Synthesis and Foaming of Water Containing Activated Carbon-Nano/Microparticulate Polystyrene
T2008-125 A novel method to increase thermal efficiency infrared absorption and bulk density of polystyrene foams.
Blowing agents create a cellular structure from a liquid plastic resin and, in certain cases, function as an insulating component of the foam. Hydrogen-containing chlorofluorocarbons and fluorocarbons are common blowing agents in the foam industry for extrusion forming of Polystyrene foam. However, it is known that these blowing agents cause ozone-depletion. Currently, hydrocarbons and carbon-dioxide are the most appealing alternatives, but it is difficult to produce foams from these compounds. It is critical to develop environmentally-friendly and inexpensive blowing agents that produce quality foams.
Researchers at The Ohio State University, led by Dr. L. James Lee, have developed foam extrusion process that uses water as a co-blowing agent for CO2 to control the bulk density, bubble size, and expansion ratio. The method prepares water expandable polystyrene (PS)-activated carbon (AC). AC pre-saturated with water is introduced to the styrene monomer, which forms water-in-oil inverse emulsion. Spherical water/AC PS beads are obtained through suspension polymerization. By extrusion foaming process, a PS/AC composite foam with ultra-low density is produced.
- Thermal Insulation
- Fire-Retardant Materials
- Energy Recovery
- Scaffolds for cell attachment and growth
- Produces foams with ultra-low bulk density
- Foams produced by this method have greater thermal insulation efficiency and infrared absorption
- Expandable PS/AC beads prevent quick escape of water during early stage of extrusion foaming process