Plastics giant A. Schulman Inc, will be buying Citadel Plastics for $800 million. The move will expand product portfolio into specialty plastics as well as gain access to new industries.

Chicago-based Citadel, a portfolio company of private-equity firms HGGC and Charlesbank Capital Partners, engineers specialty thermoset composites, which are used in industries including transportation, electrical and health care. It had about $525 million in pro forma revenue last year and has more than 2,000 products.

“Their product offering not only enhances our existing portfolio, but presents attractive expansion opportunities in other fast-growing sectors such as aerospace, medical, LED lighting and oil and gas,” said Chief Executive Bernard Rzepka , who added the acquisition will help its portfolio become more highly specialized.

The deal is expected to add to earnings in the first 12 months of ownership, and could contribute as much as $25 million within 18 months, due mostly to sourcing and plant efficiency actions.

Acquisitions are a key strategy for the Ohio-based company. In the past five years, it has completed 10 acquisitions and three joint ventures, which contributed 30% of sales last year.

1. Schulman, which has a market capitalization of $1.2 billion, will fund the transaction with long-term debt and senior unsecured notes. The deal is expected to close before the end of the year.

Shares, inactive premarket, have increased about 4% this year through Friday’s close.