We suck at recycling plastic. Even now, after all these years, we recycle less than 10% of the plastic worldwide, and we keep making more of it. Not only are we bad at recycling the plastic that can be recycled, but a big chunk of our plastic production is simply unrecyclable.
Researchers from the RIKEN Center for Emergent Matter Science In Japan may have found a solution.

A team led by Takuzo Aida developed a new kind of plastic that is strong, versatile, and biodegradable. Most importantly, it dissolves in seawater.

They created a polymer held together by reversible interactions called salt bridges. These cross-linked structures give the plastic its strength and flexibility, but they also have a unique vulnerability: salt water. When exposed to electrolytes found in seawater, the salt bridges destabilize, allowing the plastic to dissolve into its component molecules.

In ocean water, the new plastic starts to break down within hours. It gets even better: in soil, the sheets of plastic degrade in no more than 10 days and work to fertilize the soil.

The implications of this discovery are vast. Marine environments, often the final destination for plastic waste, could see a dramatic reduction in pollution.

Source: ZME Science

https://www.zmescience.com/research/materials/plastic-dissolves-seawater-microplastics/