Concrete casting: acrylic sheets inside styrofoam box to reuse form
Traditional wood forms intended to be reused are oiled so the concrete doesn't stick.  There are many ways to do what you want, breakdown wood forms, plastic, whatever. Not much will stick to concrete if the forms are removed when the concrete is cured just enough to stay together.  Make sure the insides of your forms have draft angles built in so they can be removed without tearing out some concrete and lube the forms well.  This can be done but you'll have to experiment a bit.

One thing absolutely to keep in mind is concrete is very heavy, a 4 ft x 4 ft sidewalk slab weighs about 700 lbs, so the biggest concern is making the forms strong enough to not collapse.  Foam foundation forms are extensively cross tied so they don't blow out and are made from strong foam. A thin acrylic sheet without good bracing will bow severely.  Based on one of my messy mistakes, marginal forms explode right when you have them just about full!