阅读说明：本技术 一种低成本水性胶黏剂及其制备方法 (Low-cost aqueous adhesive and preparation method thereof ) 是由 李海云 王永垒 江蓉 魏文静 朱梦泽 张雅文 于 2021-01-11 设计创作，主要内容包括：公开了一种低成本水性胶黏剂制备方法,其包括以质量份计的以下原料：糖蜜水溶液5-8份；丁二酸0.2-0.6份；十三烷二酸0.5-1份；丙酸6-10份；二甲苯1.5-3份；乙醇0.2-0.5份；水6-8份；分散剂0.05-0.15份；防腐剂0.005-0.01份；和催化剂。该水性胶黏剂利用制糖工业副产品糖蜜制备得到,成本低廉,最终产品具有3000-4000mPa·s的粘度,乳化的稳定性好,可用于作为纸塑包装材料的胶黏剂。(Discloses a preparation method of a low-cost aqueous adhesive, which comprises the following raw materials in parts by mass: 5-8 parts of molasses water solution; succinic acid 0.2-0.6 part; 0.5-1 part of tridecanedioic acid; 6-10 parts of propionic acid; 1.5-3 parts of dimethylbenzene; 0.2-0.5 part of ethanol; 6-8 parts of water; 0.05-0.15 part of dispersant; 0.005-0.01 part of preservative; and a catalyst. The aqueous adhesive is prepared from molasses which is a byproduct in the sugar industry, is low in cost, has the viscosity of 3000-4000mPa & s and good emulsification stability, and can be used as an adhesive for paper-plastic packaging materials.)

1. A preparation method of a low-cost aqueous adhesive comprises the following raw materials in parts by mass:

a catalyst.

2. The method of claim 1 wherein the aqueous molasses solution is an aqueous cane molasses solution having a solids content of 80 wt%.

3. The method of claim 1 wherein the dispersant is a mixture of polyanionic cellulose (PAC) and fatty alcohol-polyoxyethylene ether (AEO-9).

4. The method of claim 1 wherein the preservative is benzoic acid or sodium benzoate.

5. The method for preparing the low-cost aqueous adhesive as claimed in claim 1, wherein the catalyst is tetrabutyl titanate, and the dosage of the tetrabutyl titanate is 0.05-0.1% of the mass of the molasses aqueous solution.

6. The method of making the low cost aqueous adhesive of any of claims 1-5 further comprising the steps of:

A. adding the molasses water solution with the formula ratio into a reactor, heating to a first temperature, and performing reduced pressure dehydration;

B. after no obvious liquid is evaporated, closing the vacuum system, adding succinic acid, tridecanedioic acid, xylene and a catalyst according to the formula amount, and continuously heating to the boiling point of the xylene to carry out reflux water separation reaction;

C. when the acid value of the system mixture is less than 10mgKOH/g, adding propionic acid with the formula amount for carrying out end capping reaction, and then continuously carrying out reflux water diversion reaction at the boiling point of xylene;

D. when the hydroxyl value of the system mixture is less than 10mgKOH/g, vacuumizing, continuously heating to a second temperature, and removing the xylene solvent and unreacted propionic acid under reduced pressure;

E. stopping the vacuum system after no obvious substances are evaporated, cooling to room temperature, washing, removing the water phase by layering to obtain viscous liquid, and pumping into an emulsifying kettle;

G. and then adding ethanol, water, a dispersing agent and a preservative in a formula ratio into the emulsifying kettle, stirring and emulsifying for a period of time, and discharging after the emulsion is stable to obtain the aqueous adhesive.

7. The method as claimed in claim 6, wherein the first temperature is 110-120 ℃ and the second temperature is 145-150 ℃.

8. The method of claim 6 wherein the vacuum degree in step A or D is controlled to be between-0.095 MPa and-0.098 MPa.

9. The aqueous adhesive prepared by the preparation method of the aqueous adhesive according to claims 1-8.

10. The aqueous adhesive of claim 9 having a viscosity of 3000 and 4000mPa s, an acid number and a hydroxyl number of < 10 mgKOH/g.

Technical Field

The invention belongs to the technical field of adhesives, and particularly relates to a low-cost aqueous adhesive and a preparation method thereof.

Background

The aqueous adhesive is an environment-friendly adhesive prepared by using water as a solvent and using an aqueous high molecular compound as well as a dispersant and a cosolvent to replace a toxic organic solvent which pollutes the environment. The adhesive has the advantages of no toxicity, no pollution, no combustion, safe use, easy realization of clean production process and the like, and becomes the direction of environment-friendly adhesives which are mainly developed in China. However, the production cost of the aqueous adhesive is still high at present.

With the stricter environmental protection of the country, a certain pressure is brought to the comprehensive utilization of the byproducts. The cane molasses is a liquid byproduct generated in the process of preparing cane sugar, the yield is high at present, the cane molasses is mainly used as an additive of feed for fish culture and the like, the added value is low, related scientific research personnel also carry out a series of researches for improving the added value of the molasses, for example, ZL201510042701.6 is used in a cement grinding aid, but the cement grinding aid is not an auxiliary agent which is necessary for cement processing, and the using amount is not large, so that a product with a large using amount needs to be developed to improve the added value of the molasses. .

Therefore, in order to solve the technical problems, the invention provides a method for preparing an aqueous adhesive by using molasses, a sugar production byproduct, as a main raw material, and the aqueous adhesive prepared by the method.

Disclosure of Invention

In order to solve the technical problems, the invention provides a preparation method of a low-cost aqueous adhesive, which comprises the following raw materials in parts by mass:

wherein the molasses water solution is molasses water solution with solid content of 80 wt%, and the molasses is cane molasses.

The dispersing agent is a mixture of polyanionic cellulose and fatty alcohol-polyoxyethylene ether (AEO-9), wherein the mass ratio of the polyanionic cellulose (PAC) to the fatty alcohol-polyoxyethylene ether (AEO-9) is 1:1.5-2.5, and preferably 1:2.

Wherein the preservative is benzoic acid or sodium benzoate.

Wherein the catalyst is tetrabutyl titanate, and the dosage of the catalyst is 0.05-0.1% of the mass of the molasses aqueous solution.

The preparation method of the low-cost water-based adhesive further comprises the following steps:

A. adding the molasses water solution with the formula ratio into a reactor, heating to a first temperature, and performing reduced pressure dehydration;

B. after no obvious liquid is evaporated, closing the vacuum system, adding succinic acid, tridecanedioic acid, xylene and a catalyst according to the formula amount, and continuously heating to the boiling point of the xylene to carry out reflux water separation reaction;

C. when the acid value of the system mixture is less than 10mgKOH/g, adding propionic acid with the formula amount for carrying out end capping reaction, and then continuously carrying out reflux water diversion reaction at the boiling point of xylene;

D. when the hydroxyl value of the system mixture is less than 10mgKOH/g, vacuumizing, continuously heating to a second temperature, and removing the xylene solvent and unreacted propionic acid under reduced pressure;

E. stopping the vacuum system after no obvious substances are evaporated, cooling to room temperature, washing, removing the water phase by layering to obtain viscous liquid, and pumping into an emulsifying kettle;

G. and then adding ethanol, water, a dispersing agent and a preservative in a formula ratio into the emulsifying kettle, stirring and emulsifying for a period of time, and discharging after the emulsion is stable to obtain the aqueous adhesive.

Wherein, in the step A, the first temperature is 110-120 ℃.

Wherein, in the step A, the vacuum degree of the decompression dehydration is controlled to be-0.095 Mpa to-0.098 Mpa.

And in the step B and the step C, the dimethylbenzene is a water-carrying agent.

And D, wherein in the step D, the vacuum degree of the vacuum pumping is between-0.095 MPa and-0.098 MPa.

Wherein, in the step D, the second temperature is 145-150 ℃.

In the step E, the washing is to add water with the mass of 0.8-1.2 times of that of the molasses water solution to wash and remove residual propionic acid, catalyst and other impurities.

And G, rapidly stirring and emulsifying for 2-2.5h at room temperature.

The invention also provides the aqueous adhesive prepared by the preparation method of the aqueous adhesive.

Wherein the appearance of the aqueous adhesive is uniform emulsion liquid, and the aqueous adhesive has the viscosity of 3000-4000mPa & s, the acid value and the hydroxyl value of less than 10 mgKOH/g.

The beneficial technical effects of the invention are embodied in the following aspects:

1. the aqueous adhesive is prepared by reacting mainly by-products in the sugar industry, such as molasses, succinic acid, tridecanedioic acid, tetrabutyl titanate, propionic acid, xylene, a dispersing agent, a preservative, water, ethanol and the like, as raw materials. The finally obtained aqueous adhesive has an acid value and a hydroxyl value of less than 10mgKOH/g, good emulsification stability and outstanding bonding capability.

2. The aqueous adhesive and the preparation method realize comprehensive utilization of molasses which is a byproduct in the sugar industry, are low in cost, are moderate in viscosity, and good in storage stability and bonding performance, and can be used as an adhesive for paper-plastic packaging materials.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

A preparation method of a low-cost aqueous adhesive comprises the following raw materials in parts by mass:

wherein the sugar cane molasses water solution is a sugar cane molasses water solution with a solid content of 80 wt%.

Wherein the catalyst is tetrabutyl titanate, and the dosage of the tetrabutyl titanate is 0.1 percent of the mass of the cane molasses water solution.

Wherein the dispersing agent is a mixture of polyanionic cellulose (PAC) and fatty alcohol-polyoxyethylene ether (AEO-9), and the mass ratio of the polyanionic cellulose to the fatty alcohol-polyoxyethylene ether is 1: 2;

the preparation method further comprises the following steps:

A. adding the cane molasses water solution with the formula amount into a reaction kettle, heating to 110 ℃, and performing reduced pressure dehydration, wherein the vacuum degree is controlled to be-0.098 Mpa;

B. after no obvious liquid is evaporated, closing the vacuum system, adding succinic acid, tridecanedioic acid, xylene and tetrabutyl titanate according to the formula amount, and continuously heating to the boiling point of xylene as a water-carrying agent to perform reflux water diversion reaction;

C. when the acid value of the system mixture is less than 10mgKOH/g, adding propionic acid with the formula amount for carrying out end-capping reaction, and then continuing carrying out reflux water-splitting reaction at the boiling point of xylene with water;

D. when the hydroxyl value of the system mixture is less than 10mgKOH/g, starting a vacuum system, keeping the vacuum degree at-0.098 Mpa, continuously heating to 150 ℃, and removing the xylene solvent and unreacted propionic acid under reduced pressure;

E. stopping the vacuum system after no obvious substances are evaporated, cooling to room temperature, adding water with the mass of 0.8 times that of the cane molasses water solution, washing for one time to remove residual propionic acid, catalyst and other impurities, removing the water phase in a layering manner to obtain viscous liquid, and pumping the viscous liquid into an emulsifying kettle;

G. and then adding ethanol, water and a dispersing agent in a formula ratio into an emulsifying kettle, quickly stirring and emulsifying for 2 hours at room temperature, and discharging to obtain the aqueous adhesive after the emulsion stability meets the requirement.

Example 2

A preparation method of a low-cost aqueous adhesive comprises the following raw materials in parts by mass:

wherein the sugar cane molasses water solution is a sugar cane molasses water solution with a solid content of 80 wt%.

Wherein the catalyst is tetrabutyl titanate, and the dosage of the tetrabutyl titanate is 0.05 percent of the mass of the cane molasses water solution.

The dispersing agent is a mixture of polyanionic cellulose (PAC) and fatty alcohol-polyoxyethylene ether (AEO-9), and the mass ratio of the polyanionic cellulose to the fatty alcohol-polyoxyethylene ether is 1: 1.6.

The preparation method further comprises the following steps:

A. adding the cane molasses water solution with the formula amount into a reaction kettle, heating to 120 ℃, and performing reduced pressure dehydration, wherein the vacuum degree is controlled to be-0.095 Mpa;

B. after no obvious liquid is evaporated, closing the vacuum system, adding succinic acid, tridecanedioic acid, xylene and tetrabutyl titanate according to the formula amount, and continuously heating to the boiling point of xylene as a water-carrying agent to perform reflux water diversion reaction;

C. when the acid value of the system mixture is less than 10mgKOH/g, adding propionic acid with the formula amount for carrying out end-capping reaction, and then continuing carrying out reflux water-splitting reaction at the boiling point of xylene with water;

D. when the hydroxyl value of the system mixture is less than 10mgKOH/g, starting a vacuum system, keeping the vacuum degree at-0.095 Mpa, continuously heating to 145 ℃, and removing the xylene solvent, unreacted propionic acid and the like under reduced pressure;

E. stopping the vacuum system after no obvious substances are evaporated, cooling to room temperature, adding 1.2 times of the mass of the cane molasses water solution, washing with water for one time to remove residual propionic acid, catalyst and other impurities, removing the water phase in a layering manner to obtain a viscous liquid, and pumping the viscous liquid into an emulsifying kettle;

G. and then adding ethanol, water and a dispersing agent in a formula ratio into an emulsifying kettle, quickly stirring and emulsifying at room temperature for 2.5h, and discharging to obtain the aqueous adhesive after the emulsion stability meets the requirement.

Example 3

A preparation method of a low-cost aqueous adhesive comprises the following raw materials in parts by mass:

wherein the sugar cane molasses water solution is a sugar cane molasses water solution with solid content of 80%.

Wherein the catalyst is tetrabutyl titanate, and the dosage of the tetrabutyl titanate is 0.07 percent of the mass of the cane molasses water solution.

The dispersing agent is a mixture of polyanionic cellulose (PAC) and fatty alcohol-polyoxyethylene ether (AEO-9), and the mass ratio of the polyanionic cellulose to the fatty alcohol-polyoxyethylene ether is 1: 2.4.

The preparation method further comprises the following steps:

A. adding the cane molasses water solution with the formula amount into a reaction kettle, heating to 116 ℃, and carrying out reduced pressure dehydration, wherein the vacuum degree is controlled to be-0.097 Mpa;

B. after no obvious liquid is evaporated, closing the vacuum system, adding succinic acid, tridecanedioic acid, xylene and tetrabutyl titanate according to the formula amount, and continuously heating to the boiling point of xylene as a water-carrying agent to perform reflux water diversion reaction;

C. when the acid value of the system mixture is less than 10mgKOH/g, adding propionic acid with the formula amount for carrying out end-capping reaction, and then continuing carrying out reflux water-splitting reaction at the boiling point of xylene with water;

D. when the hydroxyl value of the system mixture is less than 10mgKOH/g, starting a vacuum system, keeping the vacuum degree at-0.097 Mpa, continuously heating to 148 ℃, and removing the xylene solvent and unreacted propionic acid under reduced pressure;

E. stopping the vacuum system after no obvious substances are evaporated, cooling to room temperature, adding 1 time of water solution of cane molasses by mass to wash once to remove residual propionic acid, catalyst and other impurities, removing the water phase in a layered manner to obtain viscous liquid, and pumping the viscous liquid into an emulsifying kettle;

G. and then adding ethanol, water and a dispersing agent in a formula ratio into an emulsifying kettle, quickly stirring and emulsifying at room temperature for 2.2h, and discharging to obtain the aqueous adhesive after the emulsion stability meets the requirement.

Example 4

A preparation method of a low-cost aqueous adhesive comprises the following raw materials in parts by mass:

wherein the sugar cane molasses water solution is a sugar cane molasses water solution with a solid content of 80 wt%.

Wherein the catalyst is tetrabutyl titanate, and the dosage of the tetrabutyl titanate is 0.08 percent of the mass of the cane molasses water solution.

The dispersing agent is a mixture of polyanionic cellulose (PAC) and fatty alcohol-polyoxyethylene ether (AEO-9), and the mass ratio of the polyanionic cellulose to the fatty alcohol-polyoxyethylene ether is 1: 2.2.

The preparation method further comprises the following steps:

A. adding the cane molasses water solution with the formula amount into a reaction kettle, heating to 113 ℃, and performing reduced pressure dehydration, wherein the vacuum degree is controlled to be-0.096 Mpa;

B. after no obvious liquid is evaporated, closing the vacuum system, adding succinic acid, tridecanedioic acid, xylene and tetrabutyl titanate according to the formula amount, and continuously heating to the boiling point of xylene as a water-carrying agent to perform reflux water diversion reaction;

C. when the acid value of the system mixture is less than 10mgKOH/g, adding propionic acid with the formula amount for carrying out end-capping reaction, and then continuing carrying out reflux water-splitting reaction at the boiling point of xylene with water;

D. when the hydroxyl value of the system mixture is less than 10mgKOH/g, starting a vacuum system, keeping the vacuum degree at-0.096 Mpa, continuously heating to 146 ℃, and removing the xylene solvent and unreacted propionic acid under reduced pressure;

E. stopping the vacuum system after no obvious substances are evaporated, cooling to room temperature, adding 1.1 times of sugar cane molasses water solution by mass, washing with water to remove residual propionic acid, catalyst and other impurities, removing the water phase in a layering manner to obtain a viscous liquid, and pumping into an emulsifying kettle;

G. and then adding ethanol, water and a dispersing agent in a formula ratio into an emulsifying kettle, quickly stirring and emulsifying at room temperature for 2.3h, and discharging to obtain the aqueous adhesive after the emulsion stability meets the requirement.

Comparative example 1

A commercially available ordinary paper-plastic composite adhesive product was used as the comparative example 1, EVA emulsion adhesive, available from Xin Yb adhesive products Co., Ltd, Dongguan.

Application of adhesive to paper-plastic composite material

The aqueous adhesives prepared in examples 1 to 4 were uniformly applied to the surface of printed paper with a coater, and the coating weight was 20g/m²And then putting the mixture into a 95 ℃ oven to be dried for 3min, uniformly sticking a BOPP film on the glued surface, standing at room temperature for 24h, and then sampling. Sampling size: the length is 200mm, and the width is 20 mm.

The test method comprises the following steps:

the adhesive bonding ability (peel strength) of the adhesive was performed according to GB/T2791-.

Emulsion stability test method: 100g of sample is put into a centrifuge tube, and then the sample is centrifuged and settled in a centrifuge at 3000r/min for 30min, so that the emulsion breaking phenomenon does not occur, and the mechanical stability of the emulsion can be considered to meet the application requirement.

The results of the performance tests are shown in table 1 below.

Table 1 results of performance testing of aqueous adhesives prepared in examples 1-4

As can be seen from comparison of examples 1-4 and comparative example 1 in Table 1, the invention prepares the product modified by sucrose molasses into the adhesive product for paper-plastic composite through mutual matching and synergistic effect of the components, has excellent emulsion stability and storage stability, moderate viscosity, better peel strength after drying and forming, equivalent performance to the adhesive of the commercially available EVA emulsion, can meet the requirements of paper-plastic composite materials, provides an idea for further deep processing of sucrose molasses byproducts, and greatly saves the production cost.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.