A putty adhesive for interior decoration of buildings and its preparation method

Abstract

This invention relates to a putty adhesive for interior building decoration and its preparation method. The putty adhesive for interior building decoration comprises the following raw materials: soy protein isolate, polyvinyl alcohol, urea, silica sol, coupling agent, and water. This invention also provides a method for preparing the putty adhesive for interior building decoration according to this invention, comprising the following steps: adding soy protein isolate to water, adjusting the pH value with sodium hydroxide, then adding urea, heating to react, and obtaining a soy protein modified liquid; adding polyvinyl alcohol to water, heating, and cooling to obtain a polyvinyl alcohol aqueous solution; mixing the soy protein modified liquid and the polyvinyl alcohol aqueous solution, adding silica sol and a coupling agent, polymerizing, and cooling to obtain the putty adhesive for interior building decoration. This invention solves the problem that existing putty adhesives for interior building decoration contain formaldehyde, which pollutes the environment and affects human health.

Description

Technical Field

[0001] This invention relates to the field of composite polymer materials technology, specifically to a putty adhesive for interior decoration of buildings and its preparation method. Background Technology

[0002] Interior decoration is a crucial part of home renovation, and also one of the biggest sources of pollution in home renovation today. Traditional interior decoration often involves first applying putty to the walls, then sanding it smooth after it dries, before applying various wall paints or wallpaper. The putty used for interior wall decoration mainly consists of adhesive, various inorganic fillers, water, and additives. The adhesive primarily acts as a binder in the putty, making it an adhesive paste that is easy to apply to the wall surface. After the putty has cured and dried, it acts as a binder, forms a waterproof film, and resists cracking.

[0003] Currently, the adhesive used in the production of interior decoration putty, commonly known as glue, primarily forms films with polyvinyl alcohol formaldehyde (PVA), which is produced by the condensation of PVA and formaldehyde. Therefore, this glue contains a large amount of free formaldehyde, resulting in formaldehyde pollution and other safety and environmental defects in traditional interior decoration putty. With increasing health awareness, people are paying more attention to choosing environmentally friendly, formaldehyde-free building materials for home decoration. Bio-based adhesives, due to their lack of formaldehyde pollution, are gaining popularity.

[0004] CN 111944480 A discloses a silica sol soybean protein adhesive for fiberboard production and its preparation method. The method involves dissolving sodium tetraborate and water in a reaction vessel, adding soybean protein isolate and urea, heating under stirring to carry out a modification reaction, and after cooling, adding silica sol and polyvinyl alcohol solution, followed by thorough stirring to prepare the silica sol soybean protein adhesive for fiberboard production. Fiberboard produced using this method exhibits high strength, good moisture resistance, and no formaldehyde pollution. The preparation process is simple, low-cost, and environmentally friendly, making it suitable for industrial production. However, because this silica sol soybean protein adhesive is used to bond fine fiber powder and requires spraying and hot-pressing drying processes, it demands high solids content and bonding strength. For interior decoration, putty cures naturally and requires subsequent sanding, making this adhesive unsuitable for building interior decoration. Summary of the Invention

[0005] The purpose of this invention is to provide a putty adhesive for interior decoration of buildings and its preparation method, so as to solve the problem that existing putty adhesives for interior decoration of buildings contain formaldehyde, which pollutes the environment and affects human health.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A putty adhesive for interior decoration of buildings, comprising, by weight, the following raw materials: 5-10 parts by weight of soy protein isolate, 6-14 parts by weight of polyvinyl alcohol, 0.5-3 parts by weight of urea, 0.5-2 parts by weight of silica sol, 0.2-0.3 parts by weight of coupling agent and 200 parts by weight of water.

[0008] Based on the aforementioned technical means, the putty adhesive produced using soy protein isolate and polyvinyl alcohol, obtained through processing from natural biological raw materials, is free of pollutants such as formaldehyde, and no toxic or harmful substances are added to the raw materials. This prevents the generation and release of toxic and harmful substances, effectively avoiding environmental pollution and improving human health and safety. Soy protein isolate, as a peptide chain polymer with an amide structure, has the advantages of high functional group activity and good cross-linking film-forming properties. At the same time, by adding coupling agents and silica sol, the water resistance and weather resistance of the protein bio-based adhesive after curing are effectively improved.

[0009] Preferably, the coupling agent is N-(2-aminoethyl)-3-aminopropyltrimethoxysilane.

[0010] Preferably, the silica sol has a solid content of 20-30 wt% and a pH value of 7-9.

[0011] Preferably, by weight, it comprises the following raw materials: 6-8 parts by weight of soy protein isolate, 8-12 parts by weight of polyvinyl alcohol, 0.5-3 parts by weight of urea, 0.5-2 parts by weight of silica sol, 0.2-0.3 parts by weight of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and 200 parts by weight of water.

[0012] Preferably, by weight, it comprises the following raw materials: 7 parts by weight of soy protein isolate, 10 parts by weight of polyvinyl alcohol, 1.5 parts by weight of urea, 1.5 parts by weight of silica sol, 0.25 parts by weight of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and 200 parts by weight of water.

[0013] This invention also provides a method for preparing the putty adhesive for interior decoration of buildings, comprising the following steps:

[0014] Soy protein isolate was added to water, the pH was adjusted with sodium hydroxide, urea was added, and the mixture was heated to react and obtain a modified soy protein solution.

[0015] Polyvinyl alcohol is added to water, heated, and cooled to obtain an aqueous solution of polyvinyl alcohol.

[0016] Soy protein modified liquid and polyvinyl alcohol aqueous solution are mixed, silica sol and coupling agent are added, polymerization reaction is carried out, and cooling is performed to obtain putty adhesive for building interior decoration.

[0017] The main differences between this application and the soybean protein adhesive disclosed in CN 111944480 A are as follows:

[0018] 1) The reaction principles in the bonding process are different: In this application, the prepared putty is mainly used to bond various inorganic fillers. The bonding agent is the composite macromolecular product obtained by the coupling reaction of protein and polyvinyl alcohol, namely protein-based polyvinyl alcohol. The role of the coupling agent is to connect the protein macromolecule and the polyvinyl alcohol macromolecule. At the same time, silica sol is grafted onto the composite macromolecule through its coupling effect to improve the bonding strength of the putty. The preparation process of the putty involves a chemical reaction process. In this application, the high viscosity formed by the composite macromolecule is used to bond the inorganic fillers in the putty, with physical action being dominant and chemical bonding being secondary. In contrast, in the soybean protein adhesive in CN 111944480 A, the role of protein, silica sol, etc. is mainly to react chemically with fibers, while polyvinyl alcohol mainly plays an auxiliary role in adjusting the leveling, viscosity, and workability of the adhesive. Moreover, the soybean protein adhesive has a high solid content.

[0019] 2) The construction scenarios and application processes are different: In this application, the putty produced by the prepared putty adhesive is cured by natural drying without hot pressing. The adhesive mainly binds the inorganic fillers through the high viscosity formed during its own water loss curing process. The strength requirement is not high, which facilitates subsequent sanding. However, the soybean protein adhesive in CN 111944480 A is applied by spraying. It requires a high solid content but a low viscosity. After mixing, it undergoes a hot pressing drying process. Hot pressing provides chemical bonding conditions and adhesive strength for the reaction of silica sol and protein with fibers. The strength requirement is high.

[0020] 3) Different raw materials: In the soybean protein adhesive in CN 111944480 A, sodium tetraborate is used to preserve the protein; in this application, the protein has lost its nutritional value through coupling reaction, so there is no need to add it. In addition, the amount of polyvinyl alcohol used in this application is large, which easily forms a gel with sodium tetraborate, thus making sodium tetraborate unusable in the putty adhesive of this application.

[0021] Preferably, the pH value is adjusted to 9-10 using sodium hydroxide;

[0022] After adding urea, the temperature of the heating reaction is 58℃~65℃, and the heating reaction time is 40~60min.

[0023] Preferably, the polyvinyl alcohol is added to water, heated to 95°C to dissolve the polyvinyl alcohol, and then cooled to 25°C to 60°C to obtain a polyvinyl alcohol aqueous solution.

[0024] Preferably, the polymerization reaction temperature is 55℃~65℃, and the polymerization reaction time is 15~45min.

[0025] Preferably, the polymerization reaction is carried out at a temperature of 60°C for 30 minutes.

[0026] The beneficial effects of this invention are:

[0027] The putty adhesive of this invention for interior decoration uses soy protein isolate and polyvinyl alcohol, obtained from natural biological raw materials. This ensures that the putty adhesive is free of pollutants such as formaldehyde, and no toxic or harmful substances are added to the raw materials, preventing the generation and release of toxic and harmful substances, effectively avoiding environmental pollution, and improving human health and safety. Soy protein isolate, as a peptide chain polymer with an amide structure, has the advantages of high functional group activity and good cross-linking film-forming properties. At the same time, by adding coupling agents and silica sol, the water resistance and weather resistance of the protein bio-based adhesive after curing are effectively improved. Furthermore, soy protein isolate and polyvinyl alcohol have the advantages of abundant sources, biodegradability, no plastic pollution, and low price, providing a favorable guarantee for the industrial production of bio-based adhesives.

[0028] The present invention discloses a method for preparing a putty adhesive for interior building decoration. First, a modified soy protein isolate solution and a polyvinyl alcohol (PVA) aqueous solution are prepared using soy protein isolate and PVA, respectively. This solves the problem of inconsistent reaction temperatures between the two solutions and creates suitable reaction conditions for the coupling reaction of the two substances to prepare a soy protein-PVA composite polymer. Second, a coupling agent is added to link the soy protein isolate and PVA, while silica sol is added to graft onto the protein macromolecules via hydrolysis and cross-linking, effectively improving the water resistance and weather resistance of the cured protein-based adhesive. Third, by rationally controlling the ratio of PVA, soy protein isolate, silica sol, and coupling agent, as well as the modification time, polymerization temperature, and time of soy protein isolate, the prepared putty adhesive for interior building decoration exhibits advantages such as no lumps, uniform mixing, excellent low-temperature storage stability, strong workability, no cracks in the initial drying stage, easy sanding, good water resistance, and good bonding strength. Furthermore, it features simple operation and low production cost, making it more valuable for industrial production and possessing potential application value in the field of composite polymer materials technology. Detailed Implementation

[0029] The following description, with reference to preferred embodiments, illustrates the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are merely illustrative of the present invention and not intended to limit the scope of protection of the present invention.

[0030] Example 1

[0031] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0032] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0033] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0034] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0035] Example 2

[0036] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0037] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0038] S2. Add 14 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0039] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0040] Example 3

[0041] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0042] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0043] S2. Add 6 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0044] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0045] Example 4

[0046] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0047] S1. Add 5 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0048] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0049] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0050] Example 5

[0051] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0052] S1. Add 10 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide. Then add 1.5 kg of urea and heat to 60°C under stirring. React for 50 minutes to obtain a modified soy protein solution.

[0053] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0054] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0055] Example 6

[0056] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0057] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0058] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0059] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 0.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0060] Example 7

[0061] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0062] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0063] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0064] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 2.0 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0065] Example 8

[0066] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0067] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0068] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0069] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 55°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0070] Example 9

[0071] A method for preparing putty adhesive for interior decoration of buildings, comprising the following steps:

[0072] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0073] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0074] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 65°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0075] Comparative Example 1

[0076] A method for preparing a conventional putty adhesive includes the following steps:

[0077] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0078] S2. Add 16 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0079] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0080] Comparative Example 2

[0081] A method for preparing a conventional putty adhesive includes the following steps:

[0082] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0083] S2. Add 5 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0084] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0085] Comparative Example 3

[0086] A method for preparing a conventional putty adhesive includes the following steps:

[0087] S1. Add 12Kg of soy protein isolate and 100Kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5Kg of urea. Heat to 60℃ under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0088] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0089] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0090] Comparative Example 4

[0091] A method for preparing a conventional putty adhesive includes the following steps:

[0092] S1. Add 4 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0093] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0094] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0095] Comparative Example 5

[0096] A method for preparing a conventional putty adhesive includes the following steps:

[0097] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0098] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0099] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 3Kg of silica sol and 0.25Kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60℃ for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0100] Comparative Example 6

[0101] A method for preparing a conventional putty adhesive includes the following steps:

[0102] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0103] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0104] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 0.3 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0105] Comparative Example 7

[0106] A method for preparing a conventional putty adhesive includes the following steps:

[0107] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 0.3 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0108] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0109] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0110] Comparative Example 8

[0111] A method for preparing a conventional putty adhesive includes the following steps:

[0112] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 30 minutes to obtain a modified soy protein solution.

[0113] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0114] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0115] Comparative Example 9

[0116] A method for preparing a conventional putty adhesive includes the following steps:

[0117] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0118] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0119] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.1 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0120] Comparative Example 10

[0121] A method for preparing a conventional putty adhesive includes the following steps:

[0122] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0123] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0124] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 50°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0125] Comparative Example 11

[0126] A method for preparing a conventional putty adhesive includes the following steps:

[0127] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0128] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0129] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 60°C for 10 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0130] Comparative Example 12

[0131] A method for preparing a conventional putty adhesive includes the following steps:

[0132] S1. Add 7 kg of soy protein isolate and 100 kg of water to a reaction vessel and stir to disperse. Adjust the pH value to 10 with sodium hydroxide, then add 1.5 kg of urea. Heat to 60°C under stirring and react for 50 minutes to obtain a modified soy protein solution.

[0133] S2. Add 10 kg of polyvinyl alcohol and 100 kg of water to a reaction vessel, heat to 95°C under stirring to completely dissolve the polyvinyl alcohol, and then cool to 60°C to obtain an aqueous solution of polyvinyl alcohol.

[0134] S3. Mix the soybean protein modified liquid obtained in S1 and the polyvinyl alcohol aqueous solution obtained in S2, then add 1.5 kg of silica sol and 0.25 kg of coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, stir and mix evenly, then polymerize at 70°C for 30 minutes, cool to room temperature, and obtain putty for building interior decoration.

[0135] Detection and Analysis

[0136] The putty adhesives for interior decoration prepared in Examples 1 to 7, and the conventional putty adhesives prepared in Comparative Examples 1 to 12 were used to process interior wall putty. The performance indicators of the putty were tested (the test methods were performed in accordance with JG / T 298-2010 "Putty for Interior Decoration of Buildings"). The results are shown in Table 1.

[0137] Table 1. Properties of the coatings prepared in Examples 1-7 and Comparative Examples 1-12 and performance indicators of the prepared coated papers.

[0138]

[0139]

[0140]

[0141] Note: The row numbers in the table are: JG / T 298-2010 "Building Interior Putty", and the listed indicators are the differences that can be affected by changes in putty adhesive.

[0142] Analysis of the data in Table 1 shows that the putty made from the putty adhesives obtained in Examples 1-7 of this invention for interior decoration has good properties. All performance indicators of the putty meet or exceed the relevant technical requirements specified in the industry standard JG / T 298-2010 "Putty for Interior Building Use". Among them, the putty obtained in Example 1 has the best overall performance. In contrast, in Comparative Example 1, due to excessive polyvinyl alcohol content, the putty was too thick, resulting in clumping and a long surface drying time. In Comparative Example 2, due to insufficient polyvinyl alcohol content, the putty had poor adhesion, slight powdering during film formation, and low bonding strength. In Comparative Example 3, due to excessive soy protein isolate content, the reaction was excessive, resulting in poor crack resistance and cracks in the initial drying stage, and powdering during film formation. In Comparative Example 4, due to insufficient soy protein isolate content, the polymerization effect was poor, the surface drying time was long, and the putty film cracked. In Comparative Example 5, due to excessive silica sol, the putty clumped, became too thick, and exhibited cracking during film formation. The bonding strength was high but excessively high, affecting sanding. In Comparative Example 6, due to insufficient silica sol, slight cracks appeared during initial drying, and the putty's bonding strength was low after drying. In Comparative Example 7, due to insufficient urea, the protein did not dissolve well, resulting in clumping of the putty. The putty film cracked, powdered, and exhibited low bonding strength. In Comparative Example 8, due to insufficient protein modification time, the protein was not completely dissolved, leading to uneven putty preparation, easy deterioration, poor crack resistance during initial drying, poor film formation, powdering, and low bonding strength. In Comparative Example 9, due to insufficient coupling agent, the polymerization effect between protein and polyvinyl alcohol was poor, resulting in poor crack resistance and film formation during initial drying, and cracking. In Comparative Example 10, the polymerization temperature of the polyvinyl alcohol solution and protein-modified liquid was too low, resulting in poor polymerization. The formulated putty exhibited poor low-temperature stability, was prone to deterioration, had poor crack resistance in the initial drying stage, developed cracks, and exhibited poor film formation, blistering, cracking, and powdering, with low bonding strength. In Comparative Example 11, the polymerization time of the polyvinyl alcohol solution and protein-modified liquid was too short, resulting in poor polymerization. The formulated putty exhibited poor low-temperature stability, was prone to deterioration, had poor crack resistance in the initial drying stage, developed cracks, and exhibited poor film formation, blistering, cracking, and powdering, with low bonding strength. In Comparative Example 12, the polymerization temperature of the polyvinyl alcohol solution and protein-modified liquid was too high, resulting in poor polymerization. The formulated putty exhibited poor low-temperature stability, was prone to deterioration, had poor crack resistance in the initial drying stage, developed cracks, and exhibited poor film formation, blistering, cracking, and powdering, with low bonding strength. This demonstrates that in the preparation method of the putty adhesive for building interior decoration of the present invention, the ratio of polyvinyl alcohol, soy protein isolate, silica sol and coupling agent, as well as the modification time, polymerization temperature and time of soy protein isolate are all important parameters affecting the performance of the putty adhesive.

[0143] In summary, the putty adhesive for interior building decoration of the present invention uses soy protein isolate and polyvinyl alcohol raw materials obtained from natural biological raw materials. This ensures that the putty adhesive produced is free of pollutants such as formaldehyde, and no toxic or harmful substances are added to the raw materials, preventing the generation and release of toxic and harmful substances, effectively avoiding environmental pollution, and improving human health and safety. Soy protein isolate, as a peptide chain polymer with an amide structure, has the advantages of high functional group activity and good cross-linking film-forming properties. At the same time, by adding coupling agents and silica sol, the water resistance and weather resistance of the protein bio-based adhesive after curing are effectively improved. Furthermore, soy protein isolate and polyvinyl alcohol have the advantages of abundant sources, biodegradability, no plastic pollution, and low price, providing a favorable guarantee for the industrial production of bio-based adhesives.

[0144] The present invention discloses a method for preparing a putty adhesive for interior building decoration. First, a modified soy protein isolate solution and a polyvinyl alcohol (PVA) aqueous solution are prepared using soy protein isolate and PVA, respectively. This solves the problem of inconsistent reaction temperatures between the two solutions and creates suitable reaction conditions for the coupling reaction of the two substances to prepare a soy protein-PVA composite polymer. Second, a coupling agent is added to link the soy protein isolate and PVA, while silica sol is added to graft onto the protein macromolecules via hydrolysis and cross-linking, effectively improving the water resistance and weather resistance of the cured protein-based adhesive. Third, by rationally controlling the ratio of PVA, soy protein isolate, silica sol, and coupling agent, as well as the modification time, polymerization temperature, and time of soy protein isolate, the prepared putty adhesive for interior building decoration exhibits advantages such as no lumps, uniform mixing, excellent low-temperature storage stability, strong workability, no cracks in the initial drying stage, easy sanding, good water resistance, and good bonding strength. Furthermore, it features simple operation and low production cost, making it more valuable for industrial production and possessing potential application value in the field of composite polymer materials technology.

[0145] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A method for preparing putty adhesive for interior building decoration, characterized in that, Includes the following steps: Soy protein isolate was added to water, the pH was adjusted with sodium hydroxide, urea was added, and the mixture was heated to react and obtain a modified soy protein solution. The pH value is adjusted to 9-10 with sodium hydroxide; after adding urea, the temperature of the heating reaction is 58 ℃-65 ℃, and the heating reaction time is 40-60 min. Polyvinyl alcohol is added to water, heated, and cooled to obtain an aqueous solution of polyvinyl alcohol. Soy protein modified solution and polyvinyl alcohol aqueous solution were mixed, silica sol and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane were added, polymerization reaction was carried out, and the mixture was cooled to obtain putty adhesive for building interior decoration; the polymerization reaction temperature was 55℃~65℃, and the polymerization reaction time was 15~45 min. The putty adhesive used for interior decoration of buildings comprises, by weight, the following raw materials: 6-8 parts by weight of soy protein isolate, 8-12 parts by weight of polyvinyl alcohol, 0.5-3 parts by weight of urea, 0.5-2 parts by weight of silica sol, 0.2-0.3 parts by weight of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and 200 parts by weight of water.

2. The method for preparing putty adhesive for interior decoration of buildings according to claim 1, characterized in that, The silica sol has a solid content of 20–30 wt% and a pH value of 7–9.

3. The method for preparing putty adhesive for interior decoration of buildings according to claim 1, characterized in that, By weight, it comprises the following ingredients: 7 parts by weight of soy protein isolate, 10 parts by weight of polyvinyl alcohol, 1.5 parts by weight of urea, 1.5 parts by weight of silica sol, 0.25 parts by weight of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and 200 parts by weight of water.

4. The method for preparing putty adhesive for interior decoration of buildings according to claim 1, characterized in that, The process involves adding polyvinyl alcohol to water, heating it to 95°C to dissolve the polyvinyl alcohol, and then cooling it to 25°C~60°C to obtain a polyvinyl alcohol aqueous solution.

5. The method for preparing putty adhesive for interior decoration of buildings according to claim 4, characterized in that, The polymerization reaction was carried out at a temperature of 60 °C for 30 min.

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