Hollow glass microspheres are used in coatings or composites and exhibit unusual mechanical and heat-insulation properties. In many countries, heat insulation by means of coatings is achieved by adding hollow or solid glass microspheres in acrylic-based coatings. Many coatings are developed with high absorbtivity in the visible regime and very low emissivity in the IR regime for architectural as well as industrial coatings.
Issues like stringent environmental regulations, customer requirements and competitive markets can be tackled with innovative raw material usage and developing new processes. There are many raw materials available that can be called ‘answers awaiting questions’; a good example being microspheres.
These specialty materials are used for many purposes in many diverse industries. Microspheres are innovative raw materials in the coatings industry, and are diverse because both solid and hollow formats are readily available. Solid spheres are most commonly used in reflective traffic paints where the microspheres are used as light reflectors. Hollow glass microspheres are small, spherical particles ranging in size from 12-300 microns in diameter, and wall thickness up to 0.1 micron. As these microspheres are hollow, the true density is very low, ranging from 0.60 g/cc to as low as 0.025 g/cc. Organic hollow glass microspheres are mostly composed of polystyrene, polyacrylonitrile or phenolic materials, while inorganic microspheres are glass, ceramic or made from fly ash from thermal power plants.
This article comes from pcimag edit released