Stoffer, known nationally for his work in polymer and coatings chemistry, joined the faculty of the former Missouri School of Mines in 1963, after earning his Ph.D. degree from Purdue University. He directed the UMR Paint Short Course Program from 1985 to 1987, and was director of the Materials Research Center from 1992 to 2001. He became professor emeritus in 2000, but continued his research activities with graduate and post-doctorate students.
Stoffer's notable technical contributions to industry include pioneering work on microemulsion polymerization and the development of ultrasonic initiation of polymerization; corrosion-resistant coatings for aluminum; and an adhesion-measurement peel test for paint.