The development of a non-fluorocarbon-based extruded polystyrene foam which contains a halogen-free blowing agent

This technology is concerned with a new type of extruded Polystyrene foam (XPS), which gives high performance of thermal insulation without containing any fluorocarbons as a blowing agent. Avoiding such typically harmful materials will help solve global environmental problems like ozone layer depletion and global warming. Kaneka Corporation developed this technology for the first time in the world. As a blowing agent of this new XPS in place of fluorocarbons we adopted isobutane, an excellent green gas that helps prevent ozone layer depletion and global warming. However, there is a problem: it is difficult to Secure high performance of thermal insulation and flame retardation when isobutane is used. This originates from the fact that isobutane has a higher thermal conductivity than fluorocarbons, and is highly flammable. To overcome the former problem, we found a novel cell structure to secure high performance of thermal insulation, and we developed new technologies to control it. To solve the latter problem, namely securing flame retardation, we clarified the mechanism to Suppress combustion of isobutane, and developed a new flame retardation technology by the addition of specific compounds. As a result of a combination of these technologies, we were able to develop and commercialize a new XPS with high performance of thermal insulation. These technologies directly contribute to prevent adverse effects on the global environment such as ozone layer depletion and global warming, by not using fluorocarbons. And, in addition, these technologies indirectly but more greatly contribute to global warming prevention by the reduction in carbon dioxide emissions through a high effect of energy conservation as a thermal insulator. Therefore, the thermal insulator with these technologies is valuable for environmental protection. And as the needs for a material for better energy conservation will increase. the contribution of this technology will expand much more in the future.