阅读说明：本技术 一种竹制工艺品用环保胶黏剂及其制备方法 (Environment-friendly adhesive for bamboo artware and preparation method thereof ) 是由 李明 李东猛 于 2021-10-21 设计创作，主要内容包括：本发明涉及一种竹制工艺品用环保胶黏剂及其制备方法,属于胶黏剂技术领域,该胶黏剂包括如下原料：改性淀粉、填料、聚乳酸、聚氨酯、蓖麻油、分散剂、抗氧剂；制备方法如下：将改性淀粉、聚乳酸、聚氨酯混合加热至180℃混合1h,然后加入蓖麻油、分散剂、抗氧剂、填料混合搅拌1-3h,并由双螺杆挤出机挤出,制得一种竹制工艺品用环保胶黏剂。本发明中通过对淀粉进行改性,提高竹制工艺品用环保胶黏剂的防水性能,提高竹制工艺品中胶黏剂的粘结强度,不同于传统木材加工工业用三大胶种,更加环保,满足生产、生活需要。(The invention relates to an environment-friendly adhesive for bamboo artware and a preparation method thereof, belonging to the technical field of adhesives, wherein the adhesive comprises the following raw materials: modified starch, filler, polylactic acid, polyurethane, castor oil, a dispersant and an antioxidant; the preparation method comprises the following steps: mixing and heating modified starch, polylactic acid and polyurethane to 180 ℃, mixing for 1h, then adding castor oil, a dispersing agent, an antioxidant and a filler, mixing and stirring for 1-3h, and extruding by a double-screw extruder to obtain the environment-friendly adhesive for the bamboo artware. According to the invention, the starch is modified, so that the waterproof performance of the environment-friendly adhesive for the bamboo artware is improved, the bonding strength of the adhesive in the bamboo artware is improved, the adhesive is different from three kinds of adhesives for the traditional wood processing industry, the environment is more protected, and the production and living needs are met.)

1. The environment-friendly adhesive for the bamboo artware comprises the following raw materials in parts by weight: 40-70 parts of modified starch, 0.5-0.8 part of filler, 15-20 parts of polylactic acid, 10-15 parts of polyurethane, 1-2 parts of castor oil, 0.5-1 part of dispersant and 1-2 parts of antioxidant; it is characterized in that the preparation method is characterized in that,

the modified starch is prepared by the following steps:

step one, drying starch for 24 hours at the temperature of 80 ℃, then adding ethyl acetate and pyridine, stirring for 20 minutes, adding stearic acid acyl chloride and acryloyl chloride, and reacting for 12 hours to obtain esterified starch;

and secondly, mixing the esterified starch with deionized water, stirring for 30min at the temperature of 90 ℃, then adding a polymerizable monomer, stirring for 10min, adding potassium persulfate, and reacting for 6h to obtain the modified starch.

2. The environment-friendly adhesive for bamboo artware as claimed in claim 1, wherein the dosage ratio of starch, ethyl acetate, pyridine, stearic acid acyl chloride and acryloyl chloride in the first step is 10 g: 50mL of: 2mL of: 4 g: 4g of the total weight of the mixture; in the second step, the dosage ratio of esterified starch, deionized water, polymerizable monomer and potassium persulfate is 5 g: 12mL of: 2 g: 0.2 g; the starch is one or more of corn starch, wheat starch and tapioca starch.

3. The environment-friendly adhesive for bamboo artware as claimed in claim 1, wherein the dispersant is oleic acid monoglyceride; the antioxidant is antioxidant 1010; the filler is nano silicon dioxide.

4. The environment-friendly adhesive for bamboo artware as claimed in claim 1, wherein the polymerizable monomer is prepared by the following steps:

step S11, mixing 4-hydroxy-3-methoxybenzaldehyde and absolute ethyl alcohol, then adding potassium carbonate and potassium iodide, stirring for 20min, then adding 3-bromopropylene, heating to 80 ℃, and carrying out reflux reaction for 6h to obtain a monomer a;

step S12, mixing the monomer a and phenol, then adding p-toluenesulfonic acid and zinc chloride, and stirring for 24 hours at the temperature of 40 ℃ to obtain a monomer b;

step S13, under the protection of nitrogen, mixing the monomer b and toluene, heating to 50 ℃, adding a Kanster catalyst, stirring for 40min, then adding tetramethyldisiloxane, heating to 70 ℃ after the addition, and stirring for reacting for 24h to obtain a monomer c;

step S14, mixing chlorinated trimellitic anhydride, pyridine, a monomer c and tetrahydrofuran at the temperature of 0 ℃, heating to 20 ℃, and stirring for reaction for 12 hours to obtain an intermediate c; and mixing the obtained intermediate c with glacial acetic acid, adding acrylamide, stirring for 1h at the temperature of 5 ℃, then heating to 120 ℃, and stirring for reacting for 8h to obtain the polymerizable monomer.

5. The environment-friendly adhesive for bamboo artware as claimed in claim 4, wherein the ratio of the amounts of 4-hydroxy-3-methoxybenzaldehyde, absolute ethyl alcohol, potassium carbonate, potassium iodide and 3-bromopropylene in step S11 is 0.1 mol: 60mL of: 0.2 mol: 0.2 mol: 0.2 mol;

in step S12, the dosage ratio of the monomer a, the phenol, the p-toluenesulfonic acid and the zinc chloride is 10 g: 9 g: 0.05mol:0.05 mol;

in step S13, the use ratio of the monomer b, toluene, Kansted catalyst and tetramethyldisiloxane is 6.6 g: 200mL of: 0.2 mL: 0.6 g;

in step S14, the use amount ratio of the chlorinated trimellitic anhydride to the pyridine to the monomer c to the tetrahydrofuran is 1 g: 0.35 g: 1 g: 50 mL; the dosage ratio of the intermediate c, the glacial acetic acid and the acrylamide is 0.8 g: 10mL of: 0.1 g.

6. The preparation method of the environment-friendly adhesive for bamboo artware according to claim 1, characterized by comprising the following steps:

mixing and heating modified starch, polylactic acid and polyurethane to 180 ℃, mixing for 1h, then adding castor oil, a dispersing agent, an antioxidant and a filler, mixing and stirring for 1-3h, and extruding by a double-screw extruder to obtain the environment-friendly adhesive for the bamboo artware.

Technical Field

The invention belongs to the technical field of adhesives, and particularly relates to an environment-friendly adhesive for bamboo artware and a preparation method thereof.

Background

The wood artware needs to use a certain amount of adhesive for plasticity in processing and preparation, and urea-formaldehyde resin is mostly adopted for gluing at present, so that the problem of indoor environment released by free formaldehyde is to be solved, and the pure urea-formaldehyde resin has great disadvantages in environmental protection and general gluing performance.

Three major glue species for wood processing industry are unified: urea-formaldehyde resin, phenol-formaldehyde resin and melamine formaldehyde resin have the problem of aldehyde toxic compound release in the preparation, curing and using processes, and seriously pollute the environment and harm the human health.

Disclosure of Invention

The invention aims to provide an environment-friendly adhesive for bamboo artware and a preparation method thereof.

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

the environment-friendly adhesive for the bamboo artware comprises the following raw materials in parts by weight:

40-70 parts of modified starch, 0.5-0.8 part of filler, 15-20 parts of polylactic acid, 10-15 parts of polyurethane, 1-2 parts of castor oil, 0.5-1 part of dispersant and 1-2 parts of antioxidant;

the modified starch is prepared by the following steps:

drying starch at 80 ℃ for 24h, adding ethyl acetate and pyridine, stirring for 20min, adding stearic acid acyl chloride and acryloyl chloride, reacting for 12h, washing with absolute ethyl alcohol after the reaction is finished, and drying in vacuum at 60 ℃ to constant weight to obtain esterified starch;

and secondly, mixing esterified starch with deionized water, stirring for 30min at the temperature of 90 ℃, then adding a polymerizable monomer, stirring for 10min, adding potassium persulfate, reacting for 6h, cooling to room temperature after the reaction is finished, washing with absolute ethyl alcohol, and drying to constant weight under the vacuum condition of 60 ℃ after the washing is finished to obtain the modified starch.

Further, in the first step, the dosage ratio of starch, ethyl acetate, pyridine, stearic acid acyl chloride and acryloyl chloride is 10 g: 50mL of: 2mL of: 4 g: 4g of the total weight of the mixture; in the second step, the dosage ratio of esterified starch, deionized water, polymerizable monomer and potassium persulfate is 5 g: 12mL of: 2 g: 0.2 g; the starch is one or more of corn starch, wheat starch and tapioca starch.

Further, the dispersant is oleic acid monoglyceride; the antioxidant is antioxidant 1010; the filler is nano silicon dioxide. The filler is added, so that the bonding strength of the adhesive is improved, and the stability of the adhesive is improved.

Further, the polymerizable monomer is prepared by the following steps:

step S11, mixing 4-hydroxy-3-methoxybenzaldehyde and absolute ethyl alcohol, then adding potassium carbonate and potassium iodide, stirring for 20min, then adding 3-bromopropylene, heating to 80 ℃, carrying out reflux reaction for 6h, cooling to room temperature after the reaction is finished, carrying out vacuum filtration, concentrating the obtained filtrate under reduced pressure, removing the solvent, then extracting with ethyl acetate and deionized water, and purifying the organic phase through a column to obtain a monomer a; wherein the dosage ratio of the 4-hydroxy-3-methoxybenzaldehyde to the absolute ethyl alcohol to the potassium carbonate to the potassium iodide to the 3-bromopropylene is 0.1 mol: 60mL of: 0.2 mol: 0.2 mol: 0.2 mol; hydroxyl in the 4-hydroxyl-3-methoxy benzaldehyde reacts with bromine of 3-bromopropylene to introduce double bonds;

step S12, mixing the monomer a and phenol, adding p-toluenesulfonic acid and zinc chloride, stirring for 24h at the temperature of 40 ℃, washing for 3 times by using hot water after the reaction is finished, dissolving the obtained crude product by using ethanol after the washing is finished, then precipitating by using deionized water, and drying the obtained precipitate to constant weight at 100 ℃ to obtain a monomer b; wherein the dosage ratio of the monomer a to the phenol to the p-toluenesulfonic acid to the zinc chloride is 10 g: 9 g: 0.05mol:0.05 mol; reacting phenol with aldehyde group in the monomer a, and introducing the phenol into the monomer a to obtain a monomer b containing phenolic hydroxyl;

step S13, under the protection of nitrogen, mixing the monomer b and toluene, heating to 50 ℃, adding a Kanster catalyst, stirring for 40min, then adding tetramethyldisiloxane, heating to 70 ℃ after the addition, stirring for reacting for 24h, after the reaction is finished, concentrating under reduced pressure, and removing the solvent to obtain a monomer c; wherein the dosage ratio of the monomer b, the toluene, the Kanst catalyst and the tetramethyldisiloxane is 6.6 g: 200mL of: 0.2 mL: 0.6 g; the double bond in the monomer b and the tetramethyl disiloxane are subjected to addition reaction to introduce siloxane bonds, so as to prepare a monomer c;

step S14, mixing chlorinated trimellitic anhydride, pyridine, a monomer c and tetrahydrofuran at the temperature of 0 ℃, heating to 20 ℃, stirring for reaction for 12 hours, and after the reaction is finished, carrying out reduced pressure concentration to remove the solvent to obtain an intermediate c; mixing the obtained intermediate c with glacial acetic acid, adding acrylamide, stirring for 1h at the temperature of 5 ℃, then heating to 120 ℃, and stirring for reacting for 8h to obtain a polymerizable monomer; wherein the dosage ratio of the chlorinated trimellitic anhydride to the pyridine to the monomer c to the tetrahydrofuran is 1 g: 0.35 g: 1 g: 50 mL; the dosage ratio of the intermediate c, the glacial acetic acid and the acrylamide is 0.8 g: 10mL of: 0.1 g; reacting phenolic hydroxyl in the monomer c with chlorinated trimellitic anhydride to obtain an intermediate c; the intermediate c is an anhydride compound, and the intermediate c reacts with acrylamide to introduce double bonds to obtain a polymerizable monomer.

A preparation method of an environment-friendly adhesive for bamboo artware comprises the following steps:

mixing and heating modified starch, polylactic acid and polyurethane to 180 ℃, mixing for 1h, then adding castor oil, a dispersing agent, an antioxidant and a filler, mixing and stirring for 1-3h, and extruding by a double-screw extruder to obtain the environment-friendly adhesive for the bamboo artware.

The invention has the beneficial effects that:

according to the invention, the starch is modified, so that the waterproof performance of the environment-friendly adhesive for the bamboo artware is improved, the bonding strength of the adhesive in the bamboo artware is improved, the adhesive is different from three kinds of adhesives for the traditional wood processing industry, the environment is more protected, and the production and living needs are met.

The modified starch is modified in a way that firstly, esterified starch is prepared, double bonds are introduced to the molecular structure of the starch, then, the esterified starch and polymerizable monomers are subjected to graft copolymerization, the polymerizable monomers are introduced into the structure of the starch, and the polymerizable monomers contain Si-0-Si structural networks, so that the water resistance of the adhesive is greatly improved; in addition, the structure of the polymerizable monomer contains an imide ring structure, so that the polymerizable monomer has excellent thermal stability and meets the production requirement.

Detailed Description

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

Example 1

Preparing a polymerizable monomer:

step S11, mixing 4-hydroxy-3-methoxybenzaldehyde and absolute ethyl alcohol, then adding potassium carbonate and potassium iodide, stirring for 20min, then adding 3-bromopropylene, heating to 80 ℃, carrying out reflux reaction for 6h, cooling to room temperature after the reaction is finished, carrying out vacuum filtration, concentrating the obtained filtrate under reduced pressure, removing the solvent, then extracting with ethyl acetate and deionized water, and purifying the organic phase through a column to obtain a monomer a; wherein the dosage ratio of the 4-hydroxy-3-methoxybenzaldehyde to the absolute ethyl alcohol to the potassium carbonate to the potassium iodide to the 3-bromopropylene is 0.1 mol: 60mL of: 0.2 mol: 0.2 mol: 0.2 mol;

step S12, mixing the monomer a and phenol, adding p-toluenesulfonic acid and zinc chloride, stirring for 24h at the temperature of 40 ℃, washing for 3 times by using hot water after the reaction is finished, dissolving the obtained crude product by using ethanol after the washing is finished, then precipitating by using deionized water, and drying the obtained precipitate to constant weight at 100 ℃ to obtain a monomer b; wherein the dosage ratio of the monomer a to the phenol to the p-toluenesulfonic acid to the zinc chloride is 10 g: 9 g: 0.05mol:0.05 mol;

step S13, under the protection of nitrogen, mixing the monomer b and toluene, heating to 50 ℃, adding a Kanster catalyst, stirring for 40min, then adding tetramethyldisiloxane, heating to 70 ℃ after the addition, stirring for reacting for 24h, after the reaction is finished, concentrating under reduced pressure, and removing the solvent to obtain a monomer c; wherein the dosage ratio of the monomer b, the toluene, the Kanst catalyst and the tetramethyldisiloxane is 6.6 g: 200mL of: 0.2 mL: 0.6 g;

step S14, mixing chlorinated trimellitic anhydride, pyridine, a monomer c and tetrahydrofuran at the temperature of 0 ℃, heating to 20 ℃, stirring for reaction for 12 hours, and after the reaction is finished, carrying out reduced pressure concentration to remove the solvent to obtain an intermediate c; mixing the obtained intermediate c with glacial acetic acid, adding acrylamide, stirring for 1h at the temperature of 5 ℃, then heating to 120 ℃, and stirring for reacting for 8h to obtain a polymerizable monomer; wherein the dosage ratio of the chlorinated trimellitic anhydride to the pyridine to the monomer c to the tetrahydrofuran is 1 g: 0.35 g: 1 g: 50 mL; the dosage ratio of the intermediate c, the glacial acetic acid and the acrylamide is 0.8 g: 10mL of: 0.1 g.

Example 2

Preparing modified starch:

drying starch at 80 ℃ for 24h, adding ethyl acetate and pyridine, stirring for 20min, adding stearic acid acyl chloride and acryloyl chloride, reacting for 12h, washing with absolute ethyl alcohol after the reaction is finished, and drying in vacuum at 60 ℃ to constant weight to obtain esterified starch;

and secondly, mixing esterified starch with deionized water, stirring for 30min at the temperature of 90 ℃, then adding a polymerizable monomer, stirring for 10min, adding potassium persulfate, reacting for 6h, cooling to room temperature after the reaction is finished, washing with absolute ethyl alcohol, and drying to constant weight under the vacuum condition of 60 ℃ after the washing is finished to obtain the modified starch.

Wherein, in the first step, the dosage ratio of starch, ethyl acetate, pyridine, stearic acid acyl chloride and acryloyl chloride is 10 g: 50mL of: 2mL of: 4 g: 4g of the total weight of the mixture; in the second step, the dosage ratio of esterified starch, deionized water, polymerizable monomer and potassium persulfate is 5 g: 12mL of: 2 g: 0.2 g; the starch is corn starch; the polymerizable monomers were prepared as in example 1.

Example 3

A preparation method of an environment-friendly adhesive for bamboo artware comprises the following steps:

mixing and heating modified starch, polylactic acid and polyurethane to 180 ℃, mixing for 1h, then adding castor oil, a dispersing agent, an antioxidant and a filler, mixing and stirring for 1h, and extruding by a double-screw extruder to obtain the environment-friendly adhesive for the bamboo artware.

Wherein the weight parts of the substances are as follows: 40 parts of modified starch, 0.5 part of filler, 15 parts of polylactic acid, 10 parts of polyurethane, 1 part of castor oil, 0.5 part of dispersant and 1 part of antioxidant; wherein the dispersant is oleic acid monoglyceride; the antioxidant is antioxidant 1010; the filler is nano silicon dioxide; modified starch was prepared as in example 2.

Example 4

A preparation method of an environment-friendly adhesive for bamboo artware comprises the following steps:

mixing and heating modified starch, polylactic acid and polyurethane to 180 ℃, mixing for 1h, then adding castor oil, a dispersing agent, an antioxidant and a filler, mixing and stirring for 2h, and extruding by a double-screw extruder to obtain the environment-friendly adhesive for the bamboo artware.

Wherein the weight parts of the substances are as follows: 50 parts of modified starch, 0.6 part of filler, 18 parts of polylactic acid, 12 parts of polyurethane, 1.5 parts of castor oil, 0.8 part of dispersant and 1.5 parts of antioxidant; wherein the dispersant is oleic acid monoglyceride; the antioxidant is antioxidant 1010; the filler is nano silicon dioxide; modified starch was prepared as in example 2.

Example 5

A preparation method of an environment-friendly adhesive for bamboo artware comprises the following steps:

mixing and heating modified starch, polylactic acid and polyurethane to 180 ℃, mixing for 1h, then adding castor oil, a dispersing agent, an antioxidant and a filler, mixing and stirring for 3h, and extruding by a double-screw extruder to obtain the environment-friendly adhesive for the bamboo artware.

Wherein the weight parts of the substances are as follows: 70 parts of modified starch, 0.8 part of filler, 20 parts of polylactic acid, 15 parts of polyurethane, 2 parts of castor oil, 1 part of dispersant and 2 parts of antioxidant; wherein the dispersant is oleic acid monoglyceride; the antioxidant is antioxidant 1010; the filler is nano silicon dioxide; modified starch was prepared as in example 2.

Comparative example 1

The starch from example 4 was replaced by the esterified starch from example 2, and the remaining raw materials and preparation were kept unchanged.

Comparative example 2

The modified starch of example 4 was replaced by corn starch, the remaining raw materials and the preparation process were kept unchanged.

The samples prepared in examples 3 to 5 and comparative examples 1 to 2 were subjected to the test;

the sample is coated by hand, and is brushed to 200g/m²Amount of sizingGluing the bamboo artware along one direction, placing the bamboo artware after leveling for 15 min, then carrying out hot pressing, wherein the hot pressing pressure of a pressing plate is 1.2MPa, the temperature is 120 ℃, the hot pressing time is 5min/mm, and then carrying out shearing and stretching at the speed of 10mm/min by using a universal tensile machine to obtain the bonding strength; placing the bamboo craft coated with the sample in water for soaking for 5 days, and then testing at a shearing rate of 10mm/min by adopting a universal tensile machine in a shearing mode to obtain wet adhesion strength;

the test results are shown in table 1 below:

TABLE 1

Sample (I)	Adhesive Strength (MPa)	Wet adhesion Strength (MPa)
			Example 3	5.2	3.5
Example 4	5.3	3.6
			Example 5	5.3	3.6
Comparative example 1	1.5	0.65
			Comparative example 2	1.1	0.42

As can be seen from table 1 above, the samples prepared according to the present invention have good adhesive strength and have good wet adhesive strength.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.