CN111518280B

CN111518280B - Modified cellulose and application thereof

Info

Publication number: CN111518280B
Application number: CN202010362574.9A
Authority: CN
Inventors: 卢志敏; 陈武渊; 罗锐; 蔡熙扬; 陆业昌; 潘宇鹏; 杨智春; 郭晓丹; 黄煜璇
Original assignee: Guangzhou Lonkey Industrial Co ltd
Current assignee: Guangzhou Langqi Daily Necessities Co ltd
Priority date: 2020-04-30
Filing date: 2020-04-30
Publication date: 2022-04-08
Anticipated expiration: 2040-04-30
Also published as: CN111518280A

Abstract

The invention discloses modified cellulose and application thereof. Wherein the modified cellulose is prepared by the following steps: oxidizing cellulose into 2, 3-dicarboxyl cellulose, and carrying out condensation reaction on the 2, 3-dicarboxyl cellulose and (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone under the action of heating and a dehydrating agent to obtain the modified cellulose. The modified cellulose related to the invention is applied to fabric washing, color absorbing and dye preventing, and can also effectively resist microorganisms.

Description

Modified cellulose and application thereof

Technical Field

The invention belongs to the field of textile engineering, and particularly relates to modified cellulose and application thereof.

Background

In the washing process of daily-worn fabrics, dyes on the surfaces of the fabrics fall off and enter a washing solution, and are transferred to the surfaces of other fabrics washed simultaneously along with the stirring of the washing operation, so that the color cross phenomenon seen by naked eyes is caused.

Currently, color absorbing sheets with a color cross-linking prevention function have been developed in the industry to avoid the phenomenon of color cross-linking of fabrics during shuffling. Chinese patent application CN103132276A discloses a viscose nonwoven fabric modified with 2, 3-epoxypropyltrimethylammonium chloride; chinese patent application CN106319760A discloses a nonwoven fabric made of anion modified fiber and cation modified fiber; chinese patent application CN 107474178A discloses an acrylate copolymer containing a cationic monomer copolymer. The core idea of the above patent application is that a water-insoluble substrate is loaded with charged ionic groups, and free dye molecules with opposite charges are adsorbed on the substrate through electrostatic adsorption, so that the dye molecules cannot move freely in the washing process, and the cross-color phenomenon cannot be caused.

However, the imbibition film based on this idea has two serious drawbacks: firstly, in the actual washing process, the distance between the fabrics is very small, even the surfaces of the fabrics are often tightly attached, and the electrostatic adsorption attached in the above thought is a passive adsorption method, which is like the function of a filter screen, can only adsorb dye molecules passing through the color absorbing sheet, but cannot effectively adsorb the dye molecules far away from the color absorbing sheet; therefore, the dye falling off from the fabric is often dyed on the fabric at a closer distance before being absorbed by the color absorbing sheet. Secondly, detergent is usually required to be added in the washing process to improve the effect of washing stains, the detergent often contains a large amount of anionic surfactant and sometimes also contains a small amount of cationic surfactant, and the ionic surfactants can be strongly adsorbed by the color absorbing sheet. When the color absorbing sheet absorbs the surfactant instead of the target dye, the color absorbing capacity of the color absorbing sheet is reduced, and the color cross-color preventing effect of the color absorbing sheet is reduced. In addition, the color absorbing sheet absorbs the surfactant, so that the concentration of effective substances of the detergent is reduced, and the decontamination effect of the detergent is also reduced. Thirdly, the existing color absorbing fiber is a physical absorption fiber which dissolves and absorbs the dye trapping agent on the non-woven fabric, and the dye trapping agent generates friction loss part in the production, packaging and use processes, thereby influencing the product effect.

The anti-cross-color material in the current market can only play a role in preventing cross-color, and has a single effect, so that the anti-cross-color material which can better prevent cross-color and has a better antibacterial effect is required to be prepared.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention provides a modified cellulose which can be applied to fabric washing, color absorption and dye prevention and is also effective in resisting microorganisms.

The technical purpose of the invention is realized by the following technical scheme:

the modified cellulose is prepared by the following steps: oxidizing cellulose into 2, 3-dicarboxyl cellulose, and carrying out condensation reaction on the 2, 3-dicarboxyl cellulose and (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone under the action of heating and a dehydrating agent to obtain the modified cellulose.

Further, the mass ratio of the (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone to the 2, 3-dicarboxy cellulose ranges from (1:9) to (6:4), and the amount of the dehydrating agent used in the reaction is 3-8% of the total mass of the 2, 3-dicarboxy cellulose and the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone; preferably, the dehydrating agent is selected from phosphorus pentoxide, acetic anhydride, acetyl chloride or phosphorus oxychloride; preferably, the heating temperature range is 50-65 ℃.

Further, the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone of the present invention is prepared by the following method: performing polymerization reaction on vinyl pyrrolidone aqueous solution under the action of a catalyst and an initiator, adding (4-vinylphenyl-4' -methylene carboxyl phenyl) iodonium, sealing, and drying to obtain the catalyst.

Furthermore, the mass ratio of the vinyl pyrrolidone aqueous solution, the catalyst and the initiator to the 4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is 100: (0.2-0.5): (0.3-0.6): (0.5 to 2); preferably, the catalyst is hydrogen peroxide; preferably, the initiator is azobisisobutyronitrile.

Further, the temperature of the polymerization reaction of the vinyl pyrrolidone aqueous solution, the catalyst and the initiator is 40-80 ℃, and the reaction time is 2-5 h; preferably, the reaction time is 0.2-0.8 h after the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is added; preferably, after the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone is obtained, 0.2-0.6 mass percent of ammonia water is added into the polymer; preferably, the drying is spray drying, and the hot air temperature range of the spray drying is 120-180 ℃.

Further, the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium of the present invention is prepared by the following method: the diphenyl iodonium salt reacts with ethylene under the action of a molecular sieve catalyst to obtain 4,4 '-divinyl diphenyl iodonium, and the 4-vinyl phenyl-4' -methylene carboxyl phenyl) iodonium is obtained through catalyst oxidation.

Furthermore, the mass ratio of the diphenyl iodonium salt to the ethylene is (7:1) - (9:1), and the dosage of the molecular sieve catalyst is 0.05-0.2% of the mass of the ethylene; preferably, the reaction pressure is 0.8-2.0 MPa, and the reaction temperature is 120-220 ℃; preferably, the molecular sieve catalyst is selected from a magnesium, calcium or barium exchanged sodium ZSM-5 type molecular sieves.

Further, the catalyst used for oxidizing 4,4' -divinyldiphenyliodonium according to the present invention is a supported palladium (Pd) heteropoly acid (hetetopolyacid) catalyst; preferably, the amount of the catalyst is 0.02-0.1% of the mass of 4,4' -divinyl diphenyl iodonium; preferably, the reaction temperature is 140-260 ℃ and the reaction pressure is 0.3-1.5 MPa.

Further, the 2, 3-dicarboxyl cellulose is prepared by the following method:

1) dialdehyde cellulose: sodium acetate and HIO for cellulose₄Oxidation is carried out at the reaction temperatureThe reaction time is 40-60 h at 35-45 ℃;

2) 2, 3-dicarboxylcellulose: dripping acidic potassium permanganate solution (5% aqueous solution) into dialdehyde cellulose at 50 + -3 deg.C until the acid potassium permanganate does not fade, recrystallizing, and drying.

Further, the concentration range of the sodium acetate is preferably 0.03-0.08 g/mL, and the HIO is preferably₄The concentration range of (A) is 0.08-0.2 g/mL; preferably, the concentration of the cellulose is 0.03-0.06 g/mL; preferably, the cellulose is soaked in a methanol-water solution with the mass ratio of 0.2-5 for 2-6 h.

Further, the cellulose of the present invention is selected from natural cellulose and/or regenerated cellulose.

The invention also aims to provide the application of the modified cellulose in fabric washing, color absorbing and dye preventing.

The invention adopts the technical scheme to achieve the following beneficial effects:

1. the existing color-absorbing fiber is characterized in that a dye trapping agent is dissolved and adsorbed on non-woven fabric, the non-woven fabric is not chemically modified, the non-woven fabric is physically adsorbed, and the product effect is influenced by the dye trapping agent at the friction loss part generated in the processes of production, packaging and use.

2. The existing color absorbing fiber only has the function of absorbing dye, has single function, does not have the antibacterial and bacteriostatic effects, cannot meet the requirement of consumers on playing multiple effects by one-time washing, and can take the effects of absorbing dye and inhibiting bacteria on clothes into consideration.

3. The existing dye capture agent is a cationic surfactant which is incompatible with an anionic surfactant in a detergent, and the anionic surfactant is dominant in the washing process, so that the cationic surfactant and the anionic surfactant are directly dissolved in a system to form a salt, the consumed anionic surfactant influences the detergency, and the reacted cationic surfactant loses the capability of capturing the dye. The modified cellulose adopted by the invention is hydrolyzed when clothes are washed, the (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone is dissociated again, the polyvinylpyrrolidone is an efficient dye capture agent, the iodonium compound is a cationic surfactant, and can be compatible with an anionic surfactant, and the effective antibacterial effect can still be exerted in the washing process.

Detailed Description

The present invention will be described in more detail with reference to specific preferred embodiments, but the present invention is not limited to the following embodiments.

Preparation of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium the supported palladium (Pd) heteropolyacid (heteropolyacid) catalyst may be selected from the national distributors company, the StandoilCo, USA, Halcon International Inc, France institute Francasdu Petrol, Japan catalytic industry or Japan Showa and electrician.

The diphenyliodonium salt used in the preparation of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium can be selected from the group consisting of Shanghai-sourced Biotech Co., Ltd, Shanghai Henfei Biotech Co., Ltd, Shanghai-Yoghei Biotech Co., Ltd, Shanghai-minghai-Biotech Co., Ltd and the like, having CAS number 722-56-5 (including, but not limited to, the above-mentioned companies), which are not listed herein.

Preparation of mono- (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium

1. The method comprises the following steps of (1) reacting diphenyl iodonium salt with ethylene by using a molecular sieve as a catalyst to obtain 4,4' -divinyl diphenyl iodonium (shown in a formula (I) (the reaction conditions of examples 1-1, 1-2 and 1-3 are shown in a table 1), and partially oxidizing the 4,4' -divinyl diphenyl iodonium with a supported palladium (Pd) heteropoly acid (hetetopolyacid) catalyst system to obtain 4-vinylphenyl-4 ' -methylene carboxyl phenyl) iodonium (shown in a formula (II)) (the reaction conditions of examples 1-1, 1-2 and 1-3 are shown in a table 2):

wherein the molecular sieve is selected from sodium ZSM-5 type molecular sieve exchanged by magnesium, calcium or barium.

TABLE 1 reaction conditions and material amounts of diphenyliodonium salts with ethylene

TABLE 24,4' -Divinyldiphenyliodonium partial catalytic Oxidation conditions and amounts of materials

Examples	Catalyst proportion/%)	Kind of catalyst	Reaction pressure/MPa	Reaction temperature/. degree.C
					1-1	0.02	Pd-H₃PO₄-Au/Al₂O₃	0.3～0.5	140～160
1-2	0.05	PdO/V₂O₅/Sb₂O₃/Al₂O₃	0.8～1.0	230～260
					1-3	0.1	Pd/V₂O₅	1.0～1.2	200～220

Secondly, preparing modified cellulose

Example 2-1

1. Synthesis of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone

Preparing a monomer vinyl pyrrolidone (NVP) into an aqueous solution with the mass fraction of 45%, using a small amount of hydrogen peroxide (0.2% of NVP) as a catalyst, and initiating polymerization at 40-50 ℃ under the action of azobisisobutyronitrile (0.3% of NVP), wherein the reaction time is 2 hours, and the monomer polymerization conversion rate is 93-95%. (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium obtained in example 1-1 (NVP in an amount of 0.5%) was added and reacted for 0.2 hour to terminate the polymer, thereby obtaining (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone.

0.2% ammonia was added to the polymer to decompose the remaining azobisisobutyronitrile. The polymer was spray dried with 120-135 ℃ hot air to obtain powdery (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone. The (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium capping rate is 80 to 85%.

The synthesis reaction of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone is as follows:

2. synthesis of 2, 3-dicarboxy cellulose

Soaking cellulose in methanol-water solution (1:5) for 2 hr, and soaking in HIO₄Carrying out oxidation, wherein the concentration of each substance in a reaction system is as follows: sodium acetate 0.03g/mL, HIO₄The concentration is 0.08g/mL, the cellulose concentration is 0.03g/mL, the reaction temperature is 35-40 ℃, and the reaction time is 40 h. Reacting to obtain dialdehyde cellulose. Slowly dripping an acidic potassium permanganate solution (5% aqueous solution) into the dialdehyde cellulose at the temperature of 50 ℃ until the acid potassium permanganate does not fade, and obtaining the 2, 3-dicarboxy cellulose. Adding methanol into 2, 3-dicarboxyl cellulose for recrystallization, and vacuum drying at 50 ℃. The carboxylic acid group content was 45%.

The synthesis reaction of 2, 3-dicarboxy cellulose is shown as the following formula (IV):

3. synthesis of modified cellulose

Heating (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose (the mass ratio is 1:9) to 50-55 ℃ under the action of phosphorus pentoxide (the dosage is 3% of the total mass of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose), and carrying out intermolecular dehydration reaction, wherein the carboxyl of (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and the carboxyl of 2, 3-dicarboxyl cellulose are subjected to condensation reaction, so as to obtain the modified cellulose. The condensation rate of the carboxyl group of the 2, 3-biscarboxylcellulose was 75%. The reaction equation is shown as formula (V):

examples 2 to 2

The monomer vinyl pyrrolidone (NVP) is prepared into an aqueous solution with the mass fraction of 50%. A small amount of hydrogen peroxide (NVP with the dosage of 0.3%) is used as a catalyst, polymerization is initiated at 50-60 ℃ under the action of azobisisobutyronitrile (NVP with the dosage of 0.4%) for 3 hours, the monomer polymerization conversion rate is 96-98%, ((4-vinylphenyl-4-methylenecarboxyphenyl) iodonium (NVP with the dosage of 0.8%) prepared in example 1-1 is added, and the reaction is carried out for 0.5 hour, so that the polymer is terminated, and the (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone is obtained.

0.3% ammonia was added to the polymer to decompose the remaining azobisisobutyronitrile. The polymer is spray dried under the hot air of 135-150 ℃ to obtain the powdery (4-vinyl phenyl-4-methylene carboxyl phenyl) iodonium terminated polyvinylpyrrolidone. The reaction equation of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium capping ratio is 85 to 90%, which is shown by the formula (IV) in example 2-1.

2. Synthesis of 2, 3-dicarboxy cellulose

Soaking cellulose in methanol-water solution (1:1) for 4 hr, and soaking in HIO₄Oxidation is carried out. The concentration of each substance in the reaction system is as follows: sodium acetate 0.05g/mL, HIO₄The concentration is 0.1g/mL, the cellulose concentration is 0.04g/mL, the reaction temperature is 40-45 ℃, and the reaction time is 50 h. Reacting to obtain dialdehyde cellulose. Slowly dripping an acidic potassium permanganate solution (5% aqueous solution) into the dialdehyde cellulose at the temperature of 55 ℃ until the acid potassium permanganate does not fade, and obtaining the 2, 3-dicarboxy cellulose. Adding methanol into the 2, 3-dicarboxyl cellulose for recrystallization, and drying in vacuum at 60 ℃. The carboxylic acid group content was 50%. Reaction equation of the reaction scheme example 2-1 is represented by the formula (III)

3. Synthesis of modified cellulose

Heating (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose (the mass ratio is 6:4) to 58-60 ℃ under the action of acetic anhydride (the dosage is 4% of the total mass of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose), and carrying out intermolecular dehydration reaction, and carrying out condensation reaction on carboxyl of (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and carboxyl of 2, 3-dicarboxyl cellulose to obtain the modified cellulose. The condensation rate of the carboxyl group of the 2, 3-biscarboxylcellulose was 80%. The reaction equation is shown in formula (V) of example 2-1.

Examples 2 to 3

The monomer vinylpyrrolidone (NVP) was prepared as an aqueous solution with a mass fraction of 55%. A small amount of hydrogen peroxide (0.4% of NVP) is used as a catalyst, polymerization is initiated at 60-70 ℃ under the action of azobisisobutyronitrile (0.5% of NVP), the reaction is carried out for 4 hours, and the monomer polymerization conversion rate is 97-99%. (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium obtained in example 1-2 (NVP in an amount of 1%) was added and reacted for 0.6 hour to terminate the polymer and obtain (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone.

0.4% ammonia was added to the polymer to decompose the remaining azobisisobutyronitrile. The polymer was spray dried with hot air at 150-165 ℃ to obtain powdery (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone. The reaction equation is shown in formula (III) of example 2-1, wherein the capping rate of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is 90 to 93%.

2. Synthesis of 2, 3-dicarboxy cellulose

Soaking cellulose in methanol-water solution (3:1) for 5 hr, and soaking in HIO₄Oxidation is carried out. The concentration of each substance in the reaction system is as follows: sodium acetate 0.06g/mL, HIO₄The concentration is 0.15g/mL, the cellulose concentration is 0.05g/mL, the reaction temperature is 35-40 ℃, and the reaction time is 50 h. Reacting to obtain dialdehyde cellulose. Slowly dripping an acidic potassium permanganate solution (5% aqueous solution) into the dialdehyde cellulose at the temperature of 45 ℃ until the acid potassium permanganate does not fade, and obtaining the 2, 3-dicarboxy cellulose. Adding methanol into 2, 3-dicarboxyl cellulose for recrystallization, and vacuum drying at 70 ℃. The carboxylic acid group content was 55%. The reaction equation is shown in formula (IV) of example 2-1.

3. Synthesis of modified cellulose

Heating (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose (the mass ratio is 1:1) to 55-60 ℃ under the action of acetyl chloride (the dosage is 5% of the total mass of the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and the 2, 3-dicarboxyl cellulose), and carrying out intermolecular dehydration reaction, and carrying out condensation reaction on carboxyl of the (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and carboxyl of the 2, 3-dicarboxyl cellulose to obtain the modified cellulose. The condensation rate of the carboxyl group of the 2, 3-biscarboxylcellulose was 85%. The reaction equation is shown in formula (V) of example 2-1.

Examples 2 to 4

The monomer vinyl pyrrolidone (NVP) is prepared into an aqueous solution with the mass fraction of 50%. A small amount of hydrogen peroxide (0.5% of NVP) is used as a catalyst, polymerization is initiated at 70-80 ℃ under the action of azobisisobutyronitrile (0.6% of NVP), the reaction is carried out for 5 hours, and the monomer polymerization conversion rate is 98-99%. (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium obtained in examples 1 to 3 (NVP in an amount of 2%) was added and reacted for 0.8 hour to terminate the polymer, thereby obtaining (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone.

0.6% ammonia was added to the polymer to decompose the remaining azobisisobutyronitrile. The polymer was spray dried with hot air at 165-180 ℃ to obtain powdery (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone. The reaction equation is shown in formula (III) of example 2-1, wherein the capping rate of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is 93-95%.

2. Synthesis of 2, 3-dicarboxy cellulose

Soaking cellulose in methanol-water solution (5:1) for 6 hr, and soaking in HIO₄Oxidation is carried out. The concentration of each substance in the reaction system is as follows: sodium acetate 0.08g/mL, HIO₄The concentration is 0.2g/mL, the cellulose concentration is 0.06g/mL, the reaction temperature is 40-45 ℃, and the reaction time is 60 h. Reacting to obtain dialdehyde cellulose. Slowly dripping an acidic potassium permanganate solution (5% aqueous solution) into the dialdehyde cellulose at the temperature of 55 ℃ until the acid potassium permanganate does not fade, and obtaining the 2, 3-dicarboxy cellulose. Adding methanol into 2, 3-dicarboxyl cellulose for recrystallization, and vacuum drying at 80 ℃. The carboxylic acid group content was 48%. The reaction equation is shown in formula (IV) of example 2-1.

3. Synthesis of modified cellulose

Heating (4-vinylphenyl-4-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose (the mass ratio is 1:5) to 60-65 ℃ under the action of phosphorus oxychloride (the dosage is 4% of the total mass of (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and 2, 3-dicarboxyl cellulose), and carrying out intermolecular dehydration reaction, wherein the carboxyl of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone and the carboxyl of 2, 3-dicarboxyl cellulose are subjected to condensation reaction, so as to obtain the modified cellulose. The condensation rate of the carboxyl group of the 2, 3-biscarboxylcellulose was 82%. The reaction equation is shown in formula (V) of example 2-1.

Third, effect test

1. Test of color absorption Effect

A standard curve of the dye was made at the wavelength of maximum absorbance of the dye. The mass of the color-absorbing fiber is 0.5g, the color-absorbing fiber is placed into 1L of dye solution with the concentration of 150ppm, the mixture is stirred for 5 minutes, the absorbance of the dye solution before and after the test is measured, the corresponding dye concentration is obtained by checking a standard curve, and the adsorption rate of the dye is obtained by calculation, as shown in Table 3.

TABLE 3 comparison of color-absorbing effects of modified celluloses of examples 2-1 to 2-4 and comparative examples 1 to 2

As is clear from the color absorption comparison in Table 3, the modified celluloses of examples 2-1 to 2-4 have significant dye adsorption effect, the dye adsorption rate exceeds the commercially available color absorption sheet by 15% or more, and the ordinary commercially available cotton fiber nonwoven fabric has almost no color absorption effect.

2. Test of antibacterial Effect

Refer to QB/T2738 and 2012 evaluation on antibacterial and bacteriostatic effects of daily chemical products 7.3. 1g of the color absorbing fiber is soaked in 100g of deionized water for 10 minutes, and the soaked solution is taken as a test sample solution to directly carry out a bacteriostasis test. The bacteriostatic ratio of the color-absorbing fiber was calculated as shown in table 4.

TABLE 4 comparison of the bacteriostatic effects of modified celluloses of examples 2-1 to 2-4 and comparative examples 1 to 2

As can be seen from the comparison of the bacteriostatic effects in table 4, the modified cellulose in examples 2-1 to 2-4 has significant bacteriostatic effects on four strains, namely staphylococcus aureus, escherichia coli, pseudomonas aeruginosa, and candida albicans (as specified in QB/T2738-2012, "evaluation of antibacterial and bacteriostatic effects for daily chemical products", the bacteriostatic rate is greater than or equal to 50% and the bacteriostatic effect is not observed on the common cotton fiber nonwoven fabric and the commercially available color absorbing sheet).

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, so that any simple modification, equivalent change and modification made to the above embodiment according to the technical spirit of the present invention are within the scope of the technical solution of the present invention.

Claims

1. The modified cellulose is characterized by being prepared by the following steps: oxidizing cellulose into 2, 3-dicarboxyl cellulose, and carrying out condensation reaction on the 2, 3-dicarboxyl cellulose and (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone under the action of heating and a dehydrating agent to obtain the modified cellulose.

2. The modified cellulose according to claim 1, wherein the mass ratio of the (4-vinylphenyl-4 '-methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone to the 2, 3-biscarboxy cellulose is (1:9) to (6:4), and the amount of the dehydrating agent is 3 to 8% of the total mass of the 2, 3-biscarboxy cellulose and the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone.

3. The modified cellulose according to claim 2, wherein the dehydrating agent is selected from phosphorus pentoxide, acetic anhydride, acetyl chloride or phosphorus oxychloride.

4. The modified cellulose according to claim 2, wherein the heating temperature is in the range of 50 to 65 ℃.

5. The modified cellulose of claim 1, wherein the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium terminated polyvinylpyrrolidone is prepared by a process comprising: performing polymerization reaction on vinyl pyrrolidone aqueous solution under the action of a catalyst and an initiator, adding (4-vinylphenyl-4' -methylene carboxyl phenyl) iodonium, sealing, and drying to obtain the catalyst.

6. The modified cellulose according to claim 5, wherein the mass ratio of the vinylpyrrolidone aqueous solution, the catalyst, the initiator and the 4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is 100: (0.2-0.5): (0.3-0.6): (0.5-2).

7. The modified cellulose of claim 6, wherein the catalyst is hydrogen peroxide.

8. The modified cellulose of claim 6, wherein said initiator is azobisisobutyronitrile.

9. The modified cellulose according to claim 5, wherein the temperature of the polymerization reaction of the vinyl pyrrolidone aqueous solution, the catalyst and the initiator is 40-80 ℃ and the reaction time is 2-5 h.

10. The modified cellulose according to claim 9, wherein the reaction time after addition of (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is 0.2 to 0.8 h.

11. The modified cellulose according to claim 9, wherein after the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium-terminated polyvinylpyrrolidone is obtained, 0.2 to 0.6 mass% of aqueous ammonia is added to the polymer.

12. The modified cellulose according to claim 9, wherein the drying is spray drying with hot air temperature ranging from 120 to 180 ℃.

13. The modified cellulose according to claim 5, wherein the (4-vinylphenyl-4' -methylenecarboxyphenyl) iodonium is prepared by: the diphenyl iodonium salt reacts with ethylene under the action of a molecular sieve catalyst to obtain 4,4 '-divinyl diphenyl iodonium, and then (4-vinyl phenyl-4' -methylene carboxyl phenyl) iodonium is obtained through catalyst oxidation.

14. The modified cellulose according to claim 13, wherein the mass ratio of the diphenyliodonium salt to ethylene is (7:1) - (9:1), and the amount of the molecular sieve catalyst is 0.05-0.2% by mass of ethylene.

15. The modified cellulose according to claim 14, wherein the reaction pressure is 0.8 to 2.0MPa and the reaction temperature is 120 to 220 ℃.

16. The modified cellulose of claim 14, wherein the molecular sieve catalyst is selected from a magnesium, calcium or barium exchanged sodium ZSM-5 type molecular sieve.

17. The modified cellulose of claim 13, wherein the catalyst used for the oxidation of 4,4' -divinyldiphenyliodonium is a supported palladium heteropolyacid catalyst.

18. The modified cellulose according to claim 17, wherein the amount of the catalyst is 0.02 to 0.1% by mass based on 4,4' -divinyldiphenyliodonium.

19. The modified cellulose according to claim 17, wherein the 4,4' -divinyldiphenyliodonium is oxidized at a temperature of 140 to 260 ℃ and a reaction pressure of 0.3 to 1.5 MPa.

20. The modified cellulose of claim 1, wherein the 2, 3-dicarboxylcellulose is prepared by the following method:

1) dialdehyde cellulose: sodium acetate and HIO for cellulose₄Oxidizing at 35-45 ℃ for 40-60 h;

2) 2, 3-dicarboxylcellulose: dripping 5% aqueous solution of acid potassium permanganate solution into dialdehyde cellulose at 50 + -3 deg.C until acid potassium permanganate does not fade, recrystallizing, and drying.

21. The modified cellulose of claim 20, wherein the concentration of sodium acetate is in the range of 0.03 to 0.08 g/mL.

22. The modified cellulose of claim 21, wherein the HIO is in the form of a HIO₄The concentration range of (b) is 0.08-0.2 g/mL.

23. The modified cellulose according to claim 21, wherein the concentration of the cellulose is 0.03 to 0.06 g/mL.

24. The modified cellulose according to claim 21, wherein the cellulose is soaked in a methanol-water solution at a mass ratio of 0.2 to 5 for 2 to 6 hours.

25. Modified cellulose according to claim 1, characterized in that the cellulose is selected from natural cellulose and/or regenerated cellulose.

26. Use of the modified cellulose as claimed in any one of claims 1 to 25 in the color-absorbing and dye-proofing of fabric washing.