John Frederick Davis, 75, a chemical engineer who helped develop the lightweight plastic polypropylene, died Nov. 4 in Edmonds, Wash., of declining health caused by dementia.
Born in Wakefield, R.I., Davis graduated summa cum laude from the University of Rhode Island with a degree in chemical engineering and took graduate classes at Yale.
Davis worked for Shell Oil Co. for 33 years, playing a key role on a team that refined and developed applications for polypropylene.
The polymer has varied uses, including dishwasher-safe plastic food containers and fiber for the indoor-outdoor carpeting placed around swimming pools and on miniature golf courses.
After his retirement in 1986, Davis moved from Houston to Edmonds, a Seattle suburb.
He was a volunteer in a literacy program and a hospital pharmacy.