What do I use to make my own acrylic paint?

Hello Everyone,

I would like to make my own acrylic artist paint with my own pigments. I know where to get the pigments, but do not know what the "base" acrylic binder material would be called or where to get it? I would like to buy the base in bulk, very cheaply! - so I can make a lot of the paint.

Thank You
Astrid Green