Robert J. Fix, 76, of Allentown, died Feb. 7, 2021, in Lehigh Valley Hospital, Salisbury Township.

He and his wife, Mary J. (Achenbach) Fix, were married 53 years on July 15.

Born Jan. 16, 1945, in Allentown, he was the son of the late Robert A. and Hilda (Fischl) Fix.

An accomplished research chemist, he earned a Master’s degree in business administration from Kutztown University, and a Master’s degree of engineering in polymer science and a Master’s degree of science in chemistry, both from Lehigh University.

Working in research and development as a paint pigment chemist, he was employed at Kelly Scientific at Crayola, Easton.

Before that, he was employed at Silberline Mfg., Hometown, Elementis Pigment, Easton, Cookson Pigments, Newark, N.J., Mobay Chemical Corp., Patterson, N.J., Pope Chemical Co., Patterson, Heubach Chemical Co., Newark, and United Color, Newtown.

He wrote articles appearing in publications such as “Nature,” “Journal of the American Oil Chemists Society” and “Fourth International Congress on Surface Activity.”

He was a member of St. Francis of Assisi Roman Catholic Church, Allentown.

In addition to his wife, he is survived by children Robert W. Fix of Breinigsville, Raymond J. Fix (Stephanie) of Allentown, Linda F. Vidler of England, and Kathleen L. Fix (Jeremy Schaller) of Blandon; and grandchildren Mark, Scott, Emily, Samantha and Lucas.

He was predeceased by a son, David Edward Fix, who died in May 2020, and a daughter, Linda Marie Fix, who died in April 1969.

Due to COVID-19 concerns, a Memorial Mass of Christian Burial will be celebrated at a later date.

Expressions of sympathy may be made at heintzelmancares.com.

Contributions may be made to the church c/o the funeral home, P.O. Box 196, Schnecksville, PA 18078-0196.

Arrangements were made by Heintzelman Funeral Home Inc., Schnecksville.