They're made of soft polymer that will stay comfortable all day. (geekwrapped.com)
Can lignin integrate into soft polymer matrices? (sciencedaily.com)
His actuators are made from soft polymer materials called elastomers, and his first prototype, a six - fingered gripper, resembles a starfish: when air is pumped into it through a thin tube, air sacs within expand, causing its digits to contract in a gentle grasping motion. (newscientist.com)