Three-dimensional crimp fibre

Abstract

The invention provides a three-dimensional crimped fiber and consists of a first polymer component and a second polymer component. The second polymer is at least two discontinuous regions on the cross section of the fiber. At least two discontinuous regions of the second polymer are distributed in the first component or at least part of the two discontinuous regions is connected with the first component to form at least three separate regions. The regions formed by the first polymer component and the second polymer component respectively present an unsymmetrical mechanical structure. The technical proposal relieve the strict restrictions for the melt viscosity of the two components in the process of preparing the three-dimensional crimped composite fiber as well as the problem of the bend angle, and greatly widens the restrictions for the melt apparent viscosity difference and spinnability of the two components in the process of spinning the other sections. Simultaneously, the crimped property of the three-dimensional crimped composite fiber is equal to or better than the core-shift sheath-core fiber.

Description

technical field [0001] The invention relates to a three-dimensional crimped fiber, in particular to a three-dimensional crimped fiber with a controllable degree of crimp, which belongs to the technical field of composite fibers. Background technique [0002] There are many ways to manufacture single-component fibers and composite fibers (except for concentric sheath-core fibers) with a three-dimensional crimped structure, but they can be classified into two categories: [0003] One is to use high-temperature and high-pressure hot air to send it into the deformation nozzle or crimper for shaping after spinning to obtain a three-dimensional crimp effect. This method is a crimping method imposed on the fiber after the fiber is formed. Another method is to use different components or other asymmetric factors or conditions to create an internal structure with asymmetric factors during the fiber extrusion molding process, and to make the asymmetric factors appear in the post-proce...

AI Technical Summary

Problems solved by technology

[0006] Side-by-side composite fibers have good crimping properties, but in actual production applications, due to the differences in the melt index and apparent viscosity of the melt or solution between the two phases flowing side by side, often the composite spinning in the spinning process The fine flow will produce elbow angles on the surface of the spinneret, and the elbow angles will cause inhomogeneity in the cross-sectional structure and properties of the fibers during the spinning process, and even cause filaments to stain the surface of the spinneret plate, making spinning impossible. Therefore, in actual production, it is required to avoid or reduce the occurrence of this situation as much as possible

Reducing the apparent viscosity difference between the two components under the same conditions can reduce the adverse effects caused by the elbow angle. The elbow angle is always bent to the side of the component with high apparent viscosity, and the interface shape of the low viscosity component is always around For high-viscosity components, technicians will adjust the process temperature to reduce the elbow angle according to the direction of the elbow angle and the cross-sectional shape of the fiber in actual production, but the effect of doing so is often unsatisfactory

When the difference in apparent viscosities of the melts of the two components is too large or one of the components is too poor in spinnability, especially when spinning functional components with more powder Poor spinnability may make spinning impossible

[0007] Although the influence of the elbow angle on spinning eccentric sheath-core fibers is small, the degree of asymmetry of the fiber cross-section is usually smaller than that of side-by-side composite fibers, so under the same circumstances, the crimp performance of the obtained composite fibers is often not as good as side-by-side composite fiber

Moreover, sheath-core fibers require that the apparent viscosity of the sheath component is less than or equal to the apparent viscosity of the core component. When the apparent viscosity of the sheath component is much greater than the apparent viscosity of the core layer, the sheath-core section may not be formed.

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