`{NH(CH_(2))_(6)NH-underset(O)underset(||)(C)-(CH_(2))_(4)-underset(O)underset(||)(C)}_(n)` is a

Options

A. Homopolymer
B. Copolymer
C. Additioin polymer
D. Thermosetting polymer

Answer

To determine the type of polymer represented by the structure `{NH(CH_(2))_(6)NH-underset(O)underset(||)(C)-(CH_(2))_(4)-underset(O)underset(||)(C)}_(n)`, we can follow these steps:

### Step 1: Identify the Monomer Units
The given structure can be broken down into two distinct monomeric units:
1. **Hexamethylenediamine**: This is represented by the part `NH(CH2)6NH2`, which contains two amine groups (-NH2) and a long carbon chain.
2. **Adipic Acid**: This is represented by the part `O=C(CH2)4C=O`, which contains two carboxylic acid groups (-COOH) and a carbon chain.

### Step 2: Determine the Type of Polymerization
The polymerization process that combines these two monomers involves the formation of amide bonds through the reaction of the amine groups from hexamethylenediamine with the carboxylic acid groups from adipic acid. This process results in the elimination of small molecules, such as water (H2O), which is characteristic of **condensation polymerization**.

### Step 3: Classify the Polymer
Now, we need to classify the type of polymer:
- **Homopolymer**: Made from one type of monomer. This is not the case here since we have two different monomers.
- **Copolymers**: Made from two or more different types of monomers. Since we have hexamethylenediamine and adipic acid, this polymer is a **copolymer**.
- **Addition Polymer**: Formed by the addition of monomers without the loss of any small molecules. This is not applicable here due to the condensation reaction.
- **Thermosetting Polymer**: These are polymers that become irreversibly hard upon heating. While this polymer may have thermosetting characteristics, the classification as a copolymer is more pertinent.

### Conclusion
The structure `{NH(CH_(2))_(6)NH-underset(O)underset(||)(C)-(CH_(2))_(4)-underset(O)underset(||)(C)}_(n)` is a **copolymer** formed through condensation polymerization.

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