【摘 要】
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BaSO4 nanoparticles as important functional materials have attracted considerable research interests,due to their X-rays barrier and absorption properties.Howev
【机 构】
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Beijing Advanced Innovation Center for Soft Matter Science and Engineering,State Key Laboratory of O
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BaSO4 nanoparticles as important functional materials have attracted considerable research interests,due to their X-rays barrier and absorption properties.However,most of BaSO4 nanoparticles prepared by traditional technology are nanopowders with broad size distribution and poor dispersibility,which may greatly limit their applications.To the best of our knowledge,the synthesis of transparent BaSO4 nanodispersions was rarely reported.Here,we firstly present a novel and efficient method to prepare transparent and stable BaSO4 nanodis-persions with a relatively small particle size around 10 to 17 nm using a precipitation method in a rotating packed bed(RPB),followed by a modification treatment using stearic acid.Compared with the BaSO4 prepared in a traditional stirred tank,the product prepared using an RPB has much smaller particle size and narrower size distribu-tion.More importantly,by using RPB,the reaction time can be significantly decreased from 20 min to 18 s.Furthermore,the transparent BaSO4-polyvinyl butyral nanocomposite films with good X-ray shielding perfor-mance can be easily fabricated.We believe that the stable BaSO4 nanodispersions may have a wide range of applications for transparent composite materials and coatings with X-ray shielding performance for future research.
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