The application in plastics utilizes the high strength,high flow and small size effects of ultrafine silica to improve the compactness,smoothness and wear resistance of plastic products.If properly modified by the surface,the purpose of simultaneously strengthening and toughening the plastic can be achieved.
The white carbon black is added to the polyethylene,and the ultrafine silica can be uniformly dispersed in the matrix by a special method to obtain a polyethylene composite material with high wear resistance and high hardness.The surface modification of silica was carried out by graft polymerization.The polymer macromolecular chain was used to effectively block the nanoparticles,reduce the degree of agglomeration,and then filled the polypropylene with it.The nanometer with excellent comprehensive properties was prepared by blending process.Si02/PP composite.At low additions,the toughness of polypropylene can be increased by about two times.If an appropriate amount of elastomer is added to the composite system,the polypropylene's anti-notch impact ability is improved by about 3 times while maintaining the rigidity and tensile strength of the polypropylene,and it is considered that the silica and the elastomer can synergistically achieve Enhance the purpose of toughening polypropylene.
Adding ultrafine silica to the nano-SiO 2/PMMA plastic prepared by PMMA by blending method can greatly improve the performance of the material.When the addition amount is 4%,the notched impact strength of PMMA can be increased by 80%or more,and the prepared composite material has excellent optical transparency.In plastics and other polymer blends.Silica can be added to improve the compatibility of the two phases.For example,adding styrene or methylchlorosilane-modified silica to the Ps and PP blends can reduce the interfacial interfacial tension,lower the cloud point temperature,and improve the compatibility of the two.
The addition of ultrafine silica to the epoxy resin can significantly improve the brittleness,and can overcome the defects of the rigidity and strength reduction of the toughness of the elastomer to achieve the purpose of strengthening and toughening.When the addition amount is 3 wt%,the impact strength of the composite system can be increased by 40%,and the tensile strength and the like can be increased by 21%.When the nano silica is modified by a coupling agent,the impact toughness can be improved by 124%,the tensile property can be improved by 30%,and the properties such as hardness,abrasion resistance,temperature resistance and insulation of the product can be improved.
