But no good deed goes unpunished, and Mr. Feuerstein’s rebuilding efforts left Malden Mills saddled with debt, even as Polartec sales soared in the late 1990s. In 2001 the company went into bankruptcy; it emerged, two years later, with a restructuring plan that stripped Mr. Feuerstein of his management roles. His attempt to buy the company back was rejected by the new board, and he left in 2004.
“I was one of the few fighting to keep employment here. It really was a very difficult and losing fight,” he told The Globe in 2015. “I became one of the victims in the end.”
Aaron Mordechai Feuerstein was born on Dec. 11, 1925, in Boston. His grandfather, Henry Feuerstein, had founded Malden Mills in 1907, and his father, Samuel, had later taken it over. His mother, Miriam (Landau) Feuerstein, was a homemaker.
His first wife, Merika, died in 1984, and his second wife, Louise, died in 2013. He is survived by his children, Daniel, Raphael and Joyce; his sister, Juliet Korngold; and six grandchildren.
He attended Boston Latin School and Yeshiva University, where he studied English and philosophy. He joined Malden Mills immediately after graduating in 1947. The company, which made upholstery and other textiles before developing Polartec, moved to the Lawrence plant in the 1950s.
Mr. Feuerstein’s father founded the Young Israel synagogue in Brookline, Mass., where his family lived. Just over a year before the fire at Malden Mills, an electrical short at the synagogue started a fire that destroyed much of the building. Mr. Feuerstein donated $1 million to rebuild it.
Malden Mills did not survive long after Mr. Feuerstein left. The new owners moved Polartec production to New Hampshire and Tennessee in the late 2000s, and in December 2015 — on the eve of the 20th anniversary of the fire — announced that the factory would close at the end of the year.
Today the building houses several small businesses, including a brewery, a hydroponic farm and a 3-D printing facility.