All major concrete chemical manufacturers produce a form of
breathable non-yellowing sealer. I don't know why you want the
breathable. I don't really know why you want a sealer. The tree
poop doesn't care if it is sealed or not, it is going to fall just
fine. The sealer may make it easier to remove, but then it will
need to be reapplied. I am not aware of anything that will stop
the tree leavings.
Here is one:
here is a lot of technical information:
Silanes and siloxanes make good sealers, but they are not
Keep the whole world singing . . .
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