Stirring kettle for in-situ dyeing of PBO polymer

Abstract

The utility model discloses a stirring kettle for in-situ dyeing of a PBO polymer, which belongs to the technical field of stirring kettles and comprises a kettle body, a feeding port and a driving motor are arranged at the upper end of the kettle body, the driving motor is connected with a stirring shaft through a coupler, the stirring shaft extends into the kettle body and is connected with a stirring frame, stirring blades are arranged on the stirring frame, and a discharging port is arranged at the lower end of the kettle body. The discharging port is connected with a conical spiral conveyor, the lower end of the stirring shaft is connected with a first spiral belt shaft through a one-way driving mechanism, the first spiral belt shaft is arranged in the conical spiral conveyor, and a first spiral belt is arranged on the first spiral belt shaft. The PBO polymer and the pigment are both contained in the kettle body through the feeding port, the motor rotates forwards to mix materials (the conical spiral conveyor is static) when rotating forwards, high-speed and high-efficiency mixing of the pigment and the polymer materials is achieved, after the pigment is mixed, the motor rotates backwards to drive the stirring shaft to rotate, and the stirring frame, the stirring blades and the first spiral belt shaft rotate backwards, so that the stirring effect is achieved. And the mixed material in the kettle body is discharged from the discharge hole through the conical spiral conveyor.

Description

Technical Field

[0001] The utility model belongs to the technical field of stirred kettles, and in particular relates to a stirred kettle used for in-situ dyeing of PBO polymers. Background Art

[0002] Poly(p-phenylene benzobisoxazole) (PBO) fiber is a high-performance organic fiber. It possesses excellent properties, including high strength, high modulus, high heat resistance, and extreme flame retardancy. Therefore, it holds great promise for applications in aerospace, special protective equipment, and high-end composite materials. To enhance the potential of PBO fibers for specialized applications, the preparation of PBO fibers in different colors has been a key research focus. However, the highly oriented molecular chains and dense crystalline structure lead to inherent dyeing defects, making conventional synthetic fiber dyeing methods difficult to achieve. Consequently, pigment printing is the only method used for dyeing. However, the resulting monotonous colors and poor color fastness severely restrict its application.

[0003] Currently, in-situ dyeing of PBO polymers is a research hotspot for PBO fiber dyeing. For example, patent publication CN109778342A discloses a method for in-situ dyeing of poly(p-phenylene benzobisoxazole) fibers. This method involves preparing a pigment / TPA / PPA slurry with some reactive monomers, pigment, and polyphosphoric acid. This slurry is then post-polymerized and dyed in a twin-screw extruder. In actual production, due to the varying solubility of different pigments in PPA, the slurry working conditions for different pigment configurations may vary. Furthermore, adding the pigment solution to the polymer in the twin-screw extruder can result in fibers with short mixing and dyeing times, uneven coloring, and reduced performance.

[0004] In the poly(p-phenylenebenzobisoxazole) (PBO) solution dyeing process, nanoscale inorganic pigments (such as carbon black and ferro-titanium brown) or high-temperature-resistant organic dyes (such as anthraquinone derivatives) must be incorporated into the polymerization solution midway through the polymerization reaction. This process faces two major challenges: 1) Mixing difficulties caused by high-viscosity materials. During the PBO polymer polymerization process, the material viscosity gradually changes, and efficient mixing after the pigment is added is critical for uniform fiber coloring. 2) The risk of failure in conveying high-viscosity materials. The gradual increase in material viscosity in the late stages of polymerization, coupled with the pigment's impact on the polymer system, also poses a challenge to in-situ dyeing. Therefore, this utility model addresses the issue of improved mixing and stirring kettles for dyeing high-viscosity materials, particularly PBO, and develops a suitable stirred kettle for in-situ dyeing of PBO polymers.

[0005] The Chinese patent with publication number CN219559622U and publication date 2023-08-22 discloses a stirred reactor for a poly(p-phenylene benzobisoxazole)-polyphosphoric acid system, comprising a kettle body, a feeding port and a drive motor provided at the upper end of the kettle body, the drive motor being connected to a stirring shaft via a coupling, the stirring shaft extending into the kettle body and connected to a stirring frame, the stirring frame being provided with stirring blades, a guide baffle being further provided inside the kettle body, a flow gap being formed between the guide baffle and the outer side of the stirring frame, and a discharge port being provided at the lower end of the kettle body. The stirred reactor cannot meet the requirements of high-speed mixing of the material system in the kettle after the addition of the pigment, and efficient discharge of the pigment polymer under low speed conditions. The in-situ dyeing of PBO polymers in the kettle mainly has two stages. During the pigment addition and mixing stage, the system viscosity is relatively low, and a short time is required to complete high-speed mixing. Therefore, the stirring in the kettle needs to be designed with a single function. That is, the stirring in the kettle rotates forward and mixes at high speed, and the lower screw is stopped to avoid ineffective power consumption and prevent the pigment from settling into the single screw and affecting the output of the single screw. In the pigment polymer delivery stage, after the pigment is added and evenly dispersed, the viscosity of the polymer system gradually increases. In order to prevent the stirring heat generated by high speed from making the system temperature and viscosity uncontrollable, a dual-function collaborative design of low-speed feeding of stirring in the kettle and extrusion of the screw is required. That is, low-speed feeding of stirring in the reverse direction and collaborative extrusion of the lower screw to output the material is required. Utility Model Content

[0006] The purpose of the utility model is to solve the problems of the prior art and provide a stirring kettle for in-situ dyeing of PBO polymers. The PBO polymer and the pigment are both fed into the kettle body through a feeding port. The motor drives the stirring shaft to rotate, and the stirring shaft drives the stirring frame and the stirring blades to rotate. When the motor rotates forward, the mixing is carried out forward (the conical screw conveyor is stationary), thereby achieving high-speed and efficient mixing of the pigment and the polymer material. When the mixing of the pigment is completed, the motor rotates in the reverse direction to drive the stirring shaft to rotate, and the stirring frame, the stirring blades and the first ribbon shaft rotate in the reverse direction to discharge the mixed material in the kettle body from the discharge port through the conical screw conveyor.

[0007] The utility model is achieved through the following technical solutions:

[0008] A stirring kettle for in-situ dyeing of PBO polymers comprises a kettle body, wherein the upper end of the kettle body is provided with a feeding port and a driving motor, the driving motor is connected to a stirring shaft via a coupling, the stirring shaft extends into the kettle body and is connected to a stirring frame, the stirring frame is provided with stirring blades, and the lower end of the kettle body is provided with a discharge port; the discharge port is connected to a conical screw conveyor, the lower end of the stirring shaft is connected to a first spiral ribbon shaft via a one-way drive mechanism, the first spiral ribbon shaft is provided in the conical screw conveyor, and the first spiral ribbon shaft is provided with a first spiral ribbon.

[0009] Preferably, the one-way drive mechanism adopts a ratchet mechanism or a one-way clutch.

[0010] Preferably, a single screw discharger is provided at the lower end of the conical screw conveyor.

[0011] Preferably, the second spiral ribbon shaft on the single-screw discharging machine is connected to the first spiral ribbon shaft.

[0012] Preferably, a flow guide baffle is further provided inside the kettle body, and a flow gap is formed between the flow guide baffle and the outer side of the stirring frame.

[0013] Preferably, a plurality of guide baffles are provided; the plurality of guide baffles are evenly arranged at the lower end of the inner wall of the kettle body.

[0014] Preferably, the flow gap is 25-50 mm.

[0015] Preferably, a heat exchange jacket is further provided outside the kettle.

[0016] Preferably, the stirring frame is a squirrel cage stirring frame.

[0017] Preferably, the stirring blade is a frame structure.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0019] 1. The utility model provides a stirring kettle for in-situ dyeing of PBO polymer. PBO polymer and pigment are both charged into the kettle through a feeding port. A motor drives the stirring shaft to rotate, which in turn drives the stirring frame and stirring blades to rotate. When the motor rotates forward, the mixing is carried out in the forward direction (the conical screw conveyor is stationary), thereby achieving high-speed and efficient mixing of the pigment and polymer materials. When the pigment is mixed, the motor rotates in the reverse direction to drive the stirring shaft to rotate, and the stirring frame, stirring blades and first ribbon shaft rotate in the reverse direction to discharge the mixed material in the kettle from the discharge port through the conical screw conveyor.

[0020] 2. The utility model provides a stirring kettle for in-situ dyeing of PBO polymers, which realizes seamless conversion of the dual-function modes of high-speed mixing by the upper stirring frame and stirring blades (the conical screw conveyor is stationary) and conveying by the conical screw conveyor (the stirring frame and stirring blades cooperate to reverse) through the forward and reverse switching of a single driving source.

[0021] 3. The utility model provides a stirring kettle for in-situ dyeing of PBO polymers. The first spiral belt has zero resistance during mixing, reducing power loss; a single motor realizes dual functions, saving the cost of hydraulic / electromagnetic clutch system; pure mechanical transmission avoids the risk of electronic control failure.

[0022] 4. The utility model provides a stirring kettle for in-situ dyeing of PBO polymers. The setting of the single-screw discharger makes the extrusion of high-viscosity mixed materials in the kettle more efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural diagram of the utility model;

[0024] Among them: 1. Kettle body; 2. Feeding port; 3. Drive motor; 4. Stirring shaft; 5. Stirring frame; 6. Stirring blades; 7. Discharge port; 8. Conical screw conveyor; 9. One-way drive mechanism; 10. First screw shaft; 11. First screw; 12. Single screw discharger; 13. Second screw shaft; 14. Guide baffle; 15. Flow gap; 16. Heat exchange jacket. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below with reference to the embodiments, but the embodiments of the present invention are not limited thereto.

[0026] Example 1

[0027] like Figure 1 As shown, this embodiment provides a stirring kettle for in-situ dyeing of PBO polymers, comprising a kettle body 1, wherein a feeding port 2 and a drive motor 3 are provided at the upper end of the kettle body 1, the drive motor 3 is connected to a stirring shaft 4 through a coupling, the stirring shaft 4 extends into the kettle body 1 and is connected to a stirring frame 5, the stirring frame 5 is provided with stirring blades 6, and a discharge port 7 is provided at the lower end of the kettle body 1; the discharge port 7 is connected to a conical screw conveyor 8, the lower end of the stirring shaft 4 is connected to a first spiral ribbon shaft 10 through a one-way drive mechanism 9, the first spiral ribbon shaft 10 is arranged in the conical screw conveyor 8, and the first spiral ribbon shaft 10 is provided with a first spiral ribbon 11.

[0028] Example 2

[0029] This embodiment provides a stirring kettle for in-situ dyeing of PBO polymers, comprising a kettle body 1, wherein a feeding port 2 and a drive motor 3 are provided at the upper end of the kettle body 1, wherein the drive motor 3 is connected to a stirring shaft 4 via a coupling, and the stirring shaft 4 extends into the kettle body 1 and is connected to a stirring frame 5, wherein the stirring frame 5 is provided with stirring blades 6, and a discharge port 7 is provided at the lower end of the kettle body 1; the discharge port 7 is connected to a conical screw conveyor 8, and the lower end of the stirring shaft 4 is connected to a first spiral ribbon shaft 10 via a one-way drive mechanism 9, wherein the first spiral ribbon shaft 10 is arranged in the conical screw conveyor 8, and a first spiral ribbon 11 is provided on the first spiral ribbon shaft 10.

[0030] The one-way drive mechanism 9 adopts a ratchet mechanism or a one-way clutch. Any commonly used one-way drive mechanism such as a ratchet mechanism or a one-way clutch in the prior art can be implemented to meet the technical requirements of the one-way drive.

[0031] Wherein, a single screw discharger 12 is provided at the lower end of the conical screw conveyor 8 .

[0032] The second ribbon shaft 13 on the single screw discharger 12 is connected to the first ribbon shaft 10. The single screw discharger 12 includes a vertical spiral shell and a second ribbon shaft 13 disposed in the vertical spiral shell, wherein the second ribbon shaft 13 is provided with a second ribbon.

[0033] A flow guide baffle 14 is further provided inside the kettle body 1, and a flow gap 15 is formed between the flow guide baffle 14 and the outer side of the stirring frame 5. The flow guide baffle 14 is provided on the inner wall of the kettle body 1 through a fixing member.

[0034] There are multiple guide baffles 14 ; the multiple guide baffles 14 are evenly arranged at the lower end of the inner wall of the kettle body 1 .

[0035] Wherein, the flow gap 15 is 25-50 mm.

[0036] Wherein, a heat exchange jacket 16 is further provided outside the kettle body 1 .

[0037] The stirring frame 5 is a squirrel cage stirring frame 5 .

[0038] Wherein, the stirring blade 6 is a frame structure.

[0039] Among them, the drive motor 3, coupling, one-way drive mechanism 9, conical screw conveyor 8, single screw discharger 12, and heat exchange jacket 16 are all existing technologies and will not be described in detail here.

[0040] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0041] 1. The present invention provides a stirred kettle for in-situ dyeing of PBO polymers. The PBO polymer and pigment are both fed into the kettle body 1 through the feeding port 2. The motor drives the stirring shaft 4 to rotate, and the stirring shaft 4 drives the stirring frame 5 and the stirring blades 6 to rotate. When the motor rotates forward, the mixing is carried out forward (the conical screw conveyor 8 is stationary), thereby achieving high-speed and efficient mixing of the pigment and polymer materials. When the pigment is mixed, the motor rotates in the reverse direction to drive the stirring shaft 4 to rotate, and the stirring frame 5, the stirring blades 6 and the first ribbon shaft 10 rotate in the reverse direction to discharge the mixed material in the kettle body 1 from the discharge port 7 through the conical screw conveyor 8.

[0042] 2. The present invention provides a stirring kettle for in-situ dyeing of PBO polymers, which realizes seamless conversion of the dual-function modes of high-speed mixing of the upper stirring frame 5 and stirring blades 6 (the conical screw conveyor 8 is stationary) and conveying of the conical screw conveyor 8 (the stirring frame 5 and stirring blades 6 are coordinated and reversed) by switching the forward and reverse directions of a single driving source.

[0043] 3. The present invention provides a stirring kettle for in-situ dyeing of PBO polymers. The first spiral belt 11 has zero resistance during mixing, reducing power loss. A single motor achieves dual functions, saving the cost of hydraulic / electromagnetic clutch systems. Pure mechanical transmission avoids the risk of electronic control failure.

[0044] 4. The present invention provides a stirring kettle for in-situ dyeing of PBO polymers. The arrangement of the single-screw discharger 12 enables more efficient extrusion of the high-viscosity mixed material in the kettle body 1.

[0045] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A stirring kettle for in-situ dyeing of PBO polymers, comprising a kettle body (1), wherein the upper end of the kettle body (1) is provided with a feeding port (2) and a driving motor (3), wherein the driving motor (3) is connected to a stirring shaft (4) via a coupling, wherein the stirring shaft (4) extends into the kettle body (1) and is connected to a stirring frame (5), wherein the stirring frame (5) is provided with stirring blades (6), and the lower end of the kettle body (1) is provided with a discharge port (7); characterized in that: The discharge port (7) is connected to the conical screw conveyor (8), and the lower end of the stirring shaft (4) is connected to the first screw ribbon shaft (10) through a one-way drive mechanism (9). The first screw ribbon shaft (10) is arranged in the conical screw conveyor (8), and the first screw ribbon shaft (10) is provided with a first screw ribbon (11).

2. The stirred tank for in-situ dyeing of PBO polymer according to claim 1, characterized in that: The one-way driving mechanism (9) adopts a ratchet mechanism or a one-way clutch.

3. The stirred tank for in-situ dyeing of PBO polymer according to claim 1, characterized in that: A single screw discharger (12) is provided at the lower end of the conical screw conveyor (8).

4. A stirred tank for in-situ dyeing of PBO polymer according to claim 3, characterized in that: The second spiral ribbon shaft (13) on the single-screw discharger (12) is connected to the first spiral ribbon shaft (10).

5. The stirred tank for in-situ dyeing of PBO polymer according to claim 1, characterized in that: A flow guide baffle (14) is further provided inside the kettle body (1), and a flow gap (15) is formed between the flow guide baffle (14) and the outside of the stirring frame (5).

6. The stirred tank for in-situ dyeing of PBO polymer according to claim 5, characterized in that: A plurality of guide baffles (14) are provided; the plurality of guide baffles (14) are evenly arranged at the lower end of the inner wall of the kettle body (1).

7. The stirred tank for in-situ dyeing of PBO polymer according to claim 6, characterized in that: The flow gap (15) is 25-50 mm.

8. The stirred tank for in-situ dyeing of PBO polymer according to claim 1, characterized in that: A heat exchange jacket (16) is also provided outside the kettle body (1).

9. The stirred tank for in-situ dyeing of PBO polymer according to claim 1, characterized in that: The stirring frame (5) is a squirrel cage type stirring frame (5).

10. The stirred tank for in-situ dyeing of PBO polymer according to claim 1, characterized in that: The stirring blade (6) is a frame structure.

Images