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!) source

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!) source

$coolsciencegifs: Polymer absorbs water and expands. It keeps almost the same refractive$