Question

Assertion: acrylic fibers are also known as Orlon and Acrilan fabrics
Reason: it is used in making sweaters, socks and shawls.
A. both assertion and reason are correct and reason is correct explanation for assertion
B. Both assertion and reason are correct but reason is not correct explanation for assertion
C. Assertion is correct but reason is incorrect
D. Reason is correct but assertion incorrect

Answer 1

Hint: acrylic fibers are synthetic fibers made form a polymer polyacrylonitrile. A fiber is known as acrylic if it contains at least $35\% - 85\% $ $85\% $ acrylonitrile monomer. The first acrylic fibers were trademarked under the name Orlon.

Complete Step by step answer: Polymers are a substance consisting of very large molecules or macromolecules, composed of many repeating subunits. The biers that are found naturally are known as natural polymers. On the other hand polymers that are man-made are known as synthetic polymers. Both natural and synthetic polymers play an essential role in everyday life.
Acrylic fibers are synthetic fibers, and are made of polymer polyacrylonitrile. Polyacrylonitrile is also known as polyvinyl cyanide. It is a semi crystalline organic polymer, with molecular formula ${({C_3}{H_3}N)_n}$ . Almost all polyacrylonitrile resins are copolymers made from a mixture of monomer with acrylonitrile as the main monomer.
For a fiber to be called as acrylic it must contain at least $85\% $ of acrylonitrile monomer.
The polyacrylonitrile are made by free radical polymerization. Homopolymers of polyacrylonitrile have been used as fiber used in hot gas filtration systems, sails in yatch and fiber reinforced concrete. But mostly copolymers containing polyacrylonitrile are used as fibers to make knitted clothing, like socks, sweaters as well as outdoor products like tents. If a label says acrylic then that means that fiber is made out of some copolymer of polyacrylonitrile with at least $85\% $ of acrylonitrile. Usually they are copolymers of acrylonitrile and methyl acrylate or acrylonitrile and methyl methacrylate. Also sometimes there are copolymers of acrylonitrile and vinyl chloride.
So the acrylic fiber is known as orlon and acrilan fabrics and this fiber is used to make warm clothes like sweaters, socks etc. both the reason and assertion are correct. But because we can use acrylic fiber to make warm sweaters and socks they are not named as orlon, orlon was a trade name.

 Hence the correct option is A.

Note: When the composition of acrylonitrile, vinylidene chloride or vinyl bromide is from $35\% - 85\% $ the modacryl is modified acrylic fiber has formed. This fiber has flame retardant or fire resistance properties. And hence used in protective clothing