Plastic Dissolving in Saltwater

It's transparent. It's durable. It vanishes in seawater.

TL;DR

Scientists in Japan have developed a plastic that dissolves in seawater.

It is what is known as a supramolecular material this material has strength and durability until it reacts with saltwater. Then it breaks down. Supramolecular materials don’t hold together in traditional ways, through electron sharing or covalent bonding, and this enables the saltwater dissolving. These plastics offer impressive versatility (non-toxic, non-flammable, and heat tolerance above 120°C) and are highly recyclable, with recovery rates of 82-91% of their component monomers.

We go more in depth after the paywall.