CN113502138A - Two-component aldehyde-free adhesive composition of water-based acrylic emulsion - Google Patents
Two-component aldehyde-free adhesive composition of water-based acrylic emulsion Download PDFInfo
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- CN113502138A CN113502138A CN202110893920.0A CN202110893920A CN113502138A CN 113502138 A CN113502138 A CN 113502138A CN 202110893920 A CN202110893920 A CN 202110893920A CN 113502138 A CN113502138 A CN 113502138A
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
- C09J133/04—Homopolymers or copolymers of esters
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J11/00—Features of adhesives not provided for in group C09J9/00, e.g. additives
- C09J11/08—Macromolecular additives
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2205/00—Polymer mixtures characterised by other features
- C08L2205/03—Polymer mixtures characterised by other features containing three or more polymers in a blend
- C08L2205/035—Polymer mixtures characterised by other features containing three or more polymers in a blend containing four or more polymers in a blend
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- Adhesives Or Adhesive Processes (AREA)
Abstract
The invention discloses a two-component formaldehyde-free adhesive composition of an aqueous acrylic emulsion, belonging to an aqueous formaldehyde-free adhesive composition product. The adhesive composition of the invention comprises: aqueous polymerized acrylic resin emulsion, polyvinyl alcohol, aromatic isocyanate crosslinking agent, filler and other auxiliary agents. The product does not contain formaldehyde, does not produce free formaldehyde, and has the advantages of good initial adhesion, longer working life, excellent bonding performance and the like.
Description
Technical Field
The invention relates to the technical field of fine chemical engineering, in particular to a two-component formaldehyde-free adhesive composition based on aqueous polymerization acrylic resin emulsion.
Background
Currently, artificial boards (plywood, fiberboard, shaving board, etc.) are produced by using triamine glue, namely urea formaldehyde resin, phenol formaldehyde resin and melamine formaldehyde resin. With the upgrading of wood processing industry and the increasing demand of the consumer market for formaldehyde-free and environment-friendly home decoration materials, the artificial board industry has begun to turn to the use of formaldehyde-free and environment-friendly adhesives.
The main competitive products in the market at present have 2 categories.
Class 1 is formaldehyde-based "trialdehyde glues" (mostly phenolic, urea-formaldehyde, melamine-formaldehyde glues). The existing defects are as follows: non-aqueous products, glue itself, during production and final products can release harmful gases such as free formaldehyde, phenol and other VOCs.
The 2 nd category is non-formaldehyde glue (mainly polyurethane and soybean protein glue). The polyurethane adhesives have the following disadvantages: the glue has short working life and is greatly influenced by the temperature and the humidity of the environment.
The artificial board product made of the soybean protein glue is easy to mildew, the weather resistance of the glue is not as stable as that of chemical glue, the viscosity of the glue is high, and the production efficiency is low.
At present, market environment and national policies promote the development of the artificial board industry towards aldehyde-free, green production, environment-friendly and sustainable development.
However, the common disadvantages of formaldehyde-free adhesives are as follows:
the pot life of the adhesive is short. Most of two-component adhesives added with curing agents or crosslinking agents have active reaction performance and high crosslinking reaction speed, so that the mixed adhesives need to be used as soon as possible in a short time, otherwise, the adhesives can lose effectiveness after self-curing or self-crosslinking. Thus, higher requirements are put on the operation process conditions of actual production and the operation specifications of operators.
② the mechanical strength of the gluing is not as good as that of the glue containing aldehyde. Some aldehyde-free adhesives use high molecular weight polymers or aqueous emulsions. These high molecular polymers or aqueous emulsions have a relatively low glass transition temperature, which results in insufficient heat resistance, weather resistance and mechanical strength of the glue. The I-type artificial board specified by the national standard needs to be boiled in boiling water at 100 ℃ for 4 hours and dried for 20 hours without glue failure. Therefore, these low glass transition temperature adhesives fail the test.
Thirdly, the protein aldehyde-free adhesive has insufficient water resistance and is easy to breed mildew and bacteria. Adhesives based on starch and soy protein are easily corroded and damaged by microorganisms in the natural environment due to a large amount of natural organic matters, and have the problems of mildew, adhesive degradation failure and the like.
Disclosure of Invention
The invention aims to invent a two-component formaldehyde-free adhesive composition based on aqueous polymerized acrylic resin emulsion, which is used for producing artificial boards (multilayer solid wood composite plywood, fiber boards, shaving boards and the like, including but not limited to) so as to obtain artificial board products without free formaldehyde emission.
The technical scheme is as follows: the product belongs to a waterborne formaldehyde-free adhesive composition product. The product is based on water-based polymerized acrylic resin emulsion, polyvinyl alcohol, aromatic isocyanate crosslinking agent, filler and other assistants.
The concrete raw materials and compositions are as follows:
aqueous polymerized acrylic resin emulsion. Wherein the aqueous polymerized acrylic resin emulsion has at least one structural unit having at least one functional group including carboxyl, aliphatic amine, aromatic amine, hydroxylamine, amide, etc.
The aqueous polymeric acrylic resin emulsion is prepared by polymerization of a plurality of acrylic monomers and shearing. Among these, acrylic monomers include, but are not limited to, methyl methacrylate, ethyl methacrylate, styrene, acrylonitrile, 2-hydroxyethyl enoate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, glycidyl methacrylate, acrylamide, N-methylolacrylamide, N-butoxymethyl (meth) acrylamide, diacetone acrylamide (DAAM), ethyl acetoacetate methacrylate (AAEM), divinylbenzene, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, gamma-methacryloxypropyltrimethoxysilane, and the like, and combinations thereof.
The average molecular weight of the aqueous polymerized acrylic resin is from 10000 to 100000, and the preferable range is 30000 to 80000
The glass transition temperature of the aqueous polymeric acrylic resin is in the range of-10 to 50 deg.C, preferably in the range of 25 to 45 deg.C. High glass transition temperatures can provide excellent adhesive bonding and mechanical properties.
In the waterborne formaldehyde-free adhesive composition, the waterborne polymerized acrylic resin emulsion accounts for 10 to 80 percent of the solid mass, and the preferred range is from 30 to 60 percent.
② polyvinyl alcohols. The polyvinyl alcohol can provide excellent film forming property and adhesion, the mechanical property of the film is excellent, and the tensile strength of the film is enhanced along with the increase of polymerization degree and alcoholysis degree. The water-based acrylic resin emulsion can be used as a plasticizer to help the water-based acrylic resin emulsion to form a film at normal temperature and provide sufficient initial adhesion so as to adhere and shape the artificial board after cold pressing, and the artificial board is not dispersed or separated during the transportation and the subsequent hot press forming.
The polyvinyl alcohol has a degree of hydrolysis ranging from 78% to 99%, preferably ranging from 88% to 99%.
The degree of polymerization of the polyvinyl alcohol ranges from 600 to 2500, preferably from 1700 to 2500.
In the aqueous formaldehyde-free adhesive composition, the polyvinyl alcohol accounts for 5 to 50 percent of the solid mass, and the preferable range is from 10 to 30 percent.
③ aromatic isocyanate cross-linking agent. The aromatic isocyanate crosslinking agent refers to diisocyanate containing benzene rings in the molecular structure, and includes but is not limited to Toluene Diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymeric MDI and other special aromatic isocyanates.
In the waterborne formaldehyde-free adhesive composition, the aromatic isocyanate crosslinking agent accounts for 3-15% of the solid mass, and the preferable range is 5-10%.
Fillers and other auxiliary agents. Other fillers include, but are not limited to, calcium carbonate, silica fume, flour, bentonite, and the like, and mixtures thereof. Calcium carbonate is preferred. In the waterborne formaldehyde-free adhesive composition, the filler accounts for 0 to 70 percent of the solid mass, and the preferable range is from 30 to 50 percent.
Other adjuvants include, but are not limited to: defoaming agents (silicones, mineral oils, alcohols, accounting for from 0.1 to 0.2% by mass of solids), dispersants (polymers, inorganic phosphates, etc., accounting for from 0.1 to 0.2% by mass of solids), thickeners (celluloses, alkali swelling thickeners, associative thickeners, accounting for from 1 to 3% by mass of solids), film forming aids (such as alcohol esters (lauryl alcohol esters, etc.), alcohol ethers (ethylene glycol butyl ether, diethylene glycol butyl ether, propylene glycol phenyl ether, etc.)), bactericides, leveling agents, wetting agents, plasticizers, etc.
Has the advantages that: in order to obtain better mechanical properties of the glue, the present patent uses an aqueous polymeric acrylic resin emulsion with a high glass transition temperature, as distinguished from the low glass transition temperature emulsions used in the other solutions. In addition, the initial adhesion and the holding power of the adhesive are improved by simultaneously using the polyvinyl alcohol and the aromatic polyurethane crosslinking agent so as to meet the process and performance requirements of the artificial board industry. Meanwhile, aromatic polyurethane is used in the glue composition scheme in the patent. The pot life of the glue using the curing agent is short, so that a small amount of glue needs to be prepared for many times by workers in the actual production process, and the actual production efficiency is not facilitated. However, the pot life of the glue composition can be prolonged to at least 4 hours, so that the service life of the glue is greatly prolonged, and the large-scale practical production is facilitated.
This patent the air contaminant such as formaldehyde and phenol is not contained to product itself, and suitability and veneer mechanical properties are good, can not reduce current production efficiency, need not to change current production facility, and no free formaldehyde release in the production process belongs to the theory that aqueous gluing agent system accords with green production.
Detailed Description
The following examples illustrate the invention in more detail, but the scope of the invention is not limited to the examples.
Examples comparison of aqueous acrylic emulsions of one, different glass transition temperatures
EXAMPLE sample preparation
Description of the drawings: the materials in the examples in the above table were sequentially charged in the order from top to bottom, and were stirred and charged by using a high-speed dispersion mixer at a speed of 800-. Stirring for at least 40min until the viscosity state of the adhesive is stable and no large particles or agglomeration exist.
Other embodiments below all use this approach and are not repeated in the following.
② preparation of multilayer solid wood composite plywood test piece and test result of bonding performance
Description of the drawings:
a. the adhesives in different embodiments are respectively coated on the front and back surfaces of a eucalyptus veneer with the thickness of 2.2mm, and the coating amount is controlled to be 180-200g/m2Within the range of (1). Then 7 layers of eucalyptus veneers are paved and stacked in the wood grain direction which is staggered horizontally and vertically. At a rate of 8-10kg/cm2The unit pressure of (1) cold pressing and compacting 7 layers of eucalyptus veneers, and taking out after 30 min. Finally 8-10kg/cm2Hot-press compacting 7 layers of eucalyptus veneers at 120 ℃ for 16min (heating in unit time of sheet thickness mm 1 min). And finishing the preparation of the multilayer solid wood composite plywood.
b. The dipping stripping passing rate is tested according to the requirements of I type plates in the national standard GB17657-2013 physicochemical property test method for artificial boards and veneer artificial boards. (the tea is immersed in boiling water for 4h, then dried at 63 ℃ for 20h, immersed in boiling water for 4h, and finally dried at 63 ℃ for 3 h). In addition, the wet bond strength of the test pieces after impregnation was tested according to the standard.
The other embodiments below all adopt the above-described manner, and are not repeated in the following.
The test results in the table above show that:
under the same preparation process, the water-based acrylic emulsion with different glass transition temperatures has great influence on the gluing performance of the finished plywood. Using a lower TgThe test piece of the emulsion adhesive of (1), the dipping peeling passage rate and the humidityThe bonding strength is obviously lower than the high TgThe emulsion adhesive of (1). The glass transition temperature has a great influence on the performance strength of the adhesive.
Two, comparison of examples with different amounts of polyvinyl alcohol
EXAMPLE sample preparation
② preparation of multilayer solid wood composite plywood test piece and test results of bonding performance and initial adhesion
The test results in the table above show that:
the use amount of the polyvinyl alcohol has great influence on the gluing performance of the finished plywood product under the same preparation process. The test piece without polyvinyl alcohol is not shaped, and the cold-pressed plywood test piece cannot be fed into the hot pressing plate gap of the hot press layer by layer in the actual production process. Along with the increase of the dosage of the polyvinyl alcohol, the cold-press forming effect of the plywood test piece is gradually improved. Meanwhile, the dipping and peeling passing rate and the wet bonding strength of the test piece are also obviously improved. The polyvinyl alcohol is added into the adhesive, so that the production process parameters of the plywood and the performance of the adhesive can be exerted.
Examples comparison of three, different amounts of aromatic isocyanate crosslinker
EXAMPLE sample preparation
② preparation of multilayer solid wood composite plywood test piece and test result of bonding performance
The test results in the table above show that:
under the same preparation process, the dosage of the isocyanate crosslinking agent has obvious influence on the bonding performance of the finished plywood. The impregnation peel passage rate and the wet bond strength of the test pieces gradually increased with the increase of the crosslinking agent. The addition of the cross-linking agent is beneficial to improving the bonding performance of the adhesive.
Testing result of long service life of adhesive and test piece bonding performance variation trend
The test results in the table above show that:
on the premise of the same example 9, the impregnation peeling rate and the wet bond strength of the test piece slightly decreased with the extension of the adhesive standing time. However, the test result after the standing time reaches 5 hours can still meet the requirements of national standards. In addition, after the standing time is prolonged to 5 hours, the viscosity of the adhesive is slightly increased, the fluidity of the adhesive is slightly reduced, but the adhesive can also meet the requirements of actual production, and the adhesive can freely flow down without wall hanging or caking. Compared with the defect that the traditional formaldehyde-free isocyanate adhesive has a short use window period, the composition scheme disclosed by the patent has a longer application life, can better meet the process requirements of actual production, and reduces the adhesive preparation frequency of workers.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application.
Claims (10)
1. The two-component formaldehyde-free adhesive composition of the water-based acrylic emulsion is characterized by comprising the following components in parts by weight: aqueous polymerized acrylic resin emulsion, polyvinyl alcohol, aromatic isocyanate crosslinking agent, filler and other auxiliary agents.
2. The two-part aldehyde-free adhesive composition of claim 1, wherein the aqueous polymeric acrylic resin emulsion comprises at least one structural unit having at least one functional group selected from the group consisting of carboxyl, aliphatic amine, aromatic amine, hydroxylamine, amide, and the like.
3. The two-part aldehyde-free adhesive composition of claim 1, wherein the aqueous polymeric acrylic resin has an average molecular weight of 10000 to 100000 and a glass transition temperature of-10 to 50 ℃.
4. The two-part aldehyde-free adhesive composition according to claim 1, wherein the aqueous polymerized acrylic resin emulsion accounts for 10 to 80 percent of the solid mass.
5. The two-part aldehyde-free adhesive composition of claim 1, wherein the polyvinyl alcohol has a degree of hydrolysis ranging from 78% to 99% and a degree of polymerization ranging from 600 to 2500.
6. The two-part aldehyde-free adhesive composition according to claim 1, wherein the polyvinyl alcohol is present in an amount of from 5 to 50% by mass based on the solid.
7. The two-part aldehyde-free adhesive composition of claim 1, wherein the aromatic isocyanate crosslinking agent is a diisocyanate having a molecular structure containing benzene rings, and comprises toluene diisocyanate, diphenylmethane diisocyanate, and polymeric MDI.
8. The two-part aldehyde-free adhesive composition according to claim 1, wherein the aromatic isocyanate crosslinking agent is present in an amount of from 3 to 15% by mass based on the solid.
9. The two-part aldehyde-free adhesive composition of claim 1, wherein the filler is one or more of calcium carbonate, silica powder, flour, and bentonite.
10. The two-part aldehyde-free adhesive composition of claim 1, wherein the auxiliary agent is: one or more of defoaming agent, dispersing agent, thickening agent, film forming auxiliary agent, bactericide, smoothing agent, wetting agent and plasticizer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110893920.0A CN113502138A (en) | 2021-08-05 | 2021-08-05 | Two-component aldehyde-free adhesive composition of water-based acrylic emulsion |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110893920.0A CN113502138A (en) | 2021-08-05 | 2021-08-05 | Two-component aldehyde-free adhesive composition of water-based acrylic emulsion |
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| CN113502138A true CN113502138A (en) | 2021-10-15 |
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| CN202110893920.0A Pending CN113502138A (en) | 2021-08-05 | 2021-08-05 | Two-component aldehyde-free adhesive composition of water-based acrylic emulsion |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114211575A (en) * | 2021-12-24 | 2022-03-22 | 江苏艾科赛特新材料有限公司 | Formaldehyde-free composite furniture board and preparation method thereof |
| CN114227832A (en) * | 2021-12-27 | 2022-03-25 | 江苏艾科赛特新材料有限公司 | Treatment method for preparing plywood by using single board containing burr groove marks |
| CN115537151A (en) * | 2022-10-14 | 2022-12-30 | 沈阳爱克浩博化工有限公司 | High-strength water-resistant EPI (expanded polyethylene) plate splicing adhesive suitable for humid environment and preparation method thereof |
| CN115782324A (en) * | 2022-11-29 | 2023-03-14 | 江苏艾科赛特新材料有限公司 | Formaldehyde-free artificial leather composite artificial board and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005200524A (en) * | 2004-01-15 | 2005-07-28 | Saiden Chemical Industry Co Ltd | Water-based adhesive composition for wood working |
| JP2009203368A (en) * | 2008-02-28 | 2009-09-10 | Showa Highpolymer Co Ltd | Adhesive composition for wood |
| JP2012211261A (en) * | 2011-03-31 | 2012-11-01 | Aica Kogyo Co Ltd | Adhesive composition |
-
2021
- 2021-08-05 CN CN202110893920.0A patent/CN113502138A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005200524A (en) * | 2004-01-15 | 2005-07-28 | Saiden Chemical Industry Co Ltd | Water-based adhesive composition for wood working |
| JP2009203368A (en) * | 2008-02-28 | 2009-09-10 | Showa Highpolymer Co Ltd | Adhesive composition for wood |
| JP2012211261A (en) * | 2011-03-31 | 2012-11-01 | Aica Kogyo Co Ltd | Adhesive composition |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114211575A (en) * | 2021-12-24 | 2022-03-22 | 江苏艾科赛特新材料有限公司 | Formaldehyde-free composite furniture board and preparation method thereof |
| CN114227832A (en) * | 2021-12-27 | 2022-03-25 | 江苏艾科赛特新材料有限公司 | Treatment method for preparing plywood by using single board containing burr groove marks |
| CN115537151A (en) * | 2022-10-14 | 2022-12-30 | 沈阳爱克浩博化工有限公司 | High-strength water-resistant EPI (expanded polyethylene) plate splicing adhesive suitable for humid environment and preparation method thereof |
| CN115782324A (en) * | 2022-11-29 | 2023-03-14 | 江苏艾科赛特新材料有限公司 | Formaldehyde-free artificial leather composite artificial board and preparation method thereof |
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