Production method of conductive-toughening melt-blown composite nonwoven fabric

Abstract

The invention provides a production method of conductive-toughening melt-blown composite nonwoven fabric. The nonwoven fabric is produced by polymer chips, one-dimensional conductive nano filler and a dispersing agent. The production method specifically includes the steps of firstly, preparing conductive master batch; secondly, producing the conductive-toughening melt-blown composite nonwoven fabric. The production method has the advantages that the synergic effect of shear and collision during high-speed mixing and the dispersing agent is utilized, and extrusion by a double-screw extruder is used to allow the one-dimensional conductive nano filler to be evenly dispersed in the polymer; the traction effect of the high-speed hot air in a melt-blowing method to allow the one-dimensional conductive nano filler to oriented along the axial directions of fibers in the fibers and on the surfaces of the fibers, and the building of a conductive network is guaranteed while the conductivity threshold of the composite material is lowered evidently; the conductive-toughening melt-blown composite nonwoven fabric can effectively achieve the effect of structure-function modification integrated design of the composite material; the method is simple in step, convenient to operate and high in practicality.

Description

technical field [0001] The invention belongs to the technical field of non-woven fabrics and composite materials thereof, and in particular relates to a preparation method of a conductive-toughening melt-blown composite non-woven fabric. Background technique [0002] Carbon fiber reinforced resin matrix composites (CFRP) are widely used in the aerospace field because of their high specific strength, high specific modulus, light weight, corrosion resistance, and strong designability. This composite material usually uses a thermosetting resin as a matrix. The low toughness and electrical insulation of the thermosetting resin matrix make CFRP vulnerable to damage when subjected to lightning strikes or low-velocity impacts. [0003] For the conductive modification of CFRP, the current mainstream method at home and abroad is to use conductive micro-nano materials, generally including spherical micro-nano conductive particles, one-dimensional carbon nanotubes or metal nanowires, t...

AI Technical Summary

Problems solved by technology

However, this conductive modification process is relatively complicated, and the organic silver solution for non-woven fabrics will cause certain pollution and waste of resources, and the stability of this coating process on the surface of non-woven fabrics is difficult to control, and the additional cost The weight of the organic silver coating has an impact on the overall weight of the composite material, and the material cost is high

[0006] In the Chinese patent (a conductive fiber containing carbon nanotubes and its preparation method, CN 1226472 C), polyester, carbon nanotubes and coupling agent are mixed according to a certain mass ratio, extruded by a screw extruder and spun The conductive fiber is prepared by silk technology, which is characterized by the use of the excellent conductive properties of carbon nanotubes and the extremely high aspect ratio to prepare conductive fibers. At the same time, a special coupling agent can enhance the interaction between carbon nanotubes and polyester molecules. , but the stretching process used in this method has a small draw ratio for the fiber, resulting in random distribution of carbon nanotubes or a small degree of orientation inside the fiber, so this method is very useful for reducing the content of carbon nanotubes while forming a conductive The effect of the network is limited

More importantly, in the traditional chemical fiber production process, the draw ratio of the fiber in the drawing process is not enough to make the carbon nanotubes have sufficient orientation, so when the carbon nanotube content is low, it will be lower than that in the fiber. The conductive percolation threshold of CNTs is insufficient to form a conductive network

In addition, composite spinning must be extruded from different screw extruders for the raw materials of conductive masterbatch and polyester chips, and then ejected from different small holes with special-shaped cross-sections on the spinneret, while the conductive masterbatch The percentage content of the conductive filler must be higher than that of the final conductive fiber, especially when the content of the conductive filler is high, which may cause the spinneret hole of the conductive masterbatch raw material to be blocked, making it difficult to spin smoothly.

Images