Plastics permanently take form and cannot regain their prior state

Evidence

This is why the group of synthetic materials that can be molded or modeled (bakelite, cellulose, nylon, polyamide, polyester, resin, silicone, etc.) and cannot regain their initial state after being fabricated are called ”plastics.” Many of them are rigid following formation and cooling. — Catherine Malabou, What Should We Do with Our Brain?, 287

Categorization

• DEFINE: Defines the everyday ‘plastics’ from which the conceptual plasticity metaphor draws — paves the ground for distinguishing true plasticity (giving and exploding form) from mere flexibility (adaptability).
• SHARE: For someone into materials science or etymology: the folk etymology bridge between polymer chemistry and brain-theory metaphors.