Perspex (used as a glass substitute) is made from which monomer? Identify the correct monomer for polymethyl methacrylate (PMMA).

Introduction / Context:
Perspex is a well-known trade name for polymethyl methacrylate (PMMA), a transparent thermoplastic valued for high optical clarity, weatherability, and lower density than glass. Recognising the correct monomer for PMMA is basic polymer chemistry knowledge useful in materials selection and processing.

Given Data / Assumptions:

• Perspex and Lucite are trade names for PMMA.
• We must match PMMA to its monomer.
• Distractor monomers correspond to other polymers (e.g., PET, PTFE, synthetic rubbers).

Concept / Approach:
PMMA results from addition polymerisation of methyl methacrylate (MMA). Each MMA unit adds across the carbon–carbon double bond forming the long PMMA chain. In contrast, DMT is a precursor for polyester (PET). Butadiene is a diene used for elastomers like polybutadiene or SBR. Tetrafluoroethylene is the monomer for PTFE (Teflon).

Step-by-Step Solution:
Map “Perspex” → PMMA.Identify PMMA monomer → methyl methacrylate (MMA).Eliminate DMT (for PET), butadiene (rubbers), tetrafluoroethylene (PTFE).

Verification / Alternative check:
Standard materials handbooks list PMMA as the polymer of methyl methacrylate, produced via bulk, solution, or suspension polymerisation routes.

Why Other Options Are Wrong:
DMT: used with ethylene glycol to make PET, not PMMA.Butadiene: elastomer precursor, not PMMA.Tetrafluoroethylene: gives PTFE, not PMMA.

Common Pitfalls:
Confusing trade names (Perspex/Lucite) and mixing them with polycarbonate (Lexan), which is a different polymer with different monomers and properties.

Final Answer:
Methyl methacrylate