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November 2, 2003-- Honeywell says it has developed a process to make polymer- nanoclay composites using organic swelling/ compatibilizing agents.

Such composites have much better properties than virgin polymers, but the production process is difficult because the components are not compatible, Honeywell says. The company says its agents help the mixing process and allow the production of composites of almost any thermoplastic in one step using conventional extrusion equipment. It is offering the technology for license via the yet2.com Web site.

The process uses a melt-compounding method that combines the nanoclay and the polymer using a compatibilizing agent, consisting of a mixture of organic radical substituted ammonium or phosphium cations. Honeywell says it has produced agents with specific bonding characteristics between a particular polymer and the clay platelet particles. These agents aid in the clay's exfoliation, resulting in less shear mixing, which, in turn, reduces polymer decomposition and molecular weight, the company says. Because less decomposition occurs, less waste is generated, it says.

"Virtually any product using thermoplastics would benefit from nanocomposites, including medical and electronic components, automotive parts, construction materials, machine parts, and food packaging," Honeywell says. "A key advantage is their substantially improved modulus at very low levels compared to conventional fillers, which require high loading," it says. This allows fabrication of lightweight parts with high stiffness, it adds. Polymer-nanoclay composites also have improved gas barrier properties, and have already been FDA approved for food and pharmaceutical packaging, Honeywell says.

Several firms are already commercializing polymer-nanoclay composites. Rockwood Specialties' unit Southern clay is working with General Motors (GM) and Basell on a composite that is being introduced in some GM models this year. American Colloids subsidiary Nanocor is working with several companies, including Honeywell, on barrier packaging and other applications. -ANDREW WOOD

* Supercritical Cyclohexane Process

Scientists from the National Institute of Advanced Industrial Science and Technology (Tokyo) say they have developed an efficient, low-cost process to produce cyclohexane and cyclohexanol from phenol in mild conditions using supercritical carbon dioxide as the solvent. The researchers say the process is much more environmentally friendly than conventional technologies that use organic solvents.

* Liquid to Solid at the Flick of a Switch

Researchers from Hong Kong University of Science and Technology say they have developed nanoparticle suspensions of urea-coated barium titanyl oxalate that become as hard as plastic under an applied electric field. The effect occurs because the particles polarize in the electric field and align into columns that are very hard to shear. The fluids have a yield stress high enough for practical applications in mechanical devices, say the scientists, who reported the work recently in Nature Materials.

* Nanodynamics' Cool-Running Fuel Cell

Nanodynamics (Buffalo, NY) says it has developed a processing technique that will allow a solid oxide fuel cell (SOFC) to produce electrical power at less that 550 C, well below the 800 C-1,000 C required by existing SOFC technologies. Specifics were not disclosed, however. The company says it expects to introduce a portable SOFC early next year that uses the technology.

* Solar Cells from Nanotube Hybrids

A group led by researchers from the University of Notre Dame (Grand Bend, IN) say they have developed a carbon nanotube- ferrocene hybrid that can function as a solar cell. If the material is irradiated with light, the ferrocene acts as an electron donor to the carbon nanotube, generating a current, say the scientists, who reported the work recently in the international edition of Angewandte Chemie.

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