deathpoolquinn:coolsciencegifs:Polymer absorbs water and expands. It keeps almost the same refractiv
deathpoolquinn:coolsciencegifs:Polymer absorbs water and expands. It keeps almost the same refractive properties as water and appears invisible.The polymer is Sodium Polyacrylate (thank you, thecraftychemist!)sourcecan I just -- source link