JP3101927B2 - Method for producing petroleum resin aqueous emulsion - Google Patents

Description

The present invention relates to a method for producing an aqueous emulsion of a petroleum resin.

[Prior Art] When an aqueous emulsion is used as the base resin of the adhesive, a tackifier resin is also generally used in the aqueous emulsion. The method of aqueous emulsification of the tackifying resin is 3
It is roughly divided into two. 1) High pressure emulsification-solvent removal method, 2) Normal pressure phase inversion emulsification method, and 3) Pressure phase inversion emulsification method.

In the high-pressure emulsification-solvent removal method, a tackifier resin is dissolved in a large amount of an organic solvent, and an emulsifying dispersant and water are added thereto to obtain a coarse emulsion, and then a high shear emulsifier (for example, a Gaulin high-pressure emulsifier) is used. This is a method for producing an O / W type emulsion by performing forced emulsification. This method generally requires a large amount of solvent removal in order to obtain a practical active ingredient concentration, and it is difficult to completely remove the solvent due to the safety of handling in the process, the problem of long time and heat energy loss, and the complete removal of the solvent. In addition, odor and safety issues during use are pointed out.

The normal-pressure phase inversion emulsification method has a limitation in that, in the case of a tackifying resin having a high softening point, aqueous emulsification is impossible without using a solvent, and the solvent is not contained. In addition, when solvents are used, a decrease in the softening point of the resin and a decrease in the adhesive force and cohesive force of the adhesive obtained using this emulsion are caused. The pressure phase inversion emulsification method is a known method as shown in Japanese Patent Application Laid-Open No. 40585/1988, so that it is subjected to a pressure higher than the atmospheric pressure and a temperature higher than the softening point of the resin as compared with the above two methods. Since no solvent is used for emulsification by using the above method, the method has many advantages as compared with the above two methods and is a good method. However, in this pressure emulsification method, selection of an emulsifying dispersant
Importantly, it is not easy to obtain an emulsion having a uniform particle size and good stability over time. Originally, O / W emulsions are heterogeneous and unstable systems in which water is the continuous phase and the emulsified material is the discontinuous phase. Therefore, an emulsifying and dispersing agent having more excellent emulsifiability and stability has been demanded.

[Problems to be solved by the invention]

In recent years, a solvent-free aqueous emulsion of a tackifying resin has been demanded in view of general-purpose use of adhesives and accompanying safety. Usually, as the method of aqueous emulsion of the tackifier resin, there are mainly the above three methods,
From the viewpoint of the solvent-free emulsion, a pressure emulsification method in which the emulsion is formed at a temperature equal to or higher than the softening point of the tackifying resin and at a pressure equal to or higher than the atmospheric pressure is employed. The pressure emulsification method is
In general, the emulsifying dispersant to be used must be carefully selected because it is performed under severe conditions under a pressure of 100 ° C. or higher and an atmospheric pressure or higher.

For example, JP-A-64-40585 and JP-A-2-149330
Emulsifying dispersant, polyoxyethylene alkylphenoxy 2-hydroxypropane sulfonate,
Even when a nonionic ethoxylated alkylphenol, anionic alkylarylsulfonate, rosin soap, or the like is used as an emulsifying dispersant, it is difficult to obtain a uniform emulsion having a small particle size and good stability over time. The present invention aims to solve such a problem and proposes a method for obtaining an emulsion having good emulsification and good stability over time by using a specific emulsifying dispersant.

[Means for solving the problem]

The subject of the present invention does not contain solvents for the tackifying resin,
It is to obtain a stable and good O / W type aqueous emulsion. The present invention relates to forming a W / O emulsion of a petroleum resin at a temperature higher than the softening point of the resin and under a pressure higher than the atmospheric pressure, and then performing a phase transition to obtain a stable O / W emulsion. As an emulsifying dispersant, the following general formula [However, X is -CH ₂ -, Or l is an integer of 1 or 2, R represents -CH ₂ -CH ₂ -, or m is an integer of 3 to ₁₀₀ , R ₁ is hydrogen or CH ₃ — or Y is hydrogen or -SO ₃ Z (Z is a monovalent or divalent cation, amine), however, Y is at least one of the n is SO ₃ Z,
n is 2 or an integer of 2 or more], thereby obtaining a stable emulsion with good emulsification.

The tackifier resin in the present invention refers to olefin, diolefin, and / or
Aromatics, predominantly C ₅ to petroleum resins prepared by polymerization of C ₉ compounds (copolymerization), and hydrogenated products thereof, refers phenol, maleic anhydride, fumaric acid, a modified product by alkylphenol like.

These petroleum resins have a degree of polymerization (copolymerization degree) or
There are various types depending on the combination of the reaction raw materials, from liquid to high softening point of 200 ° C. or more. In the present invention, all of these tackifying resins and mixtures thereof are targeted. Aqueous emulsions require that the tackifying resin having a high softening point because the continuous phase is water generally needs to be emulsified at a temperature at least about 20 ° C. higher than the softening point of the resin. In the case of a tackifying resin at 100 ° C., the emulsification process is necessarily at 100 ° C. or higher unless a solvent is used, and the pressure is higher than the atmospheric pressure. In the present invention, the emulsion at a temperature above the softening point of the resin and under pressure above the atmospheric pressure is intended, but even if the softening point of the tackifying resin is not necessarily as high as 100 ° C. or higher,
For example, even with a tackifying resin having a softening point of 60 ° C., the emulsification process can be carried out using the emulsifying dispersant of the present invention represented by the general formula (1) at 100 ° C. or higher and at a pressure higher than the atmospheric pressure. .

The petroleum resin is used for adding tackiness to a base polymer (for example, natural rubber, synthetic rubber, acrylic resin, etc.) constituting the adhesive agent. Therefore, when the adhesive is oily, the tackifier is also oily, and when the adhesive is aqueous, the tackifier cannot be used unless it is aqueous. Solvents in the present invention, lowering the softening point of petroleum resin, or a diluting solvent used for liquefaction, or process oil, dissolve tackifier resin such as plasticizer, a substance that lowers the apparent softening point say.

The compound of the general formula of the present invention is a polyoxyalkylene obtained by reacting 3 to 100 mol of alkylene oxide with allylphenol obtained by aldehyde condensation of a phenol compound having two or more benzene rings as a hydrophobic group, followed by sulfate esterification. It is a sulfate salt of an aryl ether.

Examples of the phenol compound having two or more benzene rings include the following representative examples of products obtained by reacting phenol with benzyl chloride, styrene, α-methylstyrene, indene, and the like by a Friedel-Crafts reaction. Rukoto can.

Furthermore, the following representative examples can be given as arylphenols obtained as condensates of these aldehydes (formaldehyde, acetaldehyde, benzoaldehyde).

Usually, when a phenol is subjected to Friedel-Crafts reaction of styrene, benzyl chloride, or the like, the resulting product is a styrylated phenol or a benzylated mono-, di-, or tri-substituted phenol. 5 and 7, and mixtures as in Synthesis Examples 6 and 8. After the Friedel-Crafts reaction, the compound as in Synthesis Example 2 or Synthesis Example 4 can be purified and taken out. As for the synthesis of arylphenols as in Synthesis Examples 5 to 8, there are combinations of phenol to styrene monomer and α-methylstyrene to phenol to benzyl chloride, but from the viewpoint of reactivity, workability, economy and the like, phenols to styrene are used. A combination of a monomer and formaldehyde is easily selected, and a formaldehyde condensate of a styrene monomer or a benzyl chloride 2 mol reactant per mol of phenol is preferable.

Addition reactions of alkylene oxides to arylphenols obtained by aldehyde condensation, such as in Synthesis Examples 5 to 8, are known, but there are ethylene oxide and propylene oxide as alkylene oxides, and propylene oxide is a balance as an emulsifying dispersant. It is effective for reducing cold fluidity and reducing the viscosity of the emulsion at the time of emulsion inversion. Alkylene oxides include butylene oxide and styrene oxide, but are not economical due to their effects.

The addition amount of ethylene oxide and ethylene oxide and propylene oxide is 3 to 100 mol, and although it depends on the properties of the tackifying resin of the emulsified substance, if the proportion of alkylene oxide in the molecule is E (%), ethylene In the case of oxide alone, E / 5 is preferably in the range of 10 to 15, and in the case of ethylene oxide and propylene oxide, the molar ratio of ethylene oxide / propylene oxide is 9/1 to 6/4, particularly 9/1 to 8 / 2 range, 10 moles
A range of 5050 mol is preferred. The order of addition of ethylene oxide and propylene oxide does not matter, but it is preferable that the terminal be an ethylene oxide chain.

The polyoxyalkylene aryl ether sulfate salt thus obtained can be obtained by a known method in which chlorsulfonic acid, sulfuric anhydride, sulfamic acid and the like are reacted and then neutralized with an alkali and an amine. The polyoxyalkylene aryl ether, which is an emulsifying dispersant in the present invention, has a plurality of terminal OH groups, and at least one of the OH groups is a sulfate, and those other than the sulfate are hydroxyl groups. Monovalent and divalent cations as salts include sodium, potassium, lithium, calcium, magnesium, and amines include ammonia, alkanolamine, and morpholine. For example, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanol, dimethylethanolamine, diethylethanolamine, trimethylamine, tributylamine and mixtures thereof can be mentioned. Calcium and magnesium are effective when the addition mole number of ethylene oxide is at least three times that of the aryl ether, and an aqueous emulsion having high hard water resistance can be produced.

The method of the present invention is to form a W / O emulsion of a petroleum resin at a temperature above its softening point and at a pressure above atmospheric pressure, then phase-transform it to form an O / W-type emulsion. This is a production method for obtaining an aqueous emulsion of a petroleum resin for obtaining an emulsion.

The emulsifying dispersant listed in the general formula is usually 2 to 10 parts with respect to 100 parts of petroleum resin solid content (the same applies to parts by weight or less) in solid content,
It is preferably used in a proportion of 3 to 7 parts. When the amount is less than 2 parts, the emulsification and dispersion stability is not sufficient, and when the amount exceeds 10 parts, the physical properties of the adhesive such as water resistance and coagulation effect are reduced.
It is also disadvantageous economically.

In the production method of the present invention, first, a petroleum resin is melted at a temperature not lower than its softening point, and then, while stirring the melt, an emulsifying dispersant or an aqueous solution thereof or an aqueous solution of an emulsifying dispersant and water are added thereto, and the mixture is uniformly mixed. Mix. Usually, this is performed at a temperature about 20 ° C. or more higher than the softening point to lower the viscosity of the resin, for example, a petroleum resin having a softening point of 100 ° C. is 120 to 130 ° C.
This is performed under a pressure higher than the atmospheric pressure. Therefore, when adding the emulsifying dispersant aqueous solution and water, it is preferable to inject the water under a pressure of 120 to 130 ° C. or higher, and the W / O type in which the petroleum resin is a continuous phase and the water is a discontinuous phase. An emulsion is formed. The amount of water used at this time is preferably adjusted so that the solid content of the obtained emulsion is 70 to 85%. The temperature of the water to be injected is preferably equal to or higher than the softening point of the resin.
Even below that, it is possible if the temperature of the emulsification tank is considerably higher than the softening point of the tackifier resin.

In addition, W / O which usually vigorously agitates hot water of 70-170 ° C
Add slowly to the mold emulsion. As a result, phase inversion of the emulsion occurs, and an emulsion is formed in which the W / O type to the O / W type petroleum resin is a discontinuous phase and water is a continuous phase.

The amount of water that causes phase inversion depends on the difference in behavior of the petroleum resin with water and the amount of emulsifying dispersant used,
Generally, 40-60% of the total amount of water used is good. After the phase inversion is completed, the remaining water at a temperature lower than the softening point of the tackifying resin is added at a stretch, diluted and cooled quickly, and the particle size of the emulsion particles is set so that fusion and aggregation do not occur. By completing the emulsification while maintaining the above, a good emulsion having a uniform particle size can be obtained. Hot water below the softening point can be added to the molten resin above the softening point of the petroleum resin to cause phase inversion, but from the W / O type until the phase inversion to the O / W type emulsion, Is a preferable method for obtaining a uniform particle size and a stable emulsion.

It goes without saying that the emulsifying and dispersing agent represented by the general formula (1) is effective for a petroleum resin having a relatively low softening point or a petroleum resin which is almost liquid at normal temperature even under normal pressure.

In the present emulsification process, an alkali, an amine such as caustic soda, caustic potash,
Monoethanolamine, morpholine, triethanolamine, etc., as well as sequestering agents, thickeners, protective colloid agents,
A rust preventive, an antiseptic (mold) agent, and the like can be used, and a better and stable O / W type emulsion of petroleum resin at the time of production can be produced.

The O / W aqueous emulsion of the petroleum resin thus obtained has a solid content concentration of usually 40 to 70% by weight, preferably 50 to 65% by weight, and a viscosity of about several tens to several thousand CPS. The particle size of the emulsion is usually about 0.1 to 0.5 μm.

The O / W type aqueous emulsion of the petroleum resin thus obtained is usually used in an amount of 10 to 200% by weight depending on the use of various adhesive base polymers (water dispersions) such as natural rubber latex, acrylic emulsion and synthetic rubber latex. By adding such parts, good adhesives can be adjusted. Hereinafter, examples of the present invention will be described. In the examples, parts,%
All are parts by weight and% by weight unless otherwise specified.

〔Example〕

[Synthesis Examples of Emulsifying Dispersants] Emulsifying Dispersants 1 to 5 Using the arylphenols of Synthesis Examples 7 to 8, emulsifying dispersants shown in Nos. 1 to 5 in Table 1 were synthesized and adjusted by a conventional method. The average number of moles of alkylene oxide added to 1 mole of allylphenol and the number of sulfates are the average number in one molecule.

Emulsifying and dispersing agent 6-7 Phenol 188 was added to a glass reactor equipped with a stirrer, thermometer, dropping device, inert gas introducing device, and condenser.
And 6 parts of 98% sulfuric acid, and the mixture was stirred uniformly, and a styrene monomer was dropped and reacted over 1 hour so as to maintain the temperature at 90 to 95 ° C. Next, 6 parts of 35% hydrochloric acid aqueous solution and 30 parts of paraformaldehyde were added and reacted at 90 to 95 ° C. for 24 hours, neutralized with caustic soda, washed with warm water and dehydrated, and then heated to 40 ° C.
Gave 620 parts of a black-brown solid allylphenol. The average molecular weight of this allylphenol having an average of two OH groups in the molecule was 630. Using this allylphenol, No. 4 and No. 5 emulsifying and dispersing agents shown in Table 1 were prepared.

The average number of moles of alkylene oxide added to allylphenol and the number of sulfate esters are the average number of additions in one molecule.

Emulsions shown in the following Examples were obtained using the allylphenols of Synthesis Examples 1 to 10.

Example 1 An autoclave equipped with a stirrer, a thermometer, a safety valve, an opening line, and a press-fitting device was charged with 570 parts of petroleum resin (manufactured by Toho Chemical Industry Co., Ltd., high resin # 90, softening point 100 ° C).
170 ℃ Kept. 2 parts of triethanolamine was pressurized, stirred for 10 minutes, and kept at 160 ° C. Then, while maintaining the temperature at 160 ° C., 120 gr of emulsifying dispersant No. 1 was press-injected and stirred for 10 minutes. Then 140 ° C
20 parts of hot water is gradually pressed in over 20 minutes, and creamy W /
An O-type emulsion was obtained. While maintaining the temperature in the bath at 160 ° C,
When 80 parts of 0 ° C hot water was gradually injected over 20 minutes,
The emulsion thickened and the emulsion turned into an O / W type. Subsequently, after 210 parts of hot water at 140 ° C. was injected in 2 minutes, the mixture was rapidly cooled to 30 ° C. or lower and filtered through a 200-mesh wire net to obtain a good aqueous emulsion of a tackifying resin. The yield of the obtained emulsion is 97%, the residual amount of 200 mesh wire mesh is 0.1%, and the solid content is
60%, average particle size was 0.3μ. The storage stability of this aqueous emulsion was good for 2 months or more, and the mixing stability with the acrylic emulsion and SBR latex was good.

The calculation of the yield, the remaining amount of filtration, and the like was performed by the following method.

Residual filtration amount (%): Percentage of residual resin on 200-mesh wire net to charged resin Average particle size: Measured with Coulter Counter N-4 particle size distribution device.

Storage stability: The obtained emulsion is left at room temperature and the number of days until water starts to separate on the surface. Mixing stability: (1) Acrylic emulsion (butyl acrylate / 2 ethylhexyl acrylate / acrylic acid = 95/2/3 (weight) Ratio), a mixture which does not produce coagulated material when mixed with acrylic emulsion / tackifying resin = 8/2 (solid content), The result was evaluated as x.

 The following Examples and Comparative Examples were similarly evaluated.

(2) SBR-latex (JSR0561, solid content 69%, pH = 1
0, manufactured by Japan Synthetic Rubber Co., Ltd.).

Examples 2-5 As in Example 1, various petroleum resins are listed in Table 1.
Aqueous emulsification was carried out using the emulsifying dispersant shown in (1). Table 2 shows the conditions of the emulsification and Table 3 shows the properties of the obtained aqueous emulsion.

Comparative Examples 1-3 As in Example 1, aqueous emulsification was performed on various petroleum resins using a known emulsifying dispersant. Table 2 shows the conditions of the emulsification, and Table 3 shows the properties of the obtained aqueous emulsion. In Comparative Example No. 2, when poly (8) oxyethylene nonyl phenyl ether (non-ionic) was used as an emulsifying dispersant, no emulsification was possible.

〔The invention's effect〕

From the examples and comparative examples in the present invention, the general formula ( The aqueous emulsion of tackifier resin produced by using the emulsion dispersion stabilizer shown in 1) has a fine particle diameter, and also has stability over time,
It can be seen that a polymer having good compatibility with the base polymer can be obtained.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-150425 (JP, A) JP-A-56-87421 (JP, A) JP-A-53-133259 (JP, A) JP-A-56- 38126 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08J 3/00-3/28 C08L 57/02

Claims (1)

(57) [Claims] 1. After forming a W / O type emulsion of a petroleum resin at a temperature higher than the softening point and a pressure higher than the atmospheric pressure, the petroleum resin is then subjected to a phase transition (phase inversion) to obtain a stable oil. / W-type emulsion, the following general formula as an emulsifying dispersant [However, X is -CH ₂ -, l is an integer of 1 or 2, R is —CH ₂ —CH ₂ — or m is an integer of 3 to ₁₀₀ , R ₁ is hydrogen or CH ₃ — or Y is hydrogen or -SO ₃ Z (Z is a monovalent or divalent cation, amine), however, Y is at least one of the n is SO ₃ Z,
n is 2 or an integer of 2 or more], wherein one or more of the compounds represented by the following formulas are used.