High-softening-point rosin resin tackifying emulsion for improving initial viscosity and peel strength of water-based adhesive as well as high-pressure reversal preparation method and application of high-softening-point rosin resin tackifying emulsion
By compounding anionic and nonionic surfactants in a specific ratio and combining it with the high-pressure reversal method to prepare a high-softening point rosin resin tackifying emulsion, the problem of insufficient initial adhesion and peel strength of rosin glycerol ester emulsion in water-based adhesives was solved, and efficient and environmentally friendly water-based adhesive modification was achieved.
Patent Information
- Application Number
- CN202510721600.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-09-19
AI Technical Summary
Existing rosin glycerol ester emulsions in water-based adhesives have limited improvement in initial adhesion and peel strength, and the emulsification process requires the use of organic solvents, which leads to problems such as high cost, multiple steps and severe environmental pollution.
Anionic surfactants, nonionic surfactants and emulsifiers are compounded in a specific proportion, and a high-softening point rosin resin tackifying emulsion is prepared by a high-pressure reversal method. The amount of emulsifier is small, which significantly improves the initial adhesion and peel strength of the water-based adhesive and reduces the impact on the stickiness.
The prepared high softening point rosin resin tackifying emulsion significantly improves the initial adhesion and peel strength of water-based adhesives, requires less emulsifier, has high stability, is simple to operate, is environmentally friendly and pollution-free, is suitable for high-speed coating, and has low cost.
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Figure CN120665446A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a high-softening-point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive, a high-pressure reversal preparation method thereof and application thereof, and belongs to the technical field of water-based tackifying emulsions. Background Art
[0002] Replacing fossil resources with biomass resources in the development of chemicals, energy, and materials can significantly reduce carbon emissions. Developing the chemical industry using biomass resources instead of fossil resources is an essential path to sustainable human development. Rosin is a significant renewable natural resource in my country's forestry sector, with an annual production of over 400,000 tons. It is widely used in adhesives, inks, coatings, and other fields. To address the current challenges of low adhesive strength and low bio-based content in adhesives, the development of high-strength rosin-based water-based adhesives using biomass rosin as raw material has broad application prospects.
[0003] Water-based tackifying emulsions are used in water-based adhesives to improve the adhesive's bonding properties. Currently, the most widely used is rosin glycerol ester emulsion, which is added to water-based acrylic emulsions through physical blending and accounts for 15-20% of water-based pressure-sensitive adhesives. However, rosin glycerol ester emulsions only provide limited improvement in the initial tack and peel strength of water-based adhesives, and have a significant impact on the sustained tack. Initial tack, peel strength, and sustained tack are core performance indicators of water-based pressure-sensitive adhesives and directly determine the adhesive's reliability and suitability in practical applications. Therefore, there is an urgent need to develop water-based tackifying emulsions that can significantly improve the initial tack and peel strength of water-based adhesives while minimizing the impact on sustained tack.
[0004] The higher the softening point of rosin resin, the harder it is to emulsify and the more difficult it is to transition to a new phase. Therefore, preparing aqueous emulsions of high-softening-point rosin resin is quite challenging, limiting their use in water-based adhesives and other applications. While there has been some prior research on resin emulsification, most require the use of organic solvents, leading to high costs, multiple steps, and significant environmental pollution. Furthermore, the high amount of emulsifier required further increases costs. Summary of the Invention
[0005] The present invention provides a high-softening-point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive, a high-pressure reversal preparation method thereof, and applications thereof. The high-emulsifying-point rosin ester tackifying emulsion is obtained by using rosin pentaerythritol ester, maleated rosin glycerol ester, maleated rosin pentaerythritol ester, etc. as main raw materials and adopting a pressure reversal method. The rosin ester tackifying emulsion can significantly improve the initial tack and peel strength of the water-based adhesive while significantly reducing the effect on the lasting tack. Furthermore, the amount of emulsifier used is small, and the obtained emulsion has high stability.
[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:
[0007] A high-softening-point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive. The emulsifier used is a complex of anionic surfactant, nonionic surfactant, and emulsifier in a mass ratio of 1:(1.5-2.5):(0.1-0.3); wherein the anionic surfactant is at least one of sodium dodecylbenzenesulfonate, calcium dodecylbenzenesulfonate, sodium lauryl sulfate, or sodium fatty alcohol polyoxyethylene ether sulfate; the nonionic surfactant is at least one of isomeric alcohol polyoxyethylene ether, stearic acid polyoxyethylene ester, or castor oil polyoxyethylene ether; and the emulsifier is at least one of triethanolamine or triethylamine.
[0008] The selection of emulsifier is one of the key factors in the preparation of emulsion. The applicant has found through research that the emulsifier with the above ratio effectively accelerates emulsification, while improving the stability of the emulsion and taking into account the improvement effect on the adhesive viscosity.
[0009] Different substances have very strong selectivity for emulsifiers, especially for substances that are difficult to emulsify, the effects of different emulsifiers vary significantly.
[0010] After a long period of selection, the inventor unexpectedly discovered that by compounding the anionic surfactant, nonionic surfactant and emulsifier specifically selected in the present application in a specific ratio, a highly stable high-softening point rosin resin tackified aqueous emulsion can be prepared by a high-pressure reversal method, without the need for compounding solvents. The initial tack and peel strength of the water-based adhesive are significantly improved, and the improvement is significantly greater than expected. At the same time, the impact on the lasting adhesion is significantly reduced. This also shows that the emulsifier of the specific composition of the present application has a significant positive promoting effect on the performance of the high-softening point rosin resin tackified emulsion.
[0011] The high softening point rosin resin in this application refers to a rosin resin with a softening point ≥80°C.
[0012] In order to further ensure the emulsification effect and the stability of the obtained emulsion, the emulsifier is a mixture of calcium dodecylbenzenesulfonate, polyoxyethylene stearate and triethanolamine in a mass ratio of 1: (1.5-2.0): (0.1-0.3).
[0013] The aforementioned selection of specific ingredients and specific ratios of emulsifiers promotes the synergistic effect between the components, which not only promotes the phase transition of the rosin resin, but also improves the stability of the emulsion, and significantly improves the initial tack, sustained tack and peel strength of the glue.
[0014] When preparing a high-softening-point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive, the mass of the emulsifier is 3-8% of the mass of the high-softening-point rosin resin. This means that the present invention can obtain a highly stable and high-performance high-softening-point rosin resin tackifying emulsion using a relatively small amount of emulsifier.
[0015] The high-softening-point rosin resin of the present application preferably has a softening point of 85-160°C. More preferably, the high-softening-point rosin resin is rosin pentaerythritol ester, maleated rosin glycerol ester, or maleated rosin pentaerythritol ester. Rosin pentaerythritol ester, maleated rosin glycerol ester, or maleated rosin pentaerythritol ester, in the presence of the specific emulsifier of the present application, can be used to produce a high-softening-point rosin-based tackifying emulsion through a pressure reversal method.
[0016] The solid content of the high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of the water-based adhesive is 50-65%, which fully meets the requirements for modifying the water-based adhesive.
[0017] The method for preparing the high-softening-point rosin resin tackifying emulsion for improving the initial tack and peel strength of the water-based adhesive adopts a high-pressure reversal method, wherein the high-softening-point rosin resin and an emulsifier are placed in a pressurized reactor, heated to 130-170°C, stirred and melted, and hot water is pumped into the autoclave using a high-pressure delivery pump. The rosin resin is reversed and emulsified, and uniformly dispersed in water to obtain the high-softening-point rosin resin tackifying emulsion.
[0018] The above-mentioned heating of the rosin resin to 130-150° C. and stirring and melting can better ensure the dispersibility of the rosin resin and the stability of the resulting emulsion; the present application is carried out in a pressurized reactor, which, on the one hand, can prevent water volatilization and, on the other hand, can facilitate the control of the reaction and ensure the dispersibility and stability of the emulsion.
[0019] In order to better ensure the dispersion effect of the emulsion, the pressure in the pressure reactor is 6±0.2 kg.
[0020] To improve emulsification efficiency, the temperature of the hot water pumped in should be 95-99°C. Hot water at a temperature of 95-99°C can promote rapid phase inversion and emulsification of rosin resin.
[0021] To ensure the emulsification effect and the performance of the resulting emulsion, before phase inversion, the hot water pumped in at an hourly rate of 20-30% of the mass of the high-softening-point rosin resin; after phase inversion, the hot water pumped in at an hourly rate of 1-1.2 times the mass of the high-softening-point rosin resin; after the emulsion is prepared, it is naturally cooled to 50-60°C and then water-cooled to room temperature.
[0022] The high softening point rosin resin tackifying emulsion is used to improve the initial tack and peel strength of water-based adhesives. When used, the addition amount of the high softening point rosin resin tackifying emulsion to the water-based adhesive is 13-17%.
[0023] The high-softening-point rosin resin tackifying emulsion has excellent fluidity at room temperature and can be applied by brushing, dipping, pouring, spraying, or roller coating. This overcomes the shortcoming of hot-melt adhesives that only have fluidity at higher temperatures, reduces the operating temperature, and protects the substrate. It has high bonding strength, is made from inexpensive and readily available raw materials, uses environmentally friendly water as a dissolving and dispersing medium, is biodegradable, and is a new type of high-tech environmentally friendly product.
[0024] The high softening point rosin resin tackifying emulsion has a small particle size, good stability, and no stratification when stored at room temperature for 12 months; the solid content reaches 50-65%; the raw materials are cheap and easily available, and environmentally friendly water is used as a solvent, and it is biodegradable.
[0025] The water-based adhesive of this application is preferably acrylic emulsion 7115.
[0026] Unless otherwise specified, all % in this application are by mass percentage.
[0027] The technologies not mentioned in this invention are all referred to the prior art.
[0028] The present invention achieves the following beneficial effects:
[0029] 1) The present invention adopts high-pressure emulsification to uniformly disperse the high-softening-point rosin resin in water, thereby obtaining a stable aqueous tackifying emulsion, enhancing the bonding strength, and the preparation process is simple, easy to operate, and easy to control;
[0030] 2) Emulsifiers are widely available, require little usage, are low cost, and have a significant positive effect on the application performance of aqueous thickening emulsions;
[0031] 3) The aqueous tackifying emulsion prepared by the present invention can significantly improve the initial adhesion and peel strength of water-based adhesives;
[0032] 4) The thickening emulsion of the present invention has good fluidity at room temperature, is suitable for high-speed coating, and improves work efficiency; the dispersion medium is water, and no organic solvent is required, which is low in cost, environmentally friendly and pollution-free, and will not damage the substrate. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Figure 1 This is the particle size distribution diagram of the high softening point rosin tackifying emulsion obtained in Example 1; DETAILED DESCRIPTION
[0034] In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples.
[0035] All reactions were carried out at room temperature (15-25°C) unless otherwise specified.
[0036] Example 1
[0037] A high softening point rosin resin tackifying emulsion and its pressurized reversal method preparation method: weigh rosin pentaerythritol ester (softening point 100 ° C, acid value 18mg The mixture was stirred at 130 ° C under a pressure of 6 kg, and the mixture was melted and stirred rapidly (1500 r / min). 97 ° C distilled water was slowly pumped in with a high-pressure pump (200 g / h). After 1.5 h, the phase was successfully inverted and the water addition rate was increased to 1000 g / h until a total of 793 g of water was added. After the addition of water was completed, the stirring rate was reduced to 200 r / min, the heat source was turned off, the temperature was naturally lowered to 50 ° C, and then cooled to below 35 ° C with cold water. The stirring was stopped, and the mixture was filtered with a filter (aperture 1 mm), the discharging was bottled to obtain an aqueous thickening emulsion with a solid content of 55% and a viscosity of 230 mPa / s.
[0038] Example 2
[0039] The particle size of the rosin-based aqueous tackifying emulsion was analyzed using an APA 2000 laser diffraction particle size analyzer. Figure 1 As shown, the average particle size of the aqueous thickening emulsion is 320nm; the stability (standing at room temperature) is greater than 12 months.
[0040] Example 3
[0041] The water-based pressure-sensitive adhesive was prepared using acrylic emulsion 7115 (BASF, Anguli 7115) as the base emulsion (initial tack of 11 N / 25 mm and peel strength of 7 N / 25 mm). 85 g of the 7115 emulsion and 15 g of the aqueous tackifying emulsion prepared in Example 1 were mixed and applied to a glass plate. After drying, the initial tack and peel strength were tested. Initial tack was tested using the GB / T31125-2014 method, sustained tack was tested using the GB / T4851-2014 method, and peel strength was tested using the GB / T2792-2014 method. The mechanical properties are shown in the following table:
[0042] Table 1
[0043]
[0044] As shown in the table above, the addition of the water-based tackifying emulsion increased the initial tack of the water-based adhesive by 112.4% and the peel strength by 48.7%. These improvements were more significant than those achieved with existing commercially available tackifying emulsions. Furthermore, the sustained adhesion was increased by 85.3% compared to the use of commercially available tackifying emulsions.
[0045] Comparative Example 1
[0046] The difference from Example 1 was that the emulsifier was replaced with 70 g of calcium dodecylbenzenesulfonate. The rest of the process was the same as in Example 1. The phase inversion failed and stratification occurred after cooling.
[0047] Comparative Example 2
[0048] The difference from Example 1 is that calcium dodecylbenzenesulfonate is replaced by sodium stearate. The rest is the same as Example 1. The obtained emulsion is separated into layers after cooling.
[0049] Comparative Example 3
[0050] The difference from Example 1 is that the emulsifier is replaced with 70g of polyoxyethylene stearate (SG-12, Haianshihua). The rest are referred to Example 1. The phase inversion fails and no uniform emulsion is obtained.
[0051] Comparative Example 4
[0052] The difference from Example 1 was that the emulsifier was replaced with 70 g of triethanolamine. The rest was the same as in Example 1. However, the phase inversion failed and no uniform emulsion was obtained.
[0053] Comparative Example 5
[0054] The difference from Example 1 is that calcium dodecylbenzenesulfonate was replaced by sodium diisooctyl sulfosuccinate. The rest of the process was the same as that of Example 1. However, the phase inversion failed.
Claims
1. A high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive, characterized by: The emulsifier used is a complex of anionic surfactant, nonionic surfactant and emulsifier in a mass ratio of 1:(1.5-2.5):(0.1-0.3); wherein the anionic surfactant is at least one of sodium dodecylbenzenesulfonate, calcium dodecylbenzenesulfonate, sodium lauryl sulfate or sodium fatty alcohol polyoxyethylene ether sulfate; the nonionic surfactant is at least one of isomeric alcohol polyoxyethylene ether, stearic acid polyoxyethylene ester or castor oil polyoxyethylene ether; and the emulsifier is at least one of triethanolamine or triethylamine.
2. The high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of the water-based adhesive according to claim 1, characterized in that: The emulsifier is a mixture of calcium dodecylbenzenesulfonate, polyoxyethylene stearate and triethanolamine in a mass ratio of 1: (1.5-2.0): (0.1-0.3).
3. The high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of water-based adhesive according to claim 1 or 2, characterized in that: The mass dosage of the emulsifier is 3 to 8% of the mass of the high softening point rosin resin.
4. The high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of water-based adhesive according to claim 1 or 2, characterized in that: The softening point of high softening point rosin resin is 85-160°C.
5. The high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of water-based adhesive according to claim 1 or 2, characterized in that: The high softening point rosin resins include pentaerythritol ester of rosin, glycerol ester of maleated rosin, and pentaerythritol ester of maleated rosin.
6. The high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of water-based adhesive according to claim 1 or 2, characterized in that: Its solid content is 50-65%.
7. A method for preparing the high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive according to any one of claims 1 to 6, using a high pressure reversal method, characterized in that: Put high softening point rosin resin and emulsifier into a pressurized reactor, heat to 130-170℃, stir and melt, pump hot water into the autoclave with a high-pressure delivery pump, reverse the emulsification of the rosin resin and evenly disperse it in water to prepare a high softening point rosin resin tackifying emulsion.
8. The preparation method according to claim 7, wherein: The pressure in the pressure reactor is 6±0.2 kg.
9. The preparation method according to claim 7 or 8, wherein: The temperature of the hot water pumped in is 95-99°C; the amount of hot water pumped in per hour is 20-30% of the mass of the high softening point rosin resin; after the emulsion is prepared, it is naturally cooled to 50-60°C and then water-cooled to room temperature.
10. Use of the high softening point rosin resin tackifying emulsion for improving the initial tack and peel strength of a water-based adhesive according to any one of claims 1 to 6, characterized in that: Used to improve the initial adhesion and peel strength of water-based adhesives, the addition amount of high softening point rosin resin tackifying emulsion in water-based adhesives is 13-17%.