Hollow fiber treatment system, hollow fiber treatment agent, hollow fiber treatment method, and polysulfone resin composition

Abstract

To generate a recycled material of higher quality from hollow fibers.SOLUTION: A hollow fiber processing system performing a reproduction processing of hollow fibers containing polyvinylpyrrolidone comprises: a shredding device which shreds hollow fibers; a kneader which adds 0.03 to 1 pts.wt. of a compound having a phosphite structure and a hindered phenol structure in the same molecule to 0.2 to 5 pts.wt. of polyvinylpyrrolidone contained in the hollow fibers; and a granulator which forms pellets from hollow fiber chips to which the compound was added by the kneader.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a hollow fiber treatment system, a hollow fiber treatment agent, a hollow fiber treatment method, and a polysulfone resin composition. [Background technology]

[0002] In the above technical field, there is a demand for recycling the waste materials of hollow fibers made of polysulfone used in dialyzers. A method for recycling polysulfone is disclosed in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 02-121806 Summary of the Invention [Problem to be solved by the invention]

[0004] However, since the hollow fibers used in dialyzers contain polyvinylpyrrolidone, it has been difficult to produce high-quality recycled materials.

[0005] An object of the present invention is to provide a technique for solving the above-mentioned problems. [Means for solving the problem]

[0006] In order to achieve the above object, the hollow fiber processing system according to the present invention comprises: A hollow fiber processing system for performing a regeneration process on hollow fibers containing polyvinylpyrrolidone, a shredding device for shredding the hollow fibers; a kneading device for adding 0.03 to 1 part by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule to 0.2 to 5 parts by weight of polyvinylpyrrolidone contained in the hollow fibers; a granulator for shaping pellets from the hollow fiber pieces to which the compound has been added by the kneader; Equipped with.

[0007] In order to achieve the above object, the present invention Hollow fiber treatment stabilizer teeth, Stabilization treatment of hollow fibers containing polyvinylpyrrolidone for Hollow fiber processing Agent And, A compound having a phosphite structure and a hindered phenol structure in the same molecule A stabilizer for hollow fiber treatment comprising is.

[0008] In order to achieve the above object, the hollow fiber processing method according to the present invention comprises: For a pulverized hollow fiber material containing 0.2 to 5 parts by weight of polyvinylpyrrolidone, 0.03 to 1 part by weight of the above compound is added.

[0009] In order to achieve the above object, the polysulfone resin composition according to the present invention comprises: 100 parts by weight of polysulfone, 0.2 to 5 parts by weight of polyvinylpyrrolidone, 0.01 to 1 part by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule; Includes: [Effects of the Invention]

[0010] According to the present invention, higher quality recycled materials can be produced from hollow fibers. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a block diagram showing the configuration of a hollow fiber processing system according to a first embodiment. [Figure 2] 3 is a flowchart showing the processing flow of the hollow fiber processing system according to the first embodiment. [Figure 3] FIG. 3 is a diagram showing experimental results of the hollow fiber processing method according to the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the components described in the following embodiments are merely examples and are not intended to limit the technical scope of the present invention.

[0013] [First embodiment] A hollow fiber processing system 100 according to a first embodiment of the present invention will be described with reference to Fig. 1. As shown in Fig. 1, the hollow fiber processing system 100 comprises a shredding device 101, a kneading device 102, and a granulator 103.

[0014] The shredding device 101 cuts polysulfone (Poly arylether-aryl sulfone / PSF) hollow fibers 110 and their waste materials into small pieces (for example, 10 mm to 30 mm) that are discarded as waste materials during the dialyzer manufacturing process. The polysulfone hollow fibers 110 and their waste materials contain 1 to 5 wt % of polyvinylpyrrolidone (PVP), which is added during manufacturing.

[0015] The kneading device 102 produces a polysulfone resin molding material by kneading the chopped polysulfone pieces 130 with a specific compound, and stabilizes the polyvinylpyrrolidone added to the polysulfone. The polysulfone to which polyvinylpyrrolidone has been added and the stabilizer are both solids, and are generally mixed without melting the resin using a mixer such as a tumbler, blender, or mixer. At this stage, the polysulfone to which polyvinylpyrrolidone has been added and the stabilizer are in a non-uniformly mixed state. This polyvinylpyrrolidone does not have sufficient heat resistance to the high temperature conditions of approximately 300°C (the melting temperature of polysulfone) used in the subsequent granulation process (extrusion molding). In other words, it decomposes during the extrusion molding process, causing discoloration of the resin and the generation of odor. Therefore, after examining various stabilizers to reduce this discoloration and odor, it was found that a compound having a phosphite structure and a hindered phenol structure in the same molecule is particularly effective. Therefore, a compound having a phosphite structure and a hindered phenol structure in the same molecule was selected as the stabilizer added by the kneading extrusion device 102.

[0016] The granulator 103 melts the polysulfone resin molding material to which the stabilizer has been added and pelletizes it by extrusion molding. In this process, the stabilizer is uniformly dispersed in the polysulfone resin, preventing deterioration of the polyvinylpyrrolidone.

[0017] This allows polysulfone hollow fibers discarded in the dialyzer manufacturing process to be reused as heat-resistant molding materials. This embodiment can suppress discoloration and odor during pellet production, making it possible to provide high-quality recycled materials.

[0018] [Polysulfone resin molding material] Polysulfone resin molding material is For 100 parts by weight of hollow fiber pulverized product, It contains 0.2 to 5 parts by weight of polyvinylpyrrolidone, Furthermore, 0.03 to 1 part by weight of a stabilizer is added.

[0019] (stabilizer) The stabilizer used in this embodiment is a compound having a phosphite structure and a hindered phenol structure in the same molecule, such as 6-tert-butyl-4-[3-[(2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]propyl]-2-methylphenol.

[0020] This example is represented by the following structural formula: [ka] [In the formula, R1, R2, R4, and R5 each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group having 7 to 12 carbon atoms; R3 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom, or a -CHR6- group. R6 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. A represents an alkylene group having 2 to 8 carbon atoms or a -COR7- group. R7 represents a single bond or an alkylene group having 1 to 8 carbon atoms, and the CO marked with an * represents bonding to an oxygen atom in the phosphite structure in the above structural formula.] Either Y or Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.] When Y in the structural formula is a hydroxyl group, one of R4 and R5 represents an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group.

[0021] In the structural formula, two R1s, two R2s, and two R3s may be the same or different.

[0022] (The principle behind the stabilization of polyvinylpyrrolidone by the stabilizers mentioned above) Polyvinylpyrrolidone is classified as an olefin polymer. Under extremely high temperatures, such as those encountered during polysulfone processing, and in oxygen-containing atmospheres, polyvinylpyrrolidone readily undergoes decomposition. The metastable structural product (hydroperoxide) generated by the primary antioxidant either (1) reacts with the secondary antioxidant to form a stable structure, or (2) heat reactivates the hydroperoxide to form active hydroxyl or alkoxy radicals, initiating a chain reaction of decomposition. Because polysulfone processing temperatures of 300°C or higher are higher than the typical olefin processing temperatures of 150-230°C, it is believed that the hydroperoxide decomposition reaction occurs extremely quickly. Therefore, the presence of a secondary antioxidant in close proximity to the hydroperoxide provides a time advantage over this competitive reaction, rapidly stabilizing the generated hydroperoxide. Therefore, it is thought that stabilizers that have both the structure of a primary antioxidant and the structure of a secondary antioxidant in their molecules (e.g., Sumilizer GP) can provide more efficient stabilization than the combination of a primary antioxidant and a secondary antioxidant.

[0023] (Method of manufacturing polysulfone resin molding material) There are no particular limitations on the method for producing polysulfone pellets from dialyzer waste materials, and for example, the method shown in the flowchart of FIG. 2 can be applied.

[0024] In step S201, polysulfone, a heat-resistant stabilizer, and other optional components are mixed together or in multiple batches as needed, and then charged into the cylinder of a melt mixer such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, or a mixing roll.

[0025] Next, in step S202, the components charged into the cylinder are heated using the heater of the melt kneader to melt the polysulfone.

[0026] In step S203, the molten polysulfone and stabilizer are mixed by rotating the screw of the melt mixer to produce a mixture in which the added components are thoroughly mixed. During this process, the stabilizer inhibits decomposition of polyvinylpyrrolidone and suppresses odor and discoloration.

[0027] In step S204, the kneaded mixture is extruded through a die to form a string-like strand.

[0028] Next, in step S205, the strand is immersed in a water bath and immediately cooled.

[0029] Finally, in step S206, the cooled strand-like kneaded product is pelletized in a pelletizer to obtain a pelletized polysulfone resin molding material.

[0030] As described above, according to this embodiment, a higher quality polysulfone resin molding material can be obtained.

[0031] (Experimental equipment and conditions) Based on the hollow fiber processing system described above, experiments were conducted using the following experimental equipment and conditions.

[0032] Extruder: Plaenge Co., Ltd. single screw extruder PSV-30mm Processing temperature: 320-330℃ Screw rotation speed: 80 rpm Molding machine: FANUC Roboshot α-S50iA Hollow fiber crushed product A: Polysulfone 98.0 wt% + PVP content 2.0 wt% Hollow fiber crushed product B: Polysulfone 97.6 wt% + PVP content 2.4 wt% Here, the PVP content is a value converted from the total nitrogen amount analyzed using a Mitsubishi Chemical Analytech Co., Ltd. total nitrogen trace analyzer TN-2100H. L-value measuring device: Konica Minolta CM-3600A spectrophotometer MFR (melt flow rate): Fluidity when melted at 340℃ Load capacity: 2.16 kg Odor: The odor around the extruder when the stabilizer blend material is melted and mixed in the extruder is classified as ○, △, or × in order of least odor.

[0033] Example 1 To 100 parts by weight of the hollow fiber pulverized product A, 0.03 parts by weight of a compound having both a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 56.7, which was somewhat bright, and the odor was less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 and 8), or when these stabilizers were mixed (Comparative Examples 9 and 10).

[0034] Example 2 To 100 parts by weight of hollow fiber pulverized product A, 0.05 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 58.2, which was brighter than Example 1, and the odor was less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0035] Example 3 To 100 parts by weight of hollow fiber pulverized product A, 0.1 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 58.5, which was brighter than Example 2, and the odor was less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0036] Example 4 To 100 parts by weight of hollow fiber pulverized product A, 0.15 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 59.2, which was brighter than Example 3, and the odor was less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0037] Example 5 To 100 parts by weight of the hollow fiber pulverized product A, 0.3 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 61.9, which was brighter than Example 4, and the odor was much less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0038] Example 6 To 100 parts by weight of hollow fiber pulverized product A, 0.6 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 63.9, which was even brighter than Example 5, and the odor was significantly less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0039] Example 7 To 100 parts by weight of hollow fiber pulverized product A, 1 part by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 64.6, which was even brighter than Example 6, and the odor was significantly less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0040] Example 8 To 100 parts by weight of hollow fiber pulverized product B, 0.3 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 60.9, which was bright, and the odor was significantly less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0041] Example 9 To 100 parts by weight of hollow fiber pulverized product B, 0.6 parts by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule (here, Sumilizer GP is used as an example) was added as a stabilizer. The L value was 61.8, which was bright, and the odor was significantly less than when no stabilizer was added (Comparative Examples 1 and 2), when stabilizers 2 and 3, which have only a phosphite structure, were added (Comparative Examples 3 to 6), or when stabilizers 4 and 5, which have only a hindered phenol structure, were added (Comparative Examples 7 to 10).

[0042] (Comparative Examples 1 and 2) Pellets were produced without adding any stabilizer from 100 parts by weight of ground hollow fiber product A or ground hollow fiber product B. The L values ​​were 55.6 and 54.2, respectively, and the pellets were dark and had a strong odor.

[0043] (Comparative Example 3) To 100 parts by weight of hollow fiber pulverized product A, 0.05 parts by weight of phosphorus-based stabilizer 2 having only a phosphite structure was added. The L value was 43.5, which was quite dark, and the odor was strong.

[0044] (Comparative Examples 4 to 6) 0.05 to 0.15 parts by weight of phosphorus-based stabilizer 3 having only a phosphite structure was added to 100 parts by weight of hollow fiber pulverized product A. The L value was 55.7 to 54.5, and the mixture was dark and had a strong odor.

[0045] (Comparative Examples 7 to 8) To 100 parts by weight of hollow fiber pulverized product A, 0.3 parts by weight of stabilizers 4 and 5, each containing only a hindered phenol structure, was added. The L values ​​were 60.6 and 57.5, respectively, and the product was bright, but had a strong odor.

[0046] (Comparative Examples 9 to 10) To 100 parts by weight of hollow fiber pulverized product A, 0.05 parts by weight of phosphorus-based stabilizer 3, which has only a phosphite structure, and 0.3 parts by weight of stabilizers 4 and 5, which have only a hindered phenol structure, were added. The L values ​​were 60.4 and 57.8, respectively, and the product was bright, but had a strong odor.

[0047] (Experimental results) The results of the above-mentioned Examples and Comparative Examples are summarized in Figure 3. From the above-mentioned Examples and Comparative Examples, it was confirmed that high-quality recycled hollow fiber materials can be obtained by using a compound having a phosphite structure and a hindered phenol structure in the same molecule.

[0048] <Application> Polysulfone resin molding materials produced by the above-mentioned method can be used in the medical field for ventilators, artificial dentures, and endoscope parts. In the food industry, they can be used for microwave oven parts, coffee makers, refrigeration and thawing trays, cookers, etc. In the automotive field, they can be used for auto phases and light parts, and in the electronics field, they can be used for connectors, switches, coil bobbins, IC carriers, bushings, etc.

[0049] The use of such recycled materials can reduce the environmental impact (emission of greenhouse gases) throughout the life cycle of hollow fibers, from their manufacture to their use and disposal.

[0050] [Other embodiments] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the technical scope of the present invention.

Claims

1. A hollow fiber processing system for performing a regeneration process on hollow fibers containing polyvinylpyrrolidone, a shredding device for shredding the hollow fibers; a kneading device for adding 0.03 to 1 part by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule to 0.2 to 5 parts by weight of polyvinylpyrrolidone contained in the hollow fibers; a granulator for shaping pellets from the hollow fiber pieces to which the compound has been added by the kneader; A hollow fiber processing system comprising:

2. A stabilizer for hollow fiber treatment, which contains polyvinylpyrrolidone and is used to perform a stabilization treatment of hollow fibers, A stabilizer for hollow fiber treatment, comprising a compound having a phosphite structure and a hindered phenol structure in the same molecule.

3. A stabilizer for treating hollow fibers, comprising the compound of claim 2 having the following structural formula: 【Chemistry 1】 [In the formula, R 1 , R 2 , R 4 and R 5 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group having 7 to 12 carbon atoms; R 3 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom, or -CHR 6 represents a - group. 6 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. A represents an alkylene group having 2 to 8 carbon atoms or *-COR 7 represents a - group. 7 represents a single bond or an alkylene group having 1 to 8 carbon atoms, and the CO marked with an * represents bonding to the oxygen atom of the phosphite structure in the above structural formula. Either Y or Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

4. When Y in the structural formula of claim 3 is a hydroxyl group, R 4 and R 5 wherein one of the alkyl groups is a C3-C8 alkyl group, a C5-C8 cycloalkyl group, a C6-C12 alkylcycloalkyl group, a C7-C12 aralkyl group, or a phenyl group.

5. The two R in the structural formula of claim 3 1 , two R 2 , two R 3 A stabilizer for treating hollow fibers, comprising the compound according to claim 3 or 4, wherein each of

6. A stabilizer for hollow fiber treatment comprising the compound according to claim 3, which is 6-tert-butyl-4-[3-[(2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]propyl]-2-methylphenol.

7. For a pulverized hollow fiber material containing 0.2 to 5 parts by weight of polyvinylpyrrolidone, A method for treating hollow fibers, comprising adding 0.03 to 1 part by weight of the compound according to claim 2.

8. For a pulverized hollow fiber material containing 0.2 to 5 parts by weight of polyvinylpyrrolidone, A method for treating hollow fibers, comprising adding 0.3 to 1 part by weight of the compound according to claim 2.

9. 100 parts by weight of polysulfone, 0.2 to 5 parts by weight of polyvinylpyrrolidone; 0.01 to 1 part by weight of a compound having a phosphite structure and a hindered phenol structure in the same molecule; A polysulfone resin composition comprising:

10. The polysulfone resin composition according to claim 9, wherein the compound has the following structural formula: 【Chemistry 2】 [In the formula, R 1 , R 2 , R 4 and R 5 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group having 7 to 12 carbon atoms; R 3 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. X represents a single bond, a sulfur atom, or -CHR 6 represents a - group. 6 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a cycloalkyl group having 5 to 8 carbon atoms. A represents an alkylene group having 2 to 8 carbon atoms or *-COR 7 represents a - group. 7 represents a single bond or an alkylene group having 1 to 8 carbon atoms, and the CO marked with an * represents bonding to the oxygen atom of the phosphite structure in the above structural formula. Either Y or Z represents a hydroxyl group, an alkoxy group having 1 to 8 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms, and the other represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

11. When Y in the structural formula of claim 10 is a hydroxyl group, R 4 and R 5 and one of the groups represents an alkyl group having 3 to 8 carbon atoms, a cycloalkyl group having 5 to 8 carbon atoms, an alkylcycloalkyl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or a phenyl group.

12. The two R in the structural formula of claim 10 1 , two R 2 , two R 3 The polysulfone resin composition according to claim 10, wherein

13. The polysulfone resin composition according to claim 10, which is 6-tert-butyl-4-[3-[(2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepin-6-yl)oxy]propyl]-2-methylphenol.

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