OM Group names Knowles president and COO

OM Group appoints David Knowles its president and chief operating officer

CLEVELAND (AP) -- Chemicals and materials maker OM Group Inc. said Thursday that it named David Knowles its president and chief operating officer.

Knowles' appointment is effective April 8. He most recently was executive vice president and chief operating officer of Myers Industries Inc. Before that he was president and CEO of Aristech Acrylics LLC, a specialty materials company.

Shares of Cleveland-based OM fell 6 cents to $24.74 in afternoon trading.