Question

Which theory is based on the assumption that the rigidity of the resin arises from intermolecular friction binding the chains together in a rigid network? On heating, these frictional forces are weakened to allow the plasticizer molecules to lubricate the chains?

• A. Lubrication Theory
• B. Gel Theory
• C. Free Volume Theory
• D. Mechanistic Theory

Hint:

The Lubrication Theory involves the weakening of intermolecular friction through heating, allowing plasticizers to lubricate and improve the flexibility of resin materials.

Answer 1

The Correct Option is A

Step 1: Understanding Lubrication Theory
The Lubrication Theory is based on the idea that the rigidity of the resin material arises due to intermolecular friction between the polymer chains. This friction forms a rigid network, which limits the movement of the chains. When the resin is heated, these frictional forces are weakened, allowing plasticizer molecules to slip in and lubricate the polymer chains, thereby making the material more flexible.

Step 2: Conclusion
Lubrication Theory explains how heating decreases friction and allows the plasticizer to improve flexibility by lubricating the chains, which directly corresponds to the description provided in the question.

Step 3: Quick Tip
The Lubrication Theory helps explain how temperature and plasticizers work to increase flexibility in materials like resins and polymers.