Chapter 26, Problem 26.73P

Interpretation Introduction

(a)

Interpretation:

Dry-erase boards, or whiteboards, in classrooms, consist of a network polymer similar to Bakelite that is made from formaldehyde and melamine. A structure of the polymer formed is to be drawn.

Concept introduction:

The anime ( ${\text{-NH}}_{\text{2}}$ ) group is nucleophilic towards the carbonyl carbon, when it is treated with an aldehyde, in presence of acid as the catalyst, corresponding primary alcohol will be formed. The melamine also possesses ${\text{-NH}}_{\text{2}}$ a group and reacts with an aldehyde to form the corresponding alcohol in the presence of acid. In acidic conditions alcoholic group also eliminated in the form of water and generates carbocation.

Interpretation Introduction

(b)

Interpretation:

Dry-erase boards, or whiteboards, in classrooms, consist of a network polymer similar to Bakelite that is made from formaldehyde and melamine. It is to be explained why this polymer suitable for use in whiteboards.

Concept introduction:

The anime ( ${\text{-NH}}_{\text{2}}$ ) group is nucleophilic towards the carbonyl carbon, when it is treated with an aldehyde, in presence of acid as the catalyst, corresponding primary alcohol will be formed. The melamine also possesses ${\text{-NH}}_{\text{2}}$ a group and reacts with an aldehyde to form the corresponding alcohol in the presence of acid. In acidic conditions alcoholic group also eliminated in the form of water and generates carbocation. Network polymers are insoluble in most of organic as well as inorganic solvents.