A long-activation-period hydroxypropyl emulsion for plywood glue and its preparation method and application

Abstract

The present invention relates to the technical field of hydroxypropyl emulsions, and discloses a long-activation-period hydroxypropyl emulsion for plywood glue and its preparation method and application. The present invention adopts a two-step polymerization and post-dispersion method, first polymerizing methyl methacrylate, butyl acrylate, and styrene to prepare a hydrophobic inner core layer, then adding hydroxyethyl methacrylate, acrylic acid, sulfonate-modified epoxy resin, and adamantane-modified phosphate-modified phenolic resin to continue polymerization, preparing a hydrophilic outer shell layer, adding dimethylethanolamine to neutralize the carboxyl groups in the outer shell layer and adding water to disperse, to obtain a long-activation-period hydroxypropyl emulsion for plywood glue. The long side chain groups in the hydrophilic outer shell are hydrophobic, and when adding water to disperse, they can increase the interaction with the inner core molecular chain to form a tighter core-shell structure. The certain steric hindrance of the long side chain groups can wrap around a part of the hydroxyl groups, thereby avoiding the premature reaction of the hydroxypropyl emulsion with the curing agent, extending the activation period, and having a good high temperature resistance effect.

Description

Technical Field

[0001] The invention relates to the technical field of hydroxypropylene emulsions, in particular to a hydroxypropylene emulsion with a long activation period for plywood glue, and a preparation method and application thereof. Background Art

[0002] Panel glue refers to an adhesive used to join wood products such as laminated timber. Currently, most adhesives used in this area in China are two-component panel glues consisting of a base and a curing agent, with the curing agent typically being an isocyanate. Hydroxypropylene glycol emulsion is a hydroxyl-functional acrylic emulsion formed by the polymerization of hydroxyl acrylic monomers with acrylic or vinyl monomers. Two-component panel glues with hydroxypropylene glycol emulsion as the base and isocyanate as the curing agent require separate packaging before use. The two components are then mixed to initiate a chemical reaction, which causes a continuous increase in viscosity before eventually gelling. During this period, the glue maintains a certain level of fluidity and adhesive properties, known as its activation period. During this activation period, the adhesive exhibits optimal adhesive properties, making it suitable for bonding operations. However, many two-component panel glues suffer from a short activation period, which hinders their application. Furthermore, due to the insufficient crosslinking density of hydroxypropylene glycol emulsions, their high-temperature resistance is less than ideal. Therefore, addressing the short activation period of hydroxypropylene glycol emulsions after contact with isocyanates and improving their high-temperature resistance are of great significance. In the document "Development of Two-Component Paneling Glue", a two-component paneling glue was synthesized using water-based polymer emulsion as the main agent and isocyanate as the curing agent. Its characteristics are room temperature curing, high bonding strength, water resistance, heat resistance, aging resistance and other properties, but its activation period needs to be improved. Summary of the Invention

[0003] (1) Technical problems solved

[0004] In response to the shortcomings of the existing technology, the present invention provides a hydroxypropyl emulsion with a long activation period for plywood glue, and its preparation method and application. The plywood glue synthesized by using the hydroxypropyl emulsion prepared by the present invention as the main agent and toluene diisocyanate as the curing agent has a longer activation period and better high temperature resistance.

[0005] (2) Technical solution

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a long-activation-period hydroxypropyl emulsion for plywood glue, comprising the following components by weight: 18-22 parts by weight of methyl methacrylate, 7-10 parts by weight of butyl acrylate, 4-6 parts by weight of styrene, 16-20 parts by weight of hydroxyethyl methacrylate, 10-18 parts by weight of acrylic acid, 3-6 parts by weight of sulfonate-modified epoxy resin, and 2-5 parts by weight of adamantane-modified phosphate-modified phenolic resin.

[0007] Preferably, the preparation method of the sulfonate-modified epoxy resin comprises the following steps:

[0008] (1) Add 8-12 g of 1-naphthol-5-sulfonic acid and 15-20 g of phosphorus oxychloride to a single-necked flask, heat and reflux for 7-8 h, then remove the remaining phosphorus oxychloride under reduced pressure, add 0.05-0.07 g of triethylamine catalyst dropwise at 0-5 ° C, and then add 8-10 g of 3-butene-1-ol, react at 25-28 ° C for 10-12 h, filter and distill under reduced pressure to obtain intermediate 1;

[0009] (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 90-98°C to form a homogeneous phase, add ethyltriphenylphosphonium bromide catalyst, heat to 150-160°C at a rate of 2-4°C / min, and react for 50-70 minutes. After the reaction is completed, cool, wash and dry to obtain a sulfonate-modified epoxy resin.

[0010] Preferably, the temperature of the reflux reaction in step (1) is 72-80°C.

[0011] Preferably, in step (2), the mass ratio of the intermediate 1, bisphenol A epoxy resin, and ethyltriphenylphosphonium bromide is 1:3.4-3.6:0.04-0.08.

[0012] Preferably, the preparation method of the adamantane-modified phosphate-modified phenolic resin comprises the following steps:

[0013] S1. To tetrahydrofuran solvent were added 15-18 g of 3-hydroxy-1-adamantyl methacrylate, 7-9 g of ethylene (chloromethyl) dimethoxysilane, 0.03-0.06 g of potassium hydroxide catalyst, and 0.05-0.07 g of 4-methoxyphenol polymerization inhibitor, stirred and mixed, and reacted for 2-2.5 h. After the reaction, the mixture was filtered, washed, and dried to obtain intermediate 2;

[0014] S2. 10-14 g of phenol, 22-30 g of formaldehyde solution, 0.08-0.1 g of oxalic acid catalyst were added to deionized water, stirred and mixed, and reacted at 88-92 ° C for 3-4 h, and then 1.5-2 g of 2-amino-5-methylphenyl phosphoric acid was added thereto. The reaction was continued for 1.5-2 h. After the reaction was completed, deionized water was added, washed with water for 40-50 min, and then allowed to stand for 20-24 h. After separation, the upper layer of water was poured out to obtain an amino-modified phosphate-modified phenolic resin;

[0015] S3. Add 7-9 g of amino-modified phosphate-modified phenolic resin, 12-14 g of intermediate 2, and 0.02-0.05 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 30-35°C for 2-4 hours. After the reaction is completed, filter, wash and dry to obtain adamantane-modified phosphate-modified phenolic resin.

[0016] Preferably, the reaction temperature in S1 is 40-48°C.

[0017] Preferably, the mass fraction of the formaldehyde aqueous solution in S2 is 36%-38%.

[0018] Preferably, the method for preparing the long-activation-period hydroxypropyl emulsion for the puzzle glue comprises the following steps:

[0019] Step 1: Add ethylene glycol butyl ether solvent to the reactor, heat to 110-120 ° C, mix 18-22 parts by weight of methyl methacrylate, 7-10 parts by weight of butyl acrylate, 4-6 parts by weight of styrene, 0.2-0.6 parts by weight of benzoyl peroxide initiator, and 0.1-0.3 parts by weight of dodecyl mercaptan chain transfer agent, and add the mixture dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled to be 2.5-3 hours. After the addition is completed, keep the mixture warm for 50-70 minutes.

[0020] Step 2: Mix 16-20 parts by weight of hydroxyethyl methacrylate, 10-18 parts by weight of acrylic acid, 3-6 parts by weight of sulfonate-modified epoxy resin, 2-5 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.3-0.8 parts by weight of benzoyl peroxide initiator, and 0.2-0.4 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the reaction solution of step 1. The addition time is controlled at 1-1.5 hours. After the addition is completed, keep warm and react for 1.5-2 hours. After the reaction is completed, evaporate the solvent, add 0.3-0.6 parts by weight of dimethylethanolamine neutralizer and stir for 15-20 minutes, add deionized water to disperse, and obtain a hydroxypropyl emulsion with a long activation period for puzzle glue.

[0021] (3) Beneficial technical effects

[0022] The present invention prepares a long-active-life hydroxypropylene emulsion for panel glue having a core-shell structure through a two-step polymerization and post-dispersion method. Methyl methacrylate, butyl acrylate, and styrene are first polymerized to prepare a hydrophobic inner core layer. Hydroxyethyl methacrylate, acrylic acid, a sulfonate-modified epoxy resin, and an adamantane-modified phosphate-modified phenolic resin are then added and further polymerized to prepare a hydrophilic outer shell layer. Dimethylethanolamine is then added to neutralize the carboxyl groups in the hydrophilic outer shell layer, and the mixture is dispersed in water to obtain the long-active-life hydroxypropylene emulsion for panel glue.

[0023] The sulfonic acid group in 1-naphthol-5-sulfonic acid reacts with phosphorus oxychloride to undergo an acyl chloride reaction, which then reacts with the hydroxyl group in 3-butene-1-ol to introduce a sulfonate group, yielding Intermediate 1. The phenolic hydroxyl group in Intermediate 1 reacts with the epoxy group in bisphenol A epoxy resin to yield a sulfonate-modified epoxy resin. The hydroxyl group in 3-hydroxy-1-adamantyl methacrylate undergoes a substitution reaction with the chlorine group in ethylene (chloromethyl)dimethoxysilane to yield Intermediate 2. Phenol and formaldehyde undergo a condensation reaction to yield a phenolic resin. The phenolic hydroxyl group in the phenolic resin reacts with the phosphate group in 2-amino-5-methylphenylphosphoric acid to yield an amino-modified phosphate-modified phenolic resin. The amino group in the amino-modified phosphate-modified phenolic resin undergoes a Michael addition reaction with Intermediate 2 to yield an adamantane-modified phosphate-modified phenolic resin.

[0024] In sulfonate-modified epoxy resins, the sulfur and oxygen atoms in the sulfonate group have high bond energy, resulting in high thermal stability and improving the high-temperature resistance of hydroxypropylene emulsions. The naphthyl group, formed by the fusion of two benzene rings, has a highly stable conjugated system, exhibiting high thermal stability and enhancing the high-temperature resistance of hydroxypropylene emulsions. The epoxy resin forms a dense cross-linked network during the curing process, further improving the high-temperature resistance of the hydroxypropylene emulsion. In adamantane-modified phosphate-modified phenolic resin, the highly symmetrical and rigid structure of adamantane has extremely high thermal stability, enhancing the high-temperature resistance of the hydroxypropylene emulsion. The phenolic resin molecule contains a large number of benzene rings and methylene groups. These structural units have high bond energies, enabling the phenolic resin to maintain good stability at high temperatures, thereby enhancing the high-temperature resistance of the hydroxypropylene emulsion. The POC bond formed by the reaction of 2-amino-5-methylphenylphosphonic acid and phenolic resin blocks the phenolic hydroxyl groups in the phenolic resin, reducing the resin's oxidative sensitivity at high temperatures and increasing the benzene ring content in the resin, thereby improving the thermal stability of the phenolic resin and enhancing the high-temperature resistance of the hydroxypropylene emulsion.

[0025] In the core-shell structured hydroxypropyl emulsion, the core is completely obtained by polymerization of hydrophobic monomers, and the hydrophilic units are concentrated in the outer shell. The long side chain groups in the hydrophilic shell are hydrophobic. When dispersed with water, they can increase the interaction between the outer shell and the inner core molecular chains, entangle and curl up with each other to form a tighter core-shell structure. The certain steric hindrance of the long side chain groups can wrap around part of the hydroxyl groups, preventing the hydroxypropyl emulsion from reacting with the curing agent too early, thereby prolonging the activation period. DETAILED DESCRIPTION Example 1

[0026] (1) Add 8 g of 1-naphthol-5-sulfonic acid and 15 g of phosphorus oxychloride to a single-necked flask, heat to 72°C, reflux for 7 h, and then remove the remaining phosphorus oxychloride under reduced pressure. Add 0.05 g of triethylamine catalyst dropwise at 0°C. After the addition is complete, add 8 g of 3-butene-1-ol and react at 25°C for 10 h. After the reaction is complete, filter and distill under reduced pressure to obtain intermediate 1.

[0027] (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 90°C to form a homogeneous phase, add ethyl triphenyl phosphonium bromide catalyst, wherein the mass ratio of intermediate 1, bisphenol A epoxy resin and ethyl triphenyl phosphonium bromide is 1:3.4:0.04, heat to 150°C at a rate of 2°C / min, react for 50 minutes, cool after the reaction, wash and dry to obtain sulfonate modified epoxy resin;

[0028] (3) Add 15 g of 3-hydroxy-1-adamantyl methacrylate, 7 g of ethylene (chloromethyl) dimethoxysilane, 0.03 g of potassium hydroxide catalyst, and 0.05 g of 4-methoxyphenol polymerization inhibitor to tetrahydrofuran solvent, stir and mix, and react at 40°C for 2 h. After the reaction is completed, filter, wash and dry to obtain intermediate 2;

[0029] (4) Add 10 g of phenol, 22 g of formaldehyde aqueous solution, and 0.08 g of oxalic acid catalyst to deionized water, wherein the mass fraction of the formaldehyde aqueous solution is 36%, stir and mix, react at 88 ° C for 3 h, add 1.5 g of 2-amino-5-methylphenylphosphoric acid, and continue to react for 1.5 h. After the reaction is completed, add deionized water, wash with water for 40 min, and then let it stand for 20 h. After stratification, pour out the upper water to obtain amino-modified phosphate-modified phenolic resin;

[0030] (5) Add 7 g of amino-modified phosphate-modified phenolic resin, 12 g of intermediate 2, and 0.02 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 30°C for 2 h. After the reaction is completed, filter, wash, and dry to obtain adamantane-modified phosphate-modified phenolic resin;

[0031] (6) Add ethylene glycol butyl ether solvent to the reactor and heat to 110°C. Mix 18 parts by weight of methyl methacrylate, 7 parts by weight of butyl acrylate, 4 parts by weight of styrene, 0.2 parts by weight of benzoyl peroxide initiator, and 0.1 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled within 2.5 hours. After the addition is completed, keep the temperature and react for 50 minutes.

[0032] (7) 16 parts by weight of hydroxyethyl methacrylate, 10 parts by weight of acrylic acid, 3 parts by weight of sulfonate-modified epoxy resin, 2 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.3 parts by weight of benzoyl peroxide initiator, and 0.2 parts by weight of dodecyl mercaptan chain transfer agent were mixed and added dropwise to the reaction solution of step (6). The addition time was controlled within 1 hour. After the addition was completed, the mixture was kept warm for 1.5 hours. After the reaction was completed, the solvent was evaporated, 0.3 parts by weight of dimethylethanolamine as a neutralizer was added and stirred for 15 minutes, and deionized water was added for dispersion to obtain a hydroxypropyl emulsion with a long activation period for plywood glue. Example 2

[0033] (1) Add 12 g of 1-naphthol-5-sulfonic acid and 20 g of phosphorus oxychloride to a single-necked flask, heat to 80°C, reflux for 8 h, and then remove the remaining phosphorus oxychloride under reduced pressure. Add 0.07 g of triethylamine catalyst dropwise at 5°C. After the addition is complete, add 10 g of 3-butene-1-ol and react at 28°C for 12 h. After the reaction is complete, filter and distill under reduced pressure to obtain intermediate 1.

[0034] (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 98°C to form a homogeneous phase, add ethyl triphenyl phosphonium bromide catalyst, wherein the mass ratio of intermediate 1, bisphenol A epoxy resin and ethyl triphenyl phosphonium bromide is 1:3.6:0.08, heat to 160°C at a rate of 4°C / min, react for 70 minutes, cool after the reaction, wash and dry to obtain sulfonate modified epoxy resin;

[0035] (3) Add 18 g of 3-hydroxy-1-adamantyl methacrylate, 9 g of ethylene (chloromethyl) dimethoxysilane, 0.06 g of potassium hydroxide catalyst, and 0.07 g of 4-methoxyphenol polymerization inhibitor to tetrahydrofuran solvent, stir and mix, and react at 48 ° C for 2.5 h. After the reaction is completed, filter, wash and dry to obtain intermediate 2;

[0036] (4) Add 14 g of phenol, 30 g of formaldehyde aqueous solution, and 0.1 g of oxalic acid catalyst to deionized water, wherein the mass fraction of the formaldehyde aqueous solution is 38%, stir and mix, react at 92 ° C for 4 h, add 2 g of 2-amino-5-methylphenylphosphoric acid, and continue to react for 2 h. After the reaction is completed, add deionized water, wash with water for 50 min, and then let it stand for 24 h. After stratification, pour out the upper water to obtain amino-modified phosphate-modified phenolic resin;

[0037] (5) Add 9 g of amino-modified phosphate-modified phenolic resin, 14 g of intermediate 2, and 0.05 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 35°C for 4 h. After the reaction is completed, filter, wash, and dry to obtain adamantane-modified phosphate-modified phenolic resin;

[0038] (6) Add ethylene glycol butyl ether solvent to the reactor, heat to 120°C, mix 22 parts by weight of methyl methacrylate, 10 parts by weight of butyl acrylate, 6 parts by weight of styrene, 0.6 parts by weight of benzoyl peroxide initiator, and 0.3 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled within 3 hours. After the addition is completed, keep the temperature and react for 70 minutes.

[0039] (7) 20 parts by weight of hydroxyethyl methacrylate, 18 parts by weight of acrylic acid, 6 parts by weight of sulfonate-modified epoxy resin, 5 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.8 parts by weight of benzoyl peroxide initiator, and 0.4 parts by weight of dodecyl mercaptan chain transfer agent were mixed and added dropwise to the reaction solution of step (6). The addition time was controlled within 1.5 hours. After the addition was completed, the mixture was kept warm for 2 hours. After the reaction was completed, the solvent was evaporated, 0.6 parts by weight of dimethylethanolamine as a neutralizer was added and stirred for 20 minutes, and deionized water was added for dispersion to obtain a hydroxypropyl emulsion with a long activation period for plywood glue. Example 3

[0040] (1) Add 10 g of 1-naphthol-5-sulfonic acid and 17.5 g of phosphorus oxychloride to a single-necked flask, heat to 76°C, reflux for 7.5 h, and then remove the remaining phosphorus oxychloride under reduced pressure. Add 0.06 g of triethylamine catalyst dropwise at 2°C. After the addition is complete, add 9 g of 3-butene-1-ol and react at 26°C for 11 h. After the reaction is complete, filter and distill under reduced pressure to obtain intermediate 1.

[0041] (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 94°C to form a homogeneous phase, add ethyl triphenyl phosphonium bromide catalyst, wherein the mass ratio of intermediate 1, bisphenol A epoxy resin and ethyl triphenyl phosphonium bromide is 1:3.5:0.06, heat to 155°C at a rate of 3°C / min, react for 60 minutes, cool after the reaction, wash and dry to obtain sulfonate modified epoxy resin;

[0042] (3) Add 16.5 g of 3-hydroxy-1-adamantyl methacrylate, 8 g of ethylene (chloromethyl) dimethoxysilane, 0.04 g of potassium hydroxide catalyst, and 0.06 g of 4-methoxyphenol polymerization inhibitor to tetrahydrofuran solvent, stir and mix, and react at 44 ° C for 2.3 h. After the reaction is completed, filter, wash and dry to obtain intermediate 2;

[0043] (4) Add 12 g of phenol, 26 g of formaldehyde aqueous solution, and 0.09 g of oxalic acid catalyst to deionized water, wherein the mass fraction of the formaldehyde aqueous solution is 37%, stir and mix, react at 90 ° C for 3.5 h, add 1.8 g of 2-amino-5-methylphenylphosphoric acid, and continue to react for 1.8 h. After the reaction is completed, add deionized water, wash with water for 45 min, and then let it stand for 22 h. After stratification, pour out the upper water to obtain amino-modified phosphate-modified phenolic resin;

[0044] (5) Add 8 g of amino-modified phosphate-modified phenolic resin, 13 g of intermediate 2, and 0.03 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 32°C for 3 h. After the reaction is completed, filter, wash, and dry to obtain adamantane-modified phosphate-modified phenolic resin;

[0045] (6) Add ethylene glycol butyl ether solvent to the reactor and heat to 115°C. Mix 20 parts by weight of methyl methacrylate, 9 parts by weight of butyl acrylate, 5 parts by weight of styrene, 0.4 parts by weight of benzoyl peroxide initiator, and 0.2 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled within 2.7 hours. After the addition is completed, keep the temperature and react for 60 minutes.

[0046] (7) 18 parts by weight of hydroxyethyl methacrylate, 14 parts by weight of acrylic acid, 5 parts by weight of sulfonate-modified epoxy resin, 3 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.6 parts by weight of benzoyl peroxide initiator, and 0.3 parts by weight of dodecyl mercaptan chain transfer agent were mixed and added dropwise to the reaction solution of step (6). The addition time was controlled within 1.2 hours. After the addition was completed, the mixture was kept warm for 1.7 hours. After the reaction was completed, the solvent was evaporated, 0.4 parts by weight of dimethylethanolamine as a neutralizer was added and stirred for 18 minutes, and deionized water was added for dispersion to obtain a hydroxypropyl emulsion with a long activation period for plywood glue. Example 4

[0047] (1) Add 8 g of 1-naphthol-5-sulfonic acid and 15 g of phosphorus oxychloride to a single-necked flask, heat to 72°C, reflux for 7 h, and then remove the remaining phosphorus oxychloride under reduced pressure. Add 0.05 g of triethylamine catalyst dropwise at 0°C. After the addition is complete, add 8 g of 3-butene-1-ol and react at 25°C for 10 h. After the reaction is complete, filter and distill under reduced pressure to obtain intermediate 1.

[0048] (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 90°C to form a homogeneous phase, add ethyl triphenyl phosphonium bromide catalyst, wherein the mass ratio of intermediate 1, bisphenol A epoxy resin and ethyl triphenyl phosphonium bromide is 1:3.4:0.04, heat to 150°C at a rate of 2°C / min, react for 50 minutes, cool after the reaction, wash and dry to obtain sulfonate modified epoxy resin;

[0049] (3) Add 18 g of 3-hydroxy-1-adamantyl methacrylate, 9 g of ethylene (chloromethyl) dimethoxysilane, 0.06 g of potassium hydroxide catalyst, and 0.07 g of 4-methoxyphenol polymerization inhibitor to tetrahydrofuran solvent, stir and mix, and react at 48 ° C for 2.5 h. After the reaction is completed, filter, wash and dry to obtain intermediate 2;

[0050] (4) Add 14 g of phenol, 30 g of formaldehyde aqueous solution, and 0.1 g of oxalic acid catalyst to deionized water, wherein the mass fraction of the formaldehyde aqueous solution is 38%, stir and mix, react at 92 ° C for 4 h, add 2 g of 2-amino-5-methylphenylphosphoric acid, and continue to react for 2 h. After the reaction is completed, add deionized water, wash with water for 50 min, and then let it stand for 24 h. After separation, pour out the upper water to obtain amino-modified phosphate modified phenolic resin;

[0051] (5) Add 8 g of amino-modified phosphate-modified phenolic resin, 13 g of intermediate 2, and 0.03 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 32°C for 3 h. After the reaction is completed, filter, wash, and dry to obtain adamantane-modified phosphate-modified phenolic resin;

[0052] (6) Add ethylene glycol butyl ether solvent to the reactor and heat to 115°C. Mix 20 parts by weight of methyl methacrylate, 9 parts by weight of butyl acrylate, 5 parts by weight of styrene, 0.4 parts by weight of benzoyl peroxide initiator, and 0.2 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled within 2.7 hours. After the addition is completed, keep the temperature and react for 60 minutes.

[0053] (7) 18 parts by weight of hydroxyethyl methacrylate, 14 parts by weight of acrylic acid, 5 parts by weight of sulfonate-modified epoxy resin, 3 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.6 parts by weight of benzoyl peroxide initiator, and 0.3 parts by weight of dodecyl mercaptan chain transfer agent were mixed and added dropwise to the reaction solution of step (6). The addition time was controlled within 1.2 hours. After the addition was completed, the mixture was kept warm for 1.7 hours. After the reaction was completed, the solvent was evaporated, 0.4 parts by weight of dimethylethanolamine as a neutralizer was added and stirred for 18 minutes, and deionized water was added for dispersion to obtain a hydroxypropyl emulsion with a long activation period for plywood glue. Example 5

[0054] (1) Add 12 g of 1-naphthol-5-sulfonic acid and 20 g of phosphorus oxychloride to a single-necked flask, heat to 80°C, reflux for 8 h, and then remove the remaining phosphorus oxychloride under reduced pressure. Add 0.07 g of triethylamine catalyst dropwise at 5°C. After the addition is complete, add 10 g of 3-butene-1-ol and react at 28°C for 12 h. After the reaction is complete, filter and distill under reduced pressure to obtain intermediate 1.

[0055] (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 98°C to form a homogeneous phase, add ethyl triphenyl phosphonium bromide catalyst, wherein the mass ratio of intermediate 1, bisphenol A epoxy resin and ethyl triphenyl phosphonium bromide is 1:3.6:0.08, heat to 160°C at a rate of 4°C / min, react for 70 minutes, cool after the reaction, wash and dry to obtain sulfonate modified epoxy resin;

[0056] (3) Add 16.5 g of 3-hydroxy-1-adamantyl methacrylate, 8 g of ethylene (chloromethyl) dimethoxysilane, 0.04 g of potassium hydroxide catalyst, and 0.06 g of 4-methoxyphenol polymerization inhibitor to tetrahydrofuran solvent, stir and mix, and react at 44 ° C for 2.3 h. After the reaction is completed, filter, wash and dry to obtain intermediate 2;

[0057] (4) Add 12 g of phenol, 26 g of formaldehyde aqueous solution, and 0.09 g of oxalic acid catalyst to deionized water, wherein the mass fraction of the formaldehyde aqueous solution is 37%, stir and mix, react at 90 ° C for 3.5 h, add 1.8 g of 2-amino-5-methylphenylphosphoric acid, and continue to react for 1.8 h. After the reaction is completed, add deionized water, wash with water for 45 min, and then let it stand for 22 h. After stratification, pour out the upper water to obtain amino-modified phosphate-modified phenolic resin;

[0058] (5) Add 7 g of amino-modified phosphate-modified phenolic resin, 12 g of intermediate 2, and 0.02 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 30°C for 2 h. After the reaction is completed, filter, wash, and dry to obtain adamantane-modified phosphate-modified phenolic resin;

[0059] (6) Add ethylene glycol butyl ether solvent to the reactor and heat to 110°C. Mix 18 parts by weight of methyl methacrylate, 7 parts by weight of butyl acrylate, 4 parts by weight of styrene, 0.2 parts by weight of benzoyl peroxide initiator, and 0.1 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled within 2.5 hours. After the addition is completed, keep the temperature and react for 50 minutes.

[0060] (7) 16 parts by weight of hydroxyethyl methacrylate, 10 parts by weight of acrylic acid, 3 parts by weight of sulfonate-modified epoxy resin, 2 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.3 parts by weight of benzoyl peroxide initiator, and 0.2 parts by weight of dodecyl mercaptan chain transfer agent were mixed and added dropwise to the reaction solution of step (6). The addition time was controlled within 1 hour. After the addition was completed, the mixture was kept warm for 1.5 hours. After the reaction was completed, the solvent was evaporated, 0.3 parts by weight of dimethylethanolamine as a neutralizer was added and stirred for 15 minutes, and deionized water was added for dispersion to obtain a hydroxypropyl emulsion with a long activation period for plywood glue.

[0061] Comparative Example 1

[0062] This comparative example is different from Example 5 in that no adamantane-modified phosphate-modified phenolic resin is added.

[0063] Comparative Example 2

[0064] Compared with Example 5, this comparative example differs in that no sulfonate-modified epoxy resin is added.

[0065] The hydroxypropyl emulsion prepared in Example 1-5 and Comparative Example 1-2 was mixed with toluene diisocyanate in a ratio of 8:1 at 600 rpm for 3-5 minutes to obtain a panel glue.

[0066] The panel glue was placed in a 35°C / 60%RH constant temperature and humidity test chamber for an activation period test. The test results are shown in Table 1.

[0067] Table 1: Pot life test.

[0068] project Activation period (min) Example 1 63 Example 2 70 Example 3 68 Example 4 74 Example 5 66 Comparative Example 1 42 Comparative Example 2 47

[0069] As can be seen from Table 1, the plywood glue prepared from the hydroxypropylene emulsion in Examples 1-5 has a longer activation period than the plywood glue prepared from the hydroxypropylene emulsion in Comparative Examples 1-2.

[0070] Apply the glue to the base material, which is solid wood, with a glue application amount of 180g / m 2 , place it for 1.5 hours, boil it in 100℃ water for 6 hours, and then bake it in an 80℃ oven for 20 hours. If the glue does not come off after baking for 20 hours, the glue of the puzzle board is qualified; if the glue comes off after baking for 20 hours, the glue of the puzzle board is unqualified. The test results are shown in Table 2:

[0071] Table 2: High temperature resistance test.

[0072] project High temperature resistance Example 1 qualified Example 2 qualified Example 3 qualified Example 4 qualified Example 5 qualified Comparative Example 1 Unqualified Comparative Example 2 Unqualified

[0073] As can be seen from Table 2, the test results of the puzzle glue made from the hydroxypropylene emulsion in Examples 1-5 are qualified; the test results of the puzzle glue made from the hydroxypropylene emulsion in Comparative Examples 1-2 are unqualified, indicating that the puzzle glue prepared with the long activation period hydroxypropylene emulsion has better high temperature resistance.

[0074] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A long-activation-period hydroxypropyl emulsion for plywood glue, characterized in that: The invention comprises the following components by weight: 18-22 parts by weight of methyl methacrylate, 7-10 parts by weight of butyl acrylate, 4-6 parts by weight of styrene, 16-20 parts by weight of hydroxyethyl methacrylate, 10-18 parts by weight of acrylic acid, 3-6 parts by weight of sulfonate-modified epoxy resin, and 2-5 parts by weight of adamantane-modified phosphate-modified phenolic resin; The preparation method of the sulfonate-modified epoxy resin comprises the following steps: (1) Add 8-12 g of 1-naphthol-5-sulfonic acid and 15-20 g of phosphorus oxychloride to a single-necked flask, heat and reflux for 7-8 h, then remove the remaining phosphorus oxychloride under reduced pressure, add 0.05-0.07 g of triethylamine catalyst dropwise at 0-5 ° C, and then add 8-10 g of 3-butene-1-ol, react at 25-28 ° C for 10-12 h, filter and distill under reduced pressure to obtain intermediate 1; (2) Add intermediate 1 and bisphenol A epoxy resin to a three-necked flask, stir and mix at 90-98°C to form a homogeneous phase, add ethyltriphenylphosphonium bromide catalyst, heat to 150-160°C at a rate of 2-4°C / min, and react for 50-70 minutes. After the reaction is completed, cool, wash and dry to obtain a sulfonate-modified epoxy resin; The preparation method of the adamantane-modified phosphate-modified phenolic resin comprises the following steps: S1. To tetrahydrofuran solvent were added 15-18 g of 3-hydroxy-1-adamantyl methacrylate, 7-9 g of ethylene (chloromethyl) dimethoxysilane, 0.03-0.06 g of potassium hydroxide catalyst, and 0.05-0.07 g of 4-methoxyphenol polymerization inhibitor, stirred and mixed, and reacted for 2-2.5 h. After the reaction, the mixture was filtered, washed, and dried to obtain intermediate 2; S2. 10-14 g of phenol, 22-30 g of formaldehyde solution, 0.08-0.1 g of oxalic acid catalyst were added to deionized water, stirred and mixed, and reacted at 88-92 ° C for 3-4 h, and then 1.5-2 g of 2-amino-5-methylphenyl phosphoric acid was added thereto. The reaction was continued for 1.5-2 h. After the reaction was completed, deionized water was added, washed with water for 40-50 min, and then allowed to stand for 20-24 h. After separation, the upper layer of water was poured out to obtain an amino-modified phosphate-modified phenolic resin; S3. Add 7-9 g of amino-modified phosphate-modified phenolic resin, 12-14 g of intermediate 2, and 0.02-0.05 g of sodium ethoxide catalyst to tetrahydrofuran solvent, stir and mix, and react at 30-35°C for 2-4 hours. After the reaction is completed, filter, wash and dry to obtain adamantane-modified phosphate-modified phenolic resin.

2. The long-activation-period hydroxypropyl emulsion for plywood glue according to claim 1, characterized in that: The temperature of the reflux reaction in step (1) is 72-80°C.

3. The long-activation-period hydroxypropyl emulsion for plywood glue according to claim 1, characterized in that: In the step (2), the mass ratio of the intermediate 1, bisphenol A epoxy resin, and ethyl triphenyl phosphonium bromide is 1:3.4-3.6:0.04-0.

08.

4. The long-activation-period hydroxypropyl emulsion for plywood glue according to claim 1, characterized in that: The reaction temperature in S1 is 40-48°C.

5. The long-activation-period hydroxypropyl emulsion for plywood glue according to claim 1, characterized in that: The mass fraction of the formaldehyde aqueous solution in S2 is 36%-38%.

6. A long-activation-period hydroxypropyl emulsion for plywood glue according to claim 1, characterized in that: The preparation method of the long-activation-period hydroxypropyl emulsion for the puzzle glue comprises the following steps: Step 1: Add ethylene glycol butyl ether solvent to the reactor, heat to 110-120 ° C, mix 18-22 parts by weight of methyl methacrylate, 7-10 parts by weight of butyl acrylate, 4-6 parts by weight of styrene, 0.2-0.6 parts by weight of benzoyl peroxide initiator, and 0.1-0.3 parts by weight of dodecyl mercaptan chain transfer agent, and add the mixture dropwise to the ethylene glycol butyl ether solvent. The addition time is controlled to be 2.5-3 hours. After the addition is completed, keep the mixture warm for 50-70 minutes. Step 2: Mix 16-20 parts by weight of hydroxyethyl methacrylate, 10-18 parts by weight of acrylic acid, 3-6 parts by weight of sulfonate-modified epoxy resin, 2-5 parts by weight of adamantane-modified phosphate-modified phenolic resin, 0.3-0.8 parts by weight of benzoyl peroxide initiator, and 0.2-0.4 parts by weight of dodecyl mercaptan chain transfer agent, and add them dropwise to the reaction solution of step 1. The addition time is controlled at 1-1.5 hours. After the addition is completed, keep warm and react for 1.5-2 hours. After the reaction is completed, evaporate the solvent, add 0.3-0.6 parts by weight of dimethylethanolamine neutralizer and stir for 15-20 minutes, add deionized water to disperse, and obtain a hydroxypropyl emulsion with a long activation period for puzzle glue.