JPH0339527B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to hydrocarbon resins. More specifically, the present invention relates to a novel hydrocarbon resin that exhibits low melt viscosity, excellent compatibility with base polymers for pressure-sensitive adhesives and adhesives, and good hue. [Problems to be solved by conventional technology/inventions] Conventionally, pressure sensitive adhesives, hot melt adhesives,
It is known that rosin resins, alkyd resins, epoxy resins, etc. can be used as tackifiers (tackifiers) including adhesive raw materials in the fields of paints, traffic paints, etc. Among these, rosin resins are the most popular, but because these resins rely on natural products as raw materials, they cannot meet the remarkable growth in demand in recent years. Therefore, recently, various petroleum-based hydrocarbon resins have been developed to replace it. Incidentally, in recent hot melt adhesives, the need for low melt viscosity tackifiers has been avoided due to the need to improve working speed and maintain a uniform coating amount. However, the styrene resins and cycloalkene resins conventionally used for this purpose generally exhibit high melt viscosity, and many exhibit a pungent odor when heated and melted. The latter is also inferior in hue. For example, Japanese Patent Application Laid-open No. 1983-
42610 proposes a copolymer of a linear unsaturated hydrocarbon and/or a cyclic hydrocarbon having a vinylidene group and 9,10-dihydrodicyclopentadiene. Although this proposal satisfies the melt viscosity and odor, the hydrocarbon resin obtained by the above proposal sometimes has a yellowish tinge, so when this resin is used as a tackifier, it is difficult to adhere to the adhesive. There remained the problem that the commercial value of the drug could be impaired. [Summary of the Invention] The present inventors have made extensive efforts to develop a hydrocarbon resin that exhibits low melt viscosity, excellent compatibility with adhesives and adhesive base polymers, and has good hue, heat resistance stability, and odor. As a result of investigation, it was discovered that a specific new hydrocarbon resin obtained from a styrenic hydrocarbon and a cycloalkene satisfies the above requirements, and the present invention was completed. That is, the present invention provides a copolymer consisting essentially of a styrenic hydrocarbon (A) and a cycloalkene (B), wherein the proportion of polymerized units of (A) is about 50 to about 99 mol%, and (B) The proportion of polymerized units is about 1 to about 50 mol%
Copolymerize in the range of [total of (A) and (B) is 100 mol%],
A hydrocarbon resin (C) with a number average molecular weight in the range of about 200 to about 10,000 is defined as a material invention, and a monomer mixture consisting essentially of a styrenic hydrocarbon (A) and a cycloalkene (B) is free. A method for producing the hydrocarbon resin (C) characterized by polymerization in the presence of a Dell-Crafts type catalyst is defined as a production invention, and the hydrocarbon resin (C) is further used for hot melt adhesives or pressure sensitive adhesives. Tatsuki Fire is a usage invention. Each invention of the present application will be explained in detail below. [Hydrocarbon resin] Specifically, the styrenic hydrocarbon (A) forming the hydrocarbon resin (C) according to the present invention includes, for example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene. , p-methylstyrene,
Examples include m-isopropenyltoluene and p-isopropenyltoluene. Each of these may form a hydrocarbon resin (C) together with the cycloalkene (B) described below, or two or more components may form a hydrocarbon resin (C) together with the cycloalkene (B) in any proportion. It may be formed. Further, the cycloalkene (B), which is another component forming the hydrocarbon resin (C), specifically includes cyclohexene, cyclopentene, cycloheptene, cyclooctene, cyclononene, etc., as well as hydrogen atoms in these rings. Examples include those in which one or more of the following is substituted with a lower alkyl group such as a methyl group, ethyl group, propyl group, or isopropyl group. Each of these cycloalkenes (B) may form a hydrocarbon resin (C) together with the styrenic hydrocarbon (A), or two or more components may form a hydrocarbon resin (C) together with the cycloalkene (B) in any proportion. A hydrocarbon resin (C) may be formed. The proportion of polymerized units of the above-mentioned styrenic hydrocarbon (A) and cycloalkene (B) contained in the hydrocarbon resin (C) according to the present invention is about 50 to 99 mol% for (A) and about 99% by mole for (B). 1
(The total of (A) and (B) is 100 mol%. The same applies hereinafter.) Preferably, (A) is about 60 to 98 mol%, and (B) is about 2 to 40 mol%, more preferably about 70 to 95 mol% of (A) and about 5 to 30 mol% of (B). If (A) exceeds the required range of polymerization unit ratios above, the melt viscosity will increase and the compatibility with the base polymer of the adhesive or adhesive will deteriorate; If the amount of (A) is less than that, the molecular weight will be low and odor will be generated during heating, which is not preferable. In addition, it is preferable that the constituent components of the hydrocarbon resin (C) are only styrene hydrocarbon (A) and cycloalkene (B), but these (A), In addition to component (B), alkenes such as pentene-2, 2-methyl-2-butene, butene-2, etc.
mol% or less, butadiene, isoprene, 1,
10 mol% of alkadienes such as 3-pentadiene
It does not matter if it is a constituent component below. The hydrocarbon resin (C) according to the present invention needs to have a number average molecular weight in the range of about 200 to 10,000, preferably in the range of about 300 to 700. Note that the number average molecular weight is a value converted to polystyrene using the GPC method. In addition, the hydrocarbon resin (C) is generally below 200°C, preferably about 150°C.
It has the following softening points (ring and ball method according to JIS K-2531), including those that are liquid at room temperature, approximately 10,000 CPS or less,
It preferably has a melt viscosity of about 200 CPS or less (Emiller viscometer, resin temperature 200°C), and has a molecular weight expressed as the ratio of weight average molecular weight (Mw) (measured in the same manner as Mn) to Mn, Mw/Mn. the distribution has about 1.0 to 5.0, preferably about 1.0 to 3.0, and
The hue according to the Gardner method (ASTM D 1544-68) is 3 or less. When the hydrocarbon resin (C) of the present invention is used as a tackifier as described below, the resin has properties required for a tackifier, such as a low melt viscosity and excellent compatibility with the base polymer. In addition, it also has a good hue. [Production method of hydrocarbon resin] Next, the production method invention of the present application will be explained. The catalyst used in the polymerization of the copolymer according to the present invention is generally known as a Friedel-Crafts catalyst, and includes, for example, aluminum chloride, aluminum bromide, dichloromonoethylaluminum, titanium tetrachloride, and tetrachloride. Examples include various complexes of tin, boron trifluoride, and boron trifluoride. The amount of catalyst used is preferably in the range of 0.01 to 5.0 weight (%), and 0.05 to 5.0% by weight, based on the total of component (A) and component (B).
A range of 3.0% by weight is particularly preferred. During polymerization, it is preferable to use a polymerization solvent in order to remove reaction heat and suppress the viscosity of the polymerization solution. Suitable solvents include the above-mentioned cycloalkene (B) itself, which is a polymerization component, as well as aromatic hydrocarbons such as toluene, xylene, ethylbenzene, mesitylene, cumene, and cymene, or mixtures thereof, or mixtures thereof with pentane or hexane. , aliphatic hydrocarbons such as heptane and octane, and/or mixtures with alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclohexane. When the cycloalkene (B) itself is used as a solvent, it is preferable that the concentration of the above-mentioned styrenic hydrocarbon (A), which is another comonomer, is about 20 to 80% by weight. When using other solvents, the other solvents are added to the mixture of (A) and (B) adjusted to the above concentration, and the initial concentration of the total polymerization of components (A) and (B) is usually 30 to 30%. 70 weight (%)
It is preferably 40 to 60 weight (%), and more preferably 40 to 60 weight (%). The polymerization may be carried out either batchwise or continuously, and it is also possible to carry out multistage polymerization. In either method, the initial polymerization concentrations of component (A) and component (B) are preferably carried out within the above-mentioned ranges. Although it is preferable that the raw material monomers (A) and (B) are pure, they may contain polymerization components as described above as long as the effects of the present invention are not impaired. The polymerization temperature varies depending on the proportions of component (A) and component (B) used, the type and amount of the catalyst, and the type and amount of the solvent, but it is usually preferably carried out in the range of -20 to 60°C. The polymerization time is selected in the range of 0.5 to 5 hours, but the polymerization is usually almost completed in 1 to 2 hours. After the polymerization is completed, the catalyst is decomposed with an aqueous alkali solution or methanol, washed with water, and unreacted monomers, solvents, etc. are distilled off to obtain the desired resin. The component composition of the copolymer that is the hydrocarbon resin (C) according to the present invention can be adjusted by adjusting the proportions of the component monomers (A) and (B) and the above conditions. The number average molecular weight (Mn) and molecular weight distribution (w/n) of the copolymer of the present invention can generally be adjusted as follows. That is, if the polymerization temperature is lowered, n of the copolymer increases, and conversely, if the polymerization temperature is raised, n becomes smaller. When cycloalkene (B) and other hydrocarbon solvents are used as solvents to increase the molar ratio (A)/(B) of the raw material monomers,
The Mn of the copolymer increases, and when the molar ratio (A)/(B) of the same raw material monomers is lowered, the Mn of the copolymer decreases. Further, when the concentration of the Friedel-Crafts catalyst is decreased, n of the copolymer increases, and when the concentration of the catalyst is increased, n of the copolymer decreases.
Among the three conditions mentioned above, by conducting the polymerization under conditions where the concentration of Friedel-Crafts catalyst and the raw material monomer molar ratio (A)/(B) are relatively low, w/
A copolymer with Mn of 1.1 to 2.5 can be easily obtained. Adjustment of the softening point can be achieved relatively easily by changing the polymerization temperature. In other words, if the polymerization temperature is lowered, the softening point of the resulting resin will be higher.
Conversely, if the polymerization temperature is raised, the softening point of the resin will be lowered, so if the polymerization temperature is appropriately selected after determining the raw material composition, type and amount of catalyst, and type and amount of solvent, the softening point of the resin produced can be lowered. can be adjusted to the desired range. [Use invention] Next, a use invention will be explained. The hydrocarbon resin (C) according to the present invention has excellent properties as a tackifier (tackifier) for hot melt adhesives, pressure sensitive adhesives, and the like. Adhesive compositions generally include hot melt adhesives, which are made by blending a base resin such as ethylene/vinyl acetate copolymer with a tackifier and, if necessary, wax and other additives, as well as natural rubber, synthetic rubber, etc. There are pressure-sensitive adhesives that are made of a base resin mixed with a tackifier and, if necessary, a solvent and other additives. The former hot melt adhesive is generally used as an adhesive or coating agent in fields such as bookbinding, can manufacturing, woodworking, laminating, sealing, and coating processing. The latter pressure-sensitive adhesive is generally coated on a base material such as paper, cloth, or plastic film for use in adhesive tapes, labels, and the like. In each of these adhesive compositions, a tackifier is blended with the base resin. In particular, in the case of hot melt adhesives, in addition to compatibility with the base resin such as ethylene/vinyl acetate copolymer and wax, adhesiveness, melt viscosity, and flexibility, heat stability, light stability, hue, etc. Good things are required. On the other hand, in the case of tackifiers for pressure-sensitive adhesives,
It must have excellent compatibility with base resins such as natural rubber and synthetic rubber, it must have good solubility in solvents, it must be chemically stable and have excellent weather resistance, and it has a good hue. It is required to have properties such as not having a strong odor. When the hydrocarbon resin (C) according to the present invention is used as a tackifier in a pressure-sensitive adhesive, examples of the base resin include natural rubber, styrene-butadiene copolymer rubber, polybutadiene, and Rubber-like products such as isoprolene, polyisobutylene, butyl rubber, polychloroprene, ethylene/propylene copolymer rubber, ethylene/propylene/diene copolymer rubber, styrene/butadiene/styrene block copolymer, styrene/isoprene/styrene block copolymer, etc. Polymers are used. In addition, when used as a hot melt adhesive, specific base resins include, for example,
Ethylene/vinyl acetate copolymer, polyethylene,
Polypropylene, ethylene/propylene copolymer, ethylene/acrylic acid copolymer, polyester, polyamide, polyvinyl acetate, etc. are used. In the case of hot melt adhesive compositions, it is particularly preferred to use an ethylene/vinyl acetate copolymer as the base resin. When the hydrocarbon resin according to the present invention is used as a tackifier, the blending ratio with the base resin varies somewhat depending on the hot melt adhesive composition and the pressure sensitive adhesive composition. In the case of hot melt adhesive compositions, the blending ratio of the tackifier is usually 20 to 300 parts by weight, preferably 20 to 300 parts by weight, based on 100 parts by weight of the base resin.
The amount ranges from 30 to 200 parts by weight, and in the case of pressure-sensitive adhesives, it usually ranges from 20 to 200 parts by weight, preferably from 30 to 150 parts by weight, based on 100 parts by weight of the base resin. In addition to the essential components of the tackifier and the base resin, various additives may be added to the adhesive composition using the hydrocarbon resin (C) according to the present invention, if necessary. For example, in the case of a hot melt adhesive composition, plasticizers such as dioctyl phthalate and dibutyl phthalate, waxes such as petroleum-based paraffin waxes with melting points of about 40 to 65°C, polyolefin waxes, microwaxes, and phenols are used. or bisphenol-based organic compounds,
Examples include antioxidants such as metal soaps. Also,
In the case of pressure-sensitive adhesive compositions, dioctyl phthalate, dibutyl phthalate, machine oil, process oil, plasticizers such as polybutene, fillers such as calcium carbonate, zinc white, titanium oxide, silica, amines, ketone-amines, etc. Examples include antioxidants, stabilizers, and phenol-based antioxidants.
The blending ratio of these additives is arbitrary and appropriate. The method for preparing an adhesive composition using the hydrocarbon resin (C) according to the present invention differs depending on whether it is a hot melt adhesive composition or a pressure sensitive adhesive. A method for preparing a hot melt adhesive composition is to heat and melt a mixture consisting of a hydrocarbon resin (C) as a tackifier, the base resin, and, if necessary, the various additives described above, and stir the mixture to form a uniform adhesive composition. A molten liquid is prepared and shaped into granules, flakes, pellets, rods, etc. depending on the purpose while cooling. This hot melt adhesive composition is melted again and used for adhesion or coating purposes. For example, when used for bonding purposes, a rod-shaped compound is used to bond corners of molded products by filling it into a welding gun. On the other hand, as a method for preparing pressure sensitive adhesives,
Hydrocarbon resin according to the invention as tackifier
(C) can be prepared by a conventional method such as kneading a mixture of the base resin and, if necessary, the various additives described above on a roll or dissolving it in a suitable solvent. When a hot melt adhesive composition is used as an adhesive or a coating agent in an adhesive composition using the hydrocarbon resin (C) according to the present invention, the hydrocarbon resin (C) according to the present invention is different from the base resin. The hot melt composition has excellent compatibility, heat stability, color and odor, so a uniform hot melt composition can be obtained. It has the advantage of not having a pleasant odor. Furthermore, even if the hydrocarbon resin of the present invention is used in a pressure-sensitive adhesive composition, the hydrocarbon resin as a tackifier has excellent weather resistance in addition to the above-mentioned characteristics, so that a uniform pressure-sensitive adhesive composition can be obtained. This pressure-sensitive adhesive composition has the advantage of being excellent in color and weather resistance, and having little odor. Adhesive compositions using the hydrocarbon resin of the present invention will be specifically explained later with reference to Examples. In addition,
In Examples, hydrocarbon resins were evaluated by the following method. (1) Softening point JIS K-5665 (2) Hue ASTM D 1544-58T (3) Heat resistance stability Take 5 g of hydrocarbon resin in a test tube (inner diameter 16 mm) and place it in a constant temperature bath kept at 200℃ for 30 minutes. After soaking for a period of time, the color was expressed by the method of ASTM D 1544-58T. (4) Odor The odor during heating and melting (200°C) was divided into three grades: A, B, and C, ranging from weak odor to strongly irritating odor. (5) Cloudy point: 140°F 2g of paraffin wax and hydrocarbon resin are placed in a test tube, melted in an oil bath temperature of 200°C, and mixed well. Set the thermometer so that the temperature sensitive part is located in the center of the melt, and allow it to cool at room temperature. The temperature when white clouds form is read as the cloudy point. (6) Melt viscosity at 200°C Measured with an Emiller rotational viscometer. (7) Number average molecular weight (Mn), molecular weight distribution (Mw/
Mn) Calculated based on polystyrene using gel permeation chromatography. [Embodiments of the invention] Example 1 In a 500 ml four-necked flask equipped with a stirrer, condenser, thermometer and rubber cap for catalyst injection, 50 g of freshly distilled styrene, cyclopentene 11
g and 39 g of toluene were added thereto, stirred under a nitrogen atmosphere, and kept at 5°C. To this, 0.3 g of boron trifluoride phenol complex salt was added through the rubber cap using a syringe while cooling to maintain the temperature at 50° C., and stirring was continued for 2 hours. At this point, gas chromatography analysis of the polymerization solution revealed that styrene was 99.8% and cyclopentene was 99.8%.
80.0% reaction was achieved, and toluene was not changed at all. The catalyst was analyzed with a 10% caustic soda aqueous solution, washed with water until neutral, and concentrated to obtain 57.8 g of a colorless and transparent hydrocarbon resin (corrected for the amount of sampling for gas chromatography analysis). Therefore, it can be seen that the conversion rate of the reaction monomer into resin is 98.5%, which is almost quantitative. Hydrocarbon resin has a softening point of 93.0℃ and a hue of 1.
Below, the melt viscosity was 65 cp, Mn was 667, and Mw/Mn was 2.2. Examples 2 to 5, 7, 9 to 10, Comparative Examples 1 to 3 Polymerization and post-treatment were carried out in the same manner as in Example 1 using the monomers and polymerization conditions listed in Table 1. The results are shown in Table 1. Example 6 Boiling point 36-44 of _C5 fraction after isoprene extraction
℃ fraction was used as a raw material for petroleum resin, and a cyclopentene fraction (boiling point 36-44°C) having the composition shown in Table 2 was recovered from the recovered unreacted fraction. Table 2 Composition of cyclopentene fraction (wt%) Cyclopentene 15.4 2-methyl-2-butene 1.6 1,3-pentadiene 2.2 Pentene-2 9.7 Isoprene 0.2 Alkanes (C ₅ , C ₆ , C ₇ ) 70.9 Total 100.0 Stirrer , 20 g of hexane in a 500 ml 4-neck flask equipped with a condenser, thermometer, and dropping funnel.
Add 0.8 g of anhydrous aluminum chloride powder, stir under nitrogen atmosphere, and keep at 30°C. A mixture of 50g of styrene and 50g of cyclopentene distillate was added to this mixture from the dropping funnel while cooling to maintain the temperature at 30°C, and gas chromatography analysis revealed that styrene was 99.9%.
%, cyclopentene was 30.5% and other unsaturated compounds were 34.0%. By decomposing the catalyst with methanol, washing with water to neutrality, and concentrating, 58.6 g of an almost colorless and transparent hydrocarbon resin (sample corrected for gas chromatography analysis) was obtained. Table 1 shows the physical properties of the hydrocarbon resin. Example 8 Styrene and the cyclopentene fraction listed in Table 2 were polymerized and post-treated in the same manner as in Example 1 under the conditions listed in Table 1. The results are shown in Table 1. Comparative Example 4 The composition of the 9,10-dihydrodicyclopentadiene-containing fraction obtained by partially hydrogenating the dicyclopentadiene fraction was as follows. Table 3 Composition of fraction containing 9,10-dihydrodicyclopentadiene (wt%) 9,10-dihydrodicyclopentadiene 79.1 Dicyclopentadiene 0.1 The main components are 2-isopropenyl-norbonane and 2-isopropylidenenorbonane. Dihydro-isoprene/cyclopentadiene codimer 5.5 Tetrahydrodicyclopentadiene 9.6 Other polymerization components 5.7 Total 100.0 Styrene and 9,10-dicyclopentadiene were polymerized and post-treated in the same manner as in Example 1 under the conditions listed in Table 1. did. The results are shown in Table 1.

【table】

【table】

[Table] * Unable to measure due to low yield Examples 11, 12, Comparative Examples 6 to 8 40 parts of the hydrocarbon resin listed in Table 3, 40 parts of ethylene-vinyl acetate copolymer (Evaflex 210 manufactured by Mitsui Polychemical Co., Ltd.), 140 parts °F paraffin wax 20
The mixture was melt-stirred for 1 hour at an oil bath temperature of 180°C. Next, the mixture was left to stand in an air oven at 180°C for 4 hours to examine whether phase separation occurred. The color and peel strength of adhesives that did not undergo phase separation were measured using the following methods. The results are shown in Table 4. (a) Color of adhesive The color of the adhesive at room temperature was evaluated as follows. A: white, B: light yellow, C: tan (b) Peel strength Apply adhesive to aluminum foil (50 microns thick) to a thickness of 15 microns, and heat seal the adhesive surfaces together (temperature 170°C, pressure 1 kg) /cm ² , time 1 second). Next, using an Instron universal testing machine,
The peel strength was determined by T-peeling at a temperature of 25° C. and a speed of 300 mm/min. The results are shown in Table 4.

[Table] * Unable to measure due to carrier separation

Claims (1)

[Scope of Claims] 1 A copolymer consisting essentially of a styrenic hydrocarbon (A) and a cycloalkene (B), wherein the proportion of polymerized units of (A) is about 50 to about 99 mol%, ( The proportion of polymerized units of B) is about 1 to about 50 mol% [the total of (A) and (B) is 100
mol%] and has a number average molecular weight in the range of about 200 to about 10,000.
(C). 2. A styrenic hydrocarbon (A) characterized in that a monomer mixture consisting essentially of a styrenic hydrocarbon (A) and a cycloalkene (B) is polymerized in the presence of a Friedel-Crafts type catalyst. A copolymer consisting essentially of cycloalkene (B), in which the proportion of polymerized units of (A) is about 50 to about 99 mol%, and the proportion of polymerized units of (B) is about 1 to about 50 mol% [ The sum of (A) and (B) is 100
hydrocarbon resin (C) which is copolymerized in the range of mol%] and has a number average molecular weight in the range of about 200 to about 10,000.
manufacturing method. 3 A copolymer consisting essentially of a styrenic hydrocarbon (A) and a cycloalkene (B), in which the proportion of polymerized units of (A) is about 50 to about 99 mol%, and the proportion of polymerized units of (B) is about 1 to about 50 mol% [total of (A) and (B) is 100
Hydrocarbon resin (C) copolymerized in the range of mol%] and with a number average molecular weight in the range of about 200 to about 10,000.
A tackifier for hot melt adhesives or pressure sensitive adhesives consisting of: