Which polymer is light, strong and used for vacuum forming in schools and packaging?

• A. High Impact Polystyrene
• B. Acrylonitrile Butadiene Styrene
• C. Polyvinyl Chloride
• D. Nylon

Answer: (A)

High Impact Polystyrene is light and has good impact resistance without being heavy, plus it thermoforms very well. The polybutadiene modifier gives it toughness, so it can withstand handling in packaging while remaining easy to shape in a vacuum forming process. It heats to a temperature where it flows smoothly into a mold and then cools to a rigid, smooth part, which is ideal for classroom projects and packaging trays. Other polymers either cost more or have processing drawbacks: ABS is tougher but pricier; PVC can form, but heating can release fumes and edge quality isn't as good for simple vacuum forming; Nylon is strong but absorbs moisture and needs higher temperatures, making it less convenient for quick classroom use.