In polymer chemistry, Orlon is the trade name for a synthetic fibre that is a polymer of which monomer?

Introduction / Context:
This question belongs to the topic of synthetic polymers and trade names of common fibres. Examinations often test whether you can link a commercial name to its underlying monomer and polymer type. Orlon is a well known trade name used for an acrylic fibre. Knowing its monomer helps you categorise it as a type of addition polymer and understand its properties and uses in fabrics and textiles.

Given Data / Assumptions:

• The polymer in question is marketed under the trade name Orlon.
• Orlon is described as a synthetic fibre used in textiles.
• You are given several possible monomers or related polymer types such as Dacron, acrylonitrile and polyamide nylon.
• The task is to identify the correct monomer from which the polymer known as Orlon is produced.

Concept / Approach:
Orlon is an acrylic fibre. Acrylic fibres are typically polymers of acrylonitrile, a monomer with the structure CH2=CHCN. During polymerisation, the double bond opens and forms a long chain polyacrylonitrile. Trade names like Orlon are used by companies for marketing, but examination questions expect you to connect them with their chemical monomers. Dacron, on the other hand, is a trade name for polyethylene terephthalate, a polyester formed from ethylene glycol and terephthalic acid. Polyamide nylon is a condensation polymer formed from diamines and dicarboxylic acids. Therefore only one option matches the known chemistry of Orlon.

Step-by-Step Solution:
Step 1: Recall that Orlon is a trade name associated with acrylic fibres. Step 2: Acrylic fibres are made primarily from the monomer acrylonitrile, which has a carbon carbon double bond and a nitrile group. Step 3: Through addition polymerisation, many acrylonitrile molecules join together to form polyacrylonitrile, the main component of Orlon. Step 4: Examine the options. Dacron is a completely different polymer, a polyester, and not related directly to Orlon. Step 5: Polyamide nylon refers to a family of condensation polymers, such as nylon 6 and nylon 6,6, based on amide linkages. Step 6: None of the above is not correct because acrylonitrile is a listed option and is in fact the correct monomer. Step 7: Hence, Orlon is a polymer of acrylonitrile.

Verification / Alternative check:
You can confirm this by checking typical examples from polymer chapters in textbooks. Common trade names are often grouped: Teflon from tetrafluoroethene, Orlon from acrylonitrile, Dacron from terephthalic acid and ethylene glycol, Bakelite from phenol and formaldehyde. Orlon is always placed under acrylic fibres and described as polyacrylonitrile. Its uses include sweaters, blankets and carpets where wool like properties are desired. This matches the information that Orlon is a synthetic acrylic fibre derived from acrylonitrile monomer through chain growth polymerisation.

Why Other Options Are Wrong:
Dacron is not a monomer at all but a trade name for a polyester polymer, so it cannot be the monomer of Orlon. Polyamide nylon is also a class of polymers, not a monomer, and is based on repeating amide linkages from diamines and dicarboxylic acids. None of the above would only be appropriate if none of the other options matched the known chemistry of Orlon, but acrylonitrile clearly does. Therefore these options do not correctly describe the monomer used to prepare Orlon.

Common Pitfalls:
Learners sometimes confuse trade names and polymer classes, for example mixing up Dacron and Orlon or thinking that any synthetic fibre must be a type of nylon. Another mistake is to believe that terms like Dacron or Orlon represent monomers rather than polymers. To avoid such confusion, make a small table linking trade names, monomers and polymer classes while studying. Remember that Orlon is associated with acrylic fibres and acrylonitrile, whereas Dacron is linked with polyester and nylon with polyamides.

Final Answer:
Orlon is a polymer formed from the monomer acrylonitrile.