Which of the following statements are correct ?

Options

A. Alkyl resins are addition polymers
B. Polystyrene is a thermoplastic
C. Dacron is a fibre
D. Natural rubber behaves as thermosetting polymer.

Answer

To determine which statements are correct, let's analyze each option one by one:

### Step 1: Analyze Statement A
**Statement A:** Alkyl Regens are addition polymers.
- **Analysis:** Alkyl Regens are not addition polymers; they are actually condensation polymers. Addition polymers are formed by the addition of monomers with double bonds, while condensation polymers are formed through the elimination of small molecules (like water) during polymerization.
- **Conclusion:** **Statement A is incorrect.**

### Step 2: Analyze Statement B
**Statement B:** Polystyrene is a thermoplastic.
- **Analysis:** Polystyrene is indeed classified as a thermoplastic polymer. Thermoplastics can be melted and reshaped upon heating, which is characteristic of polystyrene.
- **Conclusion:** **Statement B is correct.**

### Step 3: Analyze Statement C
**Statement C:** Dacron is a fiber.
- **Analysis:** Dacron is a type of polyester fiber known for its strength and durability. It is commonly used in textiles and has a crystalline structure, which is typical for fibers.
- **Conclusion:** **Statement C is correct.**

### Step 4: Analyze Statement D
**Statement D:** Natural rubber behaves as a thermosetting polymer.
- **Analysis:** Natural rubber is a type of elastomer and behaves as a thermoplastic rather than a thermosetting polymer. Thermosetting polymers are cross-linked and cannot be remolded after curing, while natural rubber can be reshaped upon heating.
- **Conclusion:** **Statement D is incorrect.**

### Final Conclusion
Based on the analysis:
- **Correct Statements:** B (Polystyrene is a thermoplastic) and C (Dacron is a fiber).
- **Incorrect Statements:** A (Alkyl Regens are addition polymers) and D (Natural rubber behaves as a thermosetting polymer).

### Summary of Correct Statements
- **B and C are correct.**

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