Question

Which plastic is commonly used as carry bags?
A. Polythene
B. Polyester
C. PET
D. Acrylic

Answer 1

Hint: This plastic is made of straight molecule chains that branch very little, staying linear from beginning to end. This linear structure creates a very strong material, which is why the common grocery bag is light yet can hold many times its own weight without tearing.

Step by step explanation:
Polythene or polyethylene is a thermoplastic polymer consisting of long hydrocarbon chains. Polyethylene or polythene is the most common plastic. Its primary use is in packaging (plastic bags, plastic films, containers including bottles, etc.). So option (A) is correct.

Polyester is a synthetic fabric that's usually derived from petroleum. As it is costly so it is not used in carry bags. So option (B) is incorrect.
PET, which stands for polyethylene terephthalate, is a form of polyester (just like the clothing fabric). It is extruded or molded into plastic bottles and containers for packaging foods and beverages, personal care products, and many other consumer products. So option (C) is also incorrect.

Acrylic is a transparent plastic that has gained widespread use because it's ability to replace the glass. But The melting point for acrylic plastic is 160 degrees C, so they cannot withstand extreme temperatures. So option (D) is also incorrect.


So option (A) is correct.

Note: Polythene has low strength and hardness, but is very ductile and has good impact strength; it will stretch rather than break. Polyethylene is water resistant and durable, so it is longer lasting when exposed to the elements compared to other polymers. Some disadvantages of polythene bags:
- High thermal expansion.
- Poor weathering resistance.
- Subject to stress cracking.
- Difficult to bond.
- Flammable.
- Poor temperature capability.