Michelman, Inc. has hired Dr. Martin A. Cohen as its new global director of commercial technology.      Dr. Cohen comes to Michelman with nearly 30 years of coatings research experience from his former positions at E.I DuPont de Nemours and Company, Kimberly-Clark, Lydall, Inc. and most recently as director of research and development for the performance coatings business of Noveon, Inc.      Dr. Cohen will be responsible for directing the research activities of Michelman’s performance addi...