Research Progress on high performance basalt fiber
Recently, researchers from the environmental science and Technology Research Office of Xinjiang Institute of physical and chemical technology, Chinese Academy of sciences have made progress in the research of high performance basalt fiber. According to the characteristics of basalt fiber as an insulating material, the researchers prepared a functional sizing agent based on conductive nanocomposites, and optimized the sizing agent formula by full experimental method. On this basis, with basalt ore as raw material, combined with the process of coating sizing agent in the process of fiber preparation, the conductive basalt fiber was prepared in batch on the self built 50 hole wire drawing equipment in the laboratory.
Basalt fiber is a kind of filiform material made from natural basalt ore through crushing, melting, drawing and coating with sizing agent. Due to its good thermal stability, mechanical properties and corrosion resistance, these fibers are widely used in transportation, construction and marine fields. Basalt fiber itself is an insulating material, which does not have conductive properties. However, in the process of production and use, friction between fibers will produce static electricity, which affects the fiber clustering, processing and application convenience, and also limits its application in the field of high-performance materials.
The results show that the developed functional sizing agent has good dispersion stability and good electrical properties, and its conductivity is more than 200 μ s / cm; the micro morphology observation of the material shows that the sizing agent has good film-forming performance on the surface of basalt fiber, and the thickness is about 500 nm. The coating of the sizing agent makes the basalt fiber change from insulator to conductor in macroscopic, and the conductivity is more than 10% S / cm, which can meet the application of materials in the field of antistatic; compared with basalt fiber without wetting agent, the tensile strength of conductive basalt fiber is increased by 20%, and the relevant mechanism research shows that the wetting agent can effectively reduce the stress concentration on the surface of basalt fiber through crack passivation, bridging and other ways, and play a certain role in repairing the structural defects on the surface of basalt fiber. Relevant research results are published in materials today communications.
In addition, carbon nanotubes (CNTs) were directly grown on the surface of basalt fiber fabric by chemical vapor deposition (CVD) without additional catalyst, and the fiber material was used as reinforcing phase to effectively composite with polymer matrix to prepare polymer nanocomposites, and the electromagnetic shielding properties of the composites were studied. The results show that nano particles with the size of 10-100 nm precipitate on the surface of basalt fiber at high temperature, and the crystallinity of nano particles increases with the increase of treatment temperature. At high temperature, the precipitated nanoparticles can be used as catalysts to achieve in-situ controllable growth of carbon nanotubes. The direct growth of carbon nanotubes on basalt fiber fabric solves the problems of difficult dispersion and easy agglomeration of nanoparticles in polymer matrix, which provides a new method for efficient preparation of nanocomposites. The mechanism of electromagnetic shielding performance of nanocomposites is studied. It is found that the nano micron multilayer structure in the composite system improves the multiple reflection probability of electromagnetic wave in the material. The synergistic effect of electromagnetic wave absorption and multiple reflection generated by charge transfer, dipole polarization, capacitance double layer structure in the material makes the nanocomposites have better electrical shielding performance Magnetic shielding performance. The research results were published on carbon and selected as the cover of the 167th issue of the journal.
The related research achievements have applied for patents, and the research work has been supported by the cooperative research project of "light of the west" cross team and Key Laboratory of CAS, and the key cultivation direction of the 13th five year plan of CAS.
Traditional basalt fiber is endowed with multi-functional properties by nano composite technology
Source: Xinjiang Institute of physical and chemical technology, Chinese Academy of Sciences