Which material is 72% the heaviness of cellulose acetate and is known for its sturdiness and lightweight features?

The material that is 72% the heaviness of cellulose acetate and recognized for its sturdiness and lightweight characteristics is indeed polyamide. Polyamide, commonly known in the context of optics as nylon, is celebrated for its durable properties while maintaining a light weight.

Polyamides are synthetic polymers that can offer toughness and resistance to wear, making them suitable for applications in eyewear frames. They are often chosen for their ability to withstand impacts and their versatility in molding and shaping. The reduced density compared to cellulose acetate allows for comfortable wear without compromising the structural integrity necessary for optical products.

In contrast, while nylon is chemically related to polyamide and has similar properties, it is not as specific in the context of this question. Carbon filters and polystyrene do not exhibit the same combination of lightweight and durable qualities that polyamide offers, making them less applicable in the context of eyewear frame materials.