Textile polymers: Viscose rayon is chemically best described as which of the following materials?

Introduction / Context:
Viscose rayon is one of the earliest man-made fibers. Although produced by chemical processing, its polymer backbone is the same as natural cellulose. Understanding its chemistry helps distinguish it from derivative celluloses and synthetic polymers.

Given Data / Assumptions:

• Viscose process dissolves natural cellulose by forming a soluble xanthate.
• After spinning, the cellulose derivative is reconverted to cellulose in an acid bath.
• End fiber composition equals cellulose, not acetate or nitrate derivatives.

Concept / Approach:

Wood pulp or cotton linters are steeped in alkali, reacted with carbon disulfide to form cellulose xanthate (viscose dope), then extruded into an acidic coagulation bath. Regeneration cleaves the xanthate groups, yielding continuous filaments of pure cellulose—hence the term “regenerated cellulose.”

Step-by-Step Solution:

Verification / Alternative check:

Analytical tests (e.g., nitrogen content) distinguish cellulose acetate or nitrate (which contain acetyl or nitrate groups) from viscose rayon which lacks such substituents after regeneration.

Why Other Options Are Wrong:

Cellulose acetate / nitrate: These are different materials (acetate is used for fibers and films; nitrate is highly flammable). Polyester: PET (dacron/terylene) is unrelated to cellulose.

Common Pitfalls:

Confusing the viscose processing intermediate (cellulose xanthate) with the final fiber; assuming “semi-synthetic” equals “derivative cellulose” in composition.

Final Answer:

Regenerated cellulose