Polymer science — definition of rayon (regenerated fiber) In industrial polymer chemistry, the term “rayon” refers to synthetic fibers produced by chemically regenerating which natural precursor?

Introduction / Context:
Rayon is often called a “semi-synthetic” or “regenerated” fiber because it is made by chemically processing a natural polymer into a fiber-forming solution and then regenerating it as a filament. Understanding the parent material helps learners categorize fibers and predict properties such as moisture regain and dye affinity.

Given Data / Assumptions:

• Rayon is produced industrially via processes such as viscose, cuprammonium, and lyocell.
• Options include common polymer families and biopolymers.
• We are asked to identify the original precursor substance.

Concept / Approach:
Cellulose is a natural polysaccharide found in wood pulp and cotton linters. In the viscose route, cellulose is derivatized (e.g., to cellulose xanthate) and then extruded and regenerated back to cellulose filaments. Lyocell dissolves cellulose in N-methylmorpholine N-oxide and regenerates it directly. Rayon retains cellulose’s hydrophilicity and comfort attributes, distinguishing it from fully synthetic fibers like polyamides or polyesters.

Step-by-Step Solution:
Identify the key term “regenerated” which implies a natural polymer is chemically dissolved and reformed.Recall that all rayon variants regenerate cellulose as the final fiber.Select “cellulose” as the correct precursor.

Verification / Alternative check:
Standard textile references classify rayon under regenerated cellulose fibers (viscose rayon, modal, lyocell). Its chemical repeat unit in the final fiber is anhydroglucose, identical to cellulose.

Why Other Options Are Wrong:

• Lignin: abundant in wood but not the basis of rayon processes.
• Polyamides: fully synthetic (e.g., nylon), not regenerated cellulose.
• Ethylene glycol: monomer for PET polyester, unrelated to rayon.

Common Pitfalls:

• Confusing “synthetic” with “regenerated.” Rayon begins with a natural polymer.
• Assuming all man-made fibers are petrochemical-based.

Final Answer:
cellulose