Question

(a) Nomex®, a strong fire-resistant fabric, is a polyamide made from meta-phthalic acid and meta-diaminobenzene. Draw the structure of Nomex.

(b) Kevlar®, made from terephthalic acid (para-phthalic acid) and para-diaminobenzene, is used in making tire cord and bulletproof vests. Draw the structure of Kevlar.

Short answer

a)

b)

Step-by-step solution

Introduction

Nomex® and Kevlar ® are Aramids or aromatic polyamide, a family of nylons. Their blends are used to make fireproof clothing. They are heat-resistant and have strong synthetic fibers.

(a) Nomex

Nomex® has meta-phenylene groups, in which the amide groups are attached to the phenyl ring at the 1 and 3 positions.

(b) Kelvar

Kevlar ® is a polyamide, in which all the amide groups are separated by para-phenylene groups, which means, the amide groups attach to the phenyl rings opposite to each other, at carbons 1 and 4.