Question

What is Modacrylic?
(A) Modified acrylic
(B) Natural fibre acrylic
(C) Acrylic and Polyester
(D) None of the above

Answer 1

Hint: Modacrylic is a copolymer which uses acrylonitrile as a base, same as acrylic. It is an advanced version of acrylic polymers.

Complete step by step solution:
Let us start from the very foundation of this question, which is acrylic fibres. These are synthetic polymers which look and feel similar to wool. They are composed of a minimum of 85% acrylonitrile. Below, we have shown the structure of acrylonitrile-

As you can see, it is so named because of the presence of the nitrile group (-CN). Along with acrylonitrile, an acrylic fibre has a co-monomer which adds other properties so as to improve the overall quality. These properties can be increased dyeability and enhanced elastic properties so as to increase the overall endurance of the polymer.
As the name itself suggests, Modacrylic is a modified version of acrylic fibres. These polymers have other attributes in addition to those already present in acrylic fibres. To achieve this feat, Modacrylic polymers are made with additional units of monomers that impart specific properties to the overall polymer. We look into these special features in the following lines-
- The Modacrylic fibres are resistant to flames or combustion. It has been found experimentally that they are difficult to ignite and are also able to self-extinguish themselves.
- This synthetic polymer very nearly approaches the properties of the natural wool fibre in terms of warmth and comfort it provides.
- These fibres are resistant to weak mineral acids and bases and also to some organic solvents.
- They do not easily wrinkle and have high elasticity.

So, our answer to the question is option (A).

Note: Even if Modacrylic contains acrylonitrile just as acrylic fibres, they are very different from them. The properties are also flexible as long as we combine the right co-monomer. But it should be taken into account that these are synthetic fibres and become a threat to the environment if used extensively.