Chemical producer Hercules Inc. said it will...

Chemical producer Hercules Inc. said it will sell its 38.5% stake in Himont Inc., the joint venture it formed in 1983 with Italy’s Montedison Spa, to the Milan company for $1.48 billion. Himont is the world’s largest producer of polypropylene, an oil-based plastic. Hercules also said it would buy back 15 million or nearly a fourth of its outstanding shares over the next two years. Hercules is based in Wilmington, Del.