This plastic, PVA, is the one used in white glue, the one that kids use in school or carpenters use to glue things together. Wikipedia [0] says it biodegrades slowly. I believe (keyword: believe and am not sure) it could be redissolved in warm water, or might even be replaced by a renewable glue like gelatin.

[0] https://en.m.wikipedia.org/wiki/Polyvinyl_alcohol