A Quality, Cost Effective, Flammable HFC Blowing Agent Alternative for Construction Foam Applications: Blends of HFC-245fa and Hydrocarbons

摘要

Azeotropes have long been recognized as providing unique advantages as blowing agents. HFC-245fa forms an azeotrope over a wide range of concentrations with isopentane, cyclopentane, and/or n-pentane. The use of these blends allows the foam manufacturer to optimize k-factor and foam properties while minimizing costs. Although these HFC-245fa/hydrocarbon blends are flammable the foams co-blown with HFC-245fa have significant advantages over foams blown only with hydrocarbons. This paper compares the physical properties, environmental properties and polyol miscibility of azeotropic blends of HFC-245fa /hydrocarbon to the hydrocarbons, HFC-245fa, and HCFC-141b. In any alternative technology an additional concern will be what manufacturing and processing consideration must be taken into account. The paper will compare and contrast the azeotropic blends of HFC-245fa /hydrocarbon to the hydrocarbons, HFC-245fa, and HCFC-141b. Finally, the true test of any technology is the quality of the final product produced. If a product does not meet the needs of the consumer, it will obviously not be viable. The paper will conclude with a discussion comparing and contrasting the physical and performance properties of foams produced with the azeotropic blends of HFC-245fa /hydrocarbon vs. those blown with the hydrocarbons, HFC-245fa, or HCFC-141b. In order to provide a wide range of data, the test results will be reported on foam produced in the laboratory and at industrial scale trials as well as current commercially produced material. HFC-245fa/ hydrocarbon blend technology provides a wide range of alternatives to the industry. HFC-245fa blend foam technology produces a quality and cost effective alternative to HCFC-141b foams in the future.