Self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber and preparation method thereof

Abstract

The present invention provides a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber and a preparation method thereof. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has a skin-core structure, wherein the core layer of the skin-core structure is polyetheretherketone and the skin layer is polyphenylene sulfone. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber of the present invention is a composite fiber having a skin-core structure, and the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and excellent mechanical properties. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber of the present invention can be used to prepare an acoustic membrane. Due to its own self-adhesiveness, when it is composited with an aramid honeycomb, the acoustic membrane can be directly adhered to the aramid honeycomb to form a composite material, thereby improving the interfacial adhesion effect and the interfacial bonding strength; avoiding the use of adhesives, and avoiding the problem of pore blocking of the acoustic membrane caused by adhesives.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, in particular to a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber and a preparation method thereof. Background Art

[0002] Polyetheretherketone (PEEK) has excellent mechanical properties, high temperature resistance, and corrosion resistance. It can be melt-spun into PEEK fibers, which can then be polymerized into acoustic membranes. These membranes offer excellent sound insulation, sound absorption, and reflection, and are often used in the engine field. However, due to the high melting point of PEEK itself, acoustic membranes made from PEEK fibers cannot be thermally bonded to aramid honeycombs to form composite materials, limiting their application.

[0003] In order to composite an acoustic membrane made of polyetheretherketone fiber with an aramid honeycomb, the existing technology generally requires the use of an adhesive (such as an epoxy resin adhesive) to cure the acoustic membrane and the aramid honeycomb to prepare a composite material (Noise Reduction of honeycomb sandwich panels with acoustic mesh caps, Proc. Mtgs. Acoust., 2009, 8, 065002; Sound insulation performance of honeycombcore aluminum sandwich panels with flexible epoxy-based foam infill, Composite Structures, 2023, 319, 117149). In this composite material, the adhesion of the acoustic membrane made of polyetheretherketone fiber to the aramid honeycomb relies on the adhesive, which has a small contact surface and poor interfacial adhesion, resulting in poor mechanical properties of the composite material. At the same time, the adhesive is a liquid solution before curing and easily flows into the pores of the acoustic membrane, causing pore blockage.

[0004] Therefore, obtaining a polyetheretherketone fiber that has both excellent mechanical properties and self-adhesiveness is a technical problem that needs to be solved urgently in this field. Summary of the Invention

[0005] The present invention provides a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber is a composite fiber with a core-skin structure formed by using polyetheretherketone as a core layer and polyphenylene sulfone as a skin layer. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and excellent mechanical properties.

[0006] The present invention also provides a method for preparing a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber. The method can produce a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber having self-adhesiveness and excellent mechanical properties. The preparation method is simple and suitable for widespread promotion and application.

[0007] The present invention also provides an acoustic membrane, which is made of the above-mentioned self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, so that the acoustic membrane has self-adhesion and excellent mechanical properties.

[0008] A first aspect of the present invention provides a self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber having a sheath-core structure, wherein the core layer of the sheath-core structure is polyetheretherketone and the sheath layer is polyphenylenesulfone.

[0009] The self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber has a melt index of 60 to 120 g / 10 min, and a melt index of 20 to 80 g / 10 min.

[0010] The self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber as described above, wherein the mass ratio of the polyetheretherketone to the polyphenylenesulfone is (1-3):1.

[0011] The second aspect of the present invention provides a method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, comprising:

[0012] drying the polyetheretherketone and the polyphenylene sulfone respectively to obtain dried polyetheretherketone and dried polyphenylene sulfone;

[0013] Putting the dried polyetheretherketone into a first screw extruder to melt and perform a first extrusion to obtain a core layer;

[0014] Putting the dried polyphenylene sulfone into a second screw extruder to melt and perform a second extrusion to obtain a skin layer;

[0015] The core layer and the skin layer are weighed and squeezed into a skin-core spinning assembly according to a ratio to perform a spinning process, thereby obtaining self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers;

[0016] The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fiber is subjected to a drawing-heat setting treatment by a two-stage parallel drawing method to obtain the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a skin-core structure.

[0017] In the method for preparing the self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber, polyphenylenesulfone and polyetheretherketone are dried separately at 150° C. to 165° C. in a nitrogen atmosphere until the moisture content is less than 50 ppm.

[0018] In the method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, the temperature of the first extrusion is 370° C. to 400° C., and the pressure is 6 MPa to 8 MPa.

[0019] In the method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, the temperature of the second extrusion is 380° C. to 410° C., and the pressure is 6 MPa to 8 MPa.

[0020] In the method for preparing the self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber, the spinning temperature is 370° C. to 400° C. and the spinning speed is 1200 m / min to 2000 m / min.

[0021] As described above, the preparation method of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, during the stretching-heat setting treatment, the primary stretching temperature is 140°C to 160°C, the secondary stretching temperature is 210°C to 230°C, the stretching and winding speed is 750m / min to 850m / min, the stretching ratio is 1.5 times to 3.0 times, and the heat setting temperature is 240°C to 280°C.

[0022] A third aspect of the present invention provides an acoustic membrane, which is made of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber.

[0023] The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided by the present invention has polyetheretherketone as a core layer and polyphenylene sulfone as a skin layer to form a composite fiber with a skin-core structure, and the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and excellent mechanical properties. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber of the present invention can be used to prepare an acoustic membrane. Due to its own self-adhesiveness, it can be directly adhered to an aramid honeycomb to form a composite material, which can improve the interfacial adhesion effect and the interfacial bonding force, so that the composite material also has excellent mechanical properties; and the use of adhesives is avoided, thereby avoiding the problem of pore blocking in the acoustic membrane caused by adhesives. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a cross-sectional view of the self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber of Example 1 of the present invention, wherein a is polyphenylenesulfone, b is polyetheretherketone, and c is polyphenylenesulfone;

[0026] Figure 2 This is a cross-sectional view of a self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber according to Example 2 of the present invention, wherein a is polyphenylenesulfone, b is polyetheretherketone, and c is polyphenylenesulfone;

[0027] Figure 3 This is a cross-sectional view of a self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber according to Example 3 of the present invention, wherein a is polyphenylenesulfone, b is polyetheretherketone, and c is polyphenylenesulfone;

[0028] Figure 4 This is a cross-sectional view of the self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber of Example 4 of the present invention, wherein a is polyphenylenesulfone and b is polyetheretherketone. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0030] Unless otherwise specified, the raw materials and reagents used in the following examples can be obtained from commercial sources; the processes used, unless otherwise specified, are conventional processes in the art.

[0031] It should be noted that the descriptions involving “first”, “second”, etc. in the present invention are only for descriptive purposes and therefore cannot be understood as limiting the present invention.

[0032] A first aspect of the present invention provides a self-adhesive polyetheretherketone-polyphenylenesulfone composite fiber having a sheath-core structure, wherein the core layer of the sheath-core structure is polyetheretherketone and the sheath layer is polyphenylenesulfone.

[0033] In the present invention, the melting point of polyetheretherketone is 340°C.

[0034] In the present invention, polyphenylene sulfone has a glass transition temperature of 210°C to 225°C, can be melted at temperatures of 280°C to 320°C, and has a relatively high viscosity. The inventors have discovered through research that polyphenylene sulfone can be combined with polyetheretherketone to prepare a composite fiber having a sheath-core structure (self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber). Since polyetheretherketone has a melting point of 340°C, the composite fiber can be adhered using polyphenylene sulfone as a hot melt adhesive at temperatures below 340°C.

[0035] The present invention utilizes polyetheretherketone and polyphenylene sulfone to form a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a skin-core structure, wherein polyetheretherketone is used as the core layer of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, and polyphenylene sulfone is used as the skin layer of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber. The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and excellent mechanical properties.

[0036] In a specific embodiment, the melt index of polyetheretherketone is 60 to 120 g / 10 min, and the melt index of polyphenylene sulfone is 20 to 80 g / 10 min.

[0037] When the melt index of polyetheretherketone and the melt index of polyphenylene sulfone are within the above ranges, polyphenylene sulfone and polyetheretherketone have spinnability, and self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers with excellent self-adhesiveness and mechanical properties can be prepared by melt spinning.

[0038] For example, the melt index of polyetheretherketone can be any one of 60 g / 10 min, 70 g / 10 min, 80 g / 10 min, 90 g / 10 min, 100 g / 10 min and 120 g / 10 min, or a range consisting of any two thereof;

[0039] The melt index of polyphenylene sulfone may be any one of 20 g / 10 min, 30 g / 10 min, 40 g / 10 min, 50 g / 10 min, 60 g / 10 min, 70 g / 10 min, and 80 g / 10 min, or a range consisting of any two of these.

[0040] In some embodiments, the melt index of polyetheretherketone may preferably be 80 g / 10 min, and the melt index of polyphenylene sulfone may preferably be 40 g / 10 min.

[0041] In a specific embodiment, the mass ratio of polyetheretherketone to polyphenylene sulfone is (1-3):1.

[0042] When the parameters of the mass ratio of polyetheretherketone to polyphenylene sulfone are within the above range, a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with excellent self-adhesiveness and mechanical properties can be prepared. The inventors have shown through extensive research that if the mass ratio of polyetheretherketone to polyphenylene sulfone is greater than 3:1, there is too much core layer, the uniformity of the distribution of the core layer and the skin layer decreases, the tensile strength decreases, and the mechanical properties deteriorate; if the mass ratio of polyetheretherketone to polyphenylene sulfone is less than 1:1, the mechanical properties of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber using polyphenylene sulfone as the main raw material will also deteriorate. This may be because polyphenylene sulfone is an amorphous material and cannot provide strong mechanical support. Therefore, the mechanical properties of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber prepared using polyphenylene sulfone as the main raw material are reduced.

[0043] For example, the mass ratio of polyetheretherketone to polyphenylenesulfone may be any one of 1:1, 2:1 and 3:1, or a range consisting of any two of the ratios.

[0044] In some embodiments, the mass ratio of polyetheretherketone to polyphenylene sulfone may preferably be 2:1.

[0045] A second aspect of the present invention provides a method for preparing a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, comprising:

[0046] drying the polyetheretherketone and the polyphenylene sulfone respectively to obtain dried polyetheretherketone and dried polyphenylene sulfone;

[0047] Put the dried polyetheretherketone into a first screw extruder to melt, and perform a first extrusion to obtain a core layer;

[0048] The dried polyphenylene sulfone is placed in a second screw extruder to be melted and subjected to a second extrusion to obtain a skin layer;

[0049] The core layer and the skin layer are weighed and squeezed into a skin-core spinning assembly according to a ratio for spinning to obtain self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers;

[0050] The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers were subjected to a drawing-heat setting treatment by a two-stage parallel drawing method to obtain self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers with a skin-core structure.

[0051] The present invention does not particularly limit the specific forms of polyetheretherketone and polyphenylene sulfone, and they can be selected according to actual needs. In some embodiments, polyetheretherketone slices and polyphenylene sulfone slices can be selected.

[0052] The present invention does not specifically limit the instrument used for the above-mentioned measurement. In some embodiments, a metering pump can be selected for measurement.

[0053] The present invention adopts the above-mentioned preparation method to prepare a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with self-adhesiveness and excellent mechanical properties. The preparation method is simple in process and suitable for wide promotion and application.

[0054] In a specific embodiment, polyphenylene sulfone and polyetheretherketone are dried separately at 150° C. to 165° C. in a nitrogen atmosphere until the moisture content is less than 50 ppm.

[0055] When polyphenylene sulfone and polyetheretherketone are dried to a moisture content of less than 50 ppm, the core layer and skin layer prepared respectively have a low moisture content, which can prevent the formation of bubbles during the spinning process, induce the stress concentration of the spinning fluid and cause the occurrence of filament hair and broken yarns, and is beneficial to improving the mechanical properties of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber.

[0056] In a specific embodiment, the temperature of the first extrusion is 370° C. to 400° C., and the pressure is 6 MPa to 8 MPa.

[0057] When the parameters of the temperature and pressure of the first extrusion are within the above ranges, the melted polyetheretherketone can be completely filled in the screw of the first screw extruder, thereby preparing the core layer.

[0058] For example, the temperature of the first extrusion may be any one of 370° C., 380° C., 390° C., and 400° C., or a range consisting of any two thereof;

[0059] The pressure may be any one of 6 MPa, 7 MPa and 8 MPa, or a range consisting of any two of them.

[0060] In a specific embodiment, the temperature of the second extrusion is 380° C. to 410° C., and the pressure is 6 MPa to 8 MPa.

[0061] When the parameters of the temperature and pressure of the second extrusion are within the above ranges, the molten polyphenylene sulfone can completely fill the screw of the second screw extruder, thereby preparing the skin layer.

[0062] For example, the temperature of the first extrusion may be any one of 380° C., 390° C., 400° C., and 410° C., or a range consisting of any two thereof;

[0063] The pressure may be any one of 6 MPa, 7 MPa and 8 MPa, or a range consisting of any two of them.

[0064] In a specific embodiment, the spinning process is performed at a temperature of 370° C. to 400° C. and a speed of 1200 m / min to 2000 m / min.

[0065] When the parameters of the spinning process temperature and speed are within the above ranges, self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers can be continuously produced, and the produced self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers maintain excellent mechanical properties. The inventors have found through research that when the spinning process temperature is lower than 370°C, the viscosity of the self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers increases sharply and cannot be extruded; when the temperature is higher than 400°C, the viscosity of the self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers decreases sharply, the spinnability of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers decreases, and fiberization cannot be performed.

[0066] For example, the temperature of the spinning process may be any one of 370° C., 380° C., 390° C., and 400° C., or a range consisting of any two thereof;

[0067] The speed may be any one of 1200 m / min, 1300 m / min, 1400 m / min, 1500 m / min, 1600 m / min, 1700 m / min, 1800 m / min, 1900 m / min and 2000 m / min, or a range consisting of any two of them.

[0068] In a specific embodiment, during the stretching-heat setting treatment, the primary stretching temperature is 140°C to 160°C, the secondary stretching temperature is 210°C to 230°C, the stretching winding speed is 750m / min to 850m / min, the stretching ratio is 1.5 times to 3.0 times, and the heat setting temperature is 240°C to 280°C.

[0069] When the parameters of the primary drawing temperature, the secondary drawing temperature, the drawing winding speed, the drawing ratio and the heat setting temperature are within the above range during the drawing-heat setting process, a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with self-adhesiveness and excellent mechanical properties can be prepared. The inventors analyzed this and believed that the reasons may be: (1) Polyetheretherketone is used as the mechanical support layer, and its glass transition temperature is 140°C. Therefore, when the primary drawing temperature is 140°C to 160°C, the orientation degree of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber is significantly improved, and it has excellent mechanical properties; (2) The glass transition temperature of polyphenylene sulfone is 210°C to 225°C. Therefore, when the secondary drawing temperature is 210°C to 230°C, the orientation degree of polyphenylene sulfone can be increased, thereby improving the self-adhesiveness of the polyetheretherketone-polyphenylene sulfone composite fiber. The mechanical properties of polyetheretherketone-polyphenylene sulfone composite fibers are as follows: (1) After the first-stage drawing, the orientation degree of polyetheretherketone is high, and it can be crystallized at 210℃~230℃, forming a stable deorientation and inhibiting the deorientation of the molecular chain; (2) When the heat setting temperature is 240℃~280℃, the crystallization of polyetheretherketone is more complete and the mechanical properties are further improved; (3) When the drawing ratio is 1.5 times~3.0 times, the drawing stability is high, and a self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with self-adhesiveness and excellent mechanical properties can be prepared. In addition, the present inventors have found through extensive research that: (1) when the primary drawing temperature is higher than 160°C, the polyetheretherketone molecular chain moves violently, is easily tangled during the drawing process, and has reduced mechanical properties; (2) when the drawing ratio is less than 1.5 times, the drawing tension of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber is low, and the drawing stability is reduced; when the drawing ratio is higher than 3.0 times, the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber is prone to drawing fracture, and its mechanical properties are reduced.

[0070] A third aspect of the present invention provides an acoustic membrane made from the aforementioned self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber. The membrane exhibits self-adhesion and excellent mechanical properties. Due to its inherent self-adhesion, the membrane can be directly adhered to an aramid honeycomb to form a composite material, eliminating the need for adhesives.

[0071] The present invention is further described below through specific examples.

[0072] Example 1

[0073] In this embodiment, self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers were prepared by the following process:

[0074] Transferring polyetheretherketone slices with a melt index of 80 g / 10 min and polyphenylene sulfone slices with a melt index of 80 g / 10 min to a hot air drying device, respectively, and drying them at 165° C. under a nitrogen atmosphere for 6 hours to obtain dried polyetheretherketone slices and dried polyphenylene sulfone slices with a moisture content of less than 50 ppm;

[0075] The dried polyetheretherketone slices were placed into a first screw extruder, melted, and extruded at a temperature of 375° C. and a pressure of 6 MPa to obtain a core layer;

[0076] The dried polyphenylene sulfone slices were placed into a second screw extruder, melted, and extruded at a temperature of 400°C and a pressure of 6 MPa to obtain a skin layer;

[0077] A two-component sheath-core spinning method was used to measure the core layer and the sheath layer, respectively, and then squeezed into a sheath-core spinning assembly at a mass ratio of 2:1. The fibers were spun at a temperature of 390°C and a speed of 1200 m / min to obtain self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers. A metering pump was used for metering.

[0078] The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers were subjected to a drawing-heat setting treatment at a primary drawing temperature of 140°C, a secondary drawing temperature of 210°C, a drawing and winding speed of 800m / min, a drawing ratio of 2.0 times, and a heat setting temperature of 240°C to obtain the following: Figure 1 The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a sheath-core structure is shown.

[0079] Depend on Figure 1 It can be seen that the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and a skin-core structure, the distribution of the skin and core layers is unstable, and a large amount of polyphenylene sulfone enters the core layer, resulting in pulp penetration.

[0080] Example 2

[0081] In this embodiment, self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers were prepared by the following process:

[0082] Transferring polyetheretherketone slices with a melt index of 120 g / 10 min and polyphenylene sulfone slices with a melt index of 20 g / 10 min to a hot air drying device, respectively, and drying them at 160° C. under a nitrogen atmosphere for 6 hours to obtain dried polyetheretherketone slices and dried polyphenylene sulfone slices with a moisture content of less than 50 ppm;

[0083] The dried polyetheretherketone slices were placed into a first screw extruder, melted, and extruded at a temperature of 390° C. and a pressure of 6 MPa to obtain a core layer;

[0084] The dried polyphenylene sulfone slices were placed into a second screw extruder, melted, and extruded at a temperature of 400°C and a pressure of 6 MPa to obtain a skin layer;

[0085] A two-component sheath-core spinning method was used to measure the core layer and the sheath layer, respectively, and then squeezed into a sheath-core spinning assembly at a mass ratio of 2:1. The fibers were spun at a temperature of 390°C and a speed of 1200 m / min to obtain self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers. A metering pump was used for metering.

[0086] The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers were subjected to a drawing-heat setting treatment at a primary drawing temperature of 160°C, a secondary drawing temperature of 225°C, a drawing and winding speed of 800m / min, a drawing ratio of 2.1 times, and a heat setting temperature of 260°C to obtain the following: Figure 2 The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a sheath-core structure is shown.

[0087] Depend on Figure 2 It can be seen that the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and a skin-core structure. The distribution of the skin and core layers is unstable, and part of the polyphenylene sulfone enters the core layer, resulting in pulp penetration.

[0088] Example 3

[0089] In this embodiment, self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers were prepared by the following process:

[0090] Transferring polyetheretherketone chips with a melt index of 120 g / 10 min and polyphenylene sulfone chips with a melt index of 80 g / 10 min to a hot air drying device, respectively, and drying them at 160° C. under a nitrogen atmosphere for 6 hours to obtain dried polyetheretherketone chips and dried polyphenylene sulfone chips with a moisture content of less than 50 ppm;

[0091] The dried polyetheretherketone slices were placed into a first screw extruder, melted, and extruded at a temperature of 375° C. and a pressure of 6 MPa to obtain a core layer;

[0092] The dried polyphenylene sulfone slices were placed in a second screw extruder, melted, and extruded at a temperature of 390°C and a pressure of 6 MPa to obtain a skin layer;

[0093] A two-component sheath-core spinning method was used to measure the core layer and the sheath layer, respectively, and then squeezed into a sheath-core spinning assembly at a mass ratio of 2:1. The fibers were spun at a temperature of 385°C and a speed of 1200 m / min to obtain self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers. A metering pump was used for metering.

[0094] The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers were subjected to a drawing-heat setting treatment at a primary drawing temperature of 160°C, a secondary drawing temperature of 225°C, a drawing and winding speed of 800 m / min, a drawing ratio of 2.2 times, and a heat setting temperature of 260°C to obtain the following: Figure 3 The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a sheath-core structure is shown.

[0095] Depend on Figure 3 It can be seen that the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and a skin-core structure, the skin layer and the core layer are distributed relatively stably, and only a small amount of polyphenylene sulfone enters the core layer.

[0096] Example 4

[0097] In this embodiment, self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers were prepared by the following process:

[0098] Transferring polyetheretherketone chips with a melt index of 80 g / 10 min and polyphenylene sulfone chips with a melt index of 40 g / 10 min to a hot air drying device, respectively, and drying them at 160° C. under a nitrogen atmosphere for 6 hours to obtain dried polyetheretherketone chips and dried polyphenylene sulfone chips with a moisture content of less than 50 ppm;

[0099] The dried polyetheretherketone slices were placed into a first screw extruder, melted, and extruded at a temperature of 390° C. and a pressure of 6 MPa to obtain a core layer;

[0100] The dried polyphenylene sulfone slices were placed into a second screw extruder, melted, and extruded at a temperature of 400°C and a pressure of 6 MPa to obtain a skin layer;

[0101] A two-component sheath-core spinning method was used to measure the core layer and the sheath layer, respectively, and then squeezed into a sheath-core spinning assembly at a mass ratio of 2:1. The fibers were spun at a temperature of 390°C and a speed of 1200 m / min to obtain self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers. A metering pump was used for metering.

[0102] The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers were subjected to a drawing-heat setting treatment at a primary drawing temperature of 140°C, a secondary drawing temperature of 225°C, a drawing and winding speed of 800 m / min, a drawing ratio of 2.5 times, and a heat setting temperature of 260°C to obtain the following: Figure 4 The self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a sheath-core structure is shown.

[0103] Depend on Figure 4It can be seen that the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber has self-adhesiveness and a skin-core structure, and the skin layer and the core layer are evenly distributed without pulp cross-linking.

[0104] Comparative Example 1

[0105] The preparation of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example is basically the same as that in Example 4, except that:

[0106] The melt index of the polyetheretherketone chips is 50g / 10min.

[0107] Comparative Example 2

[0108] The preparation of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example is basically the same as that in Example 4, except that:

[0109] The melt index of polyetheretherketone chips is 130g / 10min.

[0110] Comparative Example 3

[0111] The preparation of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example is basically the same as that in Example 4, except that:

[0112] The melt index of the polyphenylene sulfone chips is 10 g / 10 min.

[0113] Comparative Example 4

[0114] The preparation of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example is basically the same as that in Example 4, except that:

[0115] The melt index of the polyphenylene sulfone chips was 90 g / 10 min.

[0116] Comparative Example 5

[0117] The preparation of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example is basically the same as that in Example 4, except that:

[0118] A two-component sheath-core spinning method was used to measure the core layer and the sheath layer separately and squeeze them into the sheath-core spinning assembly at a mass ratio of 0.8:1.

[0119] Comparative Example 6

[0120] The preparation of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example is basically the same as that in Example 4, except that:

[0121] The core layer and the cortex layer were measured separately by a two-component core-skin spinning method and then extruded into the core-skin spinning assembly in a mass ratio of 4:1.

[0122] Comparative Example 7

[0123] Preparation of polyetheretherketone-polyphenylene sulfone composite fiber provided in this comparative example:

[0124] Transferring polyetheretherketone chips with a melt index of 80 g / 10 min and polyphenylene sulfone chips with a melt index of 40 g / 10 min to a hot air drying device, respectively, and drying them at 160° C. under a nitrogen atmosphere for 6 hours to obtain dried polyetheretherketone chips and dried polyphenylene sulfone chips with a moisture content of less than 50 ppm;

[0125] The dried polyetheretherketone chips and the dried polyphenylene sulfone chips were weighed and placed together in a screw extruder at a mass ratio of 2:1 for melting, and extruded at a temperature of 390°C and a pressure of 6 MPa to obtain a melt; a metering pump was used for metering;

[0126] The melt was extruded into a sheath-core spinning assembly and spun at a temperature of 390° C. and a speed of 1200 m / min to obtain polyetheretherketone-polyphenylene sulfone nascent fibers;

[0127] A two-stage parallel drawing method was adopted, with the first-stage drawing temperature being 140°C, the second-stage drawing temperature being 225°C, the drawing winding speed being 800 m / min, the drawing ratio being 2.5 times, and the heat setting temperature being 260°C, to carry out a drawing-heat setting treatment on the self-adhesive polyetheretherketone-polyphenylenesulfone nascent fiber to obtain a polyetheretherketone-polyphenylenesulfone composite fiber.

[0128] Performance Characterization

[0129] The following performance tests were performed on the self-adhesive polyetheretherketone-polyphenylene sulfone composite fibers of Examples 1-4 and Comparative Examples 1-7, and the test results are shown in Table 1;

[0130] (1) Tensile strength (cN / dtex): Tested in accordance with GB / T 14344-2022 “Chemical Fibers: Test Method for Tensile Properties of Filament Filaments”;

[0131] (2) Denier (dtex): Tested in accordance with GB / T 14343-2008 “Chemical Fibers: Test Method for Linear Density of Filament Filaments”;

[0132] (3) Thermal shrinkage (%): Tested in accordance with GB / T 6505-2008 “Chemical Fibers: Test Method for Thermal Shrinkage of Filament Filaments”.

[0133] Table 1 Test results

[0134] project Spinnability Tensile strength (cN / dtex) Denier (dtex) Thermal shrinkage (%) Example 1 Can be spun 3.8 16.3 5.53 Example 2 Can be spun 4.1 15.5 4.94 Example 3 Can be spun 4.3 14.8 4.77 Example 4 Can be spun 5.3 13.0 3.24 Comparative Example 1 Unable to spin —— —— —— Comparative Example 2 Unable to spin —— —— —— Comparative Example 3 Unable to spin —— —— —— Comparative Example 4 Can be spun 3.2 17.2 6.54 Comparative Example 5 Can be spun 3.7 13.0 4.74 Comparative Example 6 Can be spun 3.7 13.0 3.98 Comparative Example 7 Can be spun 2.54 13.0 11.3

[0135] Analyze the data in the above table:

[0136] It can be seen from Examples 1 to 4 that the tensile strength of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber can reach up to 5.3 cN / dtex, which shows that the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber prepared in the examples of the present invention has excellent mechanical properties.

[0137] By comparing Comparative Examples 1-2 with Example 4, it can be seen that when the melt index of the polyetheretherketone chips is 50g / 10min, spinning is impossible. This may be because the melt index of the polyetheretherketone chips is too low and its viscosity is too high, which will cause the melted polyetheretherketone to break during extrusion and cannot be spun; when the melt index of the polyetheretherketone chips is 130g / 10min, spinning is impossible. This may be because the viscosity of the polyetheretherketone is too low, and the prepared core layer cannot be filled in the sheath-core spinning assembly, resulting in significant hair breakage and spinning.

[0138] By comparing Comparative Examples 3-4 with Example 4, it can be seen that when the melt index of the polyphenylene sulfone slice is 10 g / 10 min, spinning cannot be performed. This may be because the melt index of the polyphenylene sulfone slice is too low and its viscosity is too high, which will cause serious breakage of the melted polyphenylene sulfone during extrusion, and obvious hair breakage will occur during the spinning process, making it impossible to use; when the melt index of the polyphenylene sulfone slice is 90 g / 10 min, the mechanical properties of the prepared self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber decrease. This may be because the viscosity of the polyphenylene sulfone is too low, and part of the prepared cortex is not filled, resulting in pulping, which leads to a decrease in the mechanical properties of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber.

[0139] By comparing Comparative Examples 5-6 with Example 4, it can be seen that when the mass ratio of the core layer and the skin layer is 0.8:1, the mechanical properties of the prepared self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber decrease. It is speculated that this may be because the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber uses polyphenylene sulfone as the main raw material, and polyphenylene sulfone is an amorphous material and cannot provide strong mechanical support. Therefore, the mechanical properties of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber decrease; when the mass ratio of the core layer and the skin layer is 4:1, the mechanical properties of the prepared self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber decrease. It is speculated that this may be because there are too many core layers in the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, the uniformity of the distribution of the core layer and the skin layer decreases, the tensile strength decreases, and the mechanical properties of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber deteriorate.

[0140] Comparison of Comparative Example 7 with Example 4 shows that the polyetheretherketone-polyphenylene sulfone composite fiber prepared in Comparative Example 7 has no self-adhesiveness and significantly reduced mechanical properties. This may be because the compatibility of polyetheretherketone and polyphenylene sulfone is poor, and polyphenylene sulfone, as a material heterogeneity, easily causes stress concentration in the fiber, resulting in a significant decrease in the mechanical properties of the prepared polyetheretherketone-polyphenylene sulfone composite fiber. In addition, since the cortex of the polyetheretherketone-polyphenylene sulfone composite fiber is a mixture of polyetheretherketone and polyphenylene sulfone, the polyetheretherketone-polyphenylene sulfone composite fiber cannot melt at 320°C and therefore cannot be used as a self-adhesive composite fiber; and when the melting temperature is increased to 340°C, the polyetheretherketone in the polyetheretherketone-polyphenylene sulfone composite fiber will melt, causing the polyetheretherketone-polyphenylene sulfone composite fiber to mechanically disintegrate and be unable to maintain a fibrous shape.

[0141] In summary, the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber prepared in Example 4 has uniformly distributed skin and core layers, exhibits excellent mechanical properties (tensile strength greater than 5.2 cN / dtex), and can be used in high-density woven fabrics (tensile strength greater than 5.0 cN / dtex). Furthermore, even after the skin layer of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber is melted at high temperature, the core layer still maintains excellent mechanical properties.

[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber, characterized in that: It has a skin-core structure, wherein the core layer of the skin-core structure is polyetheretherketone and the skin layer is polyphenylene sulfone; The melt index of the polyetheretherketone is 60 to 120 g / 10min, and the melt index of the polyphenylene sulfone is 20 to 80 g / 10min; The mass ratio of the polyetheretherketone to the polyphenylene sulfone is (1-3):

1.

2. A method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 1, characterized in that: include: drying the polyetheretherketone and the polyphenylene sulfone respectively to obtain dried polyetheretherketone and dried polyphenylene sulfone; Putting the dried polyetheretherketone into a first screw extruder to melt and perform a first extrusion to obtain a core layer; Putting the dried polyphenylene sulfone into a second screw extruder to melt and perform a second extrusion to obtain a skin layer; The core layer and the skin layer are weighed and squeezed into a skin-core spinning assembly according to a ratio to perform a spinning process, thereby obtaining self-adhesive polyetheretherketone-polyphenylene sulfone nascent fibers; The self-adhesive polyetheretherketone-polyphenylene sulfone nascent fiber is subjected to a drawing-heat setting treatment by a two-stage parallel drawing method to obtain the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber with a skin-core structure.

3. The method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 2, characterized in that: The polyphenylene sulfone and polyetheretherketone were dried at 150° C. to 165° C. in a nitrogen atmosphere until the moisture content was less than 50 ppm.

4. The method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 2, characterized in that: The temperature of the first extrusion is 370° C. to 400° C., and the pressure is 6 MPa to 8 MPa.

5. The method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 2, characterized in that: The temperature of the second extrusion is 380° C. to 410° C., and the pressure is 6 MPa to 8 MPa.

6. The method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 2, characterized in that: The spinning process is performed at a temperature of 370° C. to 400° C. and a spinning speed of 1200 m / min to 2000 m / min.

7. The method for preparing the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 2, characterized in that: During the stretching-heat setting treatment, the primary stretching temperature is 140°C to 160°C, the secondary stretching temperature is 210°C to 230°C, the stretching and winding speed is 750m / min to 850m / min, the stretching ratio is 1.5 times to 3.0 times, and the heat setting temperature is 240°C to 280°C.

8. An acoustic membrane, characterized in that The acoustic membrane is made of the self-adhesive polyetheretherketone-polyphenylene sulfone composite fiber according to claim 1.

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