Polyether glycol and preparation method thereof, and waterborne polyurethane emulsion

Abstract

The invention discloses polyether glycol and a preparation method thereof, and a waterborne polyurethane emulsion. The preparation method comprises the following steps that: polyether monoalcohol R-(O-CH2-CH2-)n-OH reacts with a halogenating reagent to prepare halogen-terminated polyether R-(O-CH2-CH2-)n-X, then the halogen-terminated polyether R-(O-CH2-CH2-)n-X reacts with a compound defined in the specification to obtain end-capped polyether defined in the specification. In the refining process, an adsorbent and an auxiliary agent cooperate, the material adsorption amount in a filter cake is reduced, and the product loss is further reduced; the end-capped polyether is subjected to a ring-opening reaction in the presence of an acid catalyst to obtain a product polyether glycol defined in the specification, wherein n is 3-220, preferably 14-87, and the molecular weight distribution is 1.01-1.25, preferably 1.05-1.15. The preparation process is simple and efficient, the raw materials are low in cost and wide in source, and the industrial prospect is good. The polyether glycol is used for preparing the waterborne polyurethane emulsion and has the beneficial effect of reducing the viscosity.

Description

technical field

[0001] The invention relates to the field of polyether, in particular to a polyether diol and a preparation method thereof. Background technique

[0002] Emulsifiers are surface active substances that can make two immiscible liquids form a stable solution dispersion system under certain conditions. It is one of the main components in the preparation of water-based polyurethane coatings. Although its dosage is small, it plays a decisive role in the process of forming water-based polyurethane emulsion. Traditional emulsion polymerization uses anionic surfactants and nonionic surfactants as emulsifiers. Anionic surfactants include sulfonates, sulfates, carboxylates, phosphates, etc.; nonionic surfactants include polyoxyethylene Ether type, fatty acid polyol. However, these traditional emulsifiers can only gather on the surface of latex particles through physical adsorption, and will eventually remain in the product, affecting its performance.

[0003] In orde...

Examples

Embodiment 1

[0058] (1) Preparation of terminal halogen substituted polyether

[0059] Weigh 150g of MPEG5000, dissolve it in 200g of dichloromethane, and under stirring at room temperature, feed 2.97g of phosgene within 2 hours. After reacting for 1 hour, keep the absolute pressure at 2kpa, raise the temperature to remove the solvent, discharge 150.5g of wax, and measure the hydroxyl Value<1mgKOH / g.

[0060] (2) Preparation of end-capped polyether

[0061] Weigh 5.20g compound I (prepared with reference to CN103193972A) was added into a three-necked flask, heated to 60°C, and then 1.62g of sodium methoxide was reacted at 60°C for 1 hour under the protection of nitrogen, then heated to 80°C, degassed at 2kpa for 3h, and added the melted terminal halogen Replace polyether, then continue to react at 80°C for 6 hours, add 30% phosphoric acid aqueous solution to adjust the pH to 8, then add 1.2g activated clay and 0.16g butyldiaminetetraacetic acid diammonium zinc (BTTA-NZ), after dehydrati...

Embodiment 2

[0065] (1) Preparation of terminal halogen substituted polyether

[0066] Weigh 150g of MPEG4000, dissolve it in 300g of chlorobenzene, feed 3.71g of phosgene within 2 hours under stirring at -5°C, continue the reaction for 1 hour, keep an absolute pressure of 2kpa, raise the temperature to remove the solvent, cool down and discharge the material, and measure the hydroxyl value< 1mgKOH / g.

[0067] (2) Preparation of end-capped polyether

[0068] Weigh 10.4g compound I Add it into a three-necked flask, raise the temperature to 60°C, and then heat 5.2g of potassium methylate under the protection of nitrogen, heat it at 60°C for 1 hour, heat it up to 80°C, degas it at 2kpa for 3 hours, add the melted halogen-substituted polyether, and then Continue the reaction at 80°C for 6 hours, add 30% phosphoric acid aqueous solution to adjust the pH to 8, then add 1g of silica gel and 0.15g of zinc diammonium butyldiamine tetraacetate (BTTA-NZ), after dehydration, filter through plate an...

Embodiment 3

[0075] Embodiment 3: preparation method of aqueous polyurethane emulsion

[0076] Add 120 grams of polyethylene glycol (molecular weight 6000), 120 grams of polyether diol prepared in Example 1 and 20 grams of polytetrahydrofuran diol (number average molecular weight 2000) into the reactor, dehydrate at 120 ° C for 1 hour, and cool down to 70 ℃, add 0.32g of dibutyltin dilaurate and 10.4g of tetramethylxylylene diisocyanate under stirring, after stirring for 5 hours, measure the NCO to be 0.60%, add 750 grams of water, and stir vigorously for 10 minutes to obtain waterborne polyurethane The dispersion has a measured viscosity of 5267cp@25°C and a solid content of 27.2%.

technical field

[0001] The invention relates to the field of polyether, in particular to a polyether diol and a preparation method thereof. Background technique

[0002] Emulsifiers are surface active substances that can make two immiscible liquids form a stable solution dispersion system under certain conditions. It is one of the main components in the preparation of water-based polyurethane coatings. Although its dosage is small, it plays a decisive role in the process of forming water-based polyurethane emulsion. Traditional emulsion polymerization uses anionic surfactants and nonionic surfactants as emulsifiers. Anionic surfactants include sulfonates, sulfates, carboxylates, phosphates, etc.; nonionic surfactants include polyoxyethylene Ether type, fatty acid polyol. However, these traditional emulsifiers can only gather on the surface of latex particles through physical adsorption, and will eventually remain in the product, affecting its performance.

[0003] In orde...

Examples

Embodiment 1

[0058] (1) Preparation of terminal halogen substituted polyether

[0059] Weigh 150g of MPEG5000, dissolve it in 200g of dichloromethane, and under stirring at room temperature, feed 2.97g of phosgene within 2 hours. After reacting for 1 hour, keep the absolute pressure at 2kpa, raise the temperature to remove the solvent, discharge 150.5g of wax, and measure the hydroxyl Value<1mgKOH / g.

[0060] (2) Preparation of end-capped polyether

[0061] Weigh 5.20g compound I (prepared with reference to CN103193972A) was added into a three-necked flask, heated to 60°C, and then 1.62g of sodium methoxide was reacted at 60°C for 1 hour under the protection of nitrogen, then heated to 80°C, degassed at 2kpa for 3h, and added the melted terminal halogen Replace polyether, then continue to react at 80°C for 6 hours, add 30% phosphoric acid aqueous solution to adjust the pH to 8, then add 1.2g activated clay and 0.16g butyldiaminetetraacetic acid diammonium zinc (BTTA-NZ), after dehydrati...

Embodiment 2

[0065] (1) Preparation of terminal halogen substituted polyether

[0066] Weigh 150g of MPEG4000, dissolve it in 300g of chlorobenzene, feed 3.71g of phosgene within 2 hours under stirring at -5°C, continue the reaction for 1 hour, keep an absolute pressure of 2kpa, raise the temperature to remove the solvent, cool down and discharge the material, and measure the hydroxyl value< 1mgKOH / g.

[0067] (2) Preparation of end-capped polyether

[0068] Weigh 10.4g compound I Add it into a three-necked flask, raise the temperature to 60°C, and then heat 5.2g of potassium methylate under the protection of nitrogen, heat it at 60°C for 1 hour, heat it up to 80°C, degas it at 2kpa for 3 hours, add the melted halogen-substituted polyether, and then Continue the reaction at 80°C for 6 hours, add 30% phosphoric acid aqueous solution to adjust the pH to 8, then add 1g of silica gel and 0.15g of zinc diammonium butyldiamine tetraacetate (BTTA-NZ), after dehydration, filter through plate an...

Embodiment 3

[0075] Embodiment 3: preparation method of aqueous polyurethane emulsion

[0076] Add 120 grams of polyethylene glycol (molecular weight 6000), 120 grams of polyether diol prepared in Example 1 and 20 grams of polytetrahydrofuran diol (number average molecular weight 2000) into the reactor, dehydrate at 120 ° C for 1 hour, and cool down to 70 ℃, add 0.32g of dibutyltin dilaurate and 10.4g of tetramethylxylylene diisocyanate under stirring, after stirring for 5 hours, measure the NCO to be 0.60%, add 750 grams of water, and stir vigorously for 10 minutes to obtain waterborne polyurethane The dispersion has a measured viscosity of 5267cp@25°C and a solid content of 27.2%.

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