Applications of polyurethane (PU): identify the option that is NOT a typical end use for polyurethane materials.

Introduction / Context:
Polyurethane chemistry produces a family of materials from soft foams to tough elastomers and high-solids coatings. Recognising where PU dominates—and where other polymers are preferred—helps in materials selection.

Given Data / Assumptions:

• PU forms via isocyanate + polyol reactions.
• Common uses include flexible/rigid foams, coatings, adhesives, and elastomeric parts.
• Beverage bottles are typically PET or sometimes HDPE, not PU.

Concept / Approach:
Processability and regulatory/food-contact requirements make PET the bottle material of choice (clarity, barrier, strength). PUs excel in cushioning, protective coatings, footwear midsoles, and bonding applications but are not blown into beverage bottles.

Step-by-Step Solution:
List core PU applications: foams, coatings, adhesives.Compare to bottle production (stretch-blow moulded PET).Select “bottles for beverages” as the exception.

Verification / Alternative check:
Packaging industry standards specify PET for most beverage bottles due to clarity and carbonated-drink pressure resistance.

Why Other Options Are Wrong:
(a), (b), (c): all are mainstream PU uses.

Common Pitfalls:
Confusing “polyurethane elastomer parts” with blow-moulded packaging; very different processing routes.

Final Answer:
Bottles for beverages