Unfortunately, when many do-it-yourselfers apply polyurethane over a water-based latex or acrylic paint, they end up with rampant flaking.
Quick Question - Polycrylic over Paint.
Water-based clear coats are easy to clean up, have low odor and the finish is much less likely to change over time.
Furthermore, a topcoat is scrubbable generally without damaging the paint itself. It looked very good and went from a fairly flat look to a glossy look and feel after only two coats. I don’t want to wax. Poly over Wax OR Wax over Poly? Polycrylic™ dries to the touch in 30 minutes and can be handled after 1 hour. The polycrylic is what yellowed it, but I put that on because the paint wasn’t enamel or meant for furniture specifically. A polyurethane finish can prolong the life of paint and prevent ultra violet rays from causing it to fade. For the painted portion, sand and prime, then paint. Instead, use Minwax® Fast-Drying Polyurethane or Minwax® Water Based Oil-Modified Polyurethane over any red mahogany stain.
Do You Need a Clear Coat Over Latex Paint? Once you’re done painting your wood piece, you might want to apply a finisher to protect it and make the paint last longer. The furniture turned out just how I wanted it. I’m not sure what you used, but just sharing what worked for me. I just used some Minwax water based polycrylic clear gloss from a rattle can over white latex paint (Behr paint and primer all-in-one) and had no yellowing at all. I was doing some reading on the interweb recently and came across a comment where someone made a 50-50 mix of acrylic latex paint and Minwax Polycrylic plus some Floetrol for spraying. FINISH APPEARS MILKY IN CAN BUT DRIES CRYSTAL CLEAR.
A polycrylic topcoat is more durable than paint alone, even paint with a sheen.
I often describe it as similar to coating a piece of furniture in a thin layer of hard plastic. I can’t quote what he/she said but, I believe, the main object was to make acrylic latex more sprayable and, secondarily, make it more durable and smoother.
I just finished applying an acrylic clear polyurethane clear coat gloss over a dresser that I had painted & glazed using latex paint & latex craft paints and a latex glaze. Polycrylic is a fantastic finisher to apply over painted furniture, especially lighter colored pieces.
You cannot paint over slightly tacky latex paint with a water based polycyclic finish. I’m surprised yours yellowed. The paint that I used under the polycrylic was a Behr latex paint. It has very little odour, is non-flammable, cleans up easily with soap and water, and can be recoated in only 2 hours.