I've been messing with making geopolymers with fly ash for a few years on and off now.
I'm betting that sodium silicate (water glass) COULD do the job, with a caustic soda activator.
One of my best was fly ash, wet to a plasticine consistency with sodium silicate solution (harvested from head gasket sealer), then an amount of caustic soda added, which dissolved in the goop, got hot, then set (literally) rock hard.
You can buy sodium silicate, not so easy down here, so I make it with silica gel and caustic soda as well.
I think with some messing you could get it to work.
There's some plastic type adhesives down here.http://www.pouron.com.au/faqs/