Linear polymer among the following is

Options

A. Melamine
B. Starch
C. Bakelite
D. Polyvinylchloride

Answer

To determine the linear polymer among the given options, we need to analyze the structure of each polymer mentioned: melamine, starch, bakelite, and polyvinyl chloride (PVC).

### Step-by-Step Solution:

1. **Identify the Structures of Each Polymer:**
- **Melamine:** Melamine is a cross-linked polymer. It has a network structure formed by the cross-linking of melamine molecules through hydrogen bonds. This structure is not linear.
- **Starch:** Starch is a polysaccharide made up of glucose units. It exists in two forms: amylose (which is linear) and amylopectin (which is branched). Since starch contains both linear and branched components, it cannot be classified as purely linear.
- **Bakelite:** Bakelite is also a cross-linked polymer. It has a three-dimensional network structure, which makes it non-linear.
- **Polyvinyl Chloride (PVC):** PVC is a linear polymer. Its structure consists of repeating units of vinyl chloride, which are arranged in a straight chain without cross-linking.

2. **Conclusion:**
- Among the options provided, **polyvinyl chloride (PVC)** is the only linear polymer.

### Final Answer:
The linear polymer among the following is **polyvinyl chloride (PVC)**.

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