How does vulcanization change the character of natural rubber ?

Explanation

### Step-by-Step Solution:

**Step 1: Understanding Natural Rubber**
Natural rubber is a polymer primarily composed of polyisoprene, which is a long chain of repeating units. It is known for its flexibility and elasticity but has limitations in terms of strength and resistance to environmental factors.

**Step 2: Introduction to Vulcanization**
Vulcanization is a chemical process that involves adding sulfur (and sometimes other chemicals) to natural rubber and heating it. This process creates cross-links between the polymer chains.

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