Midland Silicones Memories

Abstract

One of the world’s most significant silicone manufacturing sites is in Barry, South Wales, owned by Dow Corning Corporation. Silicones have been produced at this site since 1952 but for the first two decades the companywas known asMidland Silicones Ltd. (not to be confused with the Midland Silicon Company L.L.C.). Midland Silicones was my entrance to the fascinating world of organosiliconmaterials and I hope that these indulgent reminiscences will trigger memories for some readers and acquaint others with this bygone joint venture. The two partners in the new company were Dow Corning Corporation of Midland, Michigan, USA and Albright and Wilson with headquarters at Oldbury in the West Midlands of England. Given these geographical realities one supposes that little time was devoted to deciding the name of the new company. To the American joint owners it was usually referred to as Midsil but to my colleagues at least, it was either Midland Silicones in full or shortened to MS, never Midsil. For the other partner, Albright and Wilson, the move into silicones was not particularly adventurous from an elemental viewpoint. Their operation was based on the chemistry of phosphorus. Silicon and phosphorus are adjacent members of the periodic table. Despite this elemental proximity Albright and Wilson’s contribution to the new venture was financial and managerial not technical. Much of the necessary capital came from the Oldbury firm as did the initial senior staff, including John Hughes, the head man at Barry throughout the Midland Silicones era. For several years such aspects as professional hiring were dealt with through the Albright and Wilson organization. Dow Corning with its almost ten years experience with silicones provided the technical knowledge and expertise as well as many materials and intermediates. The so-called Muller-Rochow direct process reaction lies at the heart of the silicone industry and the Dow Corning experience with this process was key to its establishment in Barry. It is still the standard technology for industrial preparation of organosilicon compounds, but even today there are few such primary reactors because of the complexity of the process and its high capital requirements. The process is based on the reaction of methyl chloride with silicon metal in a fluidized bed. Only Wacker Chemie AG and Midland Silicones Ltd. had this capability in Europe in the 1950s. The Barry site had originally been developed in the Second World War to extract magnesium from sea water. Given that the UK’s longest river, the Severn, and several other rivers make the Bristol Channel at Barry rather less salty than it is further west, this location decision does make one wonder. That venture was called Ocean Salts, a name that persisted for quite a few years among some local inhabitants after the establishment of Midland Silicones. I would like to think there are a few residents who still refer to the present site by the name I first knew it by although forty years on I realize this is rather unlikely. When I first saw the Barry site I was struck by its large concrete bowls. How clever, I thought; catchment basins for containing spilled silicone fluids in an emergency, little knowing I was looking at the settling bowls used in the old magnesium extraction process. The larger ponds behind the factory, possibly another remnant of Ocean Salts, were home to nesting swans and other wildlife. To Dow Corning’s credit, expansion at this site has not impaired this coexistence with Guest Editorial: Michael J. Owen