High-bonding-strength back adhesive emulsion as well as raw material composition, preparation method and application of high-bonding-strength back adhesive emulsion

Abstract

The invention discloses a high-bonding-strength back adhesive emulsion as well as a raw material composition, a preparation method and application thereof. The high-bonding-strength back adhesive emulsion comprises the following components in parts by weight: 6-10 parts of a hard monomer, 31-35 parts of a soft monomer, 1.8-2.2 parts of a protective monomer, 0.08-0.12 part of an organic silicon monomer, 2.3-2.7 parts of an emulsifier and 0.18-0.22 part of an initiator, the protective monomer comprises acrylamide and acrylic acid in a mass ratio of (0.6-1): 1. The back adhesive emulsion disclosed by the invention has good bonding strength and emulsion stability, and the used raw materials are conventional raw materials and conventional dosages, so that the cost is relatively low.

Description

Technical Field

[0001] The invention belongs to the technical field of coating, and in particular relates to a high-bonding-strength adhesive latex, a raw material composition thereof, and a preparation method and application thereof. Background Art

[0002] Adhesive emulsion is a water-based adhesive, mainly composed of polyacrylic resin, additives and water. It has good adhesion, high bonding strength, environmental protection, and easy processing. Adhesive emulsion is widely used in stationery manufacturing, automotive interior manufacturing, packaging, furniture manufacturing, tile pasting and other fields, providing convenient and practical bonding solutions for all walks of life. However, the existing water-based acrylic adhesive emulsion cannot have both adhesion and emulsion stability. Traditional water-based acrylic emulsions have poor stability when coated on substrates, resulting in demulsification and gelation, which affects the subsequent bonding strength and reduces the adhesive coating effect.

[0003] In order to solve this problem, the art generally changes the latex particles or structure in the emulsion to improve its coating stability and bonding strength on the substrate. For example, the performance of the latex particles is improved by changing the ratio of the hard segment and the soft segment in the latex particles, or by introducing functional monomers into the preparation system for modification.

[0004] Conventional methods for improving the stability of latex particles may increase the manufacturing cost of the emulsion and sacrifice the bonding strength and polymerization degree of the latex particles. Therefore, how to ensure the stability of the latex particles in the emulsion so that it has a good coating effect while not affecting its bonding strength is a technical problem that needs to be solved in this field. Summary of the invention

[0005] To solve the above technical problems, the present invention provides a high-bonding strength adhesive latex, a raw material composition, a preparation method and an application thereof. The adhesive latex provided by the present invention has good bonding strength and emulsion stability, and the raw materials used are all conventional raw materials and conventional amounts, and the cost is low.

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

[0007] In one aspect, the present invention provides a raw material composition of a high bonding strength backing adhesive latex, which comprises the following components in parts by weight:

[0008] 6 to 10 parts of hard monomer, 31 to 35 parts of soft monomer, 1.8 to 2.2 parts of protective monomer, 0.08 to 0.12 parts of silicone monomer, 2.3 to 2.7 parts of emulsifier and 0.18 to 0.22 parts of initiator;

[0009] The protective monomers include acrylamide and acrylic acid in a mass ratio of (0.6-1):1.

[0010] In some embodiments, the mass ratio of the hard monomer to the soft monomer is 1:(3.1-5.9);

[0011] In some embodiments, the hard monomer includes methyl methacrylate and styrene monomers;

[0012] In some embodiments, the soft monomer includes n-butyl acrylate and isooctyl acrylate in a mass ratio of 1:(0.82-0.85);

[0013] In some embodiments, the organosilicon monomer is a silane monomer with a vinyl group;

[0014] In some embodiments, the emulsifier is selected from at least one of disodium ethoxylated fatty alcohol yellow succinate half ester, sodium salt of alkyl alcohol monosulfosuccinate, and disodium lauryl alcohol polyoxyethylene ether sulfosuccinate.

[0015] In some embodiments, the weight proportion of the methyl methacrylate is 1 to 3 parts;

[0016] In some embodiments, the styrene monomer is selected from at least one of 3-chlorostyrene, styrene and p-chlorostyrene;

[0017] In some embodiments, the organosilicon monomer is selected from one of vinyl trichlorosilane, vinyl trimethoxysilane, vinyl triethoxysilane and vinyl triacetoxysilane;

[0018] In some embodiments, the raw material composition of the high bonding strength backing latex further includes 52 to 56 parts of water.

[0019] Another aspect of the present invention provides a method for preparing a high-bonding strength backing adhesive latex, comprising at least:

[0020] (1) mixing a soft monomer, a hard monomer, a protective monomer, a portion of water, a portion of an emulsifier, and a portion of an initiator, and pre-emulsifying the mixture to obtain an emulsified monomer;

[0021] (2) adding the remaining emulsifier and the remaining water into the reaction bottle and heating the temperature to 82-86° C., adding the remaining initiator to carry out a cracking reaction, and then taking 2.5-3.1% of the emulsified monomer and the organosilicon monomer into the reaction bottle, and then carrying out an initial reaction;

[0022] (3) After the above reaction is completed, the remaining emulsified monomer is added dropwise over 3.5 to 4 hours, and the reaction is then kept warm;

[0023] (4) Add the oxidant and the reductant to the materials in the reaction bottle, and after the oxidation-reduction system is heated and reacted, cool to below 45°C, and add a pH adjuster to adjust the pH value of the system to 7-9.

[0024] In step (1), the amount of the partial water is 30-35% of the total weight of the water;

[0025] In step (1), the amount of the partial emulsifier is 66-74% of the total weight of the emulsifier;

[0026] In step (1), the amount of the partial initiator is 48-52% of the total weight of the initiator;

[0027] In step (2), the cleavage reaction time is 3 to 4 minutes;

[0028] In step (2), the initial reaction time is 5 to 6 minutes;

[0029] In step (3), the temperature of the dropping is 82-86°C;

[0030] In step (3), the insulation reaction time is 1 to 1.5 hours;

[0031] In step (3), the temperature of the insulation reaction is 84-87° C.;

[0032] In step (4), the insulation reaction time is 0.5 to 1 h;

[0033] In step (4), the temperature of the insulation reaction is 72-76° C.;

[0034] In step (4), the cooling temperature is 30-40°C.

[0035] The mass ratio of the part of the emulsifier in step (1) to the remaining emulsifier in step (2) is 1:(0.2-0.6).

[0036] The third aspect of the present invention further provides a high-bonding strength back glue emulsion, which is prepared by the above-mentioned preparation method of the high-bonding strength back glue emulsion.

[0037] The fourth aspect of the present invention also provides an application of the above-mentioned high-bonding strength adhesive latex in the field of wall decoration.

[0038] The reagents and raw materials used in the present invention are commercially available.

[0039] The positive and progressive effects of the present invention are:

[0040] (1) The present invention adopts a seed polymerization process. The obtained backing latex uses pre-emulsified monomers as the seed emulsion structure. By introducing acrylic ester monomers in an optimal ratio, the particle size distribution and molecular weight of the later polymerization are effectively controlled. The remaining emulsified monomers are grafted and distributed on the chain ends of the seed emulsion shell.

[0041] (2) In addition to the seed synthesis design, the present invention also adds a silane monomer (organic silicone monomer) with a vinyl group at the seed synthesis end. The silane monomer with a vinyl group can undergo a coupling reaction with polar groups such as hydroxyl and carboxyl groups in acrylic molecules to form a covalent bond with high strength, thereby improving the later paint film strength of the back adhesive latex coating.

[0042] (3) The inventors found that the order of adding the organosilicon monomer has a great influence on the product performance of the high-bonding strength adhesive latex during the preparation of the high-bonding strength adhesive latex. First, the seed monomer in the reaction bottle system undergoes a polymerization reaction with the organosilicon-containing monomer. A small portion of the pre-emulsified monomer undergoes a preliminary seed emulsion polymerization in the emulsifier under the action of an initiator. When a sufficient number of silicon-containing latex particles with a small enough particle size are formed in the micelle, the monomer continues to polymerize with other large residual monomer raw materials. The molecular weight of the polymer continues to increase, and the corresponding polymer particles also gradually grow to form a silicon core-shell polymer dispersion. This order of adding materials can ensure that the organosilicon monomer fully undergoes a coupling reaction with the polar groups such as hydroxyl and carboxyl groups in the acrylic acid molecules, and the vinyl functional groups can be evenly distributed and grafted on the long-chain shell of the polymer. The reaction is stable, the particle size is moderate, and the strength after cross-linking can be improved.

[0043] (4) The preparation method of the high bonding strength backing glue latex provided by the present invention is easy to implement, the polymerization reaction rate is stable, the apparent particle size of the latex particles is moderate, and the amount of slag is low; through the process synthesis means, the coating property and bonding strength of the backing glue latex can be significantly enhanced.

[0044] (5) The backing adhesive latex provided by the present invention has excellent stability and can effectively fully coat the substrate. It also has high bonding performance. The bonding strength after immersion in water, heat aging, and freeze-thaw cycles exceeds the standard by more than 200%, and the actual use effect is excellent. DETAILED DESCRIPTION

[0045] The present invention is described in detail below in conjunction with the embodiments, and the technical scheme of the present invention is clearly and completely described to facilitate the understanding of the present invention by those skilled in the art. The described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. At the same time, the raw materials mentioned below that are not described in detail are all commercially available products; the process steps or preparation methods not mentioned in detail are process steps or preparation methods known to those skilled in the art.

[0046] Example 1

[0047] A high bonding strength backing adhesive latex, the raw material composition of which includes the following components in parts by weight, see Table 1;

[0048] Table 1 Weight parts of each component of raw materials

[0049]

[0050] Among them, the emulsification bottle system represents the material components added into the emulsification bottle, and the reaction bottle system represents the material components added into the reaction bottle.

[0051] The preparation method comprises the following steps:

[0052] (1) stirring and emulsifying 1.7 parts of sodium salt of alkyl alcohol monosulfosuccinate, 18 parts of water, 5 parts of styrene, 1 part of methyl methacrylate, 19 parts of n-butyl acrylate, 16 parts of isooctyl acrylate, 1 part of acrylic acid, 0.8 parts of acrylamide, and 0.09 parts of sodium persulfate to prepare an emulsified monomer;

[0053] (2) After adding the remaining emulsifier and water into the reaction bottle and heating to 82-86° C., the remaining initiator is added, and the cracking reaction is continued for 3 minutes. Then, 2.8% of the emulsified monomer and the organosilicon monomer are added into the reaction bottle and the reaction is continued for another 5 minutes;

[0054] (3) After the above reaction is completed, the remaining emulsified monomer is added dropwise over 225 min;

[0055] (4) After the emulsified monomer is added, keep the temperature at 84-87°C for 1.2 hours;

[0056] (5) Add the oxidant and the reductant to the materials in the reaction bottle, and then carry out the oxidation-reduction system, keep the temperature at 72-76°C for 0.5h, cool it to 40°C, and add a pH adjuster to adjust the pH value of the system to 7-9.

[0057] Example 2

[0058] A high bonding strength backing adhesive latex, the raw material composition of which includes the following components in parts by weight, see Table 2;

[0059] Table 2 Weight parts of each component of raw materials

[0060]

[0061]

[0062] The emulsification bottle system refers to the material components added into the emulsification bottle, and the reaction bottle system refers to the material components added into the reaction bottle.

[0063] The preparation method comprises the following steps:

[0064] (1) stirring and emulsifying 1.8 parts of sodium salt of alkyl alcohol monosulfosuccinate, 18 parts of water, 6 parts of styrene, 2 parts of methyl methacrylate, 18 parts of n-butyl acrylate, 15 parts of isooctyl acrylate, 1.1 parts of acrylic acid, 0.9 parts of acrylamide, and 0.1 parts of sodium persulfate to prepare an emulsified monomer;

[0065] (2) After adding the remaining emulsifier and water into the reaction bottle and heating to 82-86° C., the remaining initiator is added, and the cracking reaction is continued for 4 minutes. Then, 2.8% of the emulsified monomer and the organosilicon monomer are added into the reaction bottle and the reaction is continued for another 5.5 minutes.

[0066] (3) After the above reaction is completed, the remaining emulsified monomer is added dropwise over 240 minutes;

[0067] (4) After the emulsified monomer is added, keep the temperature at 84-87°C for 1.5 hours;

[0068] (5) Add the oxidant and the reductant to the materials in the reaction bottle, and then carry out the oxidation-reduction system, keep the temperature at 72-76°C for 0.7h, cool it to 35°C, and add a pH adjuster to adjust the pH value of the system to 7-9.

[0069] Example 3

[0070] A high bonding strength backing adhesive latex, the raw material composition of which includes the following components in parts by weight, see Table 3;

[0071] Table 3 Weight parts of each component of raw materials

[0072]

[0073]

[0074] The emulsification bottle system refers to the material components added into the emulsification bottle, and the reaction bottle system refers to the material components added into the reaction bottle.

[0075] The preparation method comprises the following steps:

[0076] (1) stirring and emulsifying 1.8 parts of sodium salt of alkyl alcohol monosulfosuccinate, 18 parts of water, 7 parts of styrene, 3 parts of methyl methacrylate, 17 parts of n-butyl acrylate, 14 parts of isooctyl acrylate, 1.2 parts of acrylic acid, 1.0 part of acrylamide, and 0.11 parts of sodium persulfate to prepare an emulsified monomer;

[0077] (2) After adding the remaining emulsifier and water into the reaction bottle and heating to 82-86° C., the remaining initiator is added, and the cracking reaction is continued for 3.5 minutes. Then, 2.8% of the emulsified monomer and the organosilicon monomer are added into the reaction bottle and the reaction is continued for another 6 minutes;

[0078] (3) After the above reaction is completed, the remaining emulsified monomer is added dropwise over 210 min;

[0079] (4) After the emulsified monomer is added, keep the temperature at 84-87°C for 1 hour;

[0080] (5) Add the oxidant and the reductant to the materials in the reaction bottle, and then carry out the oxidation-reduction system, keep the temperature at 72-76°C for 1 hour, cool it to 30°C, and add a pH adjuster to adjust the pH value of the system to 7-9.

[0081] The present invention also provides the following comparative examples.

[0082] Comparative Example 1

[0083] The only difference from Example 3 is that the amount of n-butyl acrylate used is 16 parts, and the amount of isooctyl acrylate used is 15 parts.

[0084] Comparative Example 2

[0085] The only difference from Example 3 is that the timing of adding vinyltrimethoxysilane is different, and it is added in step (1).

[0086] Comparative Example 3

[0087] The only difference from Example 3 is that the amount of n-butyl acrylate used is 31 parts, and isooctyl acrylate is not added.

[0088] Comparative Example 4

[0089] The only difference from Example 3 is that the amount of styrene used is 10 parts, and methyl methacrylate is not added.

[0090] Comparative Example 5

[0091] The only difference from Example 1 is that the amount of methyl methacrylate is 5 parts, the amount of styrene is 1 part, the amount of acrylic acid is 0.8 parts, and the amount of acrylamide is 1 part.

[0092] Comparative Example 6

[0093] Commercially available product, YS-8569 produced by Guangdong Yinyang Environmental Protection New Materials Co., Ltd.

[0094] Product performance testing

[0095] The emulsions of the embodiments and comparative examples were tested, and the test standards and methods were as follows:

[0096] 1. Emulsion stability: Tested according to GB / T 20623-2006 latex paint emulsion evaluation method.

[0097] 2. Bond strength test: Tested according to T / CBMF 87-2020.

[0098] The performance of the products of Examples 1 to 3 and Comparative Examples 1 to 6 of the present application was tested, and the results are shown in Table 4.

[0099] Table 4

[0100]

[0101] It can be seen from the above table that the comprehensive strength values ​​of Examples 1 to 3 are relatively excellent, and the comprehensive performance meets the evaluation requirements of GB / T 20623-2006 and T / CBMF 87-2020 standards at the same time; in the evaluation of the above items of Comparative Examples 1 to 5 and commercially available products, there are items that do not meet the standard requirements of Comparative Examples 2, Comparative Examples 4 and 5; Comparative Examples 1, Comparative Example 3 and Comparative Example 6 (commercially available products) can meet two standards, but the bonding strength is relatively low relative to the embodiments.

[0102] Finally, it should be noted that in the present invention, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements that are inherent to such process, method, article or apparatus.

[0103] Although the present disclosure has been disclosed above through the description of the specific embodiments of the present disclosure, it should be understood that those skilled in the art can design various modifications, improvements or equivalents to the present disclosure within the spirit and scope of the attached scheme. These modifications, improvements or equivalents should also be considered to be included in the scope of protection claimed by the present disclosure.

Claims

1. A raw material composition of a high bonding strength adhesive latex, characterized in that: It includes the following components in parts by weight: 6 to 10 parts of hard monomer, 31 to 35 parts of soft monomer, 1.8 to 2.2 parts of protective monomer, 0.08 to 0.12 parts of silicone monomer, 2.3 to 2.7 parts of emulsifier and 0.18 to 0.22 parts of initiator; The protective monomers include acrylamide and acrylic acid in a mass ratio of (0.6-1):

1.

2. The raw material composition of the high bonding strength backing adhesive latex according to claim 1, characterized in that: The mass ratio of the hard monomer to the soft monomer is 1:(3.1-5.9); and / or, the hard monomer comprises methyl methacrylate and styrene monomer; And / or, the soft monomer comprises n-butyl acrylate and isooctyl acrylate in a mass ratio of 1:(0.82-0.85); And / or, the organosilicon monomer is a silane monomer having a vinyl group; And / or, the emulsifier is selected from at least one of disodium ethoxylated fatty alcohol yellow succinate half ester, sodium salt of alkyl alcohol monosulfosuccinate, and disodium lauryl alcohol polyoxyethylene ether sulfosuccinate.

3. The raw material composition of the high bonding strength backing adhesive latex according to claim 1, characterized in that: The weight proportion of the methyl methacrylate is 1 to 3 parts; And / or, the styrene monomer is at least one selected from 3-chlorostyrene, styrene and p-chlorostyrene; And / or, the organosilicon monomer is selected from one of vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane and vinyltriacetoxysilane.

4. The raw material composition of the high bonding strength backing adhesive latex according to claim 1, characterized in that: The raw material composition of the high bonding strength backing latex further includes 52 to 56 parts of water.

5. A method for preparing a high-bonding strength adhesive latex, characterized in that: The raw material of the high-bonding strength backing adhesive latex comprises the raw material composition of the high-bonding strength backing adhesive latex according to any one of claims 1 to 4, and the method comprises the following steps: (1) mixing a soft monomer, a hard monomer, a protective monomer, a portion of water, a portion of an emulsifier, and a portion of an initiator, and pre-emulsifying the mixture to obtain an emulsified monomer; (2) adding the remaining emulsifier and the remaining water into the reaction bottle and heating the temperature to 82-86° C., adding the remaining initiator to carry out a cracking reaction, and then taking 2.5-3.1% of the emulsified monomer and the organosilicon monomer into the reaction bottle, and then carrying out an initial reaction; (3) After the above reaction is completed, the remaining emulsified monomer is added dropwise over 3.5 to 4 hours, and the reaction is then kept warm; (4) Add the oxidant and the reductant to the materials in the reaction bottle, and after the oxidation-reduction system is heated and reacted, cool down to below 45°C, and add a pH adjuster to adjust the pH value of the system to 7-9.

6. The method for preparing the high bonding strength backing adhesive latex according to claim 5, characterized in that: The preparation method satisfies at least one of the following conditions: In step (1), the amount of the partial water is 30-35% of the total weight of the water; In step (1), the amount of the partial emulsifier is 66-74% of the total weight of the emulsifier; In step (1), the amount of the partial initiator is 48-52% of the total weight of the initiator; In step (2), the cleavage reaction time is 3 to 4 minutes; In step (2), the initial reaction time is 5 to 6 minutes; In step (3), the temperature of the dropping is 82-86°C; In step (3), the insulation reaction time is 1 to 1.5 hours; In step (3), the temperature of the insulation reaction is 84-87° C.; In step (4), the insulation reaction time is 0.5 to 1 h; In step (4), the temperature of the insulation reaction is 72-76° C.; In step (4), the cooling temperature is 30-40°C.

7. The method for preparing the high bonding strength backing adhesive latex according to claim 3, characterized in that: The mass ratio of the part of the emulsifier in step (1) to the remaining emulsifier in step (2) is 1:(0.2-0.6).

8. A high bonding strength adhesive latex, characterized in that: The adhesive is prepared by the method for preparing the high-bonding-strength backing adhesive latex as claimed in any one of claims 5 to 7.

9. Use of the high bonding strength adhesive latex according to claim 8 in the field of wall decoration.

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