Which of the following is a linear polymer?

Options

A. Low density polythene
B. High density polythene
C. Malamine
D. Amylopectin

Answer

To determine which of the following is a linear polymer, we need to analyze the options provided: low-density polyethylene, high-density polyethylene, melamine, and amylopectin.

### Step-by-Step Solution:

1. **Understanding Linear Polymers**:
- Linear polymers consist of long, straight chains of monomers. They have a simple structure without branching or cross-linking. This structure allows for strong intermolecular forces between the chains, resulting in higher density and strength.

2. **Analyzing the Options**:
- **Low-Density Polyethylene (LDPE)**: This polymer has a branched structure, which means it does not qualify as a linear polymer.
- **High-Density Polyethylene (HDPE)**: This polymer has a linear structure with minimal branching, making it a good candidate for a linear polymer.
- **Melamine**: This is a cross-linked polymer, which means it does not have a linear structure.
- **Amylopectin**: This is a branched polymer, as it has a complex structure with multiple branches.

3. **Conclusion**:
- Among the options provided, **high-density polyethylene (HDPE)** is the only linear polymer. It has long, straight chains that allow for strong intermolecular forces, which is characteristic of linear polymers.

### Final Answer:
The linear polymer among the given options is **high-density polyethylene (HDPE)**.