Emerson Kampen, 67, who helped make Great Lakes Chemical Corp. the world's largest producer of specialty chemicals. Kampen joined the company in 1951 as a chemical engineer. He was named president in 1973, chief executive officer in 1977 and chairman in 1988. He was chairman emeritus at the time of his death. Great Lakes produces chemicals used in products such as fire extinguishers, swimming pool water treatments and petroleum additives. In West Lafayette, Ind., on Thursday of the complications of dermatomyositis, a disease of the connective tissue.