阅读说明：本技术 一种墙体无机板用胶黏剂及其制备方法 (Adhesive for inorganic board of wall and preparation method thereof ) 是由 雷响 于 2021-03-11 设计创作，主要内容包括：本发明公开了一种墙体无机板用胶黏剂,包括如下重量份的原料：聚酯二元醇15-20份、异佛尔酮二异氰酸酯10-12份、六亚甲基二异氰酸酯8-10份、催化剂0.5-1份、二羟甲基丙酸3-5份、KH5502-4份、改性淀粉乳液6-8份、三乙胺3-4份、蒸馏水2-3份、异佛尔酮二胺2-3份、增稠剂1-2份、消泡剂1-2份、润湿剂1-2份；本发明还公开了该墙体无机板用胶黏剂的制备方法。本发明中通过水性聚氨酯乳液和改性淀粉乳液复配,提高胶黏剂的力学性能,同时添加壳聚糖,增加胶黏剂的抗菌抑菌性能。(The invention discloses an adhesive for wall inorganic boards, which comprises the following raw materials in parts by weight: 15-20 parts of polyester diol, 10-12 parts of isophorone diisocyanate, 8-10 parts of hexamethylene diisocyanate, 0.5-1 part of catalyst, 3-5 parts of dimethylolpropionic acid, 2-4 parts of KH550, 6-8 parts of modified starch emulsion, 3-4 parts of triethylamine, 2-3 parts of distilled water, 2-3 parts of isophorone diamine, 1-2 parts of thickener, 1-2 parts of defoamer and 1-2 parts of wetting agent; the invention also discloses a preparation method of the adhesive for the wall inorganic board. According to the invention, the aqueous polyurethane emulsion and the modified starch emulsion are compounded, so that the mechanical property of the adhesive is improved, and the antibacterial and bacteriostatic properties of the adhesive are improved by adding chitosan.)

1. The adhesive for the inorganic board of the wall is characterized by comprising the following raw materials in parts by weight: 15-20 parts of polyester diol, 10-12 parts of isophorone diisocyanate, 8-10 parts of hexamethylene diisocyanate, 0.5-1 part of catalyst, 3-5 parts of dimethylolpropionic acid, 2-4 parts of KH550, 6-8 parts of modified starch emulsion, 3-4 parts of triethylamine, 2-3 parts of distilled water, 2-3 parts of isophorone diamine, 1-2 parts of thickener, 1-2 parts of defoamer and 1-2 parts of wetting agent;

the adhesive for the wall inorganic board is prepared by the following steps:

step A1, adding polyester diol into a flask, dehydrating for 1-2 hours in vacuum at the temperature of 100 ℃ and 105 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2-3 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1-1.5 hours, adding 5-10mL of acetone to adjust viscosity in the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3-4 hours, and finally decompressing acetone to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 250-280rpm for 5-10 minutes to prepare the adhesive for the inorganic board of the wall.

2. The adhesive for wall inorganic boards as claimed in claim 1, wherein: the catalyst described in step A1 was dibutyltin dilaurate.

3. The adhesive for wall inorganic boards as claimed in claim 1, wherein: the thickener in the step A2 is sodium alginate, the amount of the thickener is 1-1.2% of the mass of the polyurethane emulsion prepared in the step A1, the defoamer is emulsified silicone oil, the amount of the defoamer is 0.4-0.6% of the mass of the polyurethane emulsion prepared in the step A1, the wetting agent is sodium dodecyl benzene sulfonate, and the amount of the wetting agent is 0.5-0.6% of the mass of the polyurethane emulsion prepared in the step A1.

4. The adhesive for wall inorganic boards as claimed in claim 1, wherein: the modified starch emulsion is prepared by the following method:

step S1, adding corn starch and deionized water into a flask to prepare starch milk, adding epoxy chloropropane, controlling the temperature to be 70-80 ℃, stirring at the speed of 200-230rpm, reacting for 1.5-2 hours, and gelatinizing at 80-85 ℃ for 30-40 minutes to prepare cross-linked starch emulsion;

step S2, adding glacial acetic acid and chitosan into the flask, stirring at 30-35 ℃ until the chitosan is dissolved, adding the crosslinked starch emulsion prepared in the step S1, controlling the reaction temperature at 30-40 ℃, and reacting for 2-3.5 hours under the condition of the stirring speed of 250-280rpm to prepare the modified starch emulsion.

5. The adhesive for wall inorganic boards as claimed in claim 4, wherein: the dosage ratio of the corn starch and the deionized water in the step S1 is 50-60 g: 100-120mL, wherein the dosage of the epichlorohydrin is 0.1g of epichlorohydrin added to 100g of the starch milk.

6. The adhesive for wall inorganic boards as claimed in claim 4, wherein: the dosage ratio of the glacial acetic acid to the chitosan in the step S2 is 45-50g:1-1.2 g.

7. The preparation method of the adhesive for the inorganic board of the wall is characterized by comprising the following steps: the preparation method comprises the following preparation steps:

step A1, adding polyester diol into a flask, dehydrating for 1-2 hours in vacuum at the temperature of 100 ℃ and 105 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2-3 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1-1.5 hours, adding 5-10mL of acetone to adjust viscosity in the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3-4 hours, and finally decompressing acetone to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 250-280rpm for 5-10 minutes to prepare the adhesive for the inorganic board of the wall.

Technical Field

The invention belongs to the technical field of adhesives, and relates to an adhesive for a wall inorganic board and a preparation method thereof.

Background

The inorganic wall board has light weight, high fireproof and sound isolating performance and high construction efficiency, and is widely used in building industry. The adhesive is also called as an adhesive, the adhesive can be used for connecting the surfaces of homogeneous or heterogeneous objects together, the technology of connecting various materials or parts by using the adhesive is called as a bonding technology, the adhesives have various varieties and different compositions, and the adhesives are classified for convenient research and application and mainly classified according to the curing mode, the form, the water resistance and the like of the adhesive, wherein the curing mode comprises a solvent type, a hot melt type, a thermosetting type and a thermoplastic type; the form of the coating is solvent type, emulsion type, powder type, film type and solid type; the water resistance is high water resistance glue, medium water resistance glue, low water resistance glue and non-water resistance glue.

The waterborne polyurethane adhesive takes water as a solvent, has the advantages of adjustable hardness, no pollution, good compatibility, easy modification and the like, can be used for bonding various materials such as metal, nonmetal and the like, and has wider and wider application. However, the simple poly-amino acid emulsion can not meet the requirements of people in some properties, for example, the inorganic board and wall adhesive film has poor mechanical properties, and the wall becomes damp and mildewed, which leads to the great reduction of the adhesive properties, so that the development of an adhesive for wall inorganic boards is urgently needed to solve the problems.

Disclosure of Invention

The invention aims to provide an adhesive for wall inorganic boards and a preparation method thereof.

The purpose of the invention can be realized by the following technical scheme:

the adhesive for the inorganic board of the wall comprises the following raw materials in parts by weight:

15-20 parts of polyester diol, 10-12 parts of isophorone diisocyanate, 8-10 parts of hexamethylene diisocyanate, 0.5-1 part of catalyst, 3-5 parts of dimethylolpropionic acid, 2-4 parts of KH550, 6-8 parts of modified starch emulsion, 3-4 parts of triethylamine, 2-3 parts of distilled water, 2-3 parts of isophorone diamine, 1-2 parts of thickener, 1-2 parts of defoamer and 1-2 parts of wetting agent;

the adhesive for the wall inorganic board is prepared by the following steps:

step A1, adding polyester diol into a flask, dehydrating for 1-2 hours in vacuum at the temperature of 100 ℃ and 105 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2-3 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1-1.5 hours, adding 5-10mL of acetone to adjust viscosity in the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3-4 hours, and finally decompressing acetone to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 250-280rpm for 5-10 minutes to prepare the adhesive for the inorganic board of the wall.

Further, the catalyst described in step A1 was dibutyltin dilaurate.

Further, the thickener in the step a2 is sodium alginate, the amount of the thickener is 1 to 1.2% of the mass of the polyurethane emulsion prepared in the step a1, the defoamer is emulsified silicone oil, the amount of the defoamer is 0.4 to 0.6% of the mass of the polyurethane emulsion prepared in the step a1, the wetting agent is sodium dodecyl benzene sulfonate, and the amount of the wetting agent is 0.5 to 0.6% of the mass of the polyurethane emulsion prepared in the step a 1.

Further, the modified starch emulsion is prepared by the following method:

step S1, adding corn starch and deionized water into a flask to prepare starch milk, adding epoxy chloropropane, controlling the temperature to be 70-80 ℃, stirring at the speed of 200-230rpm, reacting for 1.5-2 hours, and gelatinizing at 80-85 ℃ for 30-40 minutes to prepare cross-linked starch emulsion;

step S2, adding glacial acetic acid and chitosan into the flask, stirring at 30-35 ℃ until the chitosan is dissolved, adding the crosslinked starch emulsion prepared in the step S1, controlling the reaction temperature at 30-40 ℃, and reacting for 2-3.5 hours under the condition of the stirring speed of 250-280rpm to prepare the modified starch emulsion.

Further, the using amount ratio of the corn starch and the deionized water in the step S1 is 50-60 g: 100-120mL, wherein the dosage of the epichlorohydrin is 0.1g of epichlorohydrin added to 100g of the starch milk.

Further, the dosage ratio of the glacial acetic acid and the chitosan in the step S2 is 45-50g:1-1.2 g.

The preparation method of the adhesive for the inorganic board of the wall comprises the following preparation steps:

step A1, adding polyester diol into a flask, dehydrating for 1-2 hours in vacuum at the temperature of 100 ℃ and 105 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2-3 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1-1.5 hours, adding 5-10mL of acetone to adjust viscosity in the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3-4 hours, and finally decompressing acetone to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 250-280rpm for 5-10 minutes to prepare the adhesive for the inorganic board of the wall.

The invention has the beneficial effects that: the invention aims to provide an adhesive for wall inorganic boards and a preparation method thereof, the mechanical property of the adhesive is improved by compounding an aqueous polyurethane emulsion and a modified starch emulsion, chitosan is added to improve the antibacterial and bacteriostatic properties of the adhesive, the aqueous polyurethane adhesive takes water as a solvent, has the advantages of adjustable hardness, no pollution, good compatibility, easy modification and the like, a silane coupling agent KH550 is added, the KH550 contains active terminal amino groups and is introduced into a polyurethane chain to form a net structure, the crosslinking density of an adhesive film can be improved, the heat resistance, the water resistance and the mechanical property of the adhesive are improved by silicon oxygen bonds, the modified starch emulsion is added, active chlorine groups and epoxy groups on epoxy chloropropane and hydroxyl groups on a starch molecular chain are subjected to crosslinking reaction to generate a substance with a net structure between the starch and the crosslinking agent epoxy chloropropane, starch granules in the cross-linked starch are in linkage with different degrees by chemical bonds, the strength of the chemical bonds is higher than that of hydrogen bonds, the strength of the structure of the starch granules is enhanced, the granules are inhibited from expanding, cracking and viscosity reduction, the shearing resistance is also greatly improved, and the acid and alkali resistance, the gluing strength and the heat resistance are further improved.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The adhesive for the inorganic board of the wall comprises the following raw materials in parts by weight:

15 parts of polyester diol, 10 parts of isophorone diisocyanate, 8 parts of hexamethylene diisocyanate, 0.5 part of catalyst, 3 parts of dimethylolpropionic acid, 3 parts of KH5502 parts of modified starch emulsion, 3 parts of triethylamine, 2 parts of distilled water, 2 parts of isophorone diamine, 1 part of thickening agent, 1 part of defoaming agent and 1 part of wetting agent;

the adhesive for the wall inorganic board is prepared by the following steps:

step A1, adding polyester diol into a flask, dehydrating for 1 hour at 100 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1 hour, adding 5mL of acetone to adjust viscosity during the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3 hours, and finally distilling off acetone under reduced pressure to obtain a polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 250rpm for 5 minutes to prepare the adhesive for the inorganic board of the wall.

Wherein the catalyst in the step A1 is dibutyltin dilaurate.

Wherein the thickener in the step A2 is sodium alginate, the dosage of the thickener is 1% of the mass of the polyurethane emulsion prepared in the step A1, the defoamer is emulsified silicone oil, the dosage of the defoamer is 0.4% of the mass of the polyurethane emulsion prepared in the step A1, the wetting agent is sodium dodecyl benzene sulfonate, and the dosage of the wetting agent is 0.5% of the mass of the polyurethane emulsion prepared in the step A1.

The modified starch emulsion is prepared by the following method:

step S1, adding corn starch and deionized water into a flask to prepare starch milk, adding epoxy chloropropane, controlling the temperature to be 75 ℃, stirring at the speed of 200rpm, reacting for 1.5 hours, and gelatinizing at 80 ℃ for 30 minutes to prepare crosslinked starch emulsion;

and step S2, adding glacial acetic acid and chitosan into the flask, stirring at 30 ℃ until the chitosan is dissolved, adding the crosslinked starch emulsion prepared in the step S1, controlling the reaction temperature to be 30 ℃, and reacting for 2 hours at the stirring speed of 250rpm to prepare the modified starch emulsion.

Wherein the dosage ratio of the corn starch to the deionized water in the step S1 is 50g: 100mL, wherein the dosage of the epichlorohydrin is 0.1g of the epichlorohydrin added to every 100g of the starch milk.

Wherein the dosage ratio of the glacial acetic acid and the chitosan in the step S2 is 45g to 1 g.

The preparation method of the adhesive for the inorganic board of the wall comprises the following preparation steps:

step A1, adding polyester diol into a flask, dehydrating for 1 hour at 100 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1 hour, adding 5mL of acetone to adjust viscosity during the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3 hours, and finally distilling off acetone under reduced pressure to obtain a polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 250rpm for 5 minutes to prepare the adhesive for the inorganic board of the wall.

Example 2

The adhesive for the inorganic board of the wall comprises the following raw materials in parts by weight:

18 parts of polyester diol, 11 parts of isophorone diisocyanate, 9 parts of hexamethylene diisocyanate, 0.7 part of catalyst, 4 parts of dimethylolpropionic acid, 3 parts of KH5503 parts of modified starch emulsion, 3.5 parts of triethylamine, 2.5 parts of distilled water, 2.5 parts of isophorone diamine, 1.5 parts of thickener, 1.5 parts of defoamer and 1.5 parts of wetting agent;

the adhesive for the wall inorganic board is prepared by the following steps:

step A1, adding polyester diol into a flask, dehydrating for 1.5 hours in vacuum at 102 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2.5 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1.5 hours, adding 7mL of acetone to adjust viscosity in the reaction process, cooling to 50 ℃ to obtain polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3.5 hours, and finally, distilling off acetone under reduced pressure to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 260rpm for 7 minutes to prepare the adhesive for the inorganic board of the wall.

Wherein the catalyst in the step A1 is dibutyltin dilaurate.

Wherein the thickener in the step A2 is sodium alginate, the dosage of the thickener is 1.1% of the mass of the polyurethane emulsion prepared in the step A1, the defoamer is emulsified silicone oil, the dosage of the defoamer is 0.5% of the mass of the polyurethane emulsion prepared in the step A1, the wetting agent is sodium dodecyl benzene sulfonate, and the dosage of the wetting agent is 0.55% of the mass of the polyurethane emulsion prepared in the step A1.

The modified starch emulsion is prepared by the following method:

step S1, adding corn starch and deionized water into a flask to prepare starch milk, adding epoxy chloropropane, controlling the temperature to be 75 ℃, stirring at the speed of 200rpm, reacting for 2 hours, and gelatinizing at 80 ℃ for 35 minutes to prepare crosslinked starch emulsion;

and step S2, adding glacial acetic acid and chitosan into the flask, stirring at 33 ℃ until the chitosan is dissolved, adding the crosslinked starch emulsion prepared in the step S1, controlling the reaction temperature to be 35 ℃, and reacting for 3 hours at the stirring speed of 270rpm to prepare the modified starch emulsion.

Wherein the dosage ratio of the corn starch to the deionized water in the step S1 is 55 g: 110mL, and the dosage of the epichlorohydrin is 0.1g of epichlorohydrin added in each 100g of starch milk.

Wherein the dosage ratio of the glacial acetic acid and the chitosan in the step S2 is 45g to 1 g.

The preparation method of the adhesive for the inorganic board of the wall comprises the following preparation steps:

step A1, adding polyester diol into a flask, dehydrating for 1.5 hours in vacuum at 102 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 2.5 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1.5 hours, adding 7mL of acetone to adjust viscosity in the reaction process, cooling to 50 ℃ to obtain polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 3.5 hours, and finally, distilling off acetone under reduced pressure to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 260rpm for 7 minutes to prepare the adhesive for the inorganic board of the wall.

Example 3

The adhesive for the inorganic board of the wall comprises the following raw materials in parts by weight:

20 parts of polyester diol, 12 parts of isophorone diisocyanate, 10 parts of hexamethylene diisocyanate, 1 part of catalyst, 5 parts of dimethylolpropionic acid, 4 parts of KH5504 parts, 8 parts of modified starch emulsion, 4 parts of triethylamine, 3 parts of distilled water, 3 parts of isophorone diamine, 2 parts of thickening agent, 2 parts of defoaming agent and 2 parts of wetting agent;

the adhesive for the wall inorganic board is prepared by the following steps:

step A1, adding polyester diol into a flask, dehydrating for 2 hours in vacuum at 105 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 3 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1.5 hours, adding 10mL of acetone to adjust viscosity during the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 4 hours, and finally, evaporating acetone under reduced pressure to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 280rpm for 10 minutes to prepare the adhesive for the inorganic board of the wall.

Wherein the catalyst in the step A1 is dibutyltin dilaurate.

Wherein the thickener in the step A2 is sodium alginate, the dosage of the thickener is 1.2% of the mass of the polyurethane emulsion prepared in the step A1, the defoamer is emulsified silicone oil, the dosage of the defoamer is 0.6% of the mass of the polyurethane emulsion prepared in the step A1, the wetting agent is sodium dodecyl benzene sulfonate, and the dosage of the wetting agent is 0.6% of the mass of the polyurethane emulsion prepared in the step A1.

The modified starch emulsion is prepared by the following method:

step S1, adding corn starch and deionized water into a flask to prepare starch milk, adding epoxy chloropropane, controlling the temperature to be 80 ℃, stirring at the speed of 230rpm, reacting for 2 hours, and gelatinizing at 85 ℃ for 40 minutes to prepare crosslinked starch emulsion;

and step S2, adding glacial acetic acid and chitosan into the flask, stirring at 35 ℃ until the chitosan is dissolved, adding the crosslinked starch emulsion prepared in the step S1, and reacting for 3.5 hours under the conditions that the reaction temperature is controlled at 40 ℃ and the stirring speed is 280rpm to prepare the modified starch emulsion.

Wherein the dosage ratio of the corn starch to the deionized water in the step S1 is 60 g: 120mL, and the dosage of the epichlorohydrin is 0.1g of epichlorohydrin added to every 100g of the starch milk.

Wherein the dosage ratio of the glacial acetic acid and the chitosan in the step S2 is 50g to 1 g.

The preparation method of the adhesive for the inorganic board of the wall comprises the following preparation steps:

step A1, adding polyester diol into a flask, dehydrating for 2 hours in vacuum at 105 ℃, then cooling to 80 ℃, adding isophorone diisocyanate and hexamethylene diisocyanate, dropwise adding a catalyst, reacting for 3 hours, cooling to 75 ℃, adding dimethylolpropionic acid and modified starch emulsion, continuing to react for 3.5 hours, cooling to 50 ℃, adding KH550, continuing to react for 1.5 hours, adding 10mL of acetone to adjust viscosity during the reaction process, cooling to 50 ℃ to obtain a polyurethane prepolymer, adding triethylamine, distilled water and isophorone diamine, performing chain extension reaction for 4 hours, and finally, evaporating acetone under reduced pressure to obtain polyurethane emulsion;

and A2, adding a thickening agent, a defoaming agent and a wetting agent into the polyurethane emulsion prepared in the step A1, and stirring at the rotating speed of 280rpm for 10 minutes to prepare the adhesive for the inorganic board of the wall.

Comparative example 1

The adhesive is commercially available for wall inorganic boards.

Comparative example 2

Comparative example 2 preparation method of adhesive for wall inorganic board referring to example 1, except that modified starch emulsion was not added.

The adhesives for wall inorganic boards obtained in examples 1 to 3 and comparative examples 1 and 2 were subjected to the following performance tests:

the adhesives for wall inorganic boards obtained in examples 1-3 and comparative examples 1 and 2 were tested for adhesive strength and antibacterial performance (staphylococcus aureus, escherichia coli), specifically, (1) adhesive strength, according to the GB/T14074.10-93 standard; (2) antibacterial performance according to the evaluation method of antibacterial effect of antibacterial article specified in Japanese Industrial Standard JIS Z2801, test data are shown in Table 1

As can be seen from Table 1, the adhesives for wall inorganic boards prepared in examples 1-3 have better bonding strength, and the antibacterial rate of Staphylococcus aureus and the antibacterial rate of Escherichia coli are obviously superior to those of the comparative examples, and have excellent antibacterial performance, so that the adhesives have wide application prospects.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.