CN113429909A

CN113429909A - Alkali-gelatinized wet glue and preparation method and application thereof

Info

Publication number: CN113429909A
Application number: CN202110816897.5A
Authority: CN
Inventors: 詹深圳
Original assignee: Jiangmen Lanyu Building Adhesive Industrial Co ltd
Current assignee: Jiangmen Lanyu Building Adhesive Industrial Co ltd
Priority date: 2020-11-17
Filing date: 2021-07-20
Publication date: 2021-09-24
Anticipated expiration: 2041-07-20
Also published as: CN113429909B; CN112457800A

Abstract

The embodiment of the invention relates to alkali-gelatinized wet glue and a preparation method and application thereof, wherein the alkali-gelatinized wet glue is prepared from the following raw material components in parts by weight: 7-25 parts of acetylated starch, 4-16 parts of hydroxypropyl distarch phosphate, 1-10 parts of water-soluble inorganic salt, 0.2-5 parts of alkaline pasting agent, 0.2-5 parts of acid neutralizing agent, 0.4-10 parts of auxiliary agent and 60-80 parts of water. The alkali-gelatinized wet glue prepared by the invention is superior to wet glue prepared by a hot gelatinization process in the aspects of corrosion and mildew resistance, adhesion performance, glue opening performance, storage stability, freezing resistance and the like.

Description

Alkali-gelatinized wet glue and preparation method and application thereof

Technical Field

The invention belongs to the field of adhesives, relates to a novel wallpaper/wall cloth wet glue, and particularly relates to a novel alkali-gelatinized wallpaper/wall cloth wet glue as well as a preparation method and application thereof.

Background

In recent years, wallpaper wall cloth becomes a preferred decoration material for beautifying indoor environment, and starch adhesive is widely applied to the market as adhesive for adhering the wallpaper wall cloth.

The wallpaper wall cloth wet glue can be divided into two types of hot-gelatinized wet glue and alkali-gelatinized wet glue according to the preparation method of the process, and the two preparation processes have the advantages but have some disadvantages respectively. And (3) hot gelatinization, namely, direct heating and water boiling of the starch to obtain the adhesive. The wet glue prepared by the hot gelatinization process is simple and convenient to operate, easy to operate by workers and low in preparation cost, and is prepared by directly mixing starch and water uniformly, adding an auxiliary agent, stirring, heating and gelatinizing; however, the wet glue after hot gelatinization has poor glue-opening performance, can not be used by adding water, or is difficult to open after adding water, or the glue solution after opening is rough and has insufficient smoothness, the bonding performance is general, the wet glue of starch with high solid content of more than 30 percent can not be prepared by the hot gelatinization process, particularly, the wet glue is easy to be warped when being used for bonding certain wall cloths with relative thickness, and the wet glue is easy to generate mildewed water, so that the requirements on the antiseptic mildew inhibitor are high.

The alkali gelatinization process is a process for gelatinizing starch by using an alkali gelatinization agent at normal temperature, and the existing wallpaper wall cloth wet glue prepared by using the alkali gelatinization process has higher viscosity compared with a hot gelatinization starch adhesive, but has high preparation operation difficulty, more working procedures and more attention points and tracking points, so that the operation requirement on workers is higher, and the preparation cost is also higher. Therefore, there is a need to develop a wet adhesive for wallpaper and wall cloth with high adhesion and easy construction and operation for workers.

Disclosure of Invention

In view of the above, the embodiment of the invention provides the alkali-gelatinized wet glue suitable for adhering the wallpaper wall cloth, and the preparation method and the application thereof, the wallpaper wall cloth glue with high viscosity and high solid content is prepared by the preparation method of the embodiment of the invention, the thick wall cloth can be adhered, the glue is easy to open, and the construction operation of workers is easy; the prepared wet glue is superior to the wet glue prepared by the hot pasting process in the aspects of corrosion resistance, mildew resistance, adhesive property, glue opening property, storage stability, freezing resistance and the like.

The technical scheme adopted by the invention is as follows: the alkali-gelatinized wet glue is prepared from the following raw material components in parts by weight:

7-25 parts of acetylated starch,

4-16 parts of hydroxypropyl distarch phosphate,

1-10 parts of water-soluble inorganic salt,

0.2 to 5 portions of alkaline pasting agent,

0.2 to 5 portions of acid neutralizer,

0.4 to 10 portions of auxiliary agent,

60-80 parts of water.

In some embodiments of the present invention, the alkali-gelatinized wet glue is prepared from the following raw material components in parts by weight: 10-20 parts of acetylated starch, 5-10 parts of hydroxypropyl distarch phosphate, 4-8 parts of water-soluble inorganic salt, 0.5-2 parts of alkaline pasting agent, 0.5-2 parts of acid neutralizing agent, 0.9-4 parts of auxiliary agent and 63-75 parts of water.

According to the embodiment of the present invention, the acetylated starch refers to a modified starch obtained by acetylating a starch known in the art by a starch acetylation modification method known to those skilled in the art, for example, a modified starch obtained by acetylating one or more of tapioca starch, waxy corn starch, wheat starch and potato starch by using acetic anhydride and the like as an acetylating agent. According to an embodiment of the invention, the acetylated starch comprises one or more of acetylated tapioca starch, acetylated waxy maize starch, acetylated wheat starch and acetylated potato starch. The use of the acetylated starch can obviously improve the hardness, solid content, bonding force and frost resistance of the prepared wet glue alkali-gelatinized wet glue.

According to the embodiment of the invention, the hydroxypropyl distarch phosphate refers to modified starch obtained by modifying starch known in the art by a starch hydroxypropyl phosphate modification method known by a person skilled in the art, or is referred to as hydroxypropyl phosphate modified starch; starch materials which may be modified with hydroxypropyl phosphate include tapioca starch, waxy corn starch, wheat starch, and potato starch. According to the embodiment of the invention, the hydroxypropyl distarch phosphate comprises one or more of hydroxypropyl phosphate modified tapioca starch, hydroxypropyl phosphate modified corn starch, hydroxypropyl phosphate modified wheat starch and hydroxypropyl phosphate modified potato starch. The hydroxypropyl distarch phosphate can greatly increase the stability of the prepared wet glue at different temperatures, and can directly influence the viscosity of the wet glue and increase the glue opening amount of the wet glue.

According to the embodiment of the present invention, one or more of chloride, nitrate, sodium, sulfate and phosphate may be used as the water-soluble inorganic salt. In some embodiments of the invention, where a water-soluble inorganic salt is used, an aqueous solution of the water-soluble inorganic salt is added. In some embodiments, a 15% -40% aqueous solution of a water-soluble inorganic salt is added.

According to the embodiment of the present invention, the alkaline pasting agent may use an inorganic base or an alkaline inorganic salt known to those skilled in the art, for example, the alkaline pasting agent includes one or more of potassium hydroxide, sodium hydroxide, magnesium hydroxide, calcium hydroxide, sodium phosphate and sodium carbonate. In some embodiments of the invention, where a basic pasting agent is used, an aqueous solution of the basic pasting agent is added. In some embodiments, a 20% -40% aqueous solution of an alkaline pasting agent is added.

According to the embodiment of the present invention, the acid neutralizer may use an inorganic acid or an organic acid known to those skilled in the art, for example, the acid neutralizer includes one or more of nitric acid, hydrochloric acid, oxalic acid, and phosphoric acid. In some embodiments of the present invention, the acid neutralizer is used at a concentration of 5% to 20%.

According to the embodiment of the invention, the auxiliary agent can comprise one or more of a whitening agent, a humectant, an antifreeze agent and a preservative and mildew inhibitor. In some embodiments, the auxiliary agent comprises 0.1-2 parts of whitening agent, 0.1-1.5 parts of humectant, 0.1-1.5 parts of antifreeze agent and 0.1-3 parts of antiseptic and mildew-proof agent. In some embodiments, the auxiliary agent comprises 0.2-1 part of whitening agent, 0.1-0.5 part of humectant, 0.1-0.3 part of antifreeze agent and 0.5-1.5 parts of antiseptic and mildew inhibitor.

In some embodiments, the whitening agent may be one or more agents conventional in the art, including but not limited to EVA emulsion, titanium dioxide, and talc.

In some embodiments, the humectant may be selected from humectants conventional in the art, including, but not limited to, one or more of glycerin, carboxymethyl modified starch, and pentanediol.

In some embodiments, the antifreeze agent may be selected from antifreeze agents conventional in the art, including but not limited to one or more of propylene glycol, glycerol, and ethylene glycol.

In some embodiments, the preservative and mildew inhibitor may be one or more of those conventional in the art, including but not limited to sodium diacetate, benzoic acid and its sodium salt, quaternary ammonium organosilicone salt, and cason.

The embodiment of the invention also provides a preparation method of the alkali gelatinized wet glue, which comprises the following steps:

adding acetylated starch into water, adding water-soluble inorganic salt, and stirring to obtain a dispersed material;

adding part of the alkaline pasting agent to the dispersed material, and stirring to obtain a pre-pasted dispersed material;

adding hydroxypropyl distarch phosphate into the pre-gelatinized dispersed material, adding the residual alkaline gelatinizing agent, and stirring to obtain a gelatinized material;

adding an acid neutralizer into the gelatinized material, adjusting the pH, adding an auxiliary agent, and stirring to obtain the alkali gelatinized wet glue.

In order to enable the added raw material components to be more easily dispersed or dissolved in the material system, the raw material components to be added may be dispersed or dissolved with a part of water in advance. In some embodiments, the water-soluble inorganic salt is formulated with a portion of the water as an inorganic salt solution. In some embodiments, the basic pasting agent is formulated as a basic solution with a portion of the water. In some embodiments, the acid neutralizer is formulated as an acidic solution with a portion of the water.

The invention also provides application of the alkali-gelatinized wet glue as a wallpaper/wall cloth adhesive.

The invention has the beneficial effects that:

the alkali-gelatinized wet adhesive prepared by the alkali-gelatinized process technology has high adhesive force, can be used for bonding thick wallpaper/wall cloth, is not easy to warp edges of the bonded wallpaper/wall cloth, and can be used for preparing the wall cloth adhesive with high viscosity and high solid content; the glue is easy to open, water can be added according to the proportion of 1:1, even more than 1:1.5, the viscosity can reach more than 80000mPa.s after glue opening, and the construction operation of workers is easy.

In the process of alkali gelatinization, a material system is in a strong alkaline environment, the sterilization is more thorough, and the prepared wet glue has better antiseptic and mildew-proof performance, bonding performance, glue opening performance, storage stability, freezing resistance and the like than the wet glue prepared by a hot gelatinization process. The alkali gelatinized wet glue is easy to unfreeze and restore to the original state after being frozen and thawed at the temperature of-18 ℃. The quality guarantee period of the alkali gelatinized wet glue is at least one year, and the performance is still good even after three years under the condition of not unpacking.

Therefore, the adhesive capacity of the alkali gelatinized wallpaper/wall cloth wet adhesive is superior to that of the conventional liquid wallpaper wet adhesive, and the adhesive force and the glue opening easiness after freezing are superior to those of the hot gelatinized wallpaper wet adhesive on the market.

Drawings

Figure 1 shows the packaged finished product of the alkali-gelatinized wet glue obtained in example 2.

Figure 2 shows the alkali-gelatinized wet glue of example 2 after the glue is broken by 1:1 addition of water.

FIG. 3 shows the alkali-gelatinized wet gel of example 3 after the gel is broken by 1:1 addition of water.

Figure 4 shows the alkali-gelatinized wet glue of example 4 after the glue is broken by 1:1 addition of water.

FIG. 5 shows the alkali-gelatinized wet gel of example 2 after the gel has been opened, as tested using an NDJ-1 rotational viscometer.

Figure 6 shows the results of the alkali-gelatinized wet glue of example 2 after testing the open glue using a viscometer.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to the following examples.

In the existing common hot gelatinization process technology, modified starch and water are directly and uniformly mixed, then an auxiliary agent is added, and the mixture is stirred, heated and directly cooked for gelatinization to prepare the starch paste; however, the wet glue prepared by hot gelatinization has poor glue opening property, cannot be used by adding water, cannot form uniform phase after adding water, or has insufficient smoothness after glue opening, has general adhesive property, cannot prepare the starch wet glue with high solid content of more than 30 percent, is easy to warp edges particularly when adhering certain wall cloths with relative thickness, is easy to generate mildewed water, has short shelf life, is generally less than half a year, and has high requirements on the antiseptic and mildew-proof agent. Although the existing wallpaper wall cloth wet glue prepared by using an alkali gelatinization process has higher viscosity than a hot gelatinization starch adhesive, the preparation operation difficulty is high, the operation requirement on workers is higher during use, the number of working procedures is more, the number of cautions and tracking points is more, and the manufacturing cost is also higher.

In view of the above, according to a first aspect of the present invention, embodiments of the present invention relate to an alkali-gelatinized wet glue which has high bonding strength, good glue-opening performance, high solid content, easy storage, and freeze resistance. The invention relates to alkali-gelatinized wallpaper wet glue, in particular to wallpaper wet glue prepared by an alkali-gelatinized process. The novel wallpaper wall cloth wet glue can be prepared by using a brand new alkali pasting process technology and using an alkali pasting agent to paste modified starch under certain conditions.

According to the embodiment of the invention, the alkali-gelatinized wet glue is prepared from the following raw material components in parts by weight: 7-25 parts of acetylated starch, 4-16 parts of hydroxypropyl distarch phosphate, 1-10 parts of water-soluble inorganic salt, 0.2-5 parts of alkaline pasting agent, 0.2-5 parts of acid neutralizing agent, 0.4-10 parts of auxiliary agent and 60-80 parts of water.

In some embodiments, the alkali-gelatinized wet glue is prepared from the following raw material components in parts by weight: 10-20 parts of acetylated starch, 5-10 parts of hydroxypropyl distarch phosphate, 4-8 parts of water-soluble inorganic salt, 0.5-2 parts of alkaline pasting agent, 0.5-2 parts of acid neutralizing agent, 0.9-4 parts of auxiliary agent and 63-75 parts of water.

For example, the acetylated starch may be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 parts by weight;

the hydroxypropyl distarch phosphate can be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts;

the water-soluble inorganic salt can be 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6.0 parts, 6.5 parts, 7.0 parts, 7.5 parts or 8 parts;

the basic pasting agent may be 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.85 parts, 0.9 parts, 0.95 parts, 1.0 parts, 1.1 parts, 1.2 parts, 1.4 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, or 2.0 parts;

the acid neutralizer may be 0.5 parts, 0.55 parts, 0.6 parts, 0.65 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts, 1.2 parts, 1.4 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, or 2.0 parts;

the water may be 63 parts, 64 parts, 65 parts, 66 parts, 67 parts, 68 parts, 69 parts, 70 parts, 71 parts, 72 parts, 73 parts, 73.5 parts, 74 parts, 74.2 parts, 74.5 parts, 74.7 parts, or 75 parts. In some embodiments, the water may be deionized and/or distilled water.

In some embodiments, the adjuvant may include one or more of a whitening agent, a moisturizing agent, an anti-freezing agent, and a preservative and anti-mold agent. In some embodiments, the whitener, moisturizer, antifreeze, and preservative and mildewcide have a purity of 95 to 99%. In some embodiments, the auxiliary agent comprises 0.1-2 parts of whitening agent, 0.1-1.5 parts of humectant, 0.1-1.5 parts of antifreeze agent and 0.1-3 parts of antiseptic and mildew-proof agent. In some embodiments, the auxiliary agent comprises 0.2-1 part of whitening agent, 0.1-0.5 part of humectant, 0.1-0.3 part of antifreeze agent and 0.5-1.5 parts of antiseptic and mildew inhibitor.

For example, the whitening agent may be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.7 parts, 0.75 parts, 0.8 parts, 0.85 parts, 0.9 parts, 0.95 parts, or 1.0 parts by weight; the humectant can be 0.1 part, 0.15 part, 0.2 part, 0.25 part, 0.3 part, 0.35 part, 0.4 part, 0.45 part or 0.5 part; the antifreeze can be 0.1 part, 0.12 part, 0.15 part, 0.2 part, 0.25 part, 0.26 part, 0.28 part or 0.3 part; the mildew-resistant preservative may be 0.5 parts, 0.55 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 0.95 parts, 1.0 parts, 1.05 parts, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts or 1.5 parts.

For example, in one embodiment, the alkali-gelatinized wet gum is prepared from the following raw material components in parts by weight: 10 parts of acetylated starch, 5 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.5 parts of an alkaline pasting agent, 1.6 parts of an acid neutralizing agent, 0.2 part of an antifreeze agent, 0.7 part of an antiseptic and mildew-proof agent and 76 parts of water.

For example, in another embodiment, the alkali-gelatinized wet gum is prepared from the following raw material components in parts by weight: 16 parts of acetylated starch, 8 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.2 parts of alkaline pasting agent, 1.5 parts of acidic neutralizing agent, 0.4 part of whitening agent, 0.5 part of humectant, 0.2 part of antifreeze agent, 0.4 part of antiseptic and mildew-proof agent and 66.8 parts of water.

In some embodiments, the acetylated starch comprises one or more of an acetylated tapioca starch, an acetylated waxy corn starch, an acetylated wheat starch, and an acetylated potato starch. In some embodiments, the acetylated starch has a purity of 99% or greater. The inventor finds that in the process of preparing the alkali gelatinized wet glue, the acetylated starch can obviously improve the hardness of the alkali gelatinized wet glue, so that colloidal substances can be harder than common wet glue when being kneaded, the solid content of the prepared wet glue is improved, and the bonding force is indirectly improved; if other modified starch (such as oxidized starch) is used, the prepared wet glue has no frost resistance although the viscosity is higher than that of the hot gelatinized wet glue, and the viscosity is very thin, so that the preparation of the wet glue with high viscosity and high glue failure is not facilitated.

In some embodiments, the hydroxypropyl distarch phosphate comprises one or more of hydroxypropyl phosphate modified tapioca starch, hydroxypropyl phosphate modified corn starch, hydroxypropyl phosphate modified wheat starch, and hydroxypropyl phosphate modified potato starch. In some embodiments, the hydroxypropyl distarch phosphate has a purity of 99% or greater. The inventor of the application finds that in the process of preparing the alkali gelatinized wet glue, the stability of heat resistance, freezing resistance, normal temperature and the like of the prepared wet glue can be greatly improved by using the hydroxypropyl distarch phosphate; secondly, the viscosity of the wet glue can be directly influenced, the glue opening amount of the wet glue is increased, and the viscosity of the prepared wet glue is increased along with the increase of the adding amount of the wet glue.

In earlier researches, the inventor of the application finds that the viscosity of the alkali gelatinized wet glue prepared by selecting other types of modified starch, such as carboxymethyl starch, is slightly larger, but the glue is relatively harder to be opened, the water amount for opening the glue is larger, and even if the glue is too thin after being opened, the viscous force is poor, and the thick wall cloth cannot be adhered. Wherein, the viscosity of the wet glue prepared by using the oxidized starch is too low, the performance of the wet glue matched with the acetylated starch or the hydroxypropyl distarch phosphate is unstable, the viscosity is easy to further thin, the hand feeling of the prepared wet glue is soft, and the glue opening performance is poor; the wet glue prepared by using the cross-linked modified starch has poor viscosity, and the film layer is brittle, so that the wet glue cannot be applied to wet glue of wallpaper and wall cloth. Therefore, the acetylated starch is matched with the hydroxypropyl distarch phosphate to generate perfect combination of hardness and glue opening amount in a proper dosage range, the glue opening amount is large and easy, the hardness hand feeling of wet glue can be ensured, and the optimal balance point of solid content, viscosity, stability and glue opening performance can be ensured by combining the acetylated starch and the hydroxypropyl distarch phosphate.

In some embodiments, the water-soluble inorganic salt comprises one or more of chloride, nitrate, sodium, sulfate, and phosphate. From the aspect of cost effectiveness, water-soluble inorganic salts that are not 100% pure may be selected, preferably of commercial purity. Preferably, the purity of the water-soluble inorganic salt is more than 95%; further preferably, the water-soluble inorganic salt has a purity of 95 to 99%. The inventor finds that in the process of preparing the alkali gelatinized wet glue, the water solubility of the starch can be increased by using the water-soluble inorganic salt, so that the starch is easier to split, and meanwhile, the anti-freezing performance of the alkali gelatinized wet glue is improved.

In some embodiments, the water-soluble inorganic salt is used in the form of an inorganic salt solution, i.e., the water-soluble inorganic salt is formulated with a portion of water as an inorganic salt solution, and the concentration of the inorganic salt solution is 15-40%, specifically 20-40%, further preferably 25-35%, specifically 25%, 27%, 28%, 30%, 31%, 33%, or 35%. Unless otherwise specified above or below, the concentration of the solution prepared herein refers to the mass percent concentration of the solvent.

In some embodiments, the alkaline pasting agent comprises one or more of potassium hydroxide, sodium hydroxide, magnesium hydroxide, calcium hydroxide, sodium phosphate, and sodium carbonate. Alkaline pasting agents of other than 100% purity may be used, preferably of technical purity. Preferably, the purity of the alkaline pasting agent is more than 95%; further preferably, the basic pasting agent has a purity of 95 to 99%. Unless otherwise specified above or below, the purity of the starting components used herein may be of technical grade.

In some embodiments, the basic pasting agent is used in the form of a basic pasting agent solution, i.e., the basic pasting agent is formulated with a portion of water to form a basic solution, and the concentration of the basic pasting agent solution is 20-40%, and specifically, the concentration may be 21%, 22%, 23%, 24%, 25%, 26%, 27%, 29%, 30%, 31%, 32%, 34%, 36%, 38%, 40%, preferably 25-30%, and more preferably 30%.

In some embodiments, the acid neutralizer comprises one or more of nitric acid, hydrochloric acid, oxalic acid, and phosphoric acid. In some embodiments, the acid neutralizer is diluted to a suitable concentration of acid neutralizer solution, and the acid neutralizer is formulated with a portion of the water to form an acid solution having a concentration of acid neutralizer of 5 to 20%, preferably 5 to 10%, and specifically may be 5.2%, 5.5%, 5.8%, 6.0%, 6.3%, 6.5%, 6.7%, 7.0%, 7.3%, 7.5%, 7.8%, 8.0%, 8.3%, 8.5%, 8.8%, 9.0%, 9.2%, 9.5%, or 9.8%.

In some embodiments, the whitening agent may be selected from whitening agents conventional in the art, typical non-limiting examples of which include EVA emulsion, titanium dioxide, talc, and combinations thereof. The combination includes, but is not limited to, a combination of EVA emulsion and titanium dioxide, a combination of titanium dioxide and talc, a combination of EVA emulsion and talc, and a combination of EVA emulsion, titanium dioxide and talc.

In some embodiments, the humectant may be selected from humectants conventional in the art, typical, but non-limiting examples of which include glycerin, carboxymethyl modified starch, pentanediol, and combinations thereof. For example, the combinations include, but are not limited to, glycerol in combination with carboxymethyl modified starch, carboxymethyl modified starch in combination with pentanediol, glycerol in combination with pentanediol, and glycerol, carboxymethyl modified starch in combination with pentanediol.

In some embodiments, the cryoprotectant may be selected from cryoprotectants conventional in the art, wherein typical, non-limiting examples include propylene glycol, glycerol, ethylene glycol, and combinations thereof. For example, the combination includes, but is not limited to, a combination of propylene glycol and glycerol, a combination of glycerol and ethylene glycol, a combination of propylene glycol and ethylene glycol, and a combination of propylene glycol, glycerol, and ethylene glycol.

In some embodiments, the preservative and mildew inhibitor may be selected from those conventional in the art, wherein typical, non-limiting examples include sodium diacetate, benzoic acid and its sodium salt, quaternary ammonium organosilicone, cason, and combinations thereof. For example, such combinations include, but are not limited to, sodium diacetate in combination with benzoic acid and its sodium salt, sodium diacetate in combination with silicone copper quaternary ammonium salt, sodium diacetate in combination with kason, sodium diacetate, benzoic acid and its sodium salt in combination with silicone copper quaternary ammonium salt, benzoic acid and its sodium salt, silicone copper quaternary ammonium salt in combination with kason, and the like.

The wet adhesive for wallpaper and wall cloth has high adhesive force, can be used for bonding thick and heavy wall cloth, can be used for manufacturing high-viscosity high-solid-content wall cloth adhesive, and is not easy to warp edges of bonded wallpaper/wall cloth; the glue is easy to open, and the construction operation of workers is easy; in the process of alkali gelatinization, a material system is in a strong alkaline environment, the sterilization is more thorough, and the prepared wet glue has better antiseptic and mildew-proof performance, bonding performance, glue opening performance, storage stability, freezing resistance and the like than the wet glue prepared by a hot gelatinization process.

At present, some wallpaper and wall cloth wet glue prepared by using an alkali pasting process has high difficulty in preparation operation, high operation requirements on workers during use, more processes, more attention points and tracking points, and high manufacturing cost. In view of the above, according to a second aspect of the present invention, the embodiment of the present invention relates to a method for preparing alkali-gelatinized wet glue, which can be used to prepare wallpaper/wall cloth glue with high viscosity, high solid content and high quality, and the preparation method has the advantages of simple process and easy operation, and the prepared wallpaper/wall cloth wet glue has high viscosity and can be used to bond thick wall cloth; the glue is easy to open, water can be added according to the proportion of 1:1, even more than 1:1.5, the glue opening viscosity is still more than 8 ten thousand mPa.s, and the construction operation of workers is easy; in the process of alkali gelatinization, a material system is in a strong alkaline environment, the sterilization is more thorough, and the prepared wet glue has better antiseptic and mildew-proof performance, bonding performance, glue opening performance, storage stability, freezing resistance and the like than the wet glue prepared by a hot gelatinization process. The alkali gelatinized wet glue is easy to unfreeze and restore to the original state after being frozen and thawed at the temperature of-18 ℃. The quality guarantee period of the alkali gelatinized wet glue is at least one year, and the performance is still good even after three years under the condition of not unpacking.

According to the embodiment of the invention, the preparation method of the alkali-gelatinized wet glue comprises the following steps:

step 1, adding acetylated starch into water, adding water-soluble inorganic salt, and stirring to obtain a dispersed material;

step 2, adding part of the alkaline pasting agent to the dispersed material, and stirring to obtain a pre-pasted dispersed material;

step 3, adding hydroxypropyl distarch phosphate into the pre-gelatinized dispersed material, adding the residual alkaline gelatinizing agent, and stirring to obtain a gelatinized material;

and 4, adding an acid neutralizer into the gelatinized material, adjusting the pH, adding an auxiliary agent, and stirring to obtain the alkali gelatinized wet glue.

In order to enable the added raw material components to be more easily dispersed or dissolved in the material system, the raw material components to be added may be dispersed or dissolved with a part of water in advance. In step 1, the amount of acetylated, modified starch is dispersed in water in the range of 40-75% of the formula amount, for example, in the range of 40%, 45%, 50%, 55%, 60%, 65%, 68%, 70%, 71%, 72%, 74% or 75% of the formula amount. In some embodiments, the water-soluble inorganic salt is used in the form of an inorganic salt solution, e.g., the water-soluble inorganic salt is formulated as an inorganic salt solution with 55-85% water by the balance of the formulation, e.g., 55%, 60%, 65%, 70%, 71%, 75%, 80%, 83%, or 85% water by the balance of the formulation.

Specifically, in a reaction kettle or other reaction device, preferably a reactor of a stainless steel belt stirring device, the acetylated modified starch with the formula amount is dispersed into water accounting for 50-75% of the formula amount, the water-soluble inorganic salt with the formula amount (water accounting for 55-85% of the formula amount is prepared into an aqueous solution) is added, and the mixture is stirred to prepare the dispersed material. Unless otherwise specified above and below, the "balance of formula" when used with respect to water means the balance of water after addition of a portion of the water to the acetylated starch or after use of a portion of the water to disperse the acetylated starch.

In certain embodiments, step 2 is a pre-gelatinization step, step 3 is a gelatinization step, and the gelatinization temperature is 25-55 ℃, preferably 28-45 ℃; for example, 28 ℃, 29 ℃, 30 ℃, 31 ℃, 32 ℃, 33 ℃, 34 ℃, 35 ℃, 36 ℃, 37 ℃, 38 ℃, 40 ℃, 42 ℃, 43 ℃, 44 ℃ or 45 ℃.

In some embodiments, the basic pasting agent is used in the form of a basic pasting agent solution, e.g., the basic pasting agent is formulated as a basic solution with 2-15% water, e.g., 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10% water, based on the balance of the formulation. In step 2, 10-30% of the formulated amount of an alkaline solution is added to the dispersion obtained in step 1, for example, 11%, 13%, 15%, 17%, 20%, 21%, 22%, 25%, 27%, 29% or 30% of an alkaline solution. In some embodiments, the prepared alkaline solution is added to a dropping device, and is stirred at 25-35 ℃, such as 25 ℃, 26 ℃, 27 ℃, 29 ℃, 30 ℃, 31 ℃, 32 ℃, 33 ℃, 34 ℃, or 35 ℃ for 0.5-1h, such as 0.5h, 0.6h, 0.7h, 0.8h, 0.9h, or 1.0 h; obtaining the pre-gelatinized dispersed material. In some embodiments, the dropping device may be made of plastic or stainless steel.

In the step 3, the hydroxypropyl distarch phosphate with the formula amount is added into a reaction kettle to be stirred and dispersed. The hydroxypropyl distarch phosphate can be added in the form of dry powder or dispersion liquid, and after the hydroxypropyl distarch phosphate is added, a small amount of water is used for washing the inside of the reaction kettle by using a water gun, so that the dry powder or the dispersion liquid is prevented from remaining on the kettle wall or a stirrer. Dripping the prepared alkaline solution with a dripping device at 28-35 deg.C, such as 28 deg.C, 29 deg.C, 30 deg.C, 31 deg.C, 32 deg.C, 33 deg.C, 34 deg.C or 35 deg.C, and stirring for 20-60min, such as 20min, 25min, 30min, 31min, 35min, 40min, 45min, 50min, 51min, 52min, 55min, 58min, 59min or 60 min; obtaining gelatinized material. According to the preparation method embodiment of the invention, the determination of the gelatinization end point is based on whether the prepared material is in a white bright state, and when the gelatinization is finished, small white spots generated by no starch granules are taken as the gelatinization end point.

The reason why water and an alkaline pasting agent are added in portions in the above-mentioned preparation process is due to the difference in the pasting characteristics of acetylated starch and hydroxypropyl distarch phosphate. The inventor finds that the acetylated starch is difficult to be subjected to alkali gelatinization and needs to be pre-gelatinized, and hydroxypropyl distarch phosphate is easy to be gelatinized relatively, so that the sequence cannot be changed and cannot be synchronously performed.

In some embodiments, the acid neutralizer is used in the form of an acid neutralizer solution, e.g., the acid neutralizer is formulated with water at a concentration of 5 to 20% of the balance of the formula, e.g., water at 10%, 11%, 15%, 18%, 20%, 21%, 25%, 27%, 29%, or 30% of the balance of the formula. In step 4, adding an acidic neutralizing agent to the gelatinized material obtained in step 3, and adjusting the pH to 5 to 7, for example, 5.1, 5.2, 5.3, 5.5, 6.0, 6.5, 6.7, or 7.0; adding the auxiliary agent, and stirring to obtain the alkali gelatinized wet glue. In step 4, if the auxiliary agent includes a preservative and mildew inhibitor, the material after pH adjustment is preferably defoamed, and the preservative and mildew inhibitor is added when the temperature is below 50 ℃.

In one embodiment, the method for preparing the alkali-gelatinized wet gum comprises the following steps:

(1) dispersing acetylated starch in a formula amount into water accounting for 40-75% of the formula amount in a reaction kettle, adding water-soluble inorganic salt in the formula amount (preparing inorganic salt solution by using water accounting for 55-85% of the balance of the formula amount), and stirring to obtain a dispersed material;

(2) after the stirring in the step (1), adding an alkaline pasting agent (an alkaline solution prepared by water accounting for 2-15% of the balance of the formula) with the formula amount of 10-30% into a dripping device, dripping and stirring at 25-35 ℃ for 0.5-1h to obtain a pre-gelatinized dispersed material;

(3) after stirring in the step (2), adding the hydroxypropyl distarch phosphate with the formula amount into the kettle, continuously stirring and dispersing, and dropwise adding the rest of alkaline pasting agent (alkaline solution) into a dropwise adding device, and stirring for 20-60min at the temperature of 28-35 ℃ to obtain a pasted material;

(4) adding the acid neutralizer (an acid solution prepared by water accounting for 10-40% of the formula amount of the water) into the gelatinized material, and adjusting the pH of the material to 5-7; adding the whitening agent, the anti-freezing agent and the humectant in the formula amount, stirring, vacuumizing and defoaming, adding the antiseptic mildew preventive in the formula amount at the temperature below 50 ℃ (defoaming and cooling at the same time), and stirring to obtain the alkali-gelatinized wet glue.

Examples

Example 1

The alkali-gelatinized wet glue is prepared by using an alkali gelatinizing agent to prepare various modified starches through an alkali-gelatinized process under a certain condition, wherein the alkali-gelatinized wet glue is prepared from the following raw material components in parts by weight:

7 parts of acetylated starch, 16 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.5 parts of an alkaline pasting agent, 1.7 parts of an acid neutralizing agent, 0.5 part of a whitening agent, 0.3 part of a humectant, 0.1 part of an antifreeze agent, 1.4 parts of an antiseptic and mildew-proof agent and 66.5 parts of water. Wherein the water-soluble inorganic salt is sodium chloride; the alkaline pasting agent is sodium hydroxide; the acid neutralizer is hydrochloric acid; the whitening agent is titanium dioxide; the humectant is glycerol; the antifreeze agent is a mixture of propylene glycol and ethylene glycol; the antiseptic and mildew inhibitor is a mixture of sodium diacetate and cason.

The preparation method of the alkali-gelatinized wet glue comprises the following steps:

(1) dispersing acetylated starch in a formula amount into water accounting for 70% of the formula amount in a stainless steel reaction kettle, adding water-soluble inorganic salt in the formula amount (preparing inorganic salt solution by using water accounting for 80% of the formula amount of the water), and uniformly stirring to obtain a dispersed material;

(2) after the step (1) is uniformly stirred, adding an alkaline pasting agent (an alkaline solution prepared by water accounting for 5 percent of the balance of the formula) with the formula amount of 25 percent into a dripping device, and dripping and stirring at 29 ℃ for 0.5h to obtain a pre-pasted dispersed material;

(3) after the step (2) is uniformly stirred, adding the hydroxypropyl distarch phosphate with the formula amount into the kettle, continuously stirring and uniformly dispersing, and dropwise adding the rest of alkaline pasting agent (alkaline solution) into a dropwise adding device at 29 ℃ and stirring for 30min to obtain a pasted material;

(4) adding the acid neutralizer (prepared into an acid solution by using water accounting for 15% of the balance of the water formula) in the formula amount into the gelatinized material, and adjusting the pH value of the material to 5.0; adding the whitening agent, the anti-freezing agent and the humectant in the formula amount, stirring, vacuumizing and defoaming, adding the antiseptic and mildew-proof agent in the formula amount at a temperature below 50 ℃ (defoaming and cooling at the same time), and stirring uniformly to prepare the alkali-gelatinized wet glue.

Example 2

13 parts of acetylated starch, 7 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.0 part of alkaline pasting agent, 1.2 parts of acidic neutralizing agent, 0.5 part of whitening agent, 0.5 part of humectant, 0.1 part of antifreeze agent, 1.0 part of antiseptic and mildew-proof agent and 70.7 parts of water. Wherein the water-soluble inorganic salt is sodium chloride; the alkaline pasting agent is calcium hydroxide; the acid neutralizer is oxalic acid; the whitening agent is talcum powder; the humectant is carboxymethyl modified starch; the antifreeze agent is propylene glycol; the antiseptic and mildew inhibitor is organosilicon copper quaternary ammonium salt.

(1) dispersing acetylated starch in a formula amount into water accounting for 72% of the formula amount in a stainless steel reaction kettle, adding water-soluble inorganic salt in the formula amount (inorganic salt solution is prepared by water accounting for 75% of the formula amount of the water), and uniformly stirring to obtain a dispersed material;

(2) after the step (1) is uniformly stirred, adding an alkaline pasting agent (an alkaline solution prepared by water accounting for 8 percent of the balance of the formula) with the formula amount of 20 percent into a dripping device, and dripping and stirring for 0.5h at the temperature of 30 ℃ to obtain a pre-pasted dispersed material;

(3) after the step (2) is uniformly stirred, adding the hydroxypropyl distarch phosphate with the formula amount into the kettle, continuously stirring and uniformly dispersing, and dropwise adding the rest of alkaline pasting agent (alkaline solution) into a dropwise adding device at 30 ℃ and stirring for 30min to obtain a pasted material;

(4) adding the acid neutralizer (prepared into an acid solution by using water accounting for 17% of the formula amount of the water) into the gelatinized material, and adjusting the pH of the material to 5.5; adding the whitening agent, the anti-freezing agent and the humectant in the formula amount, stirring, vacuumizing and defoaming, adding the antiseptic and mildew-proof agent in the formula amount at a temperature below 50 ℃ (defoaming and cooling at the same time), and stirring uniformly to prepare the alkali-gelatinized wet glue.

The alkali-gelatinized wet gum obtained in example 2 was packaged into a finished product as shown in fig. 1.

Example 3

9 parts of acetylated starch, 6 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.2 parts of alkaline pasting agent, 1.3 parts of acidic neutralizing agent, 0.5 part of whitening agent, 0.3 part of humectant, 0.1 part of antifreeze agent, 1.5 parts of antiseptic and mildew-proof agent and 75.1 parts of water. Wherein the water-soluble inorganic salt is sodium chloride; the alkaline pasting agent is sodium carbonate; the acid neutralizer is oxalic acid; the whitening agent is EVA emulsion; the humectant is a mixture of glycerol and pentanediol; the antifreeze agent is ethylene glycol; the antiseptic and mildew inhibitor is benzoic acid.

(1) dispersing acetylated starch in a formula amount into water accounting for 73.6% of the formula amount in a stainless steel reaction kettle, adding water-soluble inorganic salt in the formula amount (inorganic salt solution prepared by water accounting for 78% of the formula amount of the water), and uniformly stirring to obtain a dispersed material;

(2) after the step (1) is uniformly stirred, adding an alkaline pasting agent (an alkaline solution prepared by water accounting for 6 percent of the balance of the formula) with the formula amount of 30 percent into a dripping device, and dripping and stirring for 0.5h at 33 ℃ to obtain a pre-pasted dispersed material;

(3) after the step (2) is uniformly stirred, adding the hydroxypropyl distarch phosphate with the formula amount into the kettle, continuously stirring and uniformly dispersing, and dropwise adding the rest of alkaline pasting agent (alkaline solution) into a dropwise adding device at 33 ℃ and stirring for 30min to obtain a pasted material;

(4) adding the acid neutralizer (prepared into an acid solution by using water accounting for 16 percent of the balance of the water formula) in the formula amount into the gelatinized material, and adjusting the pH value of the material to 6.0; adding the whitening agent, the anti-freezing agent and the humectant in the formula amount, stirring, vacuumizing and defoaming, adding the antiseptic and mildew-proof agent in the formula amount at a temperature below 50 ℃ (defoaming and cooling at the same time), and stirring uniformly to prepare the alkali-gelatinized wet glue.

Example 4

8 parts of acetylated starch, 5 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.1 parts of alkaline pasting agent, 1.2 parts of acidic neutralizing agent, 0.5 part of whitening agent, 0.3 part of humectant, 0.1 part of antifreeze agent, 1.4 parts of antiseptic and mildew-proof agent and 77.4 parts of water.

The raw material components of the alkali gelatinized wet glue in the embodiment are adjusted by the same weight parts as the embodiment 2.

The process for preparing the alkali-gelatinized wet gel of this example is the same as in example 2.

Example 5

7 parts of acetylated starch, 4 parts of hydroxypropyl distarch phosphate, 5 parts of water-soluble inorganic salt, 1.0 part of alkaline pasting agent, 1.0 part of acidic neutralizing agent, 0.5 part of whitening agent, 0.3 part of humectant, 0.1 part of antifreeze agent, 1.4 parts of antiseptic and mildew-proof agent and 79.7 parts of water.

Examples 1-5 parts by weight of base gelatinized wet gum starting components are shown in table 1.

Table 1 examples 1-5 parts by weight of base gelatinized wet gum stock components

Comparative example 1

The comparative example is a certain glutinous rice wallpaper wet glue produced by a commercial hot pasting process, and the solid content is 27%.

Comparative example 2

The comparative example is a certain seamless wall cloth adhesive produced by a commercial hot pasting process, and the curing amount is 22%.

Test example

The test examples respectively test the performance of the wallpaper wet glue of each example and the comparative example. The test method is as follows:

solid content: the alkali-gelatinized wet glue prepared in each example and the commercially available wet glue for wallpaper and wall cloth of comparative examples 1 and 2 were placed in an oven and dried to constant weight, and the mass percentage of the solid content of the wet glue sample in the total amount was calculated.

The glue opening performance is as follows: and (3) respectively adding water into the alkali gelatinized wet glue prepared in each example and the commercially available wallpaper wall cloth wet glue of comparative examples 1 and 2 according to the proportion of 1:1, recording the glue opening condition, and observing whether particles exist in the state after water adding and whether the glue solution is fine and smooth, wherein the alkali gelatinized wet glue of examples 2, 3 and 4 after water adding and glue opening are shown in figures 2, 3 and 4.

Peel strength: the peel strength of the samples after the glue opening and the samples after the glue opening are tested by a tensile machine, wherein the larger the peel strength is, the better the bonding strength is.

Viscosity: the viscosity of the example after the 1:1 water-blended gel-breaking and the viscosity of the comparative example without the gel-breaking were measured by using an NDJ-1 rotational viscometer, and the higher the viscosity, the thicker the state after the water-blended gel-breaking, the NDJ-1 rotational viscometer test is shown in FIG. 5, and FIG. 6 is a result of the test of the example 2 after the gel-breaking.

Initial adhesion: the initial adhesion of the samples of the alkali gelatinized wet glue prepared in each example and the samples of the commercially available wallpaper wall cloth wet glue of comparative examples 1 and 2 after glue opening are tested by an initial adhesion tester, and the higher the initial adhesion, the stronger the fixability during initial adhesion.

Freezing resistance: freezing the sample in refrigerator at-18 deg.C for 24 hr, taking out, thawing at normal temperature, observing whether the sample is in original state, and performing gel breaking test to determine whether its viscosity is stable

Heat resistance: and (3) putting the sample which is not subjected to gel opening into an oven, keeping the temperature at 45 ℃ for 15 days, taking out the sample, radiating at normal temperature, observing whether the sample is in an original state or not, and then, carrying out gel opening to test whether the viscosity of the sample is stable or not.

Storage stability: the sample is kept for regular observation for the existence of water or mildew.

The test results are shown in Table 2.

Table 2 properties of the alkali-gelatinized wet glues of examples 1 to 5 and the wallpaper wall coating glue of comparative example

As can be seen from Table 1, the alkali-gelatinized wallpaper wall cloth wet glue has better glue-opening performance, bonding strength, consistency after glue opening and fixity during initial bonding than the commercial wet glue under the condition of equivalent solid content, and has better low-temperature, high-temperature and storage stability than the commercial wet glue. The wallpaper wall cloth wet glue is prepared by an alkali pasting process instead of a direct simple heating pasting mode, the wall paper wall cloth is easy to penetrate glue under the condition of low viscosity of the general hot pasting wet glue, and the alkali pasting wet glue in the embodiment 5 is still not easy to penetrate glue under the condition of low viscosity.

Also in accordance with the present invention, the acetylated starch and hydroxypropyl distarch phosphate in examples 3 and 5 were reversed, i.e., increasing the amount of hydroxypropyl distarch phosphate and decreasing the amount of acetylated starch, to produce a wet gum with increased viscosity and softer hand. Workers can adjust the construction according to actual construction requirements.

The alkali-gelatinized wet wallpaper wall cloth glue disclosed by the invention not only ensures the advantages of high glue opening amount, high fine smoothness and easy glue opening, but also avoids the problem that the common hot-gelatinized wet glue is difficult to open; the problems that the traditional hot-pasting wet glue is poor in adhesive force, low in peeling strength and insufficient in fine smoothness, and the wallpaper wall cloth is easy to warp edges are solved; in addition, the anti-mold capacity of the wet glue of the alkali-gelatinized wallpaper wall cloth is superior to that of the wet glue produced by the traditional hot-gelatinization process.

The foregoing is a more detailed description of the present invention that is presented in conjunction with specific embodiments, and the practice of the invention is not to be considered limited to those descriptions. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.

Claims

1. The alkali-gelatinized wet glue is characterized by being prepared from the following raw material components in parts by weight:

2. the alkali-gelatinized wet glue according to claim 1, which is prepared from the following raw material components in parts by weight: 10-20 parts of acetylated starch, 5-10 parts of hydroxypropyl distarch phosphate, 4-8 parts of water-soluble inorganic salt, 0.5-2 parts of alkaline pasting agent, 0.5-2 parts of acid neutralizing agent, 0.9-4 parts of auxiliary agent and 63-75 parts of water.

3. The alkali-gelatinized wet gum as claimed in claim 1 or 2, wherein the acetylated starch comprises one or more of acetylated tapioca starch, acetylated waxy corn starch, acetylated wheat starch and acetylated potato starch.

4. The alkali-gelatinized wet gum as claimed in claim 1 or 2, wherein the hydroxypropyl distarch phosphate comprises one or more of hydroxypropyl phosphate-modified tapioca starch, hydroxypropyl phosphate-modified corn starch, hydroxypropyl phosphate-modified wheat starch and hydroxypropyl phosphate-modified potato starch.

5. The alkali-gelatinized wet gum as claimed in claim 1 or 2, wherein the water-soluble inorganic salt comprises one or more of a chloride salt, a nitrate salt, a sodium salt, a sulfate salt and a phosphate salt.

6. The alkali-gelatinized wet gum as claimed in claim 1 or 2, wherein the alkali-gelatinizing agent comprises one or more of potassium hydroxide, sodium hydroxide, magnesium hydroxide, calcium hydroxide, sodium phosphate and sodium carbonate.

7. The alkali gelatinized wet glue of claim 1 or 2, wherein the acid neutralizer comprises one or more of nitric acid, hydrochloric acid, oxalic acid, and phosphoric acid.

8. The alkali-gelatinized wet glue according to claim 1 or 2, wherein the auxiliaries include one or more of a whitening agent, a humectant, an antifreeze agent and a preservative and mildewproof agent.

9. The process for the preparation of alkali-gelatinized wet gum as claimed in any one of claims 1 to 8, comprising the steps of:

adding the acetylated starch into water, adding water-soluble inorganic salt, and stirring to obtain a dispersed material;

and adding an acid neutralizer into the gelatinized material, adjusting the pH, adding an auxiliary agent, and stirring to obtain the alkali gelatinized wet glue.

10. Use of the alkali-gelatinised wet glue of any one of claims 1 to 8 as a wallpaper/wall covering adhesive.