Abstract: Polymer materials having viscosities ranging from about 50,000 up to above 1,000,000 centipoises are mixed with a gaseous foaming agent to provide a polymer/gas solution under pressure such that when the polymer/gas solution is subsequently dispensed at atmospheric pressure the gas is released from the solution and becomes entrapped in the polymeric material to form a homogeneous polymer foam. Mixing is accomplished by force feeding the gas and polymeric material into and through a low energy input disk mixer with a low pressure drop across the mixer such that premature foaming or reaction of the polymeric material is avoided. The disk mixer includes a tubular housing, one or more driven shafts extending along the length of the housing, and a series of disks spaced along the shafts. The foaming gas enters into solution in the polymer in the compartments between the rotating disks.

Abstract: A process for the recovery of solvent entrained in a water vapor laden exhaust gas stream exhausted from a spray painting system is disclosed. The process includes an oil absorption unit which absorbs and removes all but about 100 parts per million of the solvent from the exhaust gas stream while permitting air and water vapor to be vented from the system and a stripper which in turn removes all but about 0.001 mole fraction of any one solvent component trapped in the oil. The oil, which is substantially free of solvent, is returned to the absorption unit. The stripped solvent can then be condensed and reused by mixing it with the paint solids to be sprayed in the process; or, alternatively, it can be admitted as a vapor into the atmosphere surrounding a workpiece which is being coated in the spray painting system to raise the solvent humidity surrounding the workpiece to above about 70%.