A method for pretreating fibers for dialysis paper and dialysis paper

Abstract

This invention relates to the field of dialysis paper technology, and particularly to a fiber pretreatment method for dialysis paper and dialysis paper itself. The fiber pretreatment method for dialysis paper includes the following steps: Step 1, weighing softwood fibers, broadwood fibers, and regenerated fibers and placing them in deionized water, stirring thoroughly to obtain a mixture; Step 2, adding an initiator to the mixture, heating to 35-45°C, and mixing evenly; Step 3, adding modified nanoparticles to the mixture from Step 2, and stirring continuously for 4-6 hours; Step 4, after the reaction is complete, washing, filtering, and drying to obtain the pretreated fibers for dialysis paper. The fiber pretreatment method for dialysis paper proposed in this invention can uniformly attach nanoparticles to the fiber surface. When the nanoparticles are compressed by the fibers, they can aggregate towards the "gaps" between the fibers, preventing excessively large gaps between the fibers and avoiding the passage of bacteria or dust through the dialysis paper.

Description

Technical Field

[0001] This invention relates to the field of dialysis paper technology, and more particularly to a fiber pretreatment method for dialysis paper and dialysis paper. Background Technology

[0002] Medical device sterilization packaging can be divided into protective packaging and aseptic barrier systems, with the aseptic barrier system being a key component and a primary focus of the sterilization packaging industry. Constructing an aseptic barrier system depends on the selection and processing of suitable dialysis packaging materials. Compared to non-woven fabrics, medical dialysis paper offers advantages such as low cost and ease of use. It can be heat-sealed or glue-sealed with film materials such as PE (polyethylene) and PP (polypropylene), and is therefore commonly used as a sterilization packaging material for medical devices in the medical packaging industry. With the development of papermaking technology, medical dialysis paper has been widely applied in aseptic barrier systems.

[0003] The production of medical dialysis paper requires high-performance paper properties, including strength, antibacterial properties, and air permeability. Air permeability is a particularly important performance parameter and currently represents a significant technical challenge in this field in China. This is primarily because domestic sterilization of packaging materials mainly employs ETO (ethylene oxide) sterilization and high-temperature moist heat steam sterilization. The sterilization effectiveness and rate of these two methods are highly dependent on the paper's air permeability. These methods require the paper to possess excellent air permeability while having small pore sizes, enabling the prepared sterilized packaging to block bacteria and dust from entering while allowing ethylene oxide gas or vapor to permeate, thereby achieving the sterilization of the medical devices and items within the packaging.

[0004] The air permeability of paper is affected not only by the fibers themselves, such as fiber thickness, length, shape, surface properties, and dispersion, but also by the stacking gaps between fibers. Since fibers are approximately cylindrical and there is line contact between them, uneven fiber surfaces, such as depressions or protrusions, can create noticeable "gaps" between fibers. These gaps can allow bacteria or dust to penetrate the dialysis paper, affecting its quality. Therefore, we propose a fiber pretreatment method for dialysis paper and the resulting dialysis paper. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a fiber pretreatment method for dialysis paper and dialysis paper.

[0006] A fiber pretreatment method for dialysis paper includes the following steps:

[0007] Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture.

[0008] Step 2: Add the initiator to the mixture, heat to 35-45℃, and mix thoroughly;

[0009] Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 4 to 6 hours;

[0010] Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper;

[0011] The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is (0.003~0.005):1;

[0012] The ratio of the modified nanoparticles in step 3 to the total mass of the fibers in step 1 is (0.02~0.06):1.

[0013] Preferably, the method for preparing the modified nanoparticles includes the following steps: mixing the quaternary ammonium salt silane coupling agent with the nanoparticles using a ball mill to obtain the modified nanoparticles;

[0014] The nanoparticles are one or more of nano zinc oxide, nano titanium oxide, and nano aluminum oxide.

[0015] The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is (0.05-0.12):1.

[0016] The general formula of the quaternary ammonium salt silane coupling agent is:

[0017] (R1)3Si-(CH2)nN + (R2)(R3)((CH2) m OCOCH=CH2)X -

[0018] Wherein, R1 is methoxy or ethoxy, and R2 and R3 are alkyl;

[0019] m and n are integers greater than or equal to 1;

[0020] X represents a halide anion.

[0021] Preferably, during the ball milling process, the ball milling is carried out for 1 to 2 hours at a ball-to-material ratio of 10 to 20:1, and the ball mill speed is 500 to 700 rpm.

[0022] Preferably, the particle size of the nanoparticles is 50–200 nm.

[0023] Preferably, in step 1, the mass ratio of coniferous fiber, broadleaf fiber and regenerated fiber is (5-6):1:(0.8-1.2).

[0024] Preferably, the regenerated fiber has a fineness of 1.2 to 1.5 dtex and a length of 32 to 38 mm, and the regenerated fiber is a cotton-type regenerated cellulose short fiber.

[0025] Preferably, the initiator is one of ammonium persulfate or sodium persulfate.

[0026] Preferably, in step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is (30-60):1.

[0027] Preferably, a dialysis paper is prepared from fibers treated according to the above-described fiber pretreatment method for dialysis paper.

[0028] The beneficial effects of this invention are:

[0029] 1. The fiber pretreatment method for dialysis paper proposed in this invention involves mixing softwood fibers, broadwood fibers, and regenerated fibers in appropriate proportions and then modifying them. The dialysis paper prepared from the pretreated fibers has uniform pores and good air permeability, which is conducive to the smooth progress of subsequent sterilization operations.

[0030] 2. The fiber pretreatment method for dialysis paper proposed in this invention can uniformly attach nanoparticles to the fiber surface. The nanoparticles are "flexibly" attached to the fiber surface through a quaternary ammonium salt silane coupling agent. When the pretreated fibers are subsequently made into dialysis paper, the nanoparticles can gather into the "gaps" between the fibers after being squeezed by the fibers, so that there are no excessive gaps between the fibers, avoiding the situation where bacteria or dust pass through the dialysis paper. The dialysis paper produced has uniform pore size, and the nanoparticles and the fiber surface form uniformly distributed micropores, ensuring the air permeability of the dialysis paper.

[0031] 3. The fiber pretreatment method for dialysis paper proposed in this invention treats the fibers with a quaternary ammonium salt silane coupling agent. The quaternary ammonium salt silane coupling agent undergoes free radical graft copolymerization with the hydroxyl groups on the fibers, which gives the treated fibers certain antibacterial properties and makes them less prone to adverse reactions such as yellowing during use. Detailed Implementation

[0032] The present invention will be further explained below with reference to specific embodiments.

[0033] In Example 1, a fiber pretreatment method for dialysis paper includes the following steps:

[0034] Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture.

[0035] Step 2: Add the initiator to the mixture, heat to 35°C, and mix thoroughly;

[0036] Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 4 hours;

[0037] Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper;

[0038] The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is 0.003:1;

[0039] In step 3, the ratio of the total mass of the modified nanoparticles to the total mass of the fibers in step 1 is 0.02:1.

[0040] The preparation method of modified nanoparticles includes the following steps: mixing quaternary ammonium salt silane coupling agent with nanoparticles thoroughly using a ball mill to obtain modified nanoparticles;

[0041] The nanoparticles are nano-zinc oxide;

[0042] The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is 0.05:1.

[0043] The general formula for quaternary ammonium salt silane coupling agents is:

[0044] (R1)3Si-(CH2)nN + (R2)(R3)((CH2) m OCOCH=CH2)X -

[0045] Wherein, R1 is methoxy, and R2 and R3 are alkyl;

[0046] m and n are both 1;

[0047] X is Cl - .

[0048] During the ball milling process: the ball ratio is 10:1, the ball milling time is 1 hour, and the ball mill speed is 500 rpm.

[0049] The particle size of the nanoparticles is 50–200 nm.

[0050] In step 1, the mass ratio of softwood fiber, broadleaf fiber, and regenerated fiber is 5:1:0.8.

[0051] The fineness of the regenerated fiber is 1.2 to 1.5 dtex, and the length is 32 to 38 mm. The regenerated fiber is cotton-type regenerated cellulose short fiber.

[0052] The initiator is ammonium persulfate.

[0053] In step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is 30:1.

[0054] In Example 2, a fiber pretreatment method for dialysis paper includes the following steps:

[0055] Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture.

[0056] Step 2: Add the initiator to the mixture, heat to 45°C, and mix thoroughly;

[0057] Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 6 hours;

[0058] Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper;

[0059] The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is 0.005:1;

[0060] In step 3, the ratio of the total mass of the modified nanoparticles to the total mass of the fibers in step 1 is 0.06:1.

[0061] The preparation method of modified nanoparticles includes the following steps: mixing quaternary ammonium salt silane coupling agent with nanoparticles thoroughly using a ball mill to obtain modified nanoparticles;

[0062] The nanoparticles are nano-titanium oxide;

[0063] The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is 0.12:1.

[0064] The general formula for quaternary ammonium salt silane coupling agents is:

[0065] (R1)3Si-(CH2)nN + (R2)(R3)((CH2) m OCOCH=CH2)X -

[0066] Wherein, R1 is an ethoxy group, and R2 and R3 are alkyl groups;

[0067] m is 10, n is 8;

[0068] X is Br - .

[0069] During the ball milling process: the ball ratio is 20:1, the ball milling time is 2 hours, and the ball mill speed is 700 rpm.

[0070] The particle size of the nanoparticles is 50–200 nm.

[0071] In step 1, the mass ratio of softwood fiber, broadleaf fiber, and regenerated fiber is 6:1:1.2.

[0072] The fineness of the regenerated fiber is 1.2 to 1.5 dtex, and the length is 32 to 38 mm. The regenerated fiber is cotton-type regenerated cellulose short fiber.

[0073] The initiator is sodium persulfate.

[0074] In step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is 60:1.

[0075] In Example 3, a fiber pretreatment method for dialysis paper includes the following steps:

[0076] Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture.

[0077] Step 2: Add the initiator to the mixture, heat to 40°C, and mix thoroughly;

[0078] Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 5 hours;

[0079] Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper;

[0080] The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is 0.004:1;

[0081] In step 3, the ratio of the total mass of the modified nanoparticles to the total mass of the fibers in step 1 is 0.04:1.

[0082] The preparation method of modified nanoparticles includes the following steps: mixing quaternary ammonium salt silane coupling agent with nanoparticles thoroughly using a ball mill to obtain modified nanoparticles;

[0083] The nanoparticles are nano-alumina;

[0084] The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is 0.1:1.

[0085] The general formula for quaternary ammonium salt silane coupling agents is:

[0086] (R1)3Si-(CH2)nN + (R2)(R3)((CH2) m OCOCH=CH2)X -

[0087] Wherein, R1 is methoxy, and R2 and R3 are alkyl;

[0088] m is 4, n is 5;

[0089] X is Br - .

[0090] During the ball milling process: the ball ratio is 15:1, the ball milling time is 1.5 hours, and the ball mill speed is 600 rpm.

[0091] The particle size of the nanoparticles is 50–200 nm.

[0092] In step 1, the mass ratio of softwood fiber, broadleaf fiber, and regenerated fiber is 5.5:1:1.

[0093] The fineness of the regenerated fiber is 1.2 to 1.5 dtex, and the length is 32 to 38 mm. The regenerated fiber is cotton-type regenerated cellulose short fiber.

[0094] The initiator is ammonium persulfate.

[0095] In step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is 40:1.

[0096] In Example 4, a fiber pretreatment method for dialysis paper includes the following steps:

[0097] Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture.

[0098] Step 2: Add the initiator to the mixture, heat to 40°C, and mix thoroughly;

[0099] Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 5 hours;

[0100] Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper;

[0101] The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is 0.004:1;

[0102] In step 3, the ratio of the total mass of the modified nanoparticles to the total mass of the fibers in step 1 is 0.04:1.

[0103] The preparation method of modified nanoparticles includes the following steps: mixing quaternary ammonium salt silane coupling agent with nanoparticles thoroughly using a ball mill to obtain modified nanoparticles;

[0104] The nanoparticles are a mixture of nano-alumina and nano-zinc oxide in a mass ratio of 1:1;

[0105] The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is 0.1:1.

[0106] The general formula for quaternary ammonium salt silane coupling agents is:

[0107] (R1)3Si-(CH2)nN +(R2)(R3)((CH2) m OCOCH=CH2)X -

[0108] Wherein, R1 is an ethoxy group, and R2 and R3 are alkyl groups;

[0109] m is 6, n is 8;

[0110] X is Br - .

[0111] During the ball milling process: the ball ratio is 15:1, the ball milling time is 1.5 hours, and the ball mill speed is 600 rpm.

[0112] The particle size of the nanoparticles is 50–200 nm.

[0113] In step 1, the mass ratio of softwood fiber, broadleaf fiber, and regenerated fiber is 6:1:1.2.

[0114] The fineness of the regenerated fiber is 1.2 to 1.5 dtex, and the length is 32 to 38 mm. The regenerated fiber is cotton-type regenerated cellulose short fiber.

[0115] The initiator is ammonium persulfate.

[0116] In step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is 40:1.

[0117] In Example 5, a fiber pretreatment method for dialysis paper includes the following steps:

[0118] Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture.

[0119] Step 2: Add the initiator to the mixture, heat to 40°C, and mix thoroughly;

[0120] Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 5 hours;

[0121] Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper;

[0122] The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is 0.004:1;

[0123] In step 3, the ratio of the total mass of the modified nanoparticles to the total mass of the fibers in step 1 is 0.04:1.

[0124] The preparation method of modified nanoparticles includes the following steps: mixing quaternary ammonium salt silane coupling agent with nanoparticles thoroughly using a ball mill to obtain modified nanoparticles;

[0125] The nanoparticles are a mixture of nano-alumina and nano-titanium oxide in a mass ratio of 1:1;

[0126] The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is 0.1:1.

[0127] The general formula for quaternary ammonium salt silane coupling agents is:

[0128] (R1)3Si-(CH2)nN + (R2)(R3)((CH2) m OCOCH=CH2)X -

[0129] Wherein, R1 is methoxy, and R2 and R3 are alkyl;

[0130] m is 4, n is 5;

[0131] X is Br - .

[0132] During the ball milling process: the ball ratio is 15:1, the ball milling time is 1.5 hours, and the ball mill speed is 600 rpm.

[0133] The particle size of the nanoparticles is 50–200 nm.

[0134] In step 1, the mass ratio of softwood fiber, broadleaf fiber, and regenerated fiber is 5:1:0.8.

[0135] The fineness of the regenerated fiber is 1.2 to 1.5 dtex, and the length is 32 to 38 mm. The regenerated fiber is cotton-type regenerated cellulose short fiber.

[0136] The initiator is ammonium persulfate.

[0137] In step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is 40:1.

[0138] In Comparative Example 1, no initiator was added during the pretreatment process, unlike in Example 3, but the rest of the process was the same as in Example 3.

[0139] In Comparative Example 2, no modified nanoparticles were added during the pretreatment process compared to Example 3, while the rest of the process was the same as in Example 3.

[0140] In Comparative Example 3, compared with Example 3, an equal mass of nano-alumina was not added to replace the modified nanoparticles during the pretreatment process, and the rest was the same as in Example 3.

[0141] A dialysis paper, wherein the dialysis paper is prepared from fibers treated according to the above-described fiber pretreatment method for dialysis paper.

[0142] The fibers prepared in Examples 1-5 and Comparative Examples 1-3 were used to make dialysis paper, and their performance was tested. The tests included air permeability, water resistance, and maximum pore size. The test methods were carried out according to GB / T 2679.3-2023, the test method for water resistance was carried out according to GB / T 21332-2023, and the test method for maximum pore size was carried out according to GB / T 19633.1-2023. The test results are shown in Table 1.

[0143]

[0144] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A fiber pretreatment method for dialysis paper, characterized in that, Includes the following steps: Step 1: Weigh out the softwood fiber, broadwood fiber and regenerated fiber and put them into deionized water. Stir them thoroughly to obtain a mixture. Step 2: Add the initiator to the mixture, heat to 35-45℃, and mix thoroughly; Step 3: Add the modified nanoparticles to the mixture from Step 2 and stir continuously for 4 to 6 hours; Step 4: After the reaction is complete, wash, filter and dry to obtain pretreated fibers for dialysis paper; The ratio of the mass of the initiator in step 2 to the total mass of the fiber in step 1 is (0.003~0.005):1; The ratio of the modified nanoparticles in step 3 to the total mass of the fibers in step 1 is (0.02~0.06):

1.

2. The fiber pretreatment method for dialysis paper according to claim 1, characterized in that, The method for preparing the modified nanoparticles includes the following steps: mixing the quaternary ammonium salt silane coupling agent and the nanoparticles thoroughly using a ball mill to obtain the modified nanoparticles; The nanoparticles are one or more of nano zinc oxide, nano titanium oxide, and nano aluminum oxide. The mass ratio of quaternary ammonium salt silane coupling agent to nanoparticles is (0.05-0.12):

1.

3. The fiber pretreatment method for dialysis paper according to claim 2, characterized in that, The general formula of the quaternary ammonium salt silane coupling agent is: (R1)3Si-(CH2)n-N + (R2)(R3)((CH2) m OCOCH=CH2)X - Wherein, R1 is methoxy or ethoxy, and R2 and R3 are alkyl; m and n are integers greater than or equal to 1; X represents a halide anion.

4. The fiber pretreatment method for dialysis paper according to claim 2, characterized in that, During the ball milling process, the ball milling is carried out for 1 to 2 hours at a ball-to-material ratio of 10 to 20:1, and the ball mill speed is 500 to 700 rpm.

5. The fiber pretreatment method for dialysis paper according to claim 2, characterized in that, The nanoparticles have a particle size of 50–200 nm.

6. The fiber pretreatment method for dialysis paper according to claim 1, characterized in that, In step 1, the mass ratio of softwood fiber, broadwood fiber and regenerated fiber is (5-6):1:(0.8-1.2).

7. The fiber pretreatment method for dialysis paper according to claim 1, characterized in that, The regenerated fiber has a fineness of 1.2 to 1.5 dtex and a length of 32 to 38 mm, and the regenerated fiber is a cotton-type regenerated cellulose short fiber.

8. The fiber pretreatment method for dialysis paper according to claim 1, characterized in that, The initiator is either ammonium persulfate or sodium persulfate.

9. The fiber pretreatment method for dialysis paper according to claim 1, characterized in that, In step 1, the mass ratio of deionized water to the total mass of fibers in step 1 is (30-60):

1.

10. A dialysis paper, wherein the dialysis paper is prepared from fibers treated by the fiber pretreatment method for dialysis paper according to any one of claims 1 to 9.

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