A sound-absorbing material of polyurethane composite air layer structure fabric and preparation method thereof

Abstract

The present invention provides a sound-absorbing material comprising a polyurethane composite air layer structure fabric and a preparation method thereof. The sound-absorbing material of the present invention is formed in one step on a conventional weaving machine, and has the characteristics of high production efficiency and a wide range of applications. The sound-absorbing material of the present invention comprises a four-layer fabric structure, wherein the four layers of fabric are formed into three layers of air layer woven fabric in the weft direction. The non-air layer portion of the air layer woven fabric is produced by orthogonally joining warp and weft yarns. The proportion of the air layer in the fabric can be adjusted by adjusting the amount of weft yarn used in the plain weave and orthogonal weave. After the air layer fabric is shaped with a circular stick, a polyurethane material is coated on the upper and lower air layer portions of the fabric to form a sound-absorbing material comprising a polyurethane composite air layer structure fabric. The sound-absorbing material of the present invention has uniform porosity and roughness, and when combined with polyurethane, it has a sound absorption effect that combines porous sound absorption with resonant sound absorption, and exhibits excellent broadband sound absorption at low, medium, and high frequencies.

Description

Technical Field

[0001] The invention relates to the field of fabric weaving, in particular to a sound-absorbing material of a polyurethane composite air layer structure fabric and a preparation method thereof. Background Art

[0002] With the development of textile weaving technology, research on the application of industrial textiles in sound insulation and noise reduction has become increasingly widespread. The sound absorption frequency of general textile materials is limited to the medium and high frequency bands, and the sound absorption coefficient is not very good, which limits the scope of use of textile sound-absorbing materials. Ordinary single-layer textiles have poor sound absorption performance. Increasing the thickness of the fabric or increasing the number of fabric layers can improve the sound absorption performance to a certain extent, but the improvement in sound absorption effect in the medium and low frequency bands is still insufficient. Rubber and polyurethane, as materials based on the vibration sound absorption principle, have good sound absorption effects in the low frequency bands, but very poor sound absorption effects in the medium and high frequency bands. Current research on the sound absorption performance of polyurethane, rubber and textile composites has not combined the excellent sound absorption properties of both due to the limitations of the composite method. For example, patent number CN 110534083A uses spacer fabric, hollow microspheres, and polyurethane materials to prepare a three-phase composite structure sound-absorbing material. Its average coefficient is around 0.3, which shows that the sound absorption performance is not good. For example, patent number CN 116121931A describes a composite hollow fiber fabric sound-absorbing material with excellent sound absorption performance in the 2000-3000 Hz frequency range, with an average sound absorption coefficient of 0.55. This performance is lower than 0.35 in other frequency ranges. This demonstrates that hollow fabrics alone cannot achieve broadband sound absorption. Therefore, it is imperative to find a stable sound-absorbing structure and material that can absorb sound across nearly the entire frequency range. Summary of the Invention

[0003] In response to the above problems, the present invention proposes a sound-absorbing material of a polyurethane composite air layer structure fabric and a preparation method thereof. The air layer woven fabric with indirect weft tubes is heat-treated after the fabric is formed to form a stable woven air layer structure. Polyurethane is then compounded at specific parts of the air layer fabric to achieve a new type of structural composite sound-absorbing material that is stable and has a wide-band excellent sound absorption effect in low, medium and high frequencies.

[0004] The present invention adopts the following technical solutions:

[0005] A method for preparing a sound-absorbing material of a polyurethane composite air layer structure fabric comprises an upper fabric layer, a middle upper fabric layer, a middle lower fabric layer, and a lower fabric layer, which are sequentially arranged from top to bottom; adjacent fabric layers are connected by a connecting structure at even intervals, and single-layer portions and double-layer connecting portions are alternately arranged to form a row of diamond-shaped tubular air layers, forming a total of three rows of air layers; after heat-setting the fabric, polyurethane material is coated on the inner wall of the middle row of air layer fabrics to form the sound-absorbing material of the polyurethane composite air layer structure fabric.

[0006] Furthermore, the warp yarn ratio and weft yarn ratio of the upper fabric, the middle upper fabric, the middle lower fabric and the lower fabric are all 1:1:1:1, the adjacent fabric layers are connected by orthogonal bonding to form an air layer, and the weft ratio of the double-layer connecting part and the single-layer part of the fabric is 2m:n, where m and n are any positive integers.

[0007] Furthermore, each layer of fabric is woven on a common loom using 8 heald frames. The fabric is woven using a straight threading method, with the warp yarns being threaded in the order of 1, 2, 3, 4, 5, 6, 7, and 8 as a cycle.

[0008] Furthermore, the diamond-shaped tubular air layer is formed by the weft-direction tube-forming of the fabric, the warp and weft yarns of the single-layer part of the fabric are independently interwoven, and the double-layer connecting part is formed by interweaving the warp and weft yarns by orthogonal knotting of the non-tube-forming part of the fabric.

[0009] Furthermore, each layer of fabric is woven from polyurethane thermoplastic fiber material, and during heat setting, the connection between two adjacent layers of fabric is subjected to a heat treatment at 150-180° C. for 10-15 minutes.

[0010] Further, the polyurethane material is 450-500g / m 2 After coating on the middle and upper fabrics and the middle and lower fabrics, the coating is dried at 80°C for one hour.

[0011] A sound-absorbing material of polyurethane composite air layer structure fabric is prepared by the above method.

[0012] After adopting the above technical solution, the present invention has the following advantages compared with the prior art:

[0013] The sound-absorbing material obtained by the present invention is formed in one step on an ordinary weaving machine, and has the characteristics of high production efficiency and a wide range of product applications. The sound-absorbing material obtained by the present invention is composed of an air layer woven fabric with indirect weft tubes. After the fabric is formed, it is heat-treated to form a stable woven air layer structure. The proportion of the air layer in the fabric can be adjusted by adjusting the weft yarn amount used in the plain weave and the orthogonal knot weave. Then, polyurethane is compounded in specific parts of the air layer fabric to achieve a stable sound absorption effect with excellent broadband in low-medium frequency, medium frequency, and high frequency. The sound-absorbing material of the polyurethane composite air layer structure fabric of the present invention not only takes into account the softness of the textile material, but also gives the fiber fabric material a better sound absorption effect, and at the same time greatly broadens the application of textile sound-absorbing materials, such as providing a production method for practical products such as sound-absorbing curtains.

[0014] The present invention is described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0016] Figure 2 This is an interwoven diagram of the fabric yarn structure of the present invention.

[0017] In the accompanying drawings, the meanings of the components represented by the reference numerals are listed as follows:

[0018] 1. Upper layer of fabric; 2. Upper middle layer of fabric coated with polyurethane; 3. Lower middle layer of fabric coated with polyurethane; 4. Lower layer of fabric; S1. Yarn structure of plain weave air layer; S2. Yarn structure of non-air layer; DETAILED DESCRIPTION

[0019] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0020] like Figure 1-2 A polyurethane composite air layer structure fabric sound-absorbing material is shown. The fabric is a woven fabric with several types of warp and weft yarns interwoven to form a hollow weft portion. The fabric comprises, from top to bottom, an upper fabric layer 1, a middle upper fabric layer 2, a middle lower fabric layer 3, and a lower fabric layer 4. The air layer fabric structure S2 accounts for 30% to 90% of the overall fabric. The air layer fabric has a height of 9 to 10 mm. The air layer fabric has independent hollow structures with its surface and inner layers, allowing for a four-layer fabric to be formed in one go.

[0021] The main steps of preparing the sound-absorbing material of the polyurethane composite air layer structure fabric of the present invention and the preparation method thereof are as follows:

[0022] (1) Analyze the distribution and arrangement of the yarn structure according to the fabric shape, design the yarn structure interweaving diagram of the air layer woven fabric and draw the organization diagram;

[0023] (2) Designing the aperture size of the air layer of the air layer woven fabric according to the morphological structure of the air layer woven fabric;

[0024] (3) Carry out the preparation work such as drawing in the heddle and reed according to the drawing of the air layer woven fabric;

[0025] (4) The warp yarns are drawn in the order of 1, 2, 3, 4, 5, 6, 7, and 8 as a cycle. The warp yarns are drawn in the reeds of the appropriate size according to the target warp yarn density.

[0026] (5) The air layer woven fabric of the present invention is formed by weft arching, the air layer fabric portion and the upper and lower connecting parts of the fabric are organized, and the two parts are alternately transformed. The formation principle is that the warp and weft yarns are interwoven according to the directional design. The formation of the fabric is mainly completed by steps 1 to 4.

[0027] (6) It should be noted that the "air layer" fabric described in the present invention refers to a fabric that is hollow in the middle, but the pore height of the fabric air layer needs further heat setting treatment to maintain the pore height. The air layer fabric of the present invention uses a heat treatment of 10-15 minutes and 150-180 ° C to form a stable air layer structure.

[0028] Example 1

[0029] Embodiment 1 of the present invention provides a sound-absorbing material of a polyurethane composite air layer structure fabric and a preparation method thereof, wherein the air layer woven fabric is interwoven with polyester yarns.

[0030] The preparation steps of air layer woven fabric are as follows:

[0031] (1) According to the structural design of the air layer woven fabric, the SGA598 semi-automatic prototype was selected as the weaving equipment for Example 1. Two strands of 40 / 2 polyester yarn were used as the warp yarn of the fabric and were drawn into the heddle in a cycle of 1, 2, 3, 4, 5, 6, 7, and 8 until 250 cycles were completed.

[0032] (2) Take the warp yarn after drawing into the reed and insert it into the No. 80 steel reed in the manner of 4 into one reed. After the reeding is completed, warping is performed to make the warp tension uniform.

[0033] (3) After the organization diagram is converted into a pattern pattern and stored in the program of the small prototype machine, weaving is started, and 40 / 2 polyester yarn is introduced into the weft insertion of the weaving opening to alternately weave the obtained air layer woven fabric. The fabric warp density of the air layer woven fabric is 320-340 yarns / 10cm, and the fabric weft density is 160-180 yarns / 10cm.

[0034] (4) A wooden stick with a diameter of 10 mm was inserted into the hollow part of the prepared air layer woven fabric, and then placed in an oven at 150°C for 10 minutes for air layer setting heat treatment. The average height of the hollow of the heat-treated fabric was maintained at 9-10 mm.

[0035] (5) The shaped fabric is coated with polyurethane material at a density of 450-500 g / m 2 After coating on the middle and upper fabrics and the middle and lower fabrics, the coating is dried at 80°C for one hour.

[0036] Sound absorption performance test of polyurethane composite air layer structure fabric: The sound absorption performance of the polyurethane composite air layer structure fabric was tested according to the national standard GBT18696.2-2002 "Measurement of sound absorption coefficient and acoustic impedance in acoustic impedance tubes Part 2 Transfer function method".

[0037] Example 1 Fabric Acoustic Performance Test Description Table

[0038]

[0039] The sound absorption performance of the prepared polyurethane composite air layer structure fabric is greatly improved compared with the sound absorption performance of the non-heat-setting fabric. From the acoustic performance test description table of the fabric in Example 1, it can be concluded that after the sound wave frequency of 1000 Hz, the average sound absorption coefficient of the polyurethane composite air layer structure fabric is increased by 134% compared with the sound absorption coefficient of the non-heat-setting fabric. Compared with the air layer fabric after heat setting, its sound absorption performance is biased towards low-frequency movement, and the sound absorption effect is more significantly improved in the sound absorption frequency range of 500 Hz-3000 Hz. From the acoustic performance test description table of the fabric in Example 1, it can be concluded that the sound absorption coefficient of the four-layer hollow structure woven fabric after polyurethane coating on specific parts is increased by 45.01% in the low and medium frequency range of 500-1000 Hz, 76.29% in the medium frequency range of 1000-2000 Hz, and 30.9% in the medium frequency range of 2000-3000 Hz. Although the sound absorption coefficient of the composite material decreases after the polyurethane material is coated on the middle and upper layer fabrics and the middle and lower layer fabrics in the high frequency band of 3000-5000 Hz, the overall sound absorption effect in its frequency range still maintains a relatively good level.

[0040] The foregoing is an example of the best mode of carrying out the present invention. Any portion not described in detail herein is common knowledge within the skill of one of ordinary skill in the art. The scope of protection of the present invention is determined by the claims. Any equivalent transformation based on the technical teachings of the present invention is also within the scope of protection of the present invention.

Claims

1. A method for preparing a sound-absorbing material of a polyurethane composite air layer structure fabric, characterized in that: The invention comprises an upper fabric (1), a middle upper fabric (2), a middle lower fabric (3) and a lower fabric (4) arranged in sequence from top to bottom; two adjacent fabric layers are connected by a connecting structure at even intervals, and the single-layer part and the double-layer connecting part are arranged alternately to form a row of diamond-shaped tubular air layers, forming a total of three rows of air layers; after the fabric is heat-set, a polyurethane material is coated on the inner wall of the middle row of air layer fabrics to form a sound-absorbing material of a polyurethane composite air layer structure fabric; The diamond-shaped tubular air layer is formed by the weft-direction tubes of the fabric. The warp and weft yarns of the single-layer part of the fabric are independently interwoven, and the double-layer connecting part is formed by interweaving the warp and weft yarns by orthogonal knotting in the non-tube-direction part of the fabric; each layer of fabric is woven with polyester thermoplastic fiber material.

2. The method for preparing a sound-absorbing material of a polyurethane composite air layer structure fabric according to claim 1, characterized in that: The warp yarn ratio and weft yarn ratio of the upper fabric (1), the middle upper fabric (2), the middle lower fabric (3) and the lower fabric (4) are all 1:1:1:1, adjacent fabric layers are connected by orthogonal bonding to form an air layer, and the weft ratio of the double-layer connection part and the single-layer part of the fabric is 2m:n, wherein m and n are any positive integers.

3. The method for preparing a sound-absorbing material of a polyurethane composite air layer structure fabric according to claim 1, characterized in that: Each layer of fabric is woven on an ordinary loom using 8 heald frames. The fabric is woven using the straight threading method, and the warp yarns are drawn in the order of 1, 2, 3, 4, 5, 6, 7, and 8 as a cycle.

4. The method for preparing a sound-absorbing material of a polyurethane composite air layer structure fabric according to claim 1, characterized in that: During heat setting, the joints of two adjacent layers of fabric are heat treated at 150-180°C for 10-15 minutes.

5. The method for preparing a sound-absorbing material of a polyurethane composite air layer structure fabric according to claim 1, characterized in that: The polyurethane material is coated on the middle and upper fabrics and the middle and lower fabrics at a density of 450-500 g / m 2 , and then dried at 80° C. for one hour.

6. A sound-absorbing material of polyurethane composite air layer structure fabric, characterized in that: Prepared by the method according to any one of claims 1 to 5.

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