阅读说明：本技术 一种粘胶纤维原液纺丝用阻燃浆料及其制备方法 (Flame-retardant slurry for viscose stock solution spinning and preparation method thereof ) 是由 杜长森 梁栋 胡冲 梅成国 于 2019-10-16 设计创作，主要内容包括：本发明公开了一种粘胶纤维原液纺丝用阻燃浆料及其制备方法。该阻燃浆料包括阻燃剂、表面活性剂、润湿剂、抗氧化剂等组分。该阻燃浆料利用各个原料经混合、分散、研磨、过滤等步骤制备而得。该阻燃浆料储存稳定性好,可纺性高,阻燃剂在粘胶纤维中的牢度高,分散性好,使粘胶纤维的极限氧指数较高。(The invention discloses flame-retardant slurry for viscose stock solution spinning and a preparation method thereof. The flame-retardant slurry comprises components such as a flame retardant, a surfactant, a wetting agent, an antioxidant and the like. The flame-retardant slurry is prepared by mixing, dispersing, grinding, filtering and the like of all raw materials. The flame-retardant slurry has good storage stability, high spinnability, high fastness of the flame retardant in the viscose fiber, good dispersibility and higher limited oxygen index of the viscose fiber.)

1. The flame-retardant slurry is characterized in that water is used as a dispersion medium, and the flame-retardant slurry comprises the following components:

a flame retardant accounting for 20-50% of the total mass of the flame retardant slurry,

2-10% by mass of a surfactant A relative to the mass of the flame retardant,

2-4% by mass of a surfactant B based on the mass of the flame retardant,

2-4% by mass of a surfactant C relative to the mass of the flame retardant,

1 to 5% by mass of a wetting agent based on the mass of the flame retardant,

1-4% by mass of an antioxidant with respect to the mass of the flame retardant,

wherein the surfactant A is a compound with a structure of a general formula (I):

in the general formula (I), R₁Is CH₃、CH₂COOH、CH₂COONa、CH₂CH₂OH、CH₂CH(CH₃) One of OH; n is an integer of 10-16, and comprises 10 and 16;

the surfactant B is a compound having the structural formula (II):

the surfactant C is a compound with a structure of a general formula (III):

in the general formula (III), R₂Is an alkyl or aryl group having 7 to 30 carbon atoms; y is Na, K, NH₄One kind of (1).

2. The slurry of claim 1, wherein the flame retardant is N, N' -bis (5, 5-dimethyl-2-phospha-2-thioxo-1, 3-dioxan-2-yl) ethylenediamine.

3. The flame-retardant slurry according to claim 1, wherein the wetting agent is a compound having a structure of formula (iv):

wherein R is₃Is an alkyl or aryl group having 7 to 30 carbon atoms; a is an integer of 1-40 and comprises 1 and 40; b is an integer of 1-40, and comprises 1 and 40; c is an integer of 1 to 40, and includes 1 and 40.

4. The flame-retardant slurry as claimed in claim 1, wherein the antioxidant is a phenolic antioxidant and a phosphite antioxidant in a mass ratio of 1: 0.5 to 1.

5. The flame retardant slurry according to claim 1, further comprising an antifoaming agent in an amount of 0.05 to 0.5% by mass based on the total mass of the flame retardant slurry, wherein the antifoaming agent is preferably at least one of a polysiloxane ether copolymer antifoaming agent and a polyether compound antifoaming agent.

6. The flame-retardant slurry according to claim 1, further comprising a mildew-proof bactericide which accounts for 0.05-0.5% of the total mass of the flame-retardant slurry, wherein the mildew-proof bactericide is preferably at least one of imidazole, thiazole, isothiazolone derivatives, quaternary ammonium salts or biguanide mildew-proof bactericides.

7. The method for preparing a flame retardant slurry according to any one of claims 1 to 6, characterized by comprising the steps of:

(a) preparation of mixed solution: dispersing a surfactant A, a surfactant B, a surfactant C, a wetting agent and an antioxidant into water, and adjusting the pH value to 8.0-10.0 by using a pH value regulator to obtain a mixed solution;

(b) preparing flame-retardant slurry: adding a flame retardant into the mixed solution prepared in the step (a), and dispersing, grinding and filtering to obtain the flame-retardant slurry.

8. The method of claim 7, wherein the pH regulator in step (a) is one or a combination of more than two of sodium hydroxide, potassium hydroxide, ammonia water, sodium bicarbonate and triethanolamine.

9. The method for preparing a flame retardant slurry according to claim 7, wherein a mildew preventive bactericide is further added in the step (a), and a defoaming agent is added in the grinding process in the step (b).

10. Use of a flame retardant size according to any of claims 1 to 6 in viscose dope spinning.

Technical Field

The invention relates to flame-retardant slurry and a preparation method thereof, in particular to flame-retardant slurry for viscose stock solution spinning and a preparation method thereof, belonging to the technical field of fine chemical engineering.

Background

The viscose fiber is a regenerated cellulose fiber obtained by a series of chemical processing processes of caustic soda dipping, carbon disulfide combination, dissolving in dilute alkali and the like on natural cellulose pulp such as wood fiber or cotton linter and the like which cannot be directly spun to prepare viscose spinning solution, spraying the viscose spinning solution into a spinning acid bath through a spinneret orifice, and carrying out spinning processes such as solidification, regeneration and the like. The viscose fiber has the characteristics of good hygroscopicity and air permeability, soft texture, high wearing comfort, good air permeability and antistatic property, ultraviolet resistance and the like, and is the regenerated cellulose fiber which is most widely applied at present.

In order to increase the functionality of the viscose fiber, materials with special functions are often added to make the viscose fiber have special functionality, so as to improve the application performance and the added value of the viscose fiber. Because viscose fiber is flammable and has a high combustion speed, in order to prevent the harm caused by the combustion of the viscose fiber, a flame retardant is often added into a stock solution before spinning so as to ensure that the viscose fiber obtains the flame retardant property.

The flame retardant used for the flame-retardant viscose fiber can be a silicon-containing flame retardant, a phosphorus-nitrogen series compound flame retardant and the like. And for the granular flame retardant, preparing the granular flame retardant into slurry which is stably dispersed in an aqueous system, directly adding the slurry into spinning solution, and then carrying out processes such as mixing with the spinning solution, spinning and the like to obtain the flame-retardant fiber. However, the directly purchased flame retardant has the defects of large particle size, wide particle size distribution, poor compatibility of the flame retardant and a spinning solution and the like, the flame retardant can be settled after being placed for a period of time, and when the flame retardant is used, particularly in the spinning process of viscose fiber stock solutions, the spinnerets are blocked due to the reasons of large particle size, coarse returning or poor compatibility with the spinning solution and the like of the flame retardant, so that the spinnability is poor, and the prepared viscose fiber has the problems of rough surface, uneven distribution of the flame retardant, poor fastness to washing and the like.

Patent US776180 discloses a method for preparing a fire-retardant delustering zinc-free cellulose product, which comprises adding silicate into viscose stock solution, mixing, filtering, spinning, coagulating in a coagulating bath containing sulfuric acid, sodium sulfate and aluminum sulfate instead of conventional zinc sulfate. Patent CN201110252275.0 discloses a flame retardant dispersion and a preparation method thereof, wherein the dispersion contains the following components: the fire retardant is N, N' -bis (5, 5-dimethyl-2-phospha-2-thio-1, 3-dioxane-2-yl) ethylenediamine (DDPSN for short), the wetting agent is alcohols such as ethanol propanol and the like, the high molecular dispersing agent is a sodium polycarboxylate dispersing agent or an ammonium polyacrylate dispersing agent, and the deflocculating agent dispersing agent is an alkylhydroxyaminoamide deflocculating dispersing agent. Patent CN201210024526.4 discloses a flame-retardant viscose fiber and a preparation method thereof, all the flame-retardant emulsions contain the following components: n, N' -bis (5, 5-dimethyl-2-phospha-2-thioxo-1, 3-dioxan-2-yl) ethylenediamine, tris (2-chloropropyl) phosphate, cocamidopropyl dimethylbetaine, potassium dodecyl phosphate, tween-60 and water.

DDPSN is commonly used as a flame retardant in viscose fibers, but DDPSN is insoluble in water and has poor compatibility with the viscose fibers, and the existing dispersion technology cannot meet the requirements of stable DDPSN dispersoid and good compatibility with the viscose fibers, so that a spinning nozzle is easily blocked in the spinning process of the viscose fibers, the spinnability of viscose stock solution added with flame retardant slurry is poor, and the prepared viscose fibers have the problems of rough surface, uneven distribution of the flame retardant, poor fastness to washing and the like.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide the flame-retardant slurry and the preparation method thereof, the compounding of the surfactant B and the surfactant C in the flame-retardant slurry can play a role in synergy, and the existence of a wetting agent and an antioxidant is favorable for stable dispersion of a flame retardant; the surfactant A has a similar structure to viscose, and can improve the compatibility of the flame retardant and viscose and enhance the fastness of the flame retardant in viscose when being applied to viscose stock solution spinning; the flame-retardant slurry has good storage stability and high spinnability, and the flame retardant in the flame-retardant slurry has good dispersibility in the viscose fiber, so that the limiting oxygen index of the viscose fiber is higher.

In order to achieve the technical purpose and achieve the technical effect, the invention is realized by the following technical scheme:

the invention discloses a flame-retardant slurry, which takes water as a dispersion medium and comprises the following components:

a flame retardant accounting for 20-50% of the total mass of the flame retardant slurry,

2-10% by mass of a surfactant A relative to the mass of the flame retardant,

2-4% by mass of a surfactant B based on the mass of the flame retardant,

2-4% by mass of a surfactant C relative to the mass of the flame retardant,

1 to 5% by mass of a wetting agent based on the mass of the flame retardant,

1-4% by mass of an antioxidant with respect to the mass of the flame retardant,

wherein the surfactant A is a compound with a structure of a general formula (I):

in the general formula (I), R₁Is CH₃、CH₂COOH、CH₂COONa、CH₂CH₂OH、CH₂CH(CH₃) One of OH; n is an integer of 10-16, and comprises 10 and 16; the preparation method of the surfactant A comprises the following steps: with R₁Is CH₃For example, the surfactant A is prepared by using carboxymethyl cellulose as a raw material and C₁₂-C₁₈The alkyl acyl chloride is used as an etherifying agent, NaOH is used as a catalyst, and the alkyl acyl chloride is prepared by reaction in a medium of dimethyl formamide and water. When the flame-retardant slurry is applied to the preparation process of viscose, the flame retardant is wrapped by the surfactant A when the viscose is formed in the coagulating bath, and the flame retardant is easily wrapped by the viscose due to the similarity of the structure of the surfactant A and the structure of the viscose, so that the fastness of the flame retardant in the viscose is improved.

Wherein the surfactant B is a compound having the structural formula (II):

the preparation method of the surfactant B comprises the following steps: reacting rosin and maleic anhydride under the conditions of a catalyst and a heating condition, and then slowly adding diethanolamine to continue reacting to obtain a surfactant B. The surfactant B has an aromatic ring structure, has a large hydrophobic group, contains a plurality of hydroxyl groups, amide groups and other hydrophilic groups, and has good water solubility.

Wherein the surfactant C is a compound having a structure of general formula (III):

in the general formula (III),R₂is an alkyl or aryl group having 7 to 30 carbon atoms; y is Na, K, NH₄One kind of (1). The preparation method of the surfactant C comprises the following steps: r₂COOCH₃And the ethanolamine reacts with sodium methoxide serving as a catalyst under the heating condition, then the ethanolamine continuously reacts with maleic anhydride, and finally the surfactant C is obtained by reacting with sulfite. The surfactant B and the surfactant C both contain flame-retardant elements, so that the flame retardant property can be improved, and meanwhile, the two surfactants can generate a synergistic effect by compounding, so that the flame retardant can be stably dispersed, and the compatibility with a viscose stock solution is good.

In the technical scheme, N' -bis (5, 5-dimethyl-2-phospha-2-thio-1, 3-dioxane-2-yl) ethylenediamine is preferably selected as the flame retardant, the English abbreviation name of the flame retardant is DDPSN, the flame retardant is insoluble in water and has water resistance, the melting point is 291 ℃, and the flame retardant simultaneously contains three flame retardant elements of nitrogen, phosphorus and sulfur, the three flame retardant elements have synergistic effects, can react with hydroxyl in cellulose, and has a good flame retardant effect.

Further, the wetting agent is a compound with a structure of a general formula (IV):

in the general formula (IV), R₃Is an alkyl or aryl group having 7 to 30 carbon atoms; a is an integer of 1-40 and comprises 1 and 40; b is an integer of 1-40, and comprises 1 and 40; c is an integer of 1 to 40, and includes 1 and 40. The preparation method of the wetting agent comprises the following steps: r₃OH sequentially reacts with ethylene oxide, propylene oxide and ethylene oxide, and finally reacts with phosphorus trichloride to obtain the wetting agent.

In order to avoid the oxidation of the flame retardant during long-term storage or use, an antioxidant is added into the flame retardant slurry; wherein the antioxidant is a phenolic antioxidant and a phosphite antioxidant in a mass ratio of 1: 0.5 to 1. Wherein the phenolic antioxidant is preferably pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate (trade name is antioxidant 1010); the phosphite antioxidant is preferably tris (2, 4-di-tert-butylphenyl) phosphite (trade name antioxidant 168).

In order to prevent the flame retardant slurry from generating bubbles in the preparation process to influence the spinning effect, a defoaming agent accounting for 0.05-0.5% of the total mass of the flame retardant slurry can be added into the flame retardant slurry; the defoaming agent is preferably at least one of a polysiloxane ether copolymer defoaming agent and a polyether compound defoaming agent.

In order to prevent the flame-retardant slurry from mildewing due to certain special strains in the long-time storage process, a mildew-proof bactericide which accounts for 0.05-0.5% of the total mass of the flame-retardant slurry can be added into the flame-retardant slurry; the mildew-proof bactericide is preferably at least one of imidazole, thiazole, isothiazolone derivatives, quaternary ammonium salts or biguanide mildew-proof bactericide.

The invention also discloses a preparation method of the flame-retardant slurry, which comprises the following steps:

(a) preparation of surfactant mixed solution: dispersing a surfactant A, a surfactant B, a surfactant C, a wetting agent, an antioxidant and a mildew-proof bactericide into water, and adjusting the pH value to 8.0-10.0 by using a pH value regulator to obtain a mixed solution;

(b) preparing flame-retardant slurry: adding a flame retardant into the mixed solution prepared in the step (a), and dispersing, grinding and filtering to obtain the flame-retardant slurry. The dispersing, grinding and filtering processes are all common processes for preparing slurry, and are not described in detail herein.

Wherein, the pH value regulator in the step (a) is preferably one or the combination of more than two of sodium hydroxide, potassium hydroxide, ammonia water, sodium bicarbonate and triethanolamine.

In the step (b), a defoaming agent is added in the grinding process to prevent the flame-retardant slurry from generating bubbles; the grinding process generally selects a sand mill for grinding.

The invention also discloses application of the flame-retardant slurry in viscose stock solution spinning.

The invention has the beneficial effects that: the flame-retardant slurry contains a flame retardant, a surfactant A, a surfactant B, a surfactant C, a wetting agent, an antioxidant, a mildew-proof bactericide and a defoaming agent, wherein the surfactant B and the surfactant C both contain flame-retardant elements, so that the flame retardance can be improved, and meanwhile, the compounding of the two surfactants can play a role in synergy, so that the flame retardant can be stably dispersed, and the compatibility of the flame retardant and a viscose fiber stock solution is good; the existence of the wetting agent and the antioxidant in the flame retardant slurry is beneficial to the stable dispersion of the flame retardant, and the antioxidant can also avoid the oxidation of the flame retardant; the surfactant A in the flame-retardant slurry is similar to the structure of viscose, so that when the viscose is formed in a coagulating bath, the flame retardant is easily wrapped by the viscose, the fastness of the flame retardant in the viscose is improved, and the storage stability and the spinnability are improved. The flame-retardant slurry prepared by the invention has high storage stability and spinnability, and the flame retardant has good dispersibility in the viscose fiber, so that the prepared viscose fiber has higher limit oxygen index.

Detailed Description

The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to more readily understand the advantages and features of the present invention, and to clearly and unequivocally define the scope of the present invention.

The flame retardants used in the following specific examples and comparative examples are each N, N' -bis (5, 5-dimethyl-2-phospha-2-thioxo-1, 3-dioxan-2-yl) ethylenediamine.

The chemical structures of the surfactant a, the surfactant C and the wetting agent used in the following specific examples and comparative examples are as follows:

the surfactant A is a compound with a structure of a general formula (I):

in the general formula (I), R₁Is CH₃、CH₂COOH、CH₂COONa、CH₂CH₂OH、CH₂CH(CH₃) One of OH; n is an integer of 10-16, and comprises 10 and 16;

in the structural formula of the surfactant A1, R₁Is CH₂COONa, n is 14, and the relative molecular mass of the surfactant A1 is about 6100;

in the structural formula of the surfactant A2, R₁Is CH₃And n is 16, the relative molecular mass of the surfactant A2 is about 5600;

in the structural formula of the surfactant A3, R₁Is CH₂CH₂OH, n is 10, and the relative molecular mass of the surfactant A3 is about 4900;

surfactant C is a compound having the structure of formula (iii):

in the general formula (III), R₂Is an alkyl or aryl group having 7 to 30 carbon atoms; y is Na, K, NH₄One of (1);

in the structural formula of the surfactant C1, R₂Is C₁₅H₃₁Y is NH₄；

In the structural formula of the surfactant C2, R₂Is C₇H₁₅Y is K;

in the structural formula of the surfactant C3, R₂Is Ph-C₂₄H₄₈Y is Na;

the wetting agent is a compound with a structure of a general formula (IV):

wherein R is₃Is an alkyl or aryl group having 7 to 30 carbon atoms; a is an integer of 1-40 and comprises 1 and 40; b is an integer of 1-40, and comprises 1 and 40; c is an integer of 1-40, and comprises 1 and 40;

wetting agent A1 formula, R₃Is C₁₄H₂₉A is 20, b is 40, c is 22;

wetting agent A2 formula, R₃Is Ph-C₂₄H₄₈A is 1, b is 20, c is 40;

wetting agent A3 formula, R₃Is C₇H₁₅A is 40, b is 1, and c is 1.

The surfactants B used in the following specific examples and comparative examples are compounds of the formula (II):