I have a few project ideas, and I thought of reusing the paper from various shop catalogs that I receive in my physical mailbox. I’d like to make it stiffer, something more like cardboard. I read somewhere online that you could use corn starch for this, mixed with water. Would it work? Do you have better ideas?
Depending on your use case, if you want something stiffer you could brush each sheet with slow curing epoxy resin, then layer and press it to create some DIY micarta (yes, micarta technically uses phenolic resin, but epoxy should work fine for most uses).