Choose the correct statements from the following .

Options

A. Nylon 2-nylon 6 is a polyamide copolymer of alanine .
B. 3-Hydroxy pentanoic acid is a monomer of Nylon 2-nylon 6.
C. PHBV can never be used in the manufacture of orthopaedic devices.
D. None of these .

Answer

To solve the question, we need to evaluate each statement provided and determine whether it is correct or not. Let's analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** Nylon 2, nylon 6 is a polyamide copolymer of alanine.

- **Explanation:** Nylon 2, nylon 6 is actually a copolymer made from glycine (NH2CH2COOH) and amino caproic acid (which is a 6-carbon amino acid). Therefore, this statement is incorrect because it incorrectly identifies the monomers involved in the formation of nylon 2, nylon 6.

**Conclusion:** This statement is **not correct**.

### Step 2: Analyze the second statement
**Statement:** 3-hydroxy pantanoic acid is a monomer of nylon 2 nylon 6.

- **Explanation:** As established, nylon 2, nylon 6 is formed from glycine and amino caproic acid. 3-hydroxy pantanoic acid is not one of the monomers involved in the formation of nylon 2, nylon 6. Thus, this statement is also incorrect.

**Conclusion:** This statement is **not correct**.

### Step 3: Analyze the third statement
**Statement:** PHVB can never be used in the manufacture of orthopedic devices used in hip replacement surgeries.

- **Explanation:** PHVB (Poly-Beta-Hydroxy-Butyrate-Co-Beta-Hydroxy-Valerate) is known for its properties of stiffness (from 3-hydroxybutanoic acid) and flexibility (from 3-hydroxypantanoic acid). These properties make it suitable for use in orthopedic devices, including hip replacements. Therefore, this statement is incorrect as it states that PHVB cannot be used for such applications.

**Conclusion:** This statement is **not correct**.

### Step 4: Analyze the fourth statement
**Statement:** None of these statements are correct.

- **Explanation:** Since we have determined that all the previous statements (1, 2, and 3) are incorrect, this statement is indeed correct.

**Conclusion:** This statement is **correct**.

### Final Answer
The correct answer is: **None of these statements are correct.**

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