Jim was born on July 11, 1934, in Easton in upstate New York and grew up on a farm there.

He was named a Fellow by the American Chemical Society in 2009 and has received a number of awards from the society to include the biennial Charles G. Overberger International Prize for Excellence in Polymer Research in 2013; the George S. Whitby Award for Distinguished Teaching and Research in 2009; Award in Polymer Chemistry in 2007 and 2008; Paul J. Flory Polymer Education Award in 2004; and the Award in Applied Polymer Science in 2002.

McGrath authored more than 400 publications and was involved with more than 40 patents to include optical devices formed from thermoplastic materials; method for making polyimide; highly conductive thermoplastic composites for rapid production of fuel cell bipolar plates; and chlorine resistant desalination membranes.