Polyacrylate family check: which polymer below does NOT belong to the polyacrylate (acrylic ester/methacrylate) class?

Introduction / Context:
“Acrylics” often refer to acrylate and methacrylate esters (e.g., PMMA, polyethyl acrylate). Polyacrylonitrile (PAN) is an acrylic fibre precursor but chemically distinct, containing nitrile groups rather than ester functions typical of polyacrylates.

Given Data / Assumptions:

• PMMA and polyethyl acrylate are classic acrylics (methacrylate and acrylate esters).
• PAN is formed from acrylonitrile and exhibits different reactivity and properties.

Concept / Approach:
Polyacrylates are ester-containing polymers derived from acrylic/methacrylic acid esters. PAN, while sometimes grouped under “acrylics” in textile terminology, is not a polyacrylate chemically; it belongs to the nitrile family with distinct solubility, thermal behaviour, and carbon-fibre precursor utility.

Step-by-Step Solution:
Classify each option by functional group.Identify PAN as nitrile-based, not an acrylate ester.Conclude PAN does not belong to the polyacrylate class.

Verification / Alternative check:
Polymer classifications separate acrylate esters (adhesives, coatings) from PAN (fibre precursor, barrier properties).

Why Other Options Are Wrong:
PMMA and polyethyl acrylate are canonical acrylics.

Common Pitfalls:
Equating textile term “acrylic fibre” with chemical class “polyacrylate.”

Final Answer:
Polyacrylonitrile