Cellulose-based polymeric dye and preparation method thereof

Abstract

The invention provides a cellulose-based polymeric dye and a preparation method thereof. The preparation method of the cellulose-based polymeric dye comprises the following steps: adding a cotton fabric into a mixed solvent containing an inorganic base, urea and water, stirring to obtain a cellulose solution, adding a reactive dye into the cellulose solution, and reacting; the cellulose and the dye are dissolved through a homogeneous system, so that the hydroxyl activity of the cellulose and the dispersity and adsorbability of the dye can be improved, high loading of a dye chromophore on a cellulose polymer skeleton is realized, and the problems of low dye utilization rate, easiness in dye hydrolysis, water consumption, salt consumption and the like in the dyeing process are solved; the method is of great significance to improvement of economic benefits and sustainable development of the printing and dyeing industry.

Description

Technical Field

[0001] The invention belongs to the technical field of textile product printing and dyeing, and in particular relates to a cellulose-based polymer dye and a preparation method thereof. Background Art

[0002] Compared with small molecule dyes, polymer dyes contain multiple and / or multiple groups in their molecular structure and have long molecular chains. During the dyeing process, they can form multiple interactions with fibers, stably connect to fibers and avoid loss, and are expected to achieve a 100% fixation rate. In addition, by adjusting the type of polymer and the type and number of groups on the polymer, the compatibility of dyes and fibers can be increased, and the use of salt can be avoided or reduced. Cellulose is one of the most abundant natural polymers in nature. It contains a large number of reactive hydroxyl active groups, which provides cellulose with good chemical reactivity. Small molecule chromophores can be connected to the natural cellulose polymer skeleton to construct green, environmentally friendly, and environmentally friendly bio-based polymer dyes. Compared with traditional synthetic polymer dyes, cellulose-based polymer dyes have the advantages of good biodegradability, biocompatibility, and renewability. At present, the development and application of cellulose-based polymer dyes are still in their infancy. They are mainly based on nanocellulose and are prepared by heterogeneous salt-promoted dyeing and alkali fixation processes. There are problems such as low dye utilization, easy hydrolysis of dyes, and water and salt consumption. In addition, the modification of cellulose by dye chromophores usually occurs in the accessible region of cellulose. However, the accessible region of high-crystalline cellulose is small, which leads to the generally low loading of dye chromophores on cellulose-based polymer dyes.

[0003] Therefore, developing a polymer dye with a high loading of dye chromophore on a cellulose polymer skeleton is of great significance for solving the environmental pollution problem in the printing and dyeing process and promoting the progress of polymer dyeing technology. Summary of the invention

[0004] In view of this, the present invention proposes a cellulose-based polymer dye with a high-loaded dye color body and a preparation method thereof to solve the technical problems existing in the prior art.

[0005] In a first aspect, the present invention provides a method for preparing a cellulose-based polymer dye, comprising the following steps:

[0006] Adding cotton fabric into a mixed solvent containing an inorganic base, urea and water, stirring, and obtaining a cellulose solution;

[0007] adding a reactive dye into a cellulose solution to react;

[0008] The cellulose solution after the reaction is added into water to regenerate and precipitate, and separated to obtain a crude product, and the crude product is washed and dried to obtain a cellulose-based polymer dye.

[0009] Preferably, the inorganic base comprises LiOH and / or NaOH;

[0010] And / or, the reactive dye includes at least one of reactive blue 19, reactive orange 16, reactive blue 4, reactive red 158, reactive red 120, reactive red 195, and reactive black 5.

[0011] Preferably, a reactive dye is added to a cellulose solution, and then an organic base is added to react;

[0012] Wherein, the organic base includes at least one of DBU, DBN, betaine, choline chloride, trimethylamine and triethylamine.

[0013] Preferably, in the step of adding the cotton fabric to a mixed solvent containing an inorganic base, urea and water, the mass ratio of the inorganic base, urea and water is (5-15):(6-12):(70-90);

[0014] The mass ratio of cotton fabric to mixed solvent is (0.5-2):(5-15).

[0015] Preferably, in the step of adding the reactive dye to the cellulose solution, the concentration of the reactive dye is 5 to 200% owf.

[0016] Preferably, in the step of adding the reactive dye to the cellulose solution to react, or in the step of adding the reactive dye to the cellulose solution and then adding the organic base to react, the reaction temperature is 20-70° C. and the reaction time is 30-180 min.

[0017] Preferably, the mixed solvent containing inorganic alkali, urea and water is cooled to -5 to -12°C, and then the cotton fabric is added to the cooled mixed solvent and stirred to dissolve the cellulose in the cotton fabric to obtain a cellulose solution.

[0018] Preferably, the organic base is added in an amount of 1 to 20% by mass of the cotton fabric.

[0019] Preferably, the method comprises the following steps:

[0020] The mixed solvent containing inorganic base, urea and water is cooled to -5 to -12°C, and then cotton fabric is added to the cooled mixed solvent, and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution; wherein the inorganic base is LiOH or NaOH, and the mass ratio of the inorganic base, urea and water is 11:9:80;

[0021] Add the reactive dye to the cellulose solution, raise the temperature to 20-60°C at a heating rate of 1-3°C / min, and react for 30-150 minutes;

[0022] The cellulose solution after the reaction is put into water for regeneration and precipitation, and separated to obtain a crude product. The crude product is washed and dried to obtain a cellulose-based polymer dye.

[0023] In a second aspect, the present invention further provides a cellulose-based polymer dye, which is prepared by the preparation method.

[0024] The cellulose-based polymer dye and its preparation method of the present invention have the following advantages over the prior art:

[0025] Beneficial effects:

[0026] The preparation method of the cellulose-based polymer dye of the present invention improves the reaction efficiency of cellulose and active dyes through a homogeneous system, and constructs a cellulose-based polymer dye with a high-load dye chromophore. Cellulose is one of the most abundant natural polymers in nature and contains a large number of reactive hydroxyl active groups. Under alkaline conditions, the cellulose hydroxyl groups are activated and covalently bonded with the active dyes. The bonding force is irreversible in most cases, so that the color fastness is greatly improved. Since the cellulose hydroxyl groups have excellent reaction activity in the homogeneous system, more reaction sites are provided for the modification of the active dyes on the cellulose skeleton, which is beneficial to the fixation of the dye chromophore. The cellulose-based polymer dye prepared with cellulose as the raw material not only has the characteristics of processability, biodegradability, biocompatibility and renewability of cellulose polymer materials, but also inherits the color performance and coloring ability of small molecule chromophores, and is a high-performance coloring material. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In order to better understand the present invention but not to limit the scope of the present invention, all the numbers used in this application to express the amount, percentage, and other numerical values ​​should be understood as modified by the word "about" in all cases. Therefore, unless otherwise specified, the numerical parameters listed in the specification and the appended claims are approximate values, which may be changed according to the different ideal properties attempted to be obtained. Each numerical parameter should at least be regarded as obtained based on the reported significant figures and by conventional rounding methods.

[0029] It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments. In addition, in the description of the present application, the term "including" means "including but not limited to". Various embodiments of the present invention may be in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the numbered range, such as 1, 2, 3, 4, 5 and 6, which applies regardless of the range. In addition, whenever a numerical range is indicated in this article, it is meant to include any cited numbers (fractions or integers) within the indicated range.

[0030] The present invention provides a method for preparing a cellulose-based polymer dye, comprising the following steps:

[0031] S1, adding cotton fabric into a mixed solvent containing an inorganic base, urea and water, stirring, and obtaining a cellulose solution;

[0032] S2, adding the reactive dye to the cellulose solution to react;

[0033] S3, adding the reacted cellulose solution into water to regenerate and precipitate, separating to obtain a crude product, washing the crude product, and drying to obtain a cellulose-based polymer dye.

[0034] The preparation method of the cellulose-based polymer dye of the present invention, the main component of the cotton fabric (i.e., cotton fiber fabric) is cellulose; the cotton fabric is added to a mixed solvent containing an inorganic alkali, urea, and water, stirred to obtain a cellulose solution, and a reactive dye is added to the cellulose solution to react; the cellulose and the dye are dissolved by a homogeneous system, the activity of the cellulose hydroxyl group, the dispersibility and adsorption of the dye can be improved, and the high loading of the dye color body on the cellulose polymer skeleton is achieved, and the problems of low dye utilization rate, easy hydrolysis of the dye, and water and salt consumption in the dyeing process are solved, which is of great significance to improving the economic benefits and sustainable development of the printing and dyeing industry. The present invention prepares the cellulose-based polymer dye by a homogeneous system, and can solve the problems of poor levelness and poor color fastness in the dyeing process while ensuring a high dye color body loading amount, eliminating complex dyeing processes, improving subsequent dyeing effects, and significantly reducing printing and dyeing costs and wastewater treatment difficulties.

[0035] The invention improves the reaction efficiency of cellulose and reactive dyes through a homogeneous system, and constructs a cellulose-based polymer dye with a high-load dye chromophore. Cellulose is one of the most abundant natural polymers in nature, and contains a large number of reactive hydroxyl reactive groups. Under alkaline conditions, the cellulose hydroxyl groups are activated and covalently bonded with the reactive dyes. This bonding force is irreversible in most cases, so that the color fastness is greatly improved. Since the cellulose hydroxyl groups have excellent reaction activity in the homogeneous system, more reaction sites are provided for the modification of the reactive dyes on the cellulose skeleton, which is beneficial to the fixation of the dye chromophore. The cellulose-based polymer dye prepared with cellulose as a raw material not only has the characteristics of processability, biodegradability, biocompatibility and renewability of cellulose polymer materials, but also inherits the color performance and coloring ability of small molecule chromophores, and is a high-performance coloring material.

[0036] In some embodiments, the inorganic base comprises LiOH and / or NaOH, preferably LiOH.

[0037] In some embodiments, the reactive dye includes at least one of reactive blue 19, reactive orange 16, reactive blue 4, reactive red 158, reactive red 120, reactive red 195, and reactive black 5.

[0038] Specifically, the English name of Reactive Blue 19 is Reactive Blue 19, and the molecular formula is C 22 H 16 N2Na2O 11 S3; Reactive Orange 16, molecular formula: C 20 H 20 N3NaO 11 S3, alias: 6-(acetylamino)-4-hydroxy-3-[[3-[[2-(sulfonyloxy)ethyl]sulfonyl]phenyl]azo]-2-naphthalenesulfonic acid disodium salt; Reactive Blue 4 is also known as Proscien Blue MX-R, with a molecular formula of C 23 H 14 Cl2N6O8S2; Reactive Red 158, English name CIReactive red158, CAS number 64104-00-3; Reactive Red 120 is also known as Prosin Red H-E3B, ​​CAS number: 61951-82-4, molecular formula: C 44 H 30 Cl2N 14 O 20 S6; Reactive Red 195, CAS: 93050-79-4, molecular formula: C 31 H 19 ClN7Na5O 19 S6; Reactive Black 5, CAS No.: 17095-24-8, Molecular formula: C 26 H 21N5Na4O 19 S6.

[0039] In some embodiments, a reactive dye is added to a cellulose solution, and then an organic base is added to react;

[0040] The organic base includes at least one of DBU, DBN, betaine, choline chloride, trimethylamine and triethylamine.

[0041] Specifically, DBU: 1,8-diazacyclo[5,4,0]undecene-7, is a bicyclic amidine compound with strong alkalinity, CAS number: 6674-22-2, molecular formula C9H 16 N2; DBN: 1,5-diazabicyclo[4.3.0]-5-nonene, CAS No.: 3001-72-7, molecular formula C7H 12 N2; Betaine, alias: betaine, trimethylammonium betaine, etc., CAS number: 107-43-7, molecular formula: C5H 11 NO2; Choline chloride, CAS No. 67-48-1, molecular formula C5H 14 ClNO; trimethylamine is trimethylaniline, also known as 2,4,6-trimethylaniline, with a chemical formula of C9H 13 N; triethylamine is triethylamine, the chemical formula is C6H 15 N.

[0042] In some embodiments, the cotton fabric is added to a mixed solvent containing an inorganic base, urea, and water, and the mass ratio of the inorganic base, urea, and water is (5-15):(6-12):(70-90);

[0043] The mass ratio of cotton fabric to mixed solvent is (0.5-2):(5-15).

[0044] In some embodiments, in the step of adding the reactive dye to the cellulose solution, the concentration of the reactive dye is 5-200% owf.

[0045] Specifically, in the above embodiments, owf represents a concentration unit, a ratio of the weight of dye to fabric. Specifically, the concentration of the reactive dye is 5 to 200% owf, which means: for 100 g of cotton fabric, 5 to 200 g of reactive dye is used.

[0046] In some embodiments, in the step of adding a reactive dye to a cellulose solution to react, or in the step of adding a reactive dye to a cellulose solution and then adding an organic base to react, the reaction temperature is 20-70° C. and the reaction time is 30-180 min.

[0047] In some embodiments, a mixed solvent containing an inorganic base, urea and water is cooled to -5 to -12°C, and then cotton fabric is added to the cooled mixed solvent and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution.

[0048] In some embodiments, the organic base is added in an amount of 1 to 20% by mass of the cotton fabric.

[0049] In some embodiments, the method for preparing a cellulose-based polymer dye with a high-load dye color body comprises the following steps:

[0050] S1. Cooling a mixed solvent containing an inorganic base, urea and water to -5 to -12°C, then adding cotton fabric to the cooled mixed solvent, stirring to dissolve cellulose in the cotton fabric, and obtaining a cellulose solution; wherein the inorganic base is LiOH or NaOH, and the mass ratio of the inorganic base, urea and water is 11:9:80;

[0051] S2, adding the reactive dye to the cellulose solution, heating the temperature to 20-60°C at a heating rate of 1-3°C / min, and reacting for 30-150min;

[0052] S3, putting the reacted cellulose solution into water for regeneration and precipitation, separating to obtain a crude product, washing the crude product, and drying to obtain a cellulose-based polymer dye.

[0053] In some embodiments, the cellulose solution after the reaction is put into water for regeneration and precipitation, and after centrifugation, the solid and liquid are separated, and the solid product is collected to obtain a crude cellulose-based polymer dye product, which is washed to obtain a cellulose-based polymer dye without floating color; the cellulose-based polymer dye without floating color is added to water, dispersed at 8000-12000 rpm using a disperser, and then dried to obtain the final cellulose-based polymer dye.

[0054] In some embodiments, the cotton fabric includes but is not limited to cotton fabric, regenerated cellulose, cotton yarn, etc. Specifically, the cotton fabric may be waste cotton fabric.

[0055] Based on the same inventive concept, the present invention also provides a cellulose-based polymer dye, which is prepared by the above-mentioned preparation method.

[0056] The cellulose-based polymer dye of the high-load dye color body of the present application and its preparation method are further described below with specific examples. This part further illustrates the content of the present invention in conjunction with specific examples, but should not be construed as limiting the present invention. If not specifically stated, the technical means adopted in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods and equipment adopted in the present invention are conventional reagents, methods and equipment in the art.

[0057] In the following examples and comparative examples, the dye chromogen loading refers to the ratio of the amount of dye dyed onto the cellulose skeleton to the amount of cellulose during the dyeing process. The dye chromogen loading is determined by acid dissolution. 0.5 g of the prepared cellulose-based polymer dye is added to 5 mL of concentrated sulfuric acid with a mass fraction of 70% to fully dissolve, and then diluted to an appropriate concentration (determined by the ultraviolet absorbance value of the solution at the maximum wavelength of the dye between 0.2 and 0.8, and the dilution multiples of different samples are different), and its absorbance is measured and calculated by the following formula:

[0058] Dye color body loading: R1 = m1 / m0;

[0059] Wherein, R1 is the dye chromogen loading, mg / g; m0 is the mass of the original active dye; m1 is the mass of the remaining dye solution after hydrolysis with concentrated sulfuric acid; the dye concentration in the dye solution to be tested is calculated by establishing a standard curve of dye mass concentration-absorbance value at the maximum wavelength.

[0060] In the following examples, the cotton fabric used is pure cotton fabric purchased from Shandong Ruyi Woolen Textile Garment Group Co., Ltd.

[0061] Example 1

[0062] The present invention provides a method for preparing a cellulose-based polymer dye, comprising the following steps:

[0063] S1. LiOH, urea and water are mixed in a mass ratio of 11:9:80 to obtain a mixed solvent; the mixed solvent is cooled to -12°C, and then cotton fabric is added to the cooled mixed solvent, and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution; wherein the mass ratio of the cotton fabric to the mixed solvent is 1:10;

[0064] S2, adding Reactive Blue 19 to the cellulose solution in S1, heating the temperature to 60°C at a heating rate of 2°C / min, and reacting for 150 min; the concentration of Reactive Blue 19 is 100% owf;

[0065] S3, putting the cellulose solution after the reaction in S2 into water to regenerate and precipitate, centrifugally separating to obtain a crude product, washing the crude product, and drying to obtain a cellulose-based polymer dye.

[0066] Example 2

[0067] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S1, LiOH is replaced by NaOH, and the other process parameters are the same as those in Embodiment 1.

[0068] Comparative Example 1

[0069] The preparation method of the cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the preparation method of the mixed solvent in step S1 is: phosphoric acid and water are mixed in a mass ratio of 83:17 to obtain a mixed solvent; the other process parameters are the same as those in Example 1.

[0070] Comparative Example 2

[0071] The preparation method of the cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the preparation method of the mixed solvent in step S1 is: the ionic liquid [Bmim]Cl (1-butyl-3-methylimidazolium chloride, molecular formula C8H 15 N2Cl) and DMSO (dimethyl sulfoxide) were mixed in a mass ratio of 1:4 to obtain a mixed solvent; the other process parameters were the same as those in Example 1.

[0072] Comparative Example 3

[0073] The preparation method of the cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the preparation method of the mixed solvent in step S1 is: mixing the ionic liquid [Amim]Cl (1-allyl-3-methylimidazolium chloride) and DMSO (dimethyl sulfoxide) in a mass ratio of 1:4 to obtain a mixed solvent; the other process parameters are the same as those in Example 1.

[0074] Comparative Example 4

[0075] The preparation method of the cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the preparation method of the mixed solvent in step S1 is: mixing the ionic liquid [Emim]Ac (1-ethyl-3-methylimidazolium acetate) and DMSO (dimethyl sulfoxide) in a mass ratio of 1:4 to obtain a mixed solvent; the remaining process parameters are the same as those in Example 1.

[0076] Comparative Example 5

[0077] The preparation method of cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the preparation method of the mixed solvent in step S1 is: 4,4,4,4 ]OH (tetrabutylphosphonium hydroxide, molecular formula (CH3CH2CH2CH2)4P(OH)) and water are mixed in a mass ratio of 1:1 to obtain a mixed solvent; the other process parameters are the same as those in Example 1.

[0078] Comparative Example 6

[0079] The preparation method of the cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the mixed solvent in step S1 is water; the other process parameters are the same as those in Example 1.

[0080] Comparative Example 7

[0081] The preparation method of the cellulose-based polymer dye provided in this comparative example is the same as that in Example 1, except that the mixed solvent in step S1 is DMSO (dimethyl sulfoxide); the other process parameters are the same as those in Example 1.

[0082] Cellulose-based polymer dyes were prepared according to the methods in Examples 1 to 2 and Comparative Examples 1 to 7, and the effects of different solvent systems on the loading amount of dye color bodies were studied. The results are shown in Table 1 below.

[0083] Table 1 - Effect of different solvent systems on dye color body loading

[0084]

[0085] As can be seen from Table 1, the cellulose-based polymer dye prepared by the alkaline urea system has a slightly better dye chromogen loading than the ionic liquid system. This is because the alkaline environment provided by the alkaline urea system promotes the cationization of cellulose hydroxyl groups, which is beneficial to the covalent grafting reaction of the dye and cellulose hydroxyl groups. The dyeing effect of using LiOH as a solvent system is significantly better than that of NaOH. The amorphous region inside the cotton fiber can be opened by the carbonyl group on LiOH or urea. The homogeneous system significantly improves the hydroxyl activity of cellulose, and the metal lithium ions greatly reduce the electrostatic repulsion between the cotton fiber and the dye during the dyeing process. The alkalinity of the solution also meets the appropriate pH range for reactive blue 19 dyeing, which greatly increases the dye chromogen loading. Compared with the heterogeneous solid-liquid reaction, the cotton fiber is dispersed in water and DMSO. Under the same reaction conditions, the dye chromogen loading is only 2.6% and 1.9%, indicating that the use of a homogeneous system to dissolve cellulose can greatly increase the dye chromogen loading, among which LiOH / urea has the best effect.

[0086] Example 3

[0087] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 20°C (also raised to 20°C at a heating rate of 2°C / min), the reaction time is 120 min, and the concentration of Reactive Blue 19 is 5% owf; the other process parameters are the same as those in Example 1.

[0088] Example 4

[0089] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 30°C (also increased to 30°C at a heating rate of 2°C / min), the reaction time is 120min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0090] Example 5

[0091] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 40°C (also increased to 40°C at a heating rate of 2°C / min), the reaction time is 120 min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0092] Example 6

[0093] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 50°C (also increased to 50°C at a heating rate of 2°C / min), the reaction time is 120min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0094] Example 7

[0095] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 120 min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0096] Example 8

[0097] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 70°C (also increased to 70°C at a heating rate of 2°C / min), the reaction time is 120min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0098] Example 9

[0099] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 30min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0100] Example 10

[0101] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 60 min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0102] Embodiment 11

[0103] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 90min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0104] Example 12

[0105] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 120 min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0106] Example 13

[0107] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 150min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0108] Embodiment 14

[0109] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 1, except that in step S2, the reaction temperature is 60°C (also increased to 60°C at a heating rate of 2°C / min), the reaction time is 180 min, and the concentration of Reactive Blue 19 is 5% owf; the remaining process parameters are the same as those in Example 1.

[0110] Cellulose-based polymer dyes were prepared according to the methods in Examples 3 to 14 above, and the effects of different reaction temperatures and times on the loading amount of the dye color bodies were studied. The results are shown in Table 2 below.

[0111] Table 2 - Effect of different reaction temperatures and times on dye chromophore loading

[0112] Example Reaction temperature (℃) Reaction time (min) Dye color body loading (mg / g) Example 3 20 120 29.8 Example 4 30 120 34.5 Example 5 40 120 38.8 Example 6 50 120 41.5 Example 7 60 120 60.6 Example 8 70 120 53.2 Example 9 60 30 56.8 Example 10 60 60 57.4 Embodiment 11 60 90 58.1 Example 12 60 120 60.6 Example 13 60 150 64.0 Embodiment 14 60 180 64.2

[0113] As can be seen from Table 2, with the increase of temperature, the dye color body loading first increases and then decreases. This is because too high a reaction temperature will partially decompose the dye. The dye color body loading is basically the same when the reaction time is 150min and 180min. Therefore, the optimal dyeing temperature is 60℃ and the dyeing time is 150min.

[0114] Embodiment 15

[0115] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S2, the concentration of reactive blue 19 is 1% owf; the other process parameters are the same as those in Embodiment 1.

[0116] Example 16

[0117] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S2, the concentration of reactive blue 19 is 2.5% owf; the other process parameters are the same as those in Embodiment 1.

[0118] Embodiment 17

[0119] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S2, the concentration of reactive blue 19 is 5% owf; the other process parameters are the same as those in Embodiment 1.

[0120] The temperature was raised to 60°C at a heating rate of 2°C / min and the reaction was continued for 150 min; the concentration of Reactive Blue 19 was 100% owf Example 18

[0121] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S2, the concentration of reactive blue 19 is 50% owf; the other process parameters are the same as those in Embodiment 1.

[0122] Embodiment 19

[0123] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S2, the concentration of reactive blue 19 is 100% owf; the other process parameters are the same as those in Embodiment 1.

[0124] Embodiment 20

[0125] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Embodiment 1, except that in step S2, the concentration of reactive blue 19 is 200% owf; the other process parameters are the same as those in Embodiment 1.

[0126] Cellulose-based polymer dyes were prepared according to the methods in Examples 15 to 20 above, and the effects of different concentrations of Reactive Blue 19 on the loading amount of dye color bodies were studied. The results are shown in Table 3 below.

[0127] Table 3 - Effect of Reactive Blue 19 concentration on dye chromogen loading

[0128]

[0129] It can be seen from Table 3 that as the concentration of Reactive Blue 19 increases, the dye chromogen loading increases.

[0130] Embodiment 21

[0131] The present invention provides a method for preparing a cellulose-based polymer dye, comprising the following steps:

[0132] S1. LiOH, urea and water are mixed in a mass ratio of 11:9:80 to obtain a mixed solvent; the mixed solvent is cooled to -12°C, and then cotton fabric is added to the cooled mixed solvent, and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution; wherein the mass ratio of the cotton fabric to the mixed solvent is 1:10;

[0133] S2, adding Reactive Blue 19 to the cellulose solution in S1, and adding DBU at a DBU concentration of 5%, heating the temperature to 60°C at a heating rate of 2°C / min, and reacting for 150min; the concentration of Reactive Blue 19 is 100% owf;

[0134] S3, putting the cellulose solution after the reaction in S2 into water to regenerate and precipitate, centrifugally separating to obtain a crude product, washing the crude product, and drying to obtain a cellulose-based polymer dye.

[0135] Embodiment 22

[0136] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that DBU is replaced by DBN in step S2 (the DBN concentration is also 5%), and the other process parameters are the same as those in Example 21.

[0137] Embodiment 23

[0138] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that DBU is replaced with betaine in step S2 (the concentration of betaine is also 5%), and the other process parameters are the same as those in Example 21.

[0139] Embodiment 24

[0140] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that DBU is replaced with choline chloride (the concentration of choline chloride is also 5%) in step S2, and the other process parameters are the same as those in Example 21.

[0141] Embodiment 25

[0142] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that DBU is replaced by trimethylamine in step S2 (the concentration of trimethylamine is also 5%), and the other process parameters are the same as those in Example 21.

[0143] Embodiment 26

[0144] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that DBU is replaced with triethylamine (the concentration of triethylamine is also 5%) in step S2, and the other process parameters are the same as those in Example 21.

[0145] Embodiment 27

[0146] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that the DBU concentration in step S2 is 1%, and the other process parameters are the same as those in Example 21.

[0147] Embodiment 28

[0148] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that the DBU concentration in step S2 is 2.5%, and the other process parameters are the same as those in Example 21.

[0149] Embodiment 29

[0150] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that the DBU concentration in step S2 is 10%, and the other process parameters are the same as those in Example 21.

[0151] Embodiment 30

[0152] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 21, except that the DBU concentration in step S2 is 20%, and the other process parameters are the same as those in Example 21.

[0153] Cellulose-based polymer dyes were prepared according to the methods in Examples 21 to 30 above, and the effects of different organic bases on the loading amount of the dye color body were studied. The results are shown in Table 4 below.

[0154] Table 4 - Effect of different organic bases on the loading amount of dye chromogen

[0155]

[0156] The control group in Table 4 is Example 1, i.e. no organic base is added.

[0157] From Table 4

[0158] It can be seen that by dissolving cellulose in the LiOH / urea / water system of the present invention, a high dye chromogen loading amount can be achieved by adding a low concentration of DBU in the homogeneous reaction. When the DBU concentration is 10%, the dye chromogen loading amount is the highest, which is 262.5 mg / g. The homogeneous system of the present invention greatly improves the dye chromogen loading amount, and while ensuring the dye loading amount, solves the problem of adding a large amount of electrolyte to the dye solution for dyeing promotion and alkali fixation in the prior art.

[0159] Embodiment 31

[0160] The present invention provides a method for preparing a cellulose-based polymer dye, comprising the following steps:

[0161] S1. LiOH, urea and water are mixed in a mass ratio of 11:9:80 to obtain a mixed solvent; the mixed solvent is cooled to -12°C, and then cotton fabric is added to the cooled mixed solvent, and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution; wherein the mass ratio of the cotton fabric to the mixed solvent is 1:10;

[0162] S2, adding active orange 16 to the cellulose solution in S1, and adding DBU at the same time, the DBU concentration is 10%, and the temperature is raised to 60°C at a heating rate of 2°C / min, and the reaction is carried out for 150min; the concentration of active orange 16 is 100% owf;

[0163] S3, putting the cellulose solution after the reaction in S2 into water to regenerate and precipitate, centrifugally separating to obtain a crude product, washing the crude product, and drying to obtain a cellulose-based polymer dye.

[0164] Embodiment 32

[0165] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 31, except that reactive orange 16 is replaced by reactive blue 4 in step S2, and the other process parameters are the same as those in Example 31.

[0166] Embodiment 33

[0167] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 31, except that in step S2, reactive orange 16 is replaced by reactive red 158, and the other process parameters are the same as those in Example 31.

[0168] Embodiment 34

[0169] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 31, except that in step S2, reactive orange 16 is replaced by reactive red 120, and the other process parameters are the same as those in Example 31.

[0170] Embodiment 35

[0171] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 31, except that in step S2, reactive orange 16 is replaced by reactive red 195, and the other process parameters are the same as those in Example 31.

[0172] Embodiment 36

[0173] The preparation method of the cellulose-based polymer dye provided in this embodiment is the same as that in Example 31, except that in step S2, reactive orange 16 is replaced by reactive black 5, and the other process parameters are the same as those in Example 31.

[0174] Cellulose-based polymer dyes were prepared according to the methods in Examples 31 to 36 above, and the effects of different reactive dyes on the loading amount of dye color bodies were studied. The results are shown in Table 5 below.

[0175] Table 5 - Effect of different reactive dyes on dye color body loading

[0176] Example Reactive dye types DBU concentration Dye color body loading (mg / g) Embodiment 31 Reactive Orange 16 10％ 198.5 Embodiment 32 Reactive Blue 4 10％ 226.9 Embodiment 33 Reactive Red 158 10％ 268.3 Embodiment 34 Reactive Red 120 10％ 236.9 Embodiment 35 Reactive Red 195 10％ 243.3 Embodiment 36 Reactive Black 5 10％ 251.3

[0177] It can be seen from Table 5 that when different reactive dyes are used, they all have a higher dye color body loading amount. It can be seen that the LiOH / urea / water homogeneous system of the present invention greatly increases the dye color body loading amount.

[0178] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a cellulose-based polymer dye, characterized in that: The following steps are involved: Adding cotton fabric into a mixed solvent containing an inorganic base, urea and water, stirring, and obtaining a cellulose solution; adding a reactive dye into a cellulose solution to react; The cellulose solution after the reaction is added into water to regenerate and precipitate, and separated to obtain a crude product, and the crude product is washed and dried to obtain a cellulose-based polymer dye.

2. The method for preparing a cellulose-based polymer dye according to claim 1, wherein: The inorganic base includes LiOH and / or NaOH; And / or, the reactive dye includes at least one of reactive blue 19, reactive orange 16, reactive blue 4, reactive red 158, reactive red 120, reactive red 195, and reactive black 5.

3. The method for preparing a cellulose-based polymer dye according to claim 1, wherein: Adding a reactive dye to a cellulose solution, and then adding an organic base to react; Wherein, the organic base includes at least one of DBU, DBN, betaine, choline chloride, trimethylamine and triethylamine.

4. The method for preparing a cellulose-based polymer dye according to claim 1, wherein: The step of adding cotton fabric to a mixed solvent containing an inorganic base, urea and water, wherein the mass ratio of the inorganic base, urea and water is (5-15):(6-12):(70-90); The mass ratio of cotton fabric to mixed solvent is (0.5-2):(5-15).

5. The method for preparing a cellulose-based polymer dye according to claim 1, wherein: In the step of adding the reactive dye to the cellulose solution, the concentration of the reactive dye is 5 to 200% owf.

6. The method for preparing a cellulose-based polymer dye according to claim 1 or 3, characterized in that: In the step of adding the active dye to the cellulose solution to carry out the reaction, or in the step of adding the active dye to the cellulose solution and then adding the organic base to carry out the reaction, the reaction temperature is 20-70° C. and the reaction time is 30-180 min.

7. The method for preparing a cellulose-based polymer dye according to any one of claims 1 to 5, characterized in that: The mixed solvent containing inorganic alkali, urea and water is cooled to -5 to -12°C, and then cotton fabric is added to the cooled mixed solvent, and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution.

8. The method for preparing a cellulose-based polymer dye according to claim 3, wherein: The amount of organic alkali added is 1-20% of the mass of the cotton fabric.

9. The method for preparing a cellulose-based polymer dye according to claim 7, wherein: The following steps are involved: The mixed solvent containing inorganic base, urea and water is cooled to -5 to -12°C, and then cotton fabric is added to the cooled mixed solvent, and stirred to dissolve cellulose in the cotton fabric to obtain a cellulose solution; wherein the inorganic base is LiOH or NaOH, and the mass ratio of the inorganic base, urea and water is 11:9:80; Add the reactive dye to the cellulose solution, raise the temperature to 20-60°C at a heating rate of 1-3°C / min, and react for 30-150 minutes; The cellulose solution after the reaction is put into water for regeneration and precipitation, and separated to obtain a crude product. The crude product is washed and dried to obtain a cellulose-based polymer dye.

10. A cellulose-based polymer dye, characterized in that: The preparation method is as described in any one of claims 1 to 9.

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