Which of the following are polyester polymers?

Options

A. Bakelite
B. Dacron
C. Glyptal resins
D. Nylon`5`

Answer

To determine which of the given options are polyester polymers, we will analyze each option based on the definition and characteristics of polyesters.

### Step-by-Step Solution:

1. **Understand the Definition of Polymers:**
- Polymers are materials made up of long and repeating chains of molecules. They can be classified into different categories based on their structure and properties.

2. **Identify Polyester Polymers:**
- Polyesters are a category of polymers that contain the ester functional group in their main chain. They are formed through the condensation reaction of diacids and diols.

3. **Examine the Options:**
- We have the following options to analyze:
1. Bakelite
2. Dacron
3. Glyptal resin
4. Nylon 5

4. **Analyze Each Option:**
- **Option 1: Bakelite**
- Bakelite is a thermosetting polymer, not a polyester. It is used for making electrical switches and handles. Therefore, this option is incorrect.

- **Option 2: Dacron**
- Dacron, also known as Terylene, is a polyester polymer formed from the polymerization of ethylene glycol and terephthalic acid. It is a thermoplastic polymer. Therefore, this option is correct.

- **Option 3: Glyptal Resin**
- Glyptal resin is synthesized from the condensation of ethylene glycol and phthalic acid, making it a polyester polymer. This is also a thermoplastic polymer. Therefore, this option is correct.

- **Option 4: Nylon 5**
- Nylon 5 is classified as a polyamide, which is a different category of polymers. It is a thermoplastic material but not a polyester. Therefore, this option is incorrect.

5. **Conclusion:**
- The correct polyester polymers from the options provided are Dacron and Glyptal resin.

### Final Answer:
- The polyester polymers from the given options are:
- **Dacron**
- **Glyptal resin**