Lightweight filler for polyurethanes and composite materials →
Participant of the Exhibition of Polyurethanex 2018
In 2010 «STEP-Invest» company developed and implemented a production technology of Kerwood® lightweight filler, which is widely used in order to improve qualities of different materials. Lightweight and durable granules cardinally improve the quality of materials and bring a direct economic benefit. Next is a detailed description of it all.
The filler consists of light foamed ceramic microspheres with an integral and a finely porous structure beneath it, similar to a solid soap foam.
Meanwhile, a special form of cells provides high mechanical strength to the granules of the filler: it is, for different fractions from 0.6 to 12 MPa, when compressed in a cylinder following the Russian State Standard (GOST 9758 — 2012).
Usually seven different fractions with a particle size of 0.04 to 5 mm are produced.
Diatomite or trefoil formed of fossil remains of diatoms seaweed serves as raw material for the production of Kerwood® foamed ceramics. Diatomite consists of 65 — 90% of silicon oxide (SiО₂) and stable oxides (Al₂O₃, Fe₂O₃, etc.). That is why there are no organic materials in foamed ceramics making it completely safe and environmentally friendly.
Kerwood® foamed ceramics is extremely durable: its service life is at least 100 years, during this time the filler does not lose its qualities. Moisture resistance of the granules is very high: for various serial fractions, moisture absorption ranges from 4 to 7% by weight.
Kerwood® granules do not interact with any substances, do not burn or emit harmful for humans products into the atmosphere. In addition, they are not nutritious for bacteria and mold, do not attract rodents and insects and they are resistant to ultraviolet light.
In 2015, «NovTechKomponent» company began to use foamed ceramics, with polyurethane as a thickener and filler. The fine fraction of Kerwood® with the dimension of the granules is 0.1 — 0.3 mm. is four times lighter than sand, dry and clean (without including smaller granules) and is well suited for mixing with polyurethane.
The round form of foamed ceramics gives good fluidity, which significantly improves the occupancy rate of the form. It’s possible to significantly reduce weight of each product and obtain economic benefits using up to 30% of Kerwood® foamed ceramics in the manufacture of non-standard facade plat bands, slopes, frames, windows, doors, columns, ornaments, castings of decor and bas-reliefs.
The same success is obtained using foamed ceramics for production of sculptures. In the future, «NovTechKomponent» plans to start using foamed ceramics for painting pigments, manufacturing of facades of houses and furniture facades, production of plates for replacement in rubber boats, as well as sandwich panels.
According to the «NovTechKomponent» company’s technologists, Kerwood® products tend to be excellent fillers, thanks to combination of their qualities: high stability of physical parameters, low water permeability and chemical-biological stability.