Which of the following is not semisynthetic polymer?

Options

A. cis polysioprene
B. Cellulose nitrate
C. Cellulose acetate
D. Vulcanised rubber

Explanation

To determine which of the given options is not a semi-synthetic polymer, we will analyze each option based on the definition of semi-synthetic polymers.

### Step-by-Step Solution:

1. **Understanding Semi-Synthetic Polymers**:
- A semi-synthetic polymer is derived from natural sources but has undergone some chemical modification. This means it is not purely natural nor entirely synthetic.

2. **Analyzing the Options**:
- **Option 1: Cis-polyisoprene**
- Cis-polyisoprene is the polymer form of natural rubber, which is obtained directly from the rubber tree. It does not undergo any chemical modification to create the polymer; hence, it is a natural polymer, not a semi-synthetic one.

- **Option 2: Cellulose Nitrate**
- Cellulose nitrate is derived from cellulose through a chemical modification process (nitration). Therefore, it is classified as a semi-synthetic polymer.

- **Option 3: Cellulose Acetate**
- Cellulose acetate is also derived from cellulose through acetylation, which is another form of chemical modification. Thus, it is a semi-synthetic polymer.

- **Option 4: Vulcanized Rubber**
- Vulcanized rubber is produced by chemically modifying natural rubber (cis-polyisoprene) to enhance its properties. This modification classifies it as a semi-synthetic polymer.

3. **Conclusion**:
- After analyzing all the options, we find that **Cis-polyisoprene (Option 1)** is the only one that is not a semi-synthetic polymer, as it is a natural polymer.

### Final Answer:
**Cis-polyisoprene (Option 1) is not a semi-synthetic polymer.**

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