Chapter 17, Problem 17.68AP

Interpretation Introduction

Interpretation:

The structure of the polymer formed by the reaction between two terephthalic acids and two glycerols has to be drawn.

Concept introduction:

Carboxylic acid: One $-OH$ group is attached to the carbonyl carbon atom of the compound. It is represented as $RCOOH$

Ester: One $-OR\text{'}$ group is attached to the carbonyl carbon atom of the compound. It is represented as $RCOOR\text{'}$. The hydrogen atom of $-COOH$ is replaced by an alkyl group.

Esterification reaction: Esters are prepared by the reaction of a carboxylic acid and an alcohol molecule with the elimination of water molecule. The addition of a strong acid such as ${\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}$ is used to increase the rate of reaction.

Here, the $-OH$ group is attached to the carbonyl carbon atom of the carboxylic acid is being replaced by $-OR\text{'}$ the in the alcohol forming ester and water.

Polyester: One $-COOH$ group of a carboxylic acid reacts with the one of the hydroxyl groups of a alcohol results in the formation of an ester between them. Repeated linking of more molecule results in the formation of a polymer with ester linkage called polyester.