What is a good clear paint sealer for latex paint that won't turn yellow like polyurethane?

I've painted the floor (plywood) with latex paint and added some flowers along the border. I want to put a sealer on it that won't turn yellow like polyurethane does. Any ideas? This is a covered porch so it needs to withstand the weather that may blow in on it. Thanks for your help!!What is a good clear paint sealer for latex paint that won't turn yellow like polyurethane?
Minwax has a water based version of their Helmsman spar urethane. it's a clear, non-yellowing finish for interior or exterior use.What is a good clear paint sealer for latex paint that won't turn yellow like polyurethane?
Varithane makes a water based polyurethane that doesn't yellow. It is for floors. The only problem is that it is for interior floors. I don't know how it will hold up to the weather outside.
There are non-yellowing products - varnish, you need to put several coats on, let dry well between each coat
there is a exterior water base poly by zar, It will do the job