Which polymer can be used for making contact lenses for eyes

Options

A. Polymethylmethacrylate
B. Polyethelene
C. Polyethylacrylate
D. Nylon - 6

Answer

To determine which polymer can be used for making contact lenses for eyes, we will analyze the options provided and the characteristics of each polymer in relation to contact lens applications.

### Step-by-Step Solution:

1. **Identify the Types of Contact Lenses**:
- There are two main types of contact lenses: hard lenses and soft lenses.
- Hard contact lenses were the first type developed, while soft contact lenses are more commonly used today.

2. **Consider the Requirements for Contact Lens Materials**:
- The materials used for contact lenses must be biocompatible (non-toxic), allow oxygen permeability, and have the ability to mix with the water in our eyes.

3. **Evaluate the Given Options**:
- **Option 1: Polymethyl Methacrylate (PMMA)**:
- PMMA is a clear, hard plastic that was widely used for hard contact lenses due to its optical clarity and stability.
- **Option 2: Polyethylene**:
- Polyethylene is a flexible plastic but does not have the necessary optical properties or oxygen permeability for contact lenses.
- **Option 3: Polyethylacrylate**:
- Polyethylacrylate is a polymer that can be used in some applications, but it is not the primary choice for contact lenses.
- **Option 4: Nylon 6**:
- Nylon 6 is a strong synthetic polymer but is not suitable for contact lenses due to its rigidity and lack of oxygen permeability.

4. **Conclusion**:
- Based on the analysis, the most suitable polymer for making hard contact lenses is **Polymethyl Methacrylate (PMMA)**. It has been historically used for this purpose due to its favorable properties.

### Final Answer:
The polymer that can be used for making contact lenses for eyes is **Polymethyl Methacrylate (PMMA)**.

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