Sam Martin

OfficeMax said Thursday that executive VP and COO Sam Martin has left the company, effective July 21, to become CEO of another public company. OfficeMax has not said where Martin is going.Chairman and CEO Sam Duncan will assume Martin’s COO duties, effectively immediately, and said the office supplies retailer will not immediately seek a replacement for Martin.However, the company announced earlier this year that Duncan himself is slated to retire in February 2011, noting that it had begun the search for a new CEO.Martin was named COO of OfficeMax in 2007. Duncan credits him as having had an integral