What is the function of `S` in the vulcanization of rubber ?

Explanation

### Step-by-Step Solution:

1. **Understanding Vulcanization**:
- Vulcanization is a chemical process that improves the physical properties of natural rubber. It involves heating rubber with sulfur at a specific temperature range (373 to 415 Kelvin).

2. **Composition of Vulcanized Rubber**:
- The process involves mixing raw natural rubber with sulfur. The resulting product is known as vulcanized rubber.

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