Polymerisation of buta`-1,3`diene by free radical mechanism gives:

Options

A. trans`-1,4-polybutadiene
B. cis`-1,4-polybutadiene
C. polyvinyl polyethene
D. polyallyl polyethene

Answer

To solve the question regarding the polymerization of buta-1,3-diene by free radical mechanism, we can follow these steps:

### Step 1: Understanding the Structure of Buta-1,3-diene
Buta-1,3-diene has the following structure:
```
H2C=CH-CH=CH2
```
This structure consists of four carbon atoms with two double bonds between them.

### Step 2: Identifying the Polymerization Mechanism
The polymerization of buta-1,3-diene can occur through a free radical mechanism. This involves the formation of free radicals that initiate the polymerization process.

### Step 3: Considering the Reaction Conditions
The polymerization typically occurs under high temperature and pressure conditions, which facilitate the breaking of double bonds and the formation of new single bonds.

### Step 4: Identifying Possible Polymerization Centers
The polymerization can occur at different carbon centers:
- **C1 and C2**: This leads to the formation of polyvinyl polythene.
- **C1 and C4**: This can lead to two different forms based on the arrangement of the polymer:
- **Cis-1,4-polybutadiene**: When the polymerization occurs with a cis configuration.
- **Trans-1,4-polybutadiene**: When the polymerization occurs with a trans configuration.

### Step 5: Naming the Resulting Polymers
Based on the centers chosen for polymerization, the resulting polymers are:
- From C1 and C2: **Polyvinyl polythene**
- From C1 and C4 (cis): **Cis-1,4-polybutadiene**
- From C1 and C4 (trans): **Trans-1,4-polybutadiene**

### Step 6: Conclusion
The correct answers to the question about the polymerization of buta-1,3-diene by free radical mechanism are:
- Polyvinyl polythene
- Cis-1,4-polybutadiene
- Trans-1,4-polybutadiene

### Final Answer
The polymerization of buta-1,3-diene by free radical mechanism gives:
1. Polyvinyl polythene
2. Cis-1,4-polybutadiene
3. Trans-1,4-polybutadiene

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