It can if the sealer is too thick. The elmer's should not create too much of a problem.
Also, try baking the molds in you kitchen oven at 150 degrees for about 1/2 hour. You'll be surprised how fast you can dry out a POP mold. I seal mine with epoxy and I can make a mold in the morning and have it dried, sealed and be pouring by the evening.
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