Air Products and Chemicals, Inc.

Joseph G Santangelo

James J Weber

Richard G Sinclair

Daniel P Kramer

Lloyd Mahlon Robeson

Jeffrey A Kuphal

Richard D Tenaglia

Edward F Elton

John M Fernbacher

Andrew J Patrylak

Christian J Lambertsen

A process for producing cellular foamed articles from high temperature engineering polymers wherein polymeric blowing agents are utilized to expand the polymers. The process comprises mixing a first polymer capable of being foamed with a second polymer comprising at least one poly(alkylene carbonate) to provide a polymer blend; heating the polymer blend to a temperature sufficient to melt the polymer to be foamed and to decompose the second polymer to form gas inclusions within the first polymer; expanding the melted first polymer containing the gas inclusions to form a foamed article; and cooling the foamed article to a temperature below the melting or softening point of the foamed article. Polymers which may be foamed according to the process include those polymers which can tolerate processing temperatures in excess of 260.degree. C. Suitable poly(alkylene carbonate) foaming agents include poly(propylene carbonate), blends of two or more poly(alkylene carbonates) and copolymers and terpolymers formed by polymerizing two or more oxirane compounds in the presence of carbon dioxide.

Method for foaming high temperature polymers using poly(alkylene

The present invention relates to a binder and a method for making and shaping a green body of ceramic powder and subsequently producing a formed ceramic body. The method of the present invention comprises admixing a ceramic powder with a binder comprising a polyalkylene carbonate to form a ceramic-binder mixture. The binder of the present invention comprises a polyalkylene carbonate, preferably polyethylene carbonate or polypropylene carbonate.

CO.sub.2 copolymer binder for forming ceramic bodies and a shaping

CO.sub.2 copolymer ceramic-binder composition

A process for safely preventing, controlling and/or extinguishing fires in confined spaces without damage to equipment, loss of habitability for personnel, loss of consciousness for personnel or a significant impact on the mental acuity of personnel in the confined space, which comprises introducing carbon dioxide and another inert gas, e.g. nitrogen or helium, to the confined space to lower the oxygen content to a concentration in the range between 8% and 15% by volume while increasing the carbon dioxide content of the confined space to an amount in the range of 2% to 5% by volume. The combination of reducing oxygen concentration and increasing carbon dioxide concentration in the gaseous environment of the confined space works together to sustain mammalian life, in particular, maintaining consciousness and mental acuity while not supporting, i.e. extinguishing, flame.

Breathable fire extinguishing gas mixtures

The present invention is a novel class of block copolymers and a process of making the same. An alkylene oxide is reacted with CO.sub.2 in an organic solvent in the presence of an organometallic catalyst to form a polyalkylene carbonate. A second alkylene oxide is subsequently added without the addition of catalyst. The resulting product is a block copolymer comprising distinct, covalently linked, alkylene carbonate blocks.

Process for producing novel block alkylene polycarbonate copolymers

Metal castings having reduced residual carbon ash and surface flaws are produced by an evaporative pattern casting process, in which an organic foam pattern is vaporized upon contact with a molten metal leaving a metal replica of the pattern. The organic foam used in this process comprises a polymer formed by polymerizing CO.sub.2 with one or more oxirane compounds.

Method for producing metal castings

In an injection well for underground gasification of carbonaceous materials, either liquids or solids, by partial combustion with oxygen-rich gas in the presence of a moderating fluid such as steam, air, CO.sub.2 or the like, in which the moderating fluid is introduced through an annular path surrounding the injection tube through which the oxygen-rich gas is injected, back flow of gasification products from the well is prevented by providing a flow restriction in the annular path to increase the linear flow velocity of the moderating fluid while maintaining the designed mass flow rate of said moderating fluid. The flow restriction is so designed that at the predetermined downward flow rate of said moderating fluid the critical velocity of the moderating fluid at the restriction corresponds to the formula:

In situ coal gasification

High recovery of useful energy from the heat of reaction in the oxidation of black liquor is obtained by integrating the oxidation into the multiple effect evaporation system of the pulp mill recovery sequence. The heat of reaction is thereby recovered as flash steam, which when combined with the vapors from an appropriate evaporator body enables recovery of its energy through further evaporation. The oxidation reaction may be carried out on the liquor leaving the second effect of the evaporation sequence for maximum energy recovery, or in accordance with an alternative embodiment, the reaction is carried out between the first effect and the flash tank with preferable addition of a second flash tank in series with the first.

Growing community of inventors

Allentown, PA, United States of America

Joseph G Santangelo