Nanotubular chrysotile fillers for radiation and protective constructional composites

Strengthening of manifestation of quantum-dimensional effect in nanoparticles will make considerable impact on absorption of photon radiation. Therefore, application of ultradisperse systems will promote high-quality strengthening of radiation protective properties of material and will allow creation of more compact material with improved protective characteristics. The unique combination of properties of chrysotile allows creation of the materials on its basis which possess high mechanical and thermal strength, radiation resistance. The presence of the combined water in its structure favours appearance of radiation protective properties by neutron radiation in such materials. In this connection the authors offered to fill chrysotile nanotubes with nanodispersed compounds that make it possible to raise its radiation protective characteristics. As a result, these compounds have to possess higher extinction coefficient of y-radiation, and respectively possess high density and content of heavy elements. Nanocrystal plumbous tungstate of PbWO4 is offered to use as compound for intercalation. The authors developed a method to produce nanotubular filler of radiation protective composite materials by filling hydrosilicate nanotubes of chrysotile structure with refractory slightly soluble compound on the basis of PbWO4 and serial processing of material with solutions of reagents. The best result has been achieved when chrysotile was treated consistently in K2WO4 and Pb(СН3СОО)2 solutions, at the same time mass content of PbWO4 in an end product reaches 30%. The introduced K2WO4 filled nanotubes not only in the internal channel, but also in interlayered space, and localization of PbWO4 happens both in internal channels of nanotubes and on their surface. In spite of the fact that the developed technology does not allow us to modify chrysotile so that all injected PbWO4 could be contained only in internal canals of nanotubes, the obtained product gets the improved radiation protective characteristics keeping other performance properties of chrysotile.