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CN-121973513-A - Composite SMS non-woven fabric and preparation method thereof

CN121973513ACN 121973513 ACN121973513 ACN 121973513ACN-121973513-A

Abstract

The application discloses a composite SMS non-woven fabric and a preparation method thereof, and relates to the technical field of non-woven fabrics, wherein the composite SMS non-woven fabric comprises a bottom layer, a middle layer and a top layer; the bottom layer and the top layer are spun-bonded non-woven fabric layers, the middle layer is a melt-blown non-woven fabric layer, the bottom layer and the top layer comprise, by weight, 90-95 parts of polyester, 3-5 parts of polyethyleneimine and 1.5-5 parts of epoxy chain extender, and the middle layer comprises, by weight, 90-95 parts of polyester and 2-5 parts of additive. The application can improve the balance of longitudinal and transverse mechanical properties of the composite material by enhancing the interfacial binding force between the spun-bonded layer and the melt-blown layer.

Inventors

  • SUN WENQIANG
  • ZHAO QINGHUA
  • LIU KAIYU
  • WANG WENBO
  • DUAN XIAOQIN
  • LI XUELIAN

Assignees

  • 湖北拓盈新材料有限公司
  • 湖北联利非织造布技术创新中心有限公司

Dates

Publication Date
20260505
Application Date
20260317

Claims (10)

  1. 1. The composite SMS non-woven fabric is characterized by comprising a bottom layer, a middle layer and a top layer, wherein the bottom layer and the top layer are spun-bonded non-woven fabric layers, the middle layer is a melt-blown non-woven fabric layer, the bottom layer and the top layer comprise, by weight, 90-95 parts of polyester, 3-5 parts of polyethyleneimine and 1.5-5 parts of epoxy chain extender, and the middle layer comprises, by weight, 90-95 parts of polyester and 2-5 parts of additive.
  2. 2. The composite SMS nonwoven fabric of claim 1, wherein said epoxy-based chain extender is a styrene-glycidyl methacrylate copolymer.
  3. 3. The composite SMS nonwoven fabric according to claim 2, wherein the weight ratio of the polyethyleneimine and the styrene-glycidyl methacrylate copolymer is (1-3): 1.
  4. 4. The composite SMS nonwoven fabric of claim 1, wherein said polyethyleneimine has a weight average molecular weight of 10000-100000.
  5. 5. The composite SMS nonwoven fabric of claim 1, wherein the additive comprises an antimicrobial agent and an antistatic agent, the antimicrobial agent being nano silver particles and the antistatic agent being polyethylene glycol monostearate.
  6. 6. The composite SMS nonwoven fabric of claim 1, wherein said polyester is at least one of polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate ‌.
  7. 7. The composite SMS nonwoven fabric of claim 1, wherein the bottom layer has a grammage of 15-40g/m 2 , the top layer has a grammage of 10-30g/m 2 , and the middle layer nonwoven fabric has a grammage of 10-20g/m 2 .
  8. 8. A method for preparing the composite SMS nonwoven fabric according to any one of claims 1 to 7, comprising the steps of: s1, mixing polyester, polyethyleneimine and an epoxy chain extender, performing melt extrusion, spinning, drafting, lapping and spunbond forming to obtain a bottom layer, and obtaining a top layer by the same method as the bottom layer; S2, mixing polyester and an additive, and performing melt spraying and lapping to obtain an intermediate layer; And S3, sequentially lapping the bottom layer, the middle layer and the top layer from bottom to top, and hot-rolling to obtain the composite SMS non-woven fabric.
  9. 9. The method for preparing the composite SMS non-woven fabric according to claim 8, wherein in the step S3, an extrusion direction of the bottom layer forms an included angle of 10-80 degrees with a non-woven fabric lapping direction, an extrusion direction of the top layer forms an included angle of-10-80 degrees with the non-woven fabric lapping direction, and an extrusion direction of the middle layer forms an included angle of 90 degrees with the non-woven fabric lapping direction.
  10. 10. The method for preparing the composite SMS non-woven fabric according to claim 9, wherein an extrusion direction of the bottom layer forms an included angle of 10-45 degrees with a non-woven fabric lapping direction, and an extrusion direction of the top layer forms an included angle of-10-45 degrees with the non-woven fabric lapping direction.

Description

Composite SMS non-woven fabric and preparation method thereof Technical Field The application relates to the technical field of non-woven fabrics, in particular to a composite SMS non-woven fabric and a preparation method thereof. Background Nonwoven fabrics, also known as nonwovens, are sheet-like or web-like materials formed by orienting or randomly arranging fibers by mechanical, chemical or thermal bonding and the like, and are widely used in the fields of medical protection, sanitary articles, packaging materials, agricultural covers and the like. Compared with the traditional woven cloth, the non-woven cloth has the advantages of short production process, low cost, strong functional adjustability and the like, so that the non-woven cloth is rapidly developed in the industrial and civil fields. In the production of nonwoven fabrics, spunbonding and meltblowing are two common filament forming processes. The melt-blown method utilizes high-speed hot air flow to blow the melt into superfine fibers to form a melt-blown layer with finer fiber diameter and better filtering performance. SMS non-woven fabrics (namely spun-bonded-melt-blown-spun-bonded composite non-woven fabrics) formed by alternately compositing the spun-bonded layer and the melt-blown layer have the mechanical strength of the spun-bonded layer and the filtering performance of the melt-blown layer, and become important basic materials of medical protective materials (such as operating gowns, masks, protective clothing and the like). However, the conventional SMS non-woven fabric has the problem of obvious difference of transverse and longitudinal mechanical properties in the production process. The longitudinal direction is the direction of a production line, the fibers are highly oriented in the drawing and traction process, molecular chains are closely arranged along the longitudinal direction, so that the fibers have higher tensile strength, the transverse direction lacks effective external force drawing, the fibers mainly depend on natural diffusion and interweaving in the lapping process, and the orientation degree is low, so that the mechanical property of the fibers is far lower than that of the fibers in the longitudinal direction. The imbalance of the performance limits the use effect of the SMS non-woven fabric in application scenes with higher isotropy requirements. Aiming at the problems, the prior art is mainly focused on raw material modification or equipment structure optimization. For example, chinese patent application No. 202510859171.8 discloses a soft SMS nonwoven fabric, which improves softness and functionality of the material by introducing PP/PE copolymer, dopamine grafted hyperbranched polymer, and the like, and chinese patent application No. 201920423042.4 proposes a nonwoven fabric cross-lapping device, which aims to optimize a fiber lapping structure in a physical manner. However, the former is still not capable of effectively solving the problem of difference of mechanical properties in the transverse and longitudinal directions, while the latter is mainly suitable for the needling and hydroentangling process of short fibers, and is difficult to be directly applied to continuous molding of filament SMS non-woven fabrics. Therefore, how to maintain the balance of the transverse and longitudinal properties of the nonwoven fabric becomes a key problem in the current SMS nonwoven fabric technology development. Disclosure of Invention In order to improve the balance of the transverse and longitudinal mechanical properties of the non-woven fabric, the application provides a composite SMS non-woven fabric and a preparation method thereof. In a first aspect, the present application provides a composite SMS nonwoven fabric, which adopts the following technical scheme: the composite SMS non-woven fabric comprises a bottom layer, a middle layer and a top layer, wherein the bottom layer and the top layer are spun-bonded non-woven fabric layers, the middle layer is a melt-blown non-woven fabric layer, the bottom layer and the top layer comprise, by weight, 90-95 parts of polyester, 3-5 parts of polyethyleneimine and 1.5-5 parts of epoxy chain extender, and the middle layer comprises, by weight, 90-95 parts of polyester and 2-5 parts of additive. By adopting the technical scheme, the polyester is used as a main raw material, the high strength, the heat resistance and the good dimensional stability of the material are provided, the epoxy chain extender added in the bottom layer and the top layer can react with polyester molecular chains to improve the molecular weight and the melt strength of the polyester, so that the spun-bonded fiber is more uniform and has fewer defects in the forming process, the mechanical foundation of the fiber in all directions is improved from the material body, the polyethyleneimine is rich in amino groups, the interaction with the surface of the polyester fiber can be realized, the interfacial bindin