reinforcing #plaster #materials (including #slaked-lime plaster) with hair, the traditional material, results in problems if you try wet-store it, because the alkaline plaster eats the hair, a problem that would be even worse with glass fiber. (I think this does not apply to calcium sulfate #gypsum plaster of paris.) Various cellulosic materials have been used, and those resist alkaline environments quite a bit better.
on 02015-08-15this lapsed Japanese patent from 2002 talks about making lime plaster (#slaked-lime) #materials sticky and #thixotropic by using 0.1%–5% #carrageenan (dry weight), which is apparently not as sticky as methylcellulose and won’t crack your plaster by absorbing water later. Some carrageenan molecules (κ and ι) gel with metal ions, while others don’t and are therefore more desirable for this. I'm surprised carrageenan will still gel in the insanely alkaline conditions found in lime plaster. It says you can use up to 4% or 5% (or sometimes as little as 2%) before it starts to shrink and crack as it dries. #patents
on 02015-08-15