Polyamides have structural repeatation of amide linkages which is similar to peptide bond as present in polypeptide chains of proteins.
Why should the monomer used in addition polymerisation through free radical pathway be very pure?
During free radical polymerisation, monomers should be very pure because even very trace amounts of impurities may act as inhibitors which leads to the formation of polymers with shorter length.