The application of halloysite as a filler for modification of polypropylene. Part I. The characteristics of halloysite as a filler
Agnieszka Szczygielska, Jacek Kijeński
Quarterly No. 2, 2010 pages 181-185
DOI:
keywords: mineral clay, aluminosilicate, filler, halloysite
abstract Fillers being active components raging in size between 0,01 and 1 μm or passive measuring between 1 and 50 μm, present in a form of powder, fiber, cuttings or sheets are incorporated into different types of materials in order to lower the cost of production, improve the mechanical properties or give these materials certain characteristics such as: lowering flammability or improving electro insulation. Fillers should be chemically neutral in relation to matrix, so as not to influence the formation process. Moreover, they should have high dispersion (the size of molecules 5 to 10 micrometers), should not contain crystal and surface water and should also show good adhesiveness to the polymeric WARP. The above conditions are fulfilled in the case of mineral fillers such as: quartz, silica, dolomite or kaolin including mineral clays and halloysite. A review of present knowledge concerning the use of halloysite (HNT) as a filler in propylene (PP) modification has been done. A thorough characteristics of types of fillers has been performed with special emphasis on silicates and aluminosilicates. The synthesis of modified polymer composites is of crucial importance as it allows to obtain materials with specific properties suitable for the required application. Such modifications lead to improvement of mechanical properties. Based on literature data, HNT as a filler of polymeric composites was characterized, namely the structure of HNT, and selected parameters of HNT nanotubes. Halloysite is a mineral clay containing 44% silica, 38% aluminum oxide, 15% water and traces of metal oxides, including ferrous/iron oxide. HNT is already used as a sorption agent, insulation mat, coagulant, cosmetic clay, fertilizer and paint pigment.