Hydroxyl-terminated sulfonic acid type hydrophilic chain extender and preparation method thereof

Abstract

The preparation method comprises the following steps: adding a sodium hydrogen sulfite aqueous solution and a catalyst into a reaction container, heating, dropwise adding resorcinol diglycidyl ether after the temperature reaches a set value, titrating with an iodine standard solution until the content of sodium hydrogen sulfite is basically unchanged, and ending the reaction. And carrying out reduced pressure suction filtration on the reaction solution to obtain a product, washing the product with ethyl acetate and ethanol, removing resorcinol diglycidyl ether, drying to obtain a crude product, dissolving the crude product in a hydrochloric acid solution, heating in a constant temperature water bath, evaporating SO2, continuously adding a NaOH alcoholic solution, adjusting the pH to alkalescence, filtering to obtain a solid, and drying to obtain the resorcinol diglycidyl ether. According to the invention, sodium hydrogen sulfite and epoxy are subjected to ring-opening reaction to generate the novel hydrophilic chain extender with hydroxyl and sulfonic acid functional groups. Compared with a traditional production mode, the method is simple in reaction condition, rapid in reaction and high in conversion rate, and has a great prospect in hydrophilic chain extension application.

Description

Technical Field

[0001] The invention relates to the technical field of hydrophilic chain extenders, and in particular to a hydroxyl-terminated sulfonic acid type hydrophilic chain extender and a preparation method thereof. Technical Background

[0002] Polymer materials play a very important role in people's production and life. Waterborne polyurethane is widely used in coatings, adhesives, leather, medicine and other fields. Hydrophilic chain extender is an important functional monomer for synthesizing polymer materials, which is particularly important in the preparation of waterborne polyurethane. The introduction of some characteristic functional groups on the chain extender can affect the performance of waterborne polyurethane. Hydrophilic chain extender can make waterborne polyurethane have good dispersibility or self-emulsification properties.

[0003] Currently, aminosulfonates are mostly used as additives for waterborne polyurethane synthesis on the market. Due to the high production cost, the price of aminosulfonate hydrophilic chain extenders is usually high, which may increase the production cost of the product. At the same time, during the production and use process, if not handled properly, aminosulfonate hydrophilic chain extenders may have a negative impact on the environment, especially when discharging and treating wastewater.

[0004] Therefore, the synthesis and development of new hydrophilic chain extenders has become a research hotspot. Summary of the invention

[0005] In view of the above shortcomings, the present invention uses sodium bisulfite and epoxy to carry out a ring-opening reaction to generate a new hydrophilic chain extender with hydroxyl and sulfonic acid functional groups. Compared with the traditional production method, the reaction conditions are simple, the reaction is rapid, the conversion rate is high, and it has great prospects in the application of hydrophilic chain extension.

[0006] In order to achieve the purpose of the present invention, the present invention adopts Figure 4 The technical solution shown:

[0007] A method for preparing a hydroxyl-terminated sulfonic acid type hydrophilic chain extender comprises the following steps:

[0008] (1) adding a sodium bisulfite aqueous solution and a catalyst into a reaction container and heating the container for reaction;

[0009] (2) After the temperature reaches the set value, resorcinol diglycidyl ether is added dropwise, and at the same time, the sodium bisulfite content is titrated with an iodine standard solution until it remains substantially unchanged, and the reaction is terminated;

[0010] (3) filtering the reaction solution under reduced pressure to obtain the product, washing the product with ethyl acetate and ethanol, and drying to obtain a crude product;

[0011] (4) The crude product is dissolved in a hydrochloric acid solution and mixed with a magnetic stirrer, and heated in a constant temperature water bath. After SO2 is evaporated, an alcoholic NaOH solution is added to the solution, and the pH is adjusted to a weak alkaline state. The solid is filtered and dried to obtain a terminal hydroxy sulfonic acid type hydrophilic chain extender.

[0012] Furthermore, the catalyst in step (1) is triethylamine; the amount of the catalyst used is 2.02 to 5.77 parts by weight.

[0013] Furthermore, the sodium bisulfite aqueous solution in step (1) is prepared by mixing 23.67 to 27.80 parts of sodium bisulfite with 35.50 to 41.69 parts of water.

[0014] Furthermore, in step (1), the temperature is raised to 60°C.

[0015] Furthermore, in step (2), the temperature reaches a set value of 60°C.

[0016] Furthermore, the amount of resorcinol diglycidyl ether used in step (2) is 25.90 to 34.65 parts by weight.

[0017] Furthermore, the magnetic stirring time in step (4) is 20 min.

[0018] Furthermore, the constant temperature water bath in step (4) is heated to 50°C.

[0019] Furthermore, the concentration of the NaOH alcohol solution in step (4) is 0.1 mol / L.

[0020] The invention also discloses a hydroxyl-terminated sulfonic acid type hydrophilic chain extender prepared according to any of the above preparation methods.

[0021] The beneficial effects of the present invention are:

[0022] 1. The present invention utilizes sodium bisulfite and epoxy to undergo a ring-opening reaction to generate a novel hydrophilic chain extender with hydroxyl and sulfonic acid functional groups. Compared with the traditional production method, the reaction conditions are simple, the reaction is rapid, and the conversion rate is high, which has great prospects in the application of hydrophilic chain extension.

[0023] 2. The raw materials used in the present invention are sodium bisulfite and resorcinol diglycidyl ether to react to synthesize a new sulfonic acid type polyol, which can be used as a hydrophilic chain extender in the synthesis of waterborne polyurethane.

[0024] 3. Sulfonic acid polyol is a new type of polyol obtained by epoxy ring opening. At present, our main application direction is to use it as a hydrophilic chain extender for waterborne polyurethane. It has broad application prospects in the fields of coatings, elastomers, adhesives, etc., and provides a variety of functional material options for different industries. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is the infrared spectrum test diagram of the crude product of the terminal hydroxyl sulfonic acid type hydrophilic chain extender;

[0026] Figure 2 This is the infrared spectrum test diagram of the pure extract of the terminal hydroxyl sulfonic acid type hydrophilic chain extender;

[0027] Figure 3 This is the thermogravimetric analysis diagram of the purified product of the hydroxyl-terminated sulfonic acid type hydrophilic chain extender;

[0028] Figure 4 This is the reaction process of the present invention. DETAILED DESCRIPTION

[0029] The present invention is described in detail below through examples. It is necessary to point out that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments based on the contents of the present invention, which still fall within the scope of protection of the present invention.

[0030] Example 1

[0031] A kind of hydroxyl-terminated sulfonic acid type hydrophilic chain extender and preparation method thereof

[0032] (1) A reaction vessel including a thermometer, a condenser and a stirring device was added to the reaction vessel. A mixed solution of 26.97 g of sodium bisulfite and 40.60 g of water and 3.94 g of catalyst triethylamine were mixed and the temperature was raised to 60°C.

[0033] (2) After the temperature reaches the set value of 60°C, 27.64 g of resorcinol diglycidyl ether is added dropwise to the reactor at a steady rate using a dropper. The reaction is terminated when the sodium bisulfite content is titrated with a standard iodine solution until it remains essentially unchanged.

[0034] (3) The reaction solution is filtered under reduced pressure to obtain the product, and the residual resorcinol diglycidyl ether is washed with ethyl acetate, and the residual ethyl acetate and resorcinol diglycidyl ether are further washed with ethanol, and the ethanol is dried to be removed, and the process is repeated 2 to 3 times to obtain a crude product. The crude product is dissolved in a hydrochloric acid solution, stirred on a magnetic stirrer for 20 minutes, heated to 50°C in a water bath, and after SO2 is evaporated, 0.1 mol / L NaOH alcohol solution is continued to be added to the solution, the pH is adjusted to weak alkalinity, and the solid is filtered to obtain and heated in an oven to obtain a terminal hydroxyl sulfonic acid type hydrophilic chain extender.

[0035] Example 2

[0036] A kind of hydroxyl-terminated sulfonic acid type hydrophilic chain extender and preparation method thereof

[0037] (1) A reaction vessel including a thermometer, a condenser and a stirring device was added to the reaction vessel. A mixed solution of 27.80 g of sodium bisulfite and 43.34 g of water and 3.69 g of catalyst triethylamine were mixed and the temperature was raised to 60°C.

[0038] (2) After the temperature reaches the set value of 60°C, 25.90 g of resorcinol diglycidyl ether is added dropwise to the reactor at a steady rate using a dropper. The sodium bisulfite content is titrated with an iodine standard solution until it remains essentially unchanged, and the reaction is terminated.

[0039] (3) The reaction solution is filtered under reduced pressure to obtain the product, and the residual resorcinol diglycidyl ether is washed with ethyl acetate, and the residual ethyl acetate and resorcinol diglycidyl ether are further washed with ethanol, and the ethanol is dried to be removed, and the process is repeated 2 to 3 times to obtain a crude product. The crude product is dissolved in a hydrochloric acid solution, stirred on a magnetic stirrer for 20 minutes, heated to 50°C in a water bath, and after SO2 is evaporated, 0.1 mol / L NaOH alcohol solution is continued to be added to the solution, the pH is adjusted to weak alkalinity, and the solid is filtered to obtain and heated in an oven to obtain a terminal hydroxyl sulfonic acid type hydrophilic chain extender.

[0040] Example 3

[0041] A kind of hydroxyl-terminated sulfonic acid type hydrophilic chain extender and preparation method thereof

[0042] (1) A reaction vessel including a thermometer, a condenser and a stirring device was added to the reaction vessel. A mixed solution of 26.03 g of sodium bisulfite and 37.86 g of water and 4.23 g of catalyst triethylamine were mixed and the temperature was raised to 60°C.

[0043] (2) After the temperature reaches the set value of 60°C, 29.64 g of resorcinol diglycidyl ether is added dropwise to the reactor at a steady rate using a dropper. The sodium bisulfite content is titrated with an iodine standard solution until it remains essentially unchanged, and the reaction is terminated.

[0044] (3) The reaction solution is filtered under reduced pressure to obtain the product, and the residual resorcinol diglycidyl ether is washed with ethyl acetate, and the residual ethyl acetate and resorcinol diglycidyl ether are further washed with ethanol, and the ethanol is dried to be removed, and the process is repeated 2 to 3 times to obtain a crude product. The crude product is dissolved in a hydrochloric acid solution, stirred on a magnetic stirrer for 20 minutes, heated to 50°C in a water bath, and after SO2 is evaporated, 0.1 mol / L NaOH alcohol solution is continued to be added to the solution, the pH is adjusted to weak alkalinity, and the solid is filtered to obtain and heated in an oven to obtain a terminal hydroxyl sulfonic acid type hydrophilic chain extender.

[0045] Test Example 1

[0046] Experimental data of hydroxyl-terminated sulfonic acid type hydrophilic chain extender:

[0047] Example 2 Infrared spectrum test of hydroxyl-terminated sulfonic acid type hydrophilic chain extender Figure 1 shown.

[0048] In the spectrum of the reactant resorcinol diglycidyl ether, 909.16 cm -1 The characteristic peak of epoxy group at has disappeared. Figure 1 In the spectrum of the crude product, at 3500-3400 cm -1 A strong and broad hydroxyl characteristic absorption peak appeared at 1210-1190 cm -1 、1050±10cm -1 、535~525cm -1 Strong characteristic peaks of sulfonic acid groups appeared in the range, indicating that sodium bisulfite and resorcinol diglycidyl ether underwent the expected ring-opening reaction to obtain the target product.

[0049] Example 2 The spectrum of the purified product of the hydroxyl-terminated sulfonic acid type hydrophilic chain extender is as follows Figure 2 As shown. Figure 1 The spectra of the crude product are highly consistent, and it can be considered that the purification process is successful and the product has achieved the expected purity and structure.

[0050] Example 2 Thermogravimetric analysis of the purified product of terminal hydroxy sulfonic acid type hydrophilic chain extender Figure 3 As shown. The purified product underwent an obvious decomposition reaction during the heating process. The first decomposition starting temperature was about 78.4°C, the end temperature was about 183.3°C, the mass change was 1.71%, and the decomposition reaction still occurred at 295.1°C, indicating that there were some impurity melting absorption peaks in the purified product; at 295.1°C, the decomposition reaction of the purified product was the most intense, indicating that this temperature was the key reaction temperature point; the residual mass was 94.32%, indicating that the reaction was relatively thorough and the product stability was good.

[0051] Example 2 The reaction process of the hydroxy-terminated sulfonic acid type hydrophilic chain extender is as follows Figure 4 shown.

[0052] The embodiments described above are part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

Claims

1. A method for preparing a hydroxy-terminated sulfonic acid type hydrophilic chain extender, comprising: (1) adding a sodium bisulfite aqueous solution and a catalyst into a reaction container and heating the container for reaction; (2) After the temperature reaches the set value, resorcinol diglycidyl ether is added dropwise, and the sodium bisulfite content is titrated with an iodine standard solution until it remains substantially unchanged, and the reaction is terminated; (3) filtering the reaction solution under reduced pressure to obtain the product, washing the product with ethyl acetate and ethanol, and drying to obtain a crude product; (4) The crude product is dissolved in a hydrochloric acid solution and mixed with a magnetic stirrer, and heated in a constant temperature water bath. After SO2 is evaporated, an alcoholic NaOH solution is added to the solution, and the pH is adjusted to a weak alkaline state. The solid is filtered and dried to obtain a terminal hydroxy sulfonic acid type hydrophilic chain extender.

2. The preparation method according to claim 1, wherein: The catalyst in step (1) is triethylamine; The catalyst is used in an amount of 2.02 to 5.77 parts by weight.

3. The preparation method according to claim 1, wherein: The sodium bisulfite aqueous solution in step (1) is prepared by mixing 23.67 to 27.80 parts of sodium bisulfite with 35.50 to 41.69 parts of water.

4. The preparation method according to claim 1, wherein: In step (1), the temperature is raised to 60°C.

5. The preparation method according to claim 1, wherein: In step (2), the temperature reaches a set value of 60°C.

6. The preparation method according to claim 1, wherein: The amount of resorcinol diglycidyl ether used in step (2) is 25.90 to 34.65 parts by weight.

7. The preparation method according to claim 1, wherein: The magnetic stirring time in step (4) is 20 min.

8. The preparation method according to claim 1, wherein: The constant temperature water bath in step (4) is heated to 50°C.

9. The preparation method according to claim 1, wherein: The concentration of the NaOH alcohol solution in step (4) is 0.1 mol / L.

10. A hydroxy-terminated sulfonic acid type hydrophilic chain extender prepared according to the preparation method according to any one of claims 1 to 9.

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