The degreen of crystallinity of which of the following is highest

Options

A. Atactic polyvinylchloride
B. Isotactic polyvinylchloride
C. Syndiotactic polyvinylchloride
D. All of these

Explanation

To determine which type of polyvinyl chloride (PVC) has the highest degree of crystallinity, we need to analyze the structures of atactic, isotactic, and syndiotactic PVC. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Types of PVC
- **Atactic Polyvinyl Chloride**: In this structure, the arrangement of the chlorine (Cl) atoms is random. This randomness leads to irregular packing, which does not favor crystallinity.

- **Isotactic Polyvinyl Chloride**: In isotactic PVC, all the chlorine atoms are arranged on the same side of the polymer chain. This uniformity allows for some degree of packing but is still not optimal for crystallinity.

- **Syndiotactic Polyvinyl Chloride**: In syndiotactic PVC, the chlorine atoms alternate sides along the polymer chain. This alternating arrangement allows for a more regular and closer packing of the polymer chains.

### Step 2: Analyze Crystallinity and Packing
- The degree of crystallinity in polymers is largely determined by how closely the polymer chains can pack together.
- **Atactic PVC**: Due to its random structure, it cannot pack closely, resulting in low crystallinity.
- **Isotactic PVC**: While it has a more organized structure than atactic PVC, it still does not achieve the highest packing efficiency.
- **Syndiotactic PVC**: The alternating arrangement of chlorine allows for the best packing among the three types, leading to the highest degree of crystallinity.

### Step 3: Conclusion
Based on the analysis of the structures and their packing capabilities, we conclude that **syndiotactic polyvinyl chloride has the highest degree of crystallinity**.

### Final Answer:
The type of polyvinyl chloride with the highest degree of crystallinity is **syndiotactic polyvinyl chloride**.

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