A process for spinning a bundled biaxial core-in-sheath auxetic yarn

Abstract

The application discloses a kind of bundled biaxial skin-core structure tensile yarn spinning processes, specifically including the following steps, step S1: one low modulus high elongation fiber filament one and one low modulus high elongation fiber filament two are unwound by active feeding roller, and are respectively fed into lower layer hollow spindle center tube one and lower layer hollow spindle center tube two, as two core filaments;Step S2: high modulus low elongation fiber filament one is wrapped on the surface of the core filament in positive helical line configuration at lower layer guide hook one;High modulus low elongation fiber filament two is wrapped on the surface of the core filament in reverse helical line configuration at lower layer guide hook two;Form biaxial skin-core structure covering yarn system, and pass through upper layer hollow spindle center tube;Step S3: at upper layer guide hook, the fiber filament yarn with excellent elastic elongation wound on upper layer hollow spindle is bound to the surface of the biaxial skin-core structure covering yarn system with low spiral covering density, to form bundled biaxial skin-core structure tensile yarn.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of covering yarn, and particularly relates to a bundling type biaxial core-sheath structure auxetic yarn spinning process. BACKGROUND

[0002] Composite yarn has appeared since the late 1950s, and provides greater space and more choices for the improvement and functionalization of yarn structure performance. However, it is basically still limited to the efforts on the reform of the material content of the multi-axial system, the spinning equipment and the optimization of the key process. Generally, when the traditional material is stretched, it shows a positive Poisson's ratio, that is, the material becomes narrow when stretched and becomes wide when compressed. The negative Poisson's ratio material expands when stretched or shrinks when compressed, and has more advantages than traditional materials in terms of shear bearing capacity, fracture resistance, energy absorption and the like, and thus has a wide application prospect in the fields of biomedical, protective equipment, national defense and the like. Therefore, from the perspective of the innovation of the multi-axial composite yarn structure regulation and optimization, the realization of the auxetic yarn with stable yarn structure characteristics and significant negative Poisson's ratio effect is a technical difficulty to be solved by the present application.

[0003] In recent years, the use of textile technology to prepare various negative Poisson's ratio materials has attracted more and more attention. As a kind of textile negative Poisson's ratio material, the development and application of negative Poisson's ratio yarn is also highly valued by people. For example, Hook's patent, patent application number US8002879 B2, Uses of Auxetic Fibres, relates to negative Poisson's ratio yarn, fabric, and lists some application fields. But the patent does not involve the specific spinning forming method of negative Poisson's ratio yarn. Hu Hong's patent, patent application number 201210212844.3, a kind of negative Poisson's ratio yarn structure and its manufacturing method, feeds the first yarn and the second yarn arranged alternately into the yarn forming area at the same time, and twists the first yarn and the second yarn fed at the same time by rotating the slot hole turntable, that is, the auxetic yarn structure is gathered into the entrance of the twisting and gathering device. The preparation method requires that the first yarn and the second yarn have the same number and are more than 2, since the yarn structure is mainly formed by twisting each component, in order to provide the forming structure of the yarn, the type of the yarn has a strong restriction, which limits the application range of the negative Poisson's ratio yarn to some extent. Yu Weidong's patent, patent application number 201710539903.0, negative Poisson's ratio composite spinning device, method and use of front pre-winding tube, based on a ring spinning machine, the short fiber sliver is output from the front roller nip and twisted into a high twist sliver; the rigid filament is fed through the feeder and wrapped around the high twist sliver through the pre-winding tube under a certain tension to form a negative Poisson's ratio yarn with the rigid filament slightly embedded in the high twist sliver. The preparation method needs to prepare a high twist sliver from a short fiber sliver, and needs to be equipped with a specific pre-winding tube and a more complex yarn forming process to realize the negative Poisson's ratio effect. The yarn is prone to have uneven twist and lack of structure stability under repeated stretching and excitation. And the limited degree of tensile deformation of the yarn leads to a smaller negative Poisson's ratio effect. Yu Weidong's patent, patent application number 201710539952.4, a three-axis system conical drum type composite spinning device and method of negative Poisson's ratio yarn, based on a ring spinning machine, the short fiber sliver and the certain tension elastic filament output synchronously from the front roller nip are gathered and twisted to form a two-axis system elastic yarn, which enters the cone and is fluffed and rounded and smoothed under the action of the inner wall of the cone which decreases from large to small; the rigid filament bundle is unwound through the unwinding device and wrapped around the cone at a set angle and relative position. Finally, the smooth and round elastic yarn output from the cone outlet is immediately wrapped by the wrapping yarn of the rigid filament bundle to form a three-axis system composite negative Poisson's ratio yarn. The yarn forming device is complex, and the setting track of each component yarn in the yarn forming process requires high precision control, and the preparation method needs to be further improved.

[0004] The present application aims to construct a bundled double-shaft core structure auxetic yarn, which is different from the above-mentioned patents in yarn forming principle, spinning mechanism, etc. How to reasonably configure the modulus of each component yarn and design and optimize the structure of the negative Poisson's ratio yarn is a technical difficulty that needs to be solved urgently. SUMMARY

[0005] The present application provides a kind of bundled biaxial core-sheath structure tensile yarn spinning process to solve the problems in the above background.

[0006] In order to achieve the above object, the technical scheme adopted by the present application is as follows: a kind of bundled biaxial core-sheath structure tensile yarn spinning process, specifically comprising the following steps,

[0007] Step S1: one low modulus high elongation fiber filament one and one low modulus high elongation fiber filament two are unwound by positive feeding roller, and are fed into the lower layer hollow spindle center tube one and the lower layer hollow spindle center tube two on the two sides of the hollow spindle package wrap spinning machine respectively, as two core filaments;

[0008] Step S2: the running direction of the lower layer hollow spindle one and the lower layer hollow spindle two is regulated, so that the high modulus low elongation fiber filament one wound on the lower layer hollow spindle one and the high modulus low elongation fiber filament two wound on the lower layer hollow spindle two are respectively unwound at the same speed in opposite directions; the low modulus high elongation fiber filament one and the high modulus low elongation fiber filament one are combined at the lower layer guide hook one with one core filament, and are wrapped on the surface of the core filament in positive helical line configuration; the low modulus high elongation fiber filament two and the high modulus low elongation fiber filament two are combined at the lower layer guide hook two with another core filament, and are wrapped on the surface of the core filament in reverse helical line configuration; a biaxial core-sheath structure wrapped yarn system is formed, and passes through the upper layer hollow spindle center tube;

[0009] Step S3: at the upper layer guide hook, the fiber filament yarn with excellent elastic elongation wound on the corresponding upper layer hollow spindle of the lower layer hollow spindle center tube three is bundled on the surface of the biaxial core-sheath structure wrapped yarn system at low helical wrapping density, to form a bundled biaxial core-sheath structure tensile yarn; through the synchronous winding of the winding roller on the collection yarn drum.

[0010] Preferably, in step S2, the high modulus low elongation fiber filament one in positive helical line configuration and the high modulus low elongation fiber filament two in reverse helical line configuration are controlled by a computer program controller through a servo motor to control the running direction and speed of the two belts one and two separately, to achieve the purpose of adjustable turning and variable frequency speed.

[0011] Preferably, in step S1, the low modulus high elongation fiber filament one and the low modulus high elongation fiber filament two are one of spandex filament, lycra filament, polyolefin-based elastic filament and rubber filament, and are thick in specification parameters.

[0012] Preferably, in step S2, the high modulus low elongation fiber filament one and the high modulus low elongation fiber filament two are one of metal wire, polyester filament, polypropylene filament, carbon fiber filament, glass fiber filament and basalt fiber filament, and are thin in specification parameters.

[0013] Preferably, the fiber filament yarn with excellent elastic elongation in the step S3 is one of acrylic, rubber thread, and composite yarn containing elastic thread, and is a fine specification parameter.

[0014] Preferably, by additionally arranging a pair of elastic thread positive feeding rollers below the hollow spindle wrap spinning machine, different pre-drafting multiples of low modulus and high elongation fiber filament one and low modulus and high elongation fiber filament two are realized by controlling the speed difference between the positive feeding roller and the winding roller; wherein, the pre-drafting multiple = 1 indicates that the filament is fed in a tensionless state; the pre-drafting multiple > 1 indicates that the filament is fed in a low tension state.

[0015] The beneficial effects of the above technical scheme are:

[0016] 1. The bundled biaxial core-sheath structure auxetic yarn spinning process of the application only needs to add positive feeding rollers below the existing hollow spindle wrap spinning machine, and implements innovation from the angles of spinning process and yarn structure precision control, so that a bundled biaxial core-sheath structure auxetic yarn can be successfully spun. The preparation process is simple and practical, easy to implement, easy to operate, and low in equipment modification cost, and can be continuously produced in batches, so it is easy to popularize and implement.

[0017] 2. The bundled biaxial core-sheath structure auxetic yarn spinning process of the application is formed by spinning process once, and the bundled structure gives the yarn good structural stability under repeated stretching stimulation. The technical difficulties such as surface yarn slippage, unstable structure and uneven twist distribution of the negative Poisson's ratio yarn structure in the prior art are overcome.

[0018] 3. The bundled biaxial core-sheath structure auxetic yarn spinning process of the application innovatively proposes the auxetic yarn forming and control mechanism, so that the auxetic yarn structure has a large negative Poisson's ratio and a stable auxetic effect, is suitable for the manufacture of different negative Poisson's ratio fabrics and structures, and has good application prospects in many fields such as functional clothing, composite material reinforcement manufacturing, and medical care. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is the spinning process principle diagram of the bundled biaxial core-sheath structure auxetic yarn of the application Figure 1 ;

[0020] Figure 2 is the spinning process principle diagram of the bundled biaxial core-sheath structure auxetic yarn of the application Figure 2 ;

[0021] Figure 3 is a structural change diagram of the auxetic yarn before and after bearing axial load;

[0022] Figure 4 is a schematic diagram of the structural change of the invented auxetic yarn before and after bearing axial load;

[0023] Figure 5 is a real picture of the auxetic yarn prepared according to the embodiment 1 of the invention before and after bearing axial load;

[0024] Figure 6 is a chart of selecting different spinning raw materials and different spinning process parameters of the embodiments 1-4;

[0025] wherein:

[0026] 1, low modulus high elongation fiber filament; 2, low modulus high elongation fiber filament; 3, positive feeding roller; 40, lower layer hollow spindle; 50, lower layer hollow spindle; 41, lower layer hollow spindle center tube; 51, lower layer hollow spindle center tube; 61, lower layer hollow spindle center tube; 7, high modulus low elongation fiber filament; 8, high modulus low elongation fiber filament; 9, lower layer guide hook; 10, lower layer guide hook; 11, biaxial core-sheath structure covering yarn system; 120, upper layer hollow spindle; 121, upper layer hollow spindle center tube; 13, fiber filament yarn with excellent elastic elongation; 14, upper layer guide hook; 15, bundled biaxial core-sheath structure auxetic yarn; 16, winding roller; 17, collection bobbin; 18, belt one; 19, belt two. DETAILED DESCRIPTION

[0027] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings, and the purpose is to help the technical personnel in the field to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present application, and to help its implementation.

[0028] As Figures 1 to 6 shown, the present application is a bundled biaxial core-sheath structure auxetic yarn spinning process, which has simple and practical preparation process, convenient implementation, easy operation, low equipment modification cost, can be continuously batch produced, and is convenient for popularization and implementation; the spinning process is formed at one time, the bundled configuration gives the yarn good structural stability under repeated stretching incentive; the present application innovatively proposes the forming and regulation mechanism of the auxetic yarn, so that the structure of the auxetic yarn has a large negative Poisson's ratio and a stable auxetic effect, and is suitable for the manufacture of different negative Poisson's ratio fabrics and structures.

[0029] Specifically, as Figures 1 to 6 shown, a bundled biaxial core-sheath structure auxetic yarn spinning process specifically includes the following steps,

[0030] Step S1: unwinding a low modulus high elongation fiber filament one 1 and a low modulus high elongation fiber filament two 2 by positive feeding roller 3, and feeding into the lower layer hollow spindle center tube one 41 and the lower layer hollow spindle center tube two 51 on both sides of the hollow spindle wrap spinning machine respectively as two core filaments;

[0031] Step S2: regulating the running direction of the lower layer hollow spindle one 40 and the lower layer hollow spindle two 50, so that the high modulus low elongation fiber filament one 7 wound on the lower layer hollow spindle one 40 and the high modulus low elongation fiber filament two 8 wound on the lower layer hollow spindle two 50 are respectively unwound at the same speed in opposite directions; the low modulus high elongation fiber filament one 1 and the high modulus low elongation fiber filament one 7 are combined at the lower layer guide hook one 9 with a core filament and wrapped on the surface of the core filament in a positive helical line configuration; the low modulus high elongation fiber filament two 2 and the high modulus low elongation fiber filament two 8 are combined at the lower layer guide hook two 10 with another core filament and wrapped on the surface of the core filament in an inverse helical line configuration; forming a biaxial core-sheath structure wrapped yarn system 11 and passing through the upper layer hollow spindle center tube 121;

[0032] Step S3: at the upper layer guide hook 14, the fiber filament yarn 13 with excellent elastic elongation wound on the corresponding upper layer hollow spindle 120 of the lower layer hollow spindle center tube three 61 is bundled on the surface of the biaxial core-sheath structure wrapped yarn system 11 at a low helical wrapping density, forming a bundled biaxial core-sheath structure auxetic yarn 15; and through the winding roller 16, it is synchronously wound on the collection bobbin 17.

[0033] The high modulus low elongation fiber filament one 7 in the step S2 in a positive helical line configuration and the high modulus low elongation fiber filament two 8 in an inverse helical line configuration are controlled by a computer program controller through a servo motor to separately control the running direction and speed of the two belts one 18 and the belts two 19, so as to achieve the purpose of adjustable turning and variable frequency speed.

[0034] The low modulus high elongation fiber filament one 1 and the low modulus high elongation fiber filament two 2 in the step S1 are one of spandex filament, lycra filament, polyolefin-based elastic filament and rubber filament, and have thick specification parameters.

[0035] The high modulus low elongation fiber filament one 7 and the high modulus low elongation fiber filament two 8 in the step S2 are one of metal wire, polyester filament, polypropylene filament, carbon fiber filament, glass fiber filament and basalt fiber filament, and have thin specification parameters.

[0036] The fiber filament yarn 13 with excellent elastic elongation in the step S3 is one of acrylic, rubber filament and composite yarn containing elastic filament, and has thin specification parameters.

[0037] By adding a pair of elastic fiber positive feeding roller 3 under the hollow spindle wrapping spinning machine, by adjusting the speed difference of the positive feeding roller 3 and the winding roller 16, the different pre-drafting multiples of the low modulus high elongation fiber filament one 1 and the low modulus high elongation fiber filament two 2 are realized. The pre-drafting multiple = 1 indicates that the filament is fed in a tension-free state; the pre-drafting multiple > 1 indicates that the filament is fed in a low tension state. The following specific examples are used to illustrate the specific working mode:

[0038] The following specific examples 1-4 are to select different spinning raw materials and different spinning process parameters according to the spinning process mentioned in the present application to make the bundled biaxial core-sheath structure auxetic yarn 15.

[0039] The yarn apparent diameter expansion rate calculation formula is: In the formula, d1 is the apparent diameter of the auxetic yarn after bearing axial tension (mm), and d0 is the apparent diameter of the auxetic yarn before tension (mm).

[0040] The evaluation criteria for the pros and cons of the negative Poisson's ratio effect of the auxetic yarn are as follows: the auxetic yarn obtained by the present application is divided into four grades according to the degree of the negative Poisson's ratio effect, i.e. "excellent (ε d ≥ 25%) ", "good (15% ≤ ε d < 25%) ", "medium (10% ≤ ε d < 15%) ", and "poor (ε d ≤ 10%) ".

[0041] Example 1:

[0042] Two low modulus high elongation spandex elastic fiber barrels, two high modulus low elongation polyester filament barrels, and one nitrile filament barrel with excellent elastic elongation are selected, and the bundled biaxial core-sheath structure auxetic yarn 15 is spun according to the above spinning process. The specific process parameters are shown in Table 1. Figure 6

[0043] Example 2:

[0044] Two low modulus high elongation lycra elastic fiber barrels, two high modulus low elongation glass fiber filament barrels, and one rubber filament barrel with excellent elastic elongation are selected, and the bundled biaxial core-sheath structure auxetic yarn 15 is spun according to the above spinning process. The specific process parameters are shown in Table 2. Figure 6

[0045] Example 3:

[0046] Two low modulus high elongation XLA elastic fiber barrels, two high modulus low elongation stainless steel barrels, and one cotton / spandex core-spun yarn barrel with excellent elastic elongation are selected, and the bundled biaxial core-sheath structure auxetic yarn 15 is spun according to the above spinning process. The specific process parameters are shown in Table 3. Figure 6 ​​​

[0047] Example 4:

[0048] Two low modulus high elongation rubber elastic filament tubes, two high modulus low elongation polypropylene filament tubes, and one spandex polyester covered filament tube with excellent elastic elongation were selected to spin the bundled biaxial core-sheath structure auxetic yarn 15 according to the above spinning process. The specific process parameters are shown in Table 1. Figure 6

[0049] The above describes the present application by way of example with reference to the accompanying drawings. It is clear that the specific implementation of the present application is not limited by the above method, as long as various non-essential improvements are made using the method concept and technical solution of the present application, or the above concept and technical solution of the present application is directly applied to other occasions without improvement, all of which are within the protection scope of the present application.​

Claims

1. A bundled biaxial core-in-sheath auxetic yarn spinning process characterized by: Specifically comprising the following steps, Step S1: unwinding a low modulus high elongation fiber filament one (1) and a low modulus high elongation fiber filament two (2) through the positive feeding roller (3), and feeding them into the lower layer hollow spindle center tube one 41 and the lower layer hollow spindle center tube two 51 on the two sides of the hollow spindle package wrapping spinning machine respectively as two core filaments; Step S2: regulating the running direction of the lower layer hollow spindle one 40 and the lower layer hollow spindle two 50, so that the high modulus low elongation fiber filament one (7) wound on the lower layer hollow spindle one 40 and the high modulus low elongation fiber filament two (8) wound on the lower layer hollow spindle two 50 are respectively unwound at the same speed in opposite directions; the low modulus high elongation fiber filament one (1) and the high modulus low elongation fiber filament one (7) are combined at the lower layer guide hook one (9) and wrapped on the surface of the core filament in a positive helical line configuration; the low modulus high elongation fiber filament two (2) and the high modulus low elongation fiber filament two (8) are combined at the lower layer guide hook two (10) and wrapped on the surface of the other core filament in an inverse helical line configuration; a biaxial core-sheath structure wrapped yarn system (11) is formed and passes through the upper layer hollow spindle center tube (121); Step S3: at the upper layer guide hook (14), the fiber filament yarn (13) with excellent elastic elongation wound on the corresponding upper layer hollow spindle (120) of the lower layer hollow spindle center tube three (61) is bundled on the surface of the biaxial core-sheath structure wrapped yarn system (11) at a low helical wrapping density to form a bundled biaxial core-sheath structure auxetic yarn (15); the fiber filament yarn (13) is synchronously wound on the collection bobbin (17) through the winding roller (16); The high modulus low elongation fiber filament one (7) in a positive helical line configuration and the high modulus low elongation fiber filament two (8) in an inverse helical line configuration in the step S2 are controlled by the computer program controller through the servo motor to separately control the running direction and speed of the belt one (18) and the belt two (19), so as to achieve the purpose of adjustable turning and variable frequency speed.

2. A bundled biaxial core-in-sheath structure auxetic yarn spinning process according to claim 1, characterized in that: The low modulus high elongation fiber filament one (1) and the low modulus high elongation fiber filament two (2) in the step S1 are one of spandex filament, lycra filament, polyolefin-based elastic filament and rubber filament, and have thick specification parameters.

3. A bundled biaxial core-in-sheath structure auxetic yarn spinning process according to claim 1, characterized in that: The high modulus low elongation fiber filament one (7) and the high modulus low elongation fiber filament two (8) in the step S2 are one of metal wire, polyester filament, polypropylene filament, carbon fiber filament, glass fiber filament and basalt fiber filament, and have thin specification parameters.

4. A bundled biaxial core-in-sheath structure auxetic yarn spinning process according to claim 1, characterized in that: The fiber filament yarn (13) with excellent elastic elongation in the step S3 is one of acrylic, rubber filament and composite yarn containing elastic filament, and has thin specification parameters.

5. A bundled biaxial core-in-sheath structure auxetic yarn spinning process according to claim 1, characterized in that: By additionally arranging a pair of elastic filament positive feeding rollers (3) below the hollow spindle package wrapping spinning machine, and by regulating the speed difference between the positive feeding roller (3) and the winding roller (16), the over-stable state equal feeding or under-feeding of the low modulus high elongation fiber filament one (1) and the low modulus high elongation fiber filament two (2) with different pre-drafting multiples is realized; wherein, the pre-drafting multiple = 1 indicates that the filament is fed in a tension-free state, and the pre-drafting multiple > 1 indicates that the filament is underfed in a low tension state.

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