Compared with nylon fibres, Dacron (Terylene) polyester fibres generally exhibit which combined property trends in routine textile service and chemical exposure?

Introduction / Context:
Polyester (Dacron/Terylene) and nylon are the two most common synthetic fibres. Their comparative behavior under heat, chemicals, and dyeing affects fabric engineering, apparel finishing, and industrial textile selection. Recognizing the overall trends helps with appropriate material choice.

Given Data / Assumptions:

• Polyester is PET; nylon refers to aliphatic polyamides (e.g., nylon-6, nylon-66).
• We compare heat resistance, acid/alkali resistance, and dyeability.
• General textile conditions (not extreme lab conditions) are assumed.

Concept / Approach:

Polyester typically has better heat resistance and dimensional stability than nylon under ironing or hot-washing conditions. Chemically, polyester is more resistant to many acids but is susceptible to alkaline hydrolysis. Dyeability of PET is more challenging due to its hydrophobic, highly crystalline nature and lower amide hydrogen bonding sites compared to nylon; it often requires carriers or higher temperatures (disperse dyes) to achieve deep shades.

Step-by-Step Solution:

Verification / Alternative check:

Textile finishing guides corroborate that PET shows good hot pressing tolerance and acid resistance but requires disperse dyes and elevated temperatures, while strong alkalis can hydrolyze ester linkages.

Why Other Options Are Wrong:

Each single statement is true; collectively they form the most complete answer, hence “All of the above”.

Common Pitfalls:

Assuming one property (e.g., toughness) predicts chemical resistance; ignoring different dye classes used for nylon vs. polyester.

Final Answer:

All of the above