Answer
🔬 Understanding Polymer Rigidity in Radical Polymerization
🧩 Key Requirements for High Rigid Strength
For a polymer to have high rigid strength, it generally exhibits:
- Strong intermolecular interactions — such as hydrogen bonding or van der Waals forces
- Crystallinity or high degree of order — leading to increased density and resistance to deformation
- Limited chain mobility — often due to bulky or symmetrical substituents that encourage tight packing
❌ Incorrect Options Explained
✘ No interactions between polymer chains — This would result in a soft, flexible material, not a rigid one.
✘ A random arrangement of side chains — This leads to amorphous, less ordered structures and reduces rigidity.
✅ Correct Answer
✔ A highly organised structure — Polymers with crystalline or semi-crystalline regions have stronger, stiffer mechanical properties.
📘 Summary
Radical polymerisation can produce rigid polymers if the monomer units and reaction conditions promote ordered packing and strong interchain forces. Tacticity (stereoregularity), crystallinity, and interchain interactions all contribute to rigidity.