I have a player who wants to use gauntlets with his Brawler for enchanting purposes, and the race he chose grants him Powerful Build. By my understanding of the Brawler's Unarmed Strike ability text:
A brawler may attack with fists, elbows, knees, and feet. This means that a brawler may make unarmed strikes with her hands full.
…the answer would be a definite a negative. However I would like to see if anyone else has any other information, RAW or RAI (Rules as Interpreted), to assist in this matter.