阅读说明：本技术 一种多羟基磺酸胺盐的制备方法及其应用 (Preparation method and application of polyhydroxy sulfonic acid amine salt ) 是由 吴后胜 汤嘉陵 苏始朝 张崇照 于 2021-06-18 设计创作，主要内容包括：本发明涉及有机化学合成技术领域,尤其涉及一种多羟基磺酸胺盐的制备方法及其制备方法。具体制备步骤包括：(1)制备多羟基磺酸；(2)将多羟基磺酸与叔胺化合物反应,得到多羟基磺酸胺盐；所述多羟基磺酸为羟基个数为1-4的链烷磺酸。采用本发明合成的多羟基磺酸胺盐有利于水性聚氨酯合成反应的稳定进行,本发明产物为液态状态,在合成聚氨酯的过程中可充当扩链剂和溶剂双重身份,不需要额外添加溶剂；反应过程平稳可控,形成的聚氨酯分子结构易于设计,提升了聚氨酯合成的可行性和精确可控性；同时能够使聚氨酯的固含量达到60％左右,实现了高固含量水性聚氨酯的技术合成；本发明成本低廉,工艺简便,绿色环保,应用前景广阔。(The invention relates to the technical field of organic chemical synthesis, in particular to a preparation method of polyhydroxy sulfonic acid amine salt and a preparation method thereof. The preparation method comprises the following specific steps: (1) preparing polyhydroxy sulfonic acid; (2) reacting polyhydroxysulfonic acid with a tertiary amine compound to obtain polyhydroxysulfonic acid amine salt; the polyhydroxy sulfonic acid is alkane sulfonic acid with 1-4 hydroxyl groups. The polyhydroxy sulfonic acid amine salt synthesized by the method is beneficial to the stable synthesis reaction of waterborne polyurethane, the product is in a liquid state, and can serve as the dual identities of a chain extender and a solvent in the process of synthesizing polyurethane without adding extra solvent; the reaction process is stable and controllable, the molecular structure of the formed polyurethane is easy to design, and the feasibility and the accurate controllability of polyurethane synthesis are improved; meanwhile, the solid content of the polyurethane can reach about 60 percent, and the technical synthesis of the high-solid-content aqueous polyurethane is realized; the invention has the advantages of low cost, simple and convenient process, environmental protection and wide application prospect.)

1. The preparation method of the polyhydroxy sulfonic acid amine salt is characterized by comprising the following specific preparation steps:

(1) preparing polyhydroxy sulfonic acid;

(2) reacting polyhydroxysulfonic acid with a tertiary amine compound to obtain polyhydroxysulfonic acid amine salt;

the polyhydroxy sulfonic acid is alkane sulfonic acid with 1-4 hydroxyl groups.

2. The method according to claim 1, wherein the polyhydroxysulfonic acid is an alkanesulfonic acid having a hydroxyl group number of 2; wherein the number of carbon atoms among carbon atoms connected with 2 hydroxyl groups is n, and n is more than or equal to 0 and less than or equal to 6.

3. The method for producing an amine salt of polyhydroxysulfonic acid according to claim 1 or 2, wherein the tertiary amine compound has a surface tension of 10 to 50dyne/cm and a boiling point of 35 to 126 ℃.

4. The method for preparing an amine salt of a polyhydroxysulfonic acid according to claim 2, wherein the alkanesulfonic acid having a hydroxyl number of 2 is prepared by:

the first step is as follows: preparing alkanesulfonate with the hydroxyl number of 2;

the second step is that: acidifying the alkane sulfonate with the hydroxyl number of 2 to obtain a crude material;

the third step: and purifying the crude material to obtain the alkane sulfonic acid finished product with the hydroxyl number of 2.

5. The method of claim 4, wherein the first step is carried out by mixing C2-C6 alkylene glycol with bisulfite in water medium to obtain alkanesulfonic acid salt with hydroxyl number of 2.

6. The method of claim 4, wherein the first step is carried out by reacting halogenated hydroxysulfonic acid with strong base weak acid salt in an aqueous medium to obtain alkanesulfonic acid salt having 2 hydroxyl groups.

7. The method according to claim 5, wherein the pH of the reactants is controlled to 6.5 to 7.5 by using a pH adjusting agent in the first step.

8. The process according to any one of claims 4 to 7, wherein in the second step, an alkanesulfonic acid having a hydroxyl number of 2 is acidified with a strong acid; the strong acid comprises HClO₄，HI，H₂SO₄，HBr，HCl，HNO₃，HIO₃At leastOne kind of the medicine.

9. The method according to any one of claims 4 to 8, wherein the third purification step is carried out by feeding the crude material into a material separation device, and removing low-boiling impurities to obtain a finished alkanesulfonic acid product having a hydroxyl number of 2.

10. Use of the amine salt of a polyhydroxy sulfonic acid according to any of claims 1 to 9 for the preparation of aqueous polyurethanes.

Technical Field

The invention relates to the technical field of organic chemical synthesis, in particular to a preparation method and application of polyhydroxy sulfonic acid amine salt.

Background

The waterborne polyurethane is a macromolecular emulsion formed by dispersing polyurethane by taking water as a medium, and has the advantages of greenness, no pollution, good compatibility, safety, reliability, convenience in operation and processing and the like, so that the waterborne polyurethane is widely applied to the fields of coatings, adhesives and the like. The aqueous polyurethane has various varieties, the raw materials and the formula are diversified, and the polyurethane can be divided into anionic aqueous polyurethane, cationic aqueous polyurethane and nonionic aqueous polyurethane according to the property of hydrophilic groups on the side chain or the main chain of a polyurethane molecule, wherein the anionic aqueous polyurethane is superior to the cationic aqueous polyurethane and the nonionic aqueous polyurethane in the aspects of mechanical property, hydrophilicity, stability and the like, and has the highest share in the market.

The chain extender commonly used for the anionic polyurethane comprises a carboxylic acid type and a sulfonic acid type, the conventional dimethylolpropionic acid (DMPA) and dimethylolbutyric acid (DMBA) react with isocyanate by utilizing carboxyl in a molecular structure, and the reaction process is stable, but the chain extender has low ionization degree, poor temperature resistance and mechanical property, is difficult to synthesize the waterborne polyurethane emulsion with stable performance and solid content of more than 38 percent; meanwhile, the polyurethane emulsion has stronger crystallinity, can be dissolved only by a high-boiling point solvent (such as N-methyl pyrrolidone, dimethyl formamide and the like), has high VOC content of the polyurethane emulsion, and is contrary to the development trend of green environment-friendly materials. The sulfonic acid chain extender, especially the sulfamate, can synthesize the polyurethane emulsion with the solid content of more than 50 percent due to high reaction activity. However, sodium sulfonate cannot be dissolved in a common organic solvent during storage, and can only be supplied in the form of an aqueous solution; in the emulsification stage of polyurethane synthesis, isocyanate, amino and water can react rapidly, a large amount of organic solvent is required to be added to dilute viscosity, the process has high requirements on equipment and process, and the reaction process is difficult to control. Based on the above, it is an urgent problem in the art to explore a chain extender which can not only enable the polyurethane reaction to occur smoothly, but also can obtain polyurethane with high solid content.

Disclosure of Invention

The invention provides a preparation method of polyhydroxy sulfonic acid amine salt, which solves the defect that the chain extender for waterborne polyurethane in the prior art is difficult to give consideration to solid content and reaction controllability, and realizes the preparation of polyhydroxy sulfonic acid amine salt chain extender with high solid content and stable and controllable reaction process.

The invention provides a preparation method of polyhydroxy sulfonic acid amine salt, which comprises the following steps:

(1) preparing polyhydroxy sulfonic acid;

(2) reacting polyhydroxy sulfonic acid with tertiary amine compound to obtain polyhydroxy sulfonic acid amine salt.

In a preferred embodiment, the polyhydroxysulphonic acid is an alkanesulphonic acid having a hydroxyl number of from 1 to 4.

In a preferred embodiment, the polyhydroxysulfonic acid is an alkanesulfonic acid having a hydroxyl number of 2; wherein the number of carbon atoms among carbon atoms connected with 2 hydroxyl groups is n, and n is more than or equal to 0 and less than or equal to 6.

In a preferred embodiment, the tertiary amine compound has a surface tension of 10 to 50dyne/cm and a boiling point of 35 to 126 ℃.

In a preferred embodiment, the alkanesulfonic acid having a hydroxyl number of 2 is prepared by:

the first step is as follows: preparing alkanesulfonate with the hydroxyl number of 2;

the second step is that: acidifying the alkane sulfonate with the hydroxyl number of 2 to obtain a crude material;

the third step: and purifying the crude material to obtain the alkane sulfonic acid finished product with the hydroxyl number of 2.

In a preferred embodiment, the first step is to mix and react C2-C6 alkylene glycol with bisulfite in an aqueous medium to obtain alkanesulfonate with 2 hydroxyl groups.

In a preferred embodiment, the first step is specifically that the halogenated hydroxysulfonic acid is mixed and reacted with strong base weak acid salt in an aqueous medium to obtain alkane sulfonate with 2 hydroxyl groups.

Further preferably, the strong base and weak acid salt comprises at least one of carbonate, acetate and bicarbonate.

In a preferred embodiment, in the first step, the pH of the reactants is controlled to be always maintained at 6.5 to 7.5 using a pH adjuster.

In a preferred embodiment, in the second step, an alkanesulfonate having a hydroxyl number of 2 is acidified with a strong acid; the strong acid comprises HClO₄，HI，H₂SO₄，HBr，HCl，HNO₃，HIO₃At least one of (1).

Further preferably, the strong acid is in a gaseous state; still more preferably, the strong acid is hydrogen chloride gas.

In a preferred embodiment, the third purification step is to put the crude material into a material separation device, remove low boiling point impurities, and obtain a finished product of alkanesulfonic acid with a hydroxyl number of 2.

The second aspect of the invention provides application of a preparation method of polyhydroxy sulfonic acid amine salt, and the polyhydroxy sulfonic acid amine salt is applied to preparation of waterborne polyurethane.

Has the advantages that:

the polyhydroxy sulfonic acid amine salt prepared by the invention has the following advantages:

(1) the polyhydroxy sulfonic acid amine salt synthesized by the method is beneficial to the stable synthesis reaction of waterborne polyurethane, the product is in a liquid state, and can serve as the dual identities of a chain extender and a solvent in the process of synthesizing polyurethane without adding extra solvent; the reaction process is stable and controllable, solvent metering reaction is not needed in the whole process, the molecular structure of the formed polyurethane is easy to design, and the feasibility and the accurate controllability of polyurethane synthesis are improved;

(3) the solid content of polyurethane formed by the cross-linking reaction of the synthesized polyhydroxy sulfonic acid amine salt, the polyol polymer and the isocyanate can reach about 60 percent, and the technical synthesis of the high-solid-content waterborne polyurethane is realized;

(4) the polyhydroxy sulfonic acid amine salt synthesized by the invention overcomes the defect that the chain extender for waterborne polyurethane in the prior art is difficult to take account of solid content and reaction controllability, has low cost and simple and convenient process, is green and environment-friendly, and provides a brand new thought for the high-efficiency synthesis of waterborne polyurethane.

Description of the drawings:

FIG. 1 is a schematic representation of the amine salt of a polyhydroxy sulfonic acid prepared in accordance with example 1 of the present invention;

FIG. 2 shows the results (EI-) of mass spectrometric detection of the amine salts of polyhydroxysulphonic acids obtained in example 1 of the present invention;

FIG. 3 shows the results of mass spectrometry (EI +) of the amine salt of polyhydroxysulfonic acid obtained in example 1 of the present invention.

Detailed Description

The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.

The term "prepared from …" as used herein is synonymous with "comprising". The terms "comprises," "comprising," "includes," "including," "has," "having," "contains," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

The conjunction "consisting of …" excludes any unspecified elements, steps or components. If used in a claim, the phrase is intended to claim as closed, meaning that it does not contain materials other than those described, except for the conventional impurities associated therewith. When the phrase "consisting of …" appears in a clause of the subject matter of the claims rather than immediately after the subject matter, it defines only the elements described in the clause; other elements are not excluded from the claims as a whole.

When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.

The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. "optional" or "any" means that the subsequently described event or events may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification and claims, is intended to modify a quantity, such that the invention is not limited to the specific quantity, but includes portions that are literally received for modification without substantial change in the basic function to which the invention is related. Accordingly, the use of "about" to modify a numerical value means that the invention is not limited to the precise value. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In the present description and claims, range limitations may be combined and/or interchanged, including all sub-ranges contained therein if not otherwise stated.

In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the stated number clearly indicates that the singular form is intended.

In order to solve the above problems, a first aspect of the present invention provides a method for preparing an amine salt of a polyhydroxy sulfonic acid, comprising the steps of:

(1) preparing polyhydroxy sulfonic acid;

(2) reacting polyhydroxy sulfonic acid with tertiary amine compound to obtain polyhydroxy sulfonic acid amine salt.

In some preferred embodiments, the polyhydroxysulfonic acid is an alkanesulfonic acid having a hydroxyl number of 1 to 4.

In some preferred embodiments, the polyhydroxysulfonic acid is an alkanesulfonic acid having a hydroxyl number of 2; wherein the number of carbon atoms among carbon atoms connected with 2 hydroxyl groups is n, and n is more than or equal to 0 and less than or equal to 6.

More preferably, the structural general formula of the polyhydroxysulfonic acid is

Wherein Ra, Rb and Rc are independent of each other and are selected from one of hydrogen, lower alkyl and hydroxyalkyl; ra, Rb and Rc contain 2 hydroxyl groups.

In some preferred embodiments, the tertiary amine compound has a surface tension of 10 to 50dyne/cm and a boiling point of 35 to 126 ℃.

In some preferred embodiments, the amine salt of a polyhydroxy sulfonic acid has the structural formula

Wherein R is₁、R₂、R₃Independently of each other, are selected from the group consisting of alkyl, aryl, cycloalkyl, and combinations thereof.

In some preferred embodiments, the alkanesulfonic acid having a hydroxyl number of 2 is prepared by:

the first step is as follows: preparing alkanesulfonate with the hydroxyl number of 2;

the second step is that: acidifying the alkane sulfonate with the hydroxyl number of 2 to obtain a crude material;

the third step: and purifying the crude material to obtain the alkane sulfonic acid finished product with the hydroxyl number of 2.

In some preferred embodiments, the first step is specifically, mixing and reacting C2-C6 alkylene glycol with bisulfite in an aqueous medium to obtain alkanesulfonate with 2 hydroxyl groups.

In some preferred embodiments, the first step is specifically to mix and react halogenated hydroxysulfonic acid with strong base and weak acid salt in an aqueous medium to obtain alkane sulfonate with 2 hydroxyl groups.

In some preferred embodiments, in the first step, the pH of the reactants is controlled to be always maintained at 6.5 to 7.5 using a pH adjuster.

In some preferred embodiments, in the second step, an alkanesulfonic acid having a hydroxyl number of 2 is acidified with a strong acid; the strong acid comprises HClO₄，HI，H₂SO₄，HBr，HCl，HNO₃，HIO₃At least one of (1).

In some preferred embodiments, the third purification step is to put the crude material into a material separation device to remove low boiling point impurities, so as to obtain a finished product of alkanesulfonic acid with a hydroxyl number of 2.

In some preferred embodiments, the material separation device is a thin film evaporator and a molecular distillation device; further preferably, the third step is specifically that the material is introduced into a thin film evaporator to separate a low boiling point component and a high boiling point component; introducing the high boiling point component into a molecular distillation device, and collecting the heavy component, namely the alkane sulfonic acid finished product with the hydroxyl number of 2.

Further preferably, the working temperature of the thin film evaporator is 80-120 ℃, and the vacuum degree is 1-10 mBar.

Further preferably, the working temperature of the molecular distillation device is 80-150 ℃, and the vacuum degree is 0.001-1 mBar.

In some preferred embodiments, the step (2) is specifically: mixing polyhydroxy sulfonic acid prepared in the step (1) and ethanol according to a volume ratio of 1: 1-5, then dropwise adding a tertiary amine compound with the same molar weight as that of the polyhydroxysulfonic acid, reacting until the pH value is 7 +/-0.5 to obtain a crude product, and performing molecular distillation on the crude product to remove ethanol to obtain a pure polyhydroxysulfonic acid amine salt.

The second aspect of the invention provides application of a preparation method of polyhydroxy sulfonic acid amine salt, and the polyhydroxy sulfonic acid amine salt is applied to preparation of waterborne polyurethane.

Although a mature system has been formed in foreign countries by adopting sulfonic acid chain extenders to synthesize polyurethane, the research of the sulfonic acid chain extenders in China is still in a groping stage. In the actual process of synthesizing polyurethane, the selection of the chain extender has important influence on the reaction activity, the controllability of the reaction process and the solid content and performance of the reaction product. Although common carboxylic acid type chain extenders (such as dimethylolpropionic acid, dimethylolbutyric acid and the like) on the market at present can prepare polyurethane products with good weather resistance, the common carboxylic acid type chain extenders need to be dissolved by a high-boiling point solvent for reuse when in use, have large negative effects on environment and human bodies, have poor stability in an acetone solvent, are sensitive to pH, and can cause saponification of a polyurethane main chain when a medium tends to be acidic; the solid content of the finally obtained polyurethane product is difficult to exceed 40 percent. For a sulfonic acid type chain extender, sodium sulfamate (for example, Yingchuang A95) is popular at present, the chain extender can increase the solid content of waterborne polyurethane to more than 50%, but has the defects that the chain extender does not contain a solvent, and a solvent such as acetone and the like is required to be added into a prepolymer in the synthesis process to reduce the viscosity of a reactant; and because the solubility of the polyurethane in an organic solvent is poor, the polyurethane needs to be stored in a form of aqueous solution, isocyanate and amino and water molecules in a chain extender react quickly in the emulsification process, the reaction process is difficult to control, the requirements on equipment and a process are extremely high, the quality fluctuation of a synthesized polyurethane product is large, and even the gel condition occurs.

According to the invention, a large number of experiments prove that the polyhydroxysulfonic acid amine salt is generated by the reaction of the alkanesulfonic acid with the hydroxyl number of 2 and the tertiary amine compound, so that the defect that the chain extender for the waterborne polyurethane in the prior art cannot give consideration to both solid content and reaction controllability is overcome. On one hand, the polyhydroxy sulfonic acid amine salt synthesized by the method is in a liquid state, can serve as the dual identities of a chain extender and a solvent in the process of synthesizing polyurethane, and does not need to additionally add the solvent; on the other hand, the polyhydroxy sulfonic acid amine salt synthesized by the method is beneficial to the subsequent polyurethane reaction, the reaction process is stable and controllable, the solvent metering reaction is not needed in the whole process, the molecular structure of the formed polyurethane is easy to design, and the feasibility and the accurate controllability of the polyurethane synthesis are improved. Most importantly, the solid content of polyurethane formed by the cross-linking reaction of the synthesized polyhydroxy sulfonic acid amine salt, the polyol polymer and the isocyanate can reach about 60 percent, and the technical synthesis of the high-solid-content aqueous polyurethane is realized.

In the process of preparing the polyhydroxy sulfonic acid amine salt, the alkane sulfonate with 2 hydroxyl groups is acidified by gaseous strong acid, so that the residue of metal cations in a product system is reduced; and further purifying by using a material separation device, particularly purifying the crude material by using a thin film evaporator and a molecular distillation device in sequence, so that the crude material can be effectively separated from hydrogen chloride and water in a product within short retention time, and finally the obtained polyhydroxy sulfonic acid amine salt has high purity and low water content, and can meet the requirement of stable and smooth follow-up polyurethane reaction. The invention makes up the blind zone of the sulfonate amine salt type chain extender in the polyurethane chain extender technology, and has profound significance for the development of novel environment-friendly materials and the production of large-scale polyurethane.

Examples

In order to better understand the above technical solutions, the following detailed descriptions will be provided with reference to specific embodiments. It should be noted that the following examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and that the insubstantial modifications and adaptations of the present invention by those skilled in the art based on the above disclosure are still within the scope of the present invention. In addition, the raw materials are commercially available and the extraction methods of the extract are all conventional extraction methods, if not otherwise specified.

Example 1.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which comprises the following specific steps:

(1) preparing polyhydroxy sulfonic acid;

(2) mixing polyhydroxy sulfonic acid and tertiary amine compound according to a molar ratio of 1: 1, mixing and reacting until the pH value is 6.5-7.5 to obtain the polyhydroxy sulfonic acid amine salt.

The preparation of the polyhydroxy sulfonic acid is specifically as follows:

the first step is as follows: preparing polyhydroxy sulfonate: adding sodium bisulfite into water, stirring until the sodium bisulfite is completely dissolved, then adding a sodium hydroxide aqueous solution until the pH value is 7, then adding 1, 4-butylene glycol, reacting for 3 hours at 40 ℃, and adding dilute hydrochloric acid to control the pH value to 7 in the reaction process; to obtain polyhydroxy sulfonic acid (1, 4-dihydroxy butane-2-sodium sulfonate). The weight ratio of the sodium bisulfite to the 1, 4-butylene glycol to the water is 1.4: 2.2: 1.

the second step is that: acidifying polyhydroxy sulfonic acid to obtain a crude material: introducing hydrogen chloride gas into the 1, 4-dihydroxy butane-2-sodium sulfonate at the speed of 3.5L/min, reacting until no solid matter is separated out, and filtering the solid matter to obtain filtrate, namely the crude material.

The third step: purifying the crude material to obtain a polyhydroxy sulfonic acid finished product: introducing the material into an enamel film evaporator, and separating a low-boiling-point component and a high-boiling-point component; introducing the high boiling point component into a short-path molecular distillation device, and collecting the heavy component to obtain the polyhydroxy sulfonic acid finished product (1, 4-dihydroxy butane-2-sulfonic acid).

The working temperature of the enamel film evaporator is 105 ℃, and the vacuum degree is 10 mBar; the working temperature of the short-path molecular distillation device is 135 ℃, and the vacuum degree is 0.01 mBar.

The tertiary amine compound is triethylamine (surface tension 23.4dyne/cm, boiling point 89.5 ℃), namely the structural formula of the polyhydroxy sulfonic acid amine salt is shown in the specificationWherein Ra is CH₂OH, Rb is (CH)₂)₂OH and Rc are H; r₁、R₂、R₃Are all C₂H₅。

The step (2) is specifically as follows: mixing polyhydroxy sulfonic acid prepared in the step (1) and ethanol according to a volume ratio of 1: 1, uniformly mixing, then dropwise adding a tertiary amine compound with the same molar weight as the polyhydroxysulfonic acid, reacting until the pH value is 7 +/-0.5 to obtain a crude product, and performing molecular distillation on the crude product to remove ethanol to obtain a pure polyhydroxysulfonic acid amine salt.

Example 2.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which comprises the following specific steps:

(1) preparing polyhydroxy sulfonic acid;

(2) mixing polyhydroxy sulfonic acid and tertiary amine compound according to a molar ratio of 1: 1, and reacting for 1h at 26 ℃ to obtain the polyhydroxy sulfonic acid amine salt.

The preparation of the polyhydroxy sulfonic acid is specifically as follows:

the first step is as follows: preparing polyhydroxy sulfonate: sequentially adding 1-chloro-2-hydroxy sodium propanesulfonate, anhydrous sodium carbonate and water into a reaction vessel, stirring and refluxing at 88 ℃ for 5.5h to obtain the 1, 2-dihydroxy-sodium propanesulfonate. The weight ratio of the 1-chlorine-2-hydroxyl sodium propanesulfonate, the anhydrous sodium carbonate and the water is 5.9: 1.6: 10.

the second step is that: acidifying polyhydroxy sulfonic acid to obtain a crude material: introducing hydrogen chloride gas into the 1, 4-dihydroxy butane-2-sodium sulfonate at the speed of 3.5L/min, reacting until no solid matter is separated out, and filtering the solid matter to obtain filtrate, namely the crude material.

The third step: purifying the crude material to obtain a polyhydroxy sulfonic acid finished product: introducing the material into an enamel film evaporator, and separating a low-boiling-point component and a high-boiling-point component; introducing the high boiling point component into a short-path molecular distillation device, and collecting the heavy component to obtain the polyhydroxy sulfonic acid finished product (1, 2-dihydroxy-propanesulfonic acid).

The working temperature of the enamel film evaporator is 105 ℃, and the vacuum degree is 10 mBar; the working temperature of the short-path molecular distillation device is 135 ℃, and the vacuum degree is 0.01 mBar.

The tertiary amine compound is triethylamine (surface tension 23.4dyne/cm, boiling point 89.5 ℃), namely the structural formula of the polyhydroxy sulfonic acid amine salt is shown in the specificationWherein Ra is (HO) CH₂CH₂OH, Rb and Rc are all H; r₁、R₂、R₃Are all C₂H₅。

The step (2) is specifically as follows: mixing polyhydroxy sulfonic acid prepared in the step (1) and ethanol according to a volume ratio of 1: 1, uniformly mixing, then dropwise adding a tertiary amine compound with the same molar weight as the polyhydroxysulfonic acid, reacting until the pH value is 7 +/-0.5 to obtain a crude product, and performing molecular distillation on the crude product to remove ethanol to obtain a pure polyhydroxysulfonic acid amine salt.

Example 3.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which is the same as the embodiment 2 in specific; the difference is that the working temperature of the enamel film evaporator is 95 ℃, and the vacuum degree is 10 mBar.

Example 4.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which is the same as the embodiment 2 in specific; the difference is that the working temperature of the short-path molecular distillation device is 115 ℃, and the vacuum degree is 0.01 mBar.

Comparative example 1.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which is the same as the embodiment 2 in specific; the difference is that the second step is to acidify the polyhydroxy sulfonic acid to obtain a crude material: adding a concentrated hydrochloric acid aqueous solution with the mass fraction of 37% into 1, 4-dihydroxy butane-2-sodium sulfonate, reacting until no solid matter is separated out, and filtering the solid matter to obtain a filtrate, namely a coarse material.

Comparative example 2.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which is the same as the embodiment 2 in specific; the difference lies in that the third step: purifying the crude material to obtain a polyhydroxy sulfonic acid finished product: and introducing the material into a vacuum rotary evaporator, and collecting heavy components to obtain the polyhydroxy sulfonic acid finished product (1, 2-dihydroxy-propanesulfonic acid). The working temperature of the vacuum rotary evaporator is 105 ℃, and the vacuum degree is 10 mBar.

Comparative example 3.

The embodiment provides a preparation method of polyhydroxy sulfonic acid amine salt, which is the same as the embodiment 2 in specific; the difference lies in that the third step: purifying the crude material to obtain a polyhydroxy sulfonic acid finished product: introducing the material into a short-path molecular distillation device, collecting heavy components, introducing the heavy components into an enamel film evaporator, and collecting high-boiling-point components; the high boiling point component is polyhydroxy sulfonic acid finished product (1, 2-dihydroxy-propane sulfonic acid).

Performance test method

Water content:

the amine salts of polyhydroxysulfonic acids obtained in examples 1 to 4 and comparative examples 1 to 3 were sampled and the water content of the samples was measured by a Karl Fischer moisture analyzer; each sample was measured in duplicate and averaged 3 times.

Purity:

determination of sodium impurity content C in sample by referring to JY/T015-_Na(in%) reference to BS EN 14582:2016 for determination of chlorine impurity content C_Cl(unit is%)_l(ii) a Definition of sample purity C_x＝1-(C_Na+C_Cl)，C_xHigh purity of more than or equal to 99.8 percent of sample C_xIn the purity of the sample between 97-99.8% (without end points), C_xLess than or equal to 97 percent is low in purity of the sample; each sample was measured in duplicate and averaged 3 times.

Solid content:

preparing aqueous polyurethane emulsion by taking the polyhydroxy sulfonic acid amine salt prepared in examples 1-4 and comparative examples 1-3 as a sample; the preparation method comprises the following steps: 200g of polypropylene glycol (average molecular weight 1000, purchased from Nantong, high Key), 89g of IPDI, 0.05g of dibutyltin dilaurate were added into a three-necked flask, and the mixture was reacted at 90 ℃ for 3 hours; then adding a polyhydroxy sulfonic acid amine salt sample, reacting until the NCO content is 4%, adding 200g of acetone, uniformly stirring, adding the mixture into a proper amount of water, emulsifying for 0.5h, and removing the acetone under reduced pressure to obtain an aqueous polyurethane emulsion; the solid content of the aqueous polyurethane emulsion was determined gravimetrically.

The molar ratio of the polyhydroxy sulfonic acid amine salt sample to IPDI is 0.12: 1.

performance test data

TABLE 1 Performance test results

	Has water content of%	Purity of	Solid content%
				Example 1	0.2	Height of	61.5
Example 2	0.2	Height of	60.3
				Example 3	0.3	Height of	62.1
Example 4	0.3	Height of	60.8
				Comparative example 1	0.3	Is low in	52.7
Comparative example 2	5.1	Is low in	46.8
				Comparative example 3	0.4	Good wine	58.9

Finally, it is pointed out that the foregoing examples are illustrative only, serving to explain some of the characteristics of the process according to the invention. The appended claims are intended to claim as broad a scope as is contemplated, and the examples presented herein are merely illustrative of selected implementations in accordance with all possible combinations of examples. Accordingly, it is applicants' intention that the appended claims are not to be limited by the choice of examples illustrating features of the invention. Also, where numerical ranges are used in the claims, subranges therein are included, and variations in these ranges are also to be construed as possible being covered by the appended claims.