What is produced as a by-product during the condensation polymerisation of phenols and formaldehyde?

During the condensation polymerization of phenols and formaldehyde, the process involves the reaction between these two components to form a polymer, specifically phenolic resins. As the polymer chains grow, small molecules are eliminated as by-products of the reaction.

In the case of phenols reacting with formaldehyde, water is produced as a by-product. This occurs because the reaction involves the hydroxyl groups (–OH) of phenols and the aldehyde groups (–CHO) of formaldehyde, leading to the formation of ether linkages and the elimination of water.

Understanding this process helps highlight the importance of understanding the nature of condensation reactions in polymer chemistry, where the formation of water (or other small molecules) is a common characteristic. The focus on the production of water as a by-product is crucial, as it not only contributes to the overall stoichiometry of the reaction but also affects the properties and curing mechanisms of the resulting phenolic resins.