Question

In flame retardant finishing of cotton fabric, the correct statement(s) is/are

• A. The finishing material forms an insulating layer around the fibre at a temperature above the fibre pyrolysis temperature
• B. The finishing material forms an insulating layer around the fibre at a temperature below the fibre pyrolysis temperature
• C. The finishing material crosslinks cellulose and alters the pyrolysis route
• D. The finishing material dehydrates the cellulose

Hint:

- Flame retardant finishes for cotton fabrics work by forming a protective layer and altering the cellulose structure to prevent ignition.
- Dehydration and crosslinking of cellulose help in making the fabric resistant to flame and pyrolysis.

Answer 1

The Correct Option is B

- Statement (A): The finishing material forms an insulating layer around the fibre at a temperature above the fibre pyrolysis temperature.
This is incorrect because the finishing is designed to work at lower temperatures to prevent the fibre from reaching its pyrolysis point.
- Statement (B): The finishing material forms an insulating layer around the fibre at a temperature below the fibre pyrolysis temperature.
This is correct because the flame retardant finishes work by forming a protective layer at temperatures below the pyrolysis threshold.
- Statement (C): The finishing material crosslinks cellulose and alters the pyrolysis route.
This is correct because crosslinking alters the structure of cellulose, making it more resistant to combustion.
- Statement (D): The finishing material dehydrates the cellulose.
This is also correct as the dehydration process prevents the cellulose from reaching the conditions where combustion starts.
Thus, the correct answers are (B), (C), and (D).