Question

Crystallization is favored in polymer melts when the chain entanglement is ............. and only polymers with ............. molecular arrangement can crystallize.

• A. maximum, ordered
• B. minimum, random
• C. maximum, random
• D. minimum, ordered

Hint:

For effective crystallization, polymers must have low chain entanglement and be able to adopt an ordered molecular structure, which aids in the formation of crystalline regions.

Answer 1

The Correct Option is D

Crystallization in polymer melts is the process where the polymer chains align and organize themselves into a regular, repeating structure, known as a crystal lattice. The conditions that favor crystallization depend on two factors: the degree of chain entanglement and the molecular arrangement.
- Chain entanglement refers to the interlocking or intertwining of polymer chains. When entanglements are minimum, the polymer chains can move more freely and align themselves in an ordered manner, which is conducive to crystallization.
- Molecular arrangement refers to the regularity and symmetry of the polymer chains. Only polymers with an ordered molecular arrangement can crystallize because an organized structure is required for the chains to form a crystalline lattice.
Thus, crystallization is favored when the chain entanglement is minimum and the molecular arrangement is ordered, making the correct answer (D) minimum, ordered.