Question

. Poly (trimethylene carbamate) is used in high-quality synthetic leather. It has the structure shown.

(a) What type of polymer is poly (trimethylene carbamate)?

(b) Is this a chain-growth polymer or a step-growth polymer?

(c) Draw the products that would be formed if the polymer were completely hydrolyzed under acidic or basic conditions.

Short answer

(a)It is a polyurethane.

(b) As with all polyurethanes, it is a step-growth polymer.

Step-by-step solution

Step-1. Explanation of part (a) and (b):

Poly (trimethylene carbamate) is a polyurethane. Polyurethanes refers to class of polymers which are composed of organic units joined by carbamate links. These are family of plastics, and they are durable, flexible and adaptable.

Poly (trimethylene carbamate) is a step-growth polymer and undergoes step-growth polymerisation in which formation of polymer occurs from bi-functional or multifunctional monomers.

Step-2. Explanation of part (c):

Poly (trimethylene carbamate) if completely hydrolysed under acidic or basic conditions, then it would result in the formation of amino alcohol and also carbon-dioxide will get released in this process. Cleavage of nitrogen-carbon bond occurs which gives rise to intermediates and these intermediates rearrange to form amino alcohol and carbon dioxide gas as release of gas increases entropy of the system, thus this process is favourable.