The fibre obtained by the condensation of hexamethylenediamine and adipic acid is :

Options

A. Nylon-6,6
B. Dacron
C. Taflon
D. Polyester

Explanation

To solve the question regarding the fiber obtained by the condensation of hexamethylenediamine and adipic acid, we can follow these steps:

### Step 1: Identify the Reactants
The reactants given in the question are hexamethylenediamine and adipic acid.
- **Hexamethylenediamine** has the formula: NH2(CH2)6NH2.
- **Adipic acid** has the formula: HOOC(CH2)4COOH.

### Step 2: Understand the Type of Reaction
The reaction between hexamethylenediamine and adipic acid is a condensation reaction, where two molecules combine with the elimination of a small molecule (usually water).

### Step 3: Write the Reaction
When hexamethylenediamine and adipic acid react, they form a polymer through the formation of amide linkages. The reaction can be represented as:
\[ \text{Hexamethylenediamine} + \text{Adipic acid} \rightarrow \text{Nylon 6,6} + \text{H}_2\text{O} \]

### Step 4: Identify the Polymer Formed
The polymer formed from this reaction is known as **Nylon 6,6**. This polymer is a type of polyamide, characterized by the presence of amide linkages (-CONH-) in its structure.

### Step 5: Confirm the Structure of Nylon 6,6
The repeating unit of Nylon 6,6 can be represented as:
\[ \text{-(NH-(CH2)6-NH-CO-(CH2)4-CO)-} \]
This structure indicates that it consists of 6 carbon atoms from hexamethylenediamine and 4 carbon atoms from adipic acid, totaling 12 carbon atoms, hence the name Nylon 6,6.

### Conclusion
Thus, the fiber obtained by the condensation of hexamethylenediamine and adipic acid is **Nylon 6,6**.

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