Flubber (material)

Flubber (named from the film The Absent-Minded Professor), Glorp, Glurch, or Slime are common names referring to a rubbery polymer formed by cross-linking of polyvinyl alcohol (PVA) with a boron compound. Flubber can be made from polyvinyl-acetate-based adhesives, such as Elmer's Glue, and borax as an elementary science education experiment.

The gelation process entails formation of a borate ester that crosslinks the chains of the PVA. Borate esters form readily by condensation of hydroxyl groups and the B-OH groups.

Flubber is a non-Newtonian fluid that flows under low stress, but breaks under higher stresses and pressures. This combination of fluid-like and solid-like properties makes it a Maxwell solid. Its behavior can also be described as being viscoplastic or gelatinous.

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