JPS6136005B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel method for producing a hydrocarbon resin, and more particularly, to a method for producing a hydrocarbon resin having good physical properties while preventing the formation of gel-like substances. Generally, hydrocarbon resins are unsaturated hydrocarbons having 4 to 10 carbon atoms, such as chain monoolefins such as butenes and pentenes, cyclic monoolefins such as cyclopentene and cyclohexene, 1,3-butadiene, 1,3-pentadiene, Polymerizing conjugated chain diolefins such as isoprene, conjugated cyclic diolefins such as cyclopentadiene, styrene, alkylstyrene, indene, alkylindene, dicyclopentadiene, etc. alone or in any combination in the presence of a Friedel-Crafts type catalyst, After the polymerization is stopped by a neutralization reaction, the catalyst is separated and removed, and the unreacted oil, the solvent used if necessary, and the oily product with a low degree of polymerization are removed by distillation. At this time, conjugated diolefins,
When indene, dicyclopentadiene, etc. are present in large amounts, gel-like substances that are insoluble in the solvent are likely to be produced as by-products, which not only makes it extremely difficult to separate and remove the catalyst, but also causes the gel-like substances to be mixed into the resulting resin. Efforts have been made to prevent gelling, as it has a negative impact on various applications. For example, in Japanese Patent Publication No. 34-5442, the heat 2
Raw materials whose content has been reduced to 2% or less through quantification are used, and U.S. Patent No. 2775575, No.
According to No. 2775526 and the like, a fraction of cracked oil from which cyclic diolefins are removed, and more preferably from which isoprene is removed, is used as a raw material. On the other hand, a method has also been developed for copolymerizing conjugated diolefins, which tend to produce gel-like by-products when polymerized alone, with appropriate mono-olefins to prevent gel-like by-products from occurring. . For example, Japanese Patent Publication No. 45-12306 describes a method of copolymerizing 1,3-pentadiene and 2-methyl-2-butene, and Japanese Patent Publication No. 47-1991 describes a method of copolymerizing 1,3-pentadiene, 1,3-butadiene, 2- Methyl-1-
A method for copolymerizing butene and 2-methyl-2-butene is disclosed. However, introducing a large amount of monoolefins into the feedstock oil increases the amount of by-product oily products, lowers the yield of resinous products, and lowers the softening point of the resulting resin. The present inventors have conducted extensive research to overcome the drawbacks of such known methods, and have found that even in the case of monomer compositions that tend to produce gel-like substances as by-products, there is no need to pre-treat the raw materials. In addition, we established a method for suppressing the formation of gel-like substances without introducing relatively large amounts of monoolefins into feedstock oil. The raw material applied to the present invention may be any unsaturated hydrocarbon having 4 to 10 carbon atoms and capable of cationic polymerization, but usually includes soft or heavy naphtha, kerosene or light oil fraction, heavy oil, or raw materials. Among the by-products obtained when producing ethylene, propylene, etc. through thermal cracking such as steam cracking, gas phase pyrolysis, sand cracking, etc. or catalytic cracking, the boiling point range of -7 to 280°C is It is a combination of unsaturated hydrocarbon fractions having 4 to 4 carbon atoms or fractions obtained by appropriately refining and separating them.
When a distillate containing at least 50% by weight of linear conjugated diolefins of No. 5, such as 1,3-butadiene, 1,3-pentadiene, isoprene, etc. in the monomer components, is used as a raw material, a pale yellow industrial grade Very useful resins are obtained in high yields and without gel by-products. In the present invention, such monomers are
When polymerizing in the presence of a Crafts type catalyst, the polymerization is carried out in the presence of sulfur monochloride or phosphorus trichloride. The amount of these compounds used is preferably 0.01 to 1.0 mol, more preferably 0.02 to 0.3 mol, per 1 mol of catalyst, and the amount of these additives added is 1.0 mol.
If the amount exceeds the molar amount, the yield of the resin produced tends to decrease and the softening point of the resin tends to decrease. Friedel-Crafts type catalysts used in the present invention typically include aluminum, boron, iron,
Examples include fluorides, chlorides, bromides and iodides of tin, titanium, etc., and among them, halides of aluminum or boron, particularly aluminum chloride or boron trifluoride are preferred. When carrying out a polymerization reaction, when the catalyst is solid, it is usually used in the form of particles having a size of 5 to 200 meshes, preferably 20 to 200 meshes. The amount of catalyst used is not particularly limited, but it needs to be used within a range that allows the polymerization reaction to be sufficiently carried out. Polymerization is usually carried out by adding the catalyst to the solvent and then gradually adding the monomers into the system, which facilitates control of the reaction temperature. Furthermore, it is preferable to add sulfur monochloride or phosphorus trichloride used in the present invention to the solvent before introducing the monomer into the solvent containing the catalyst, and add these additives to the polymerization system after the start of polymerization. If added, the inhibitory effect of the gel will be reduced. Diluents are usually used in polymerization reactions, preparation of catalysts and additives, etc., but such diluents are inert to the reaction, and include aromatic hydrocarbons such as benzene, toluene, xylene, pentane, hexane, etc. Representative examples include aliphatic hydrocarbons such as heptane and alicyclic hydrocarbons such as cyclohexane. However, when the content of conjugated diolefin in the monomer composition is large, a solvent containing 50% by weight or more of aromatic hydrocarbons may be used to further ensure the effect of suppressing the formation of gel-like substances. preferable. The solvent is usually 20 to 1000 parts by weight per 100 parts by weight of the polymerizable component.
It is used in proportions of 50 to 500 parts by weight, preferably 50 to 500 parts by weight. Polymerization is usually carried out at -20 to 100°C, preferably 0 to 80°C.
The pressure of the reaction system may be above or below atmospheric pressure. The reaction time is also not critical and can generally vary from a few seconds to a few hours. The polymer thus obtained is treated and dried according to conventional methods. The resin obtained by the present invention has a softening point of 60 to 150°C, even higher in some cases, although it varies depending on the main polymerization component in the monomer composition, and is generally aliphatic, aromatic or It is an industrially useful resin that is soluble in halogenated hydrocarbon solvents. In particular, the resins obtained by the present invention are characterized by a lower melt viscosity than resins obtained by conventional polymerization methods, which provides advantages in a variety of applications. It also has excellent compatibility with ethylene-vinyl acetate copolymers, which are widely used as the main component of hot melt adhesives. The present invention will be explained in more detail with reference to the following examples, but the present invention is not limited thereto. Note that parts and % used in the examples mean parts by weight and % by weight. Example 1 100 parts of benzene and 1 part of aluminum chloride were placed in a glass flask, a predetermined amount of sulfur monochloride was added, and the mixture was kept at 40°C and stirred for 10 minutes. Then the first
A feedstock containing a total of 83 parts of monomer having the composition shown in the table was gradually added continuously over 60 minutes. During the reaction, the temperature was maintained at 45℃, and after the addition of the raw material oil,
After stirring for another 30 minutes, methanol and 28%
The aluminum chloride was decomposed by adding an equal mixture of aqueous ammonia. Particles generated by decomposition are removed by filtration, and the liquid is transferred to a glass flask.
After heating while blowing nitrogen to distill and remove unreacted hydrocarbons and solvent, the temperature was raised to 230°C. Next, saturated steam was blown into the system to remove the low polymer produced by the polymerization reaction and the remaining solvent, and after confirming that almost no oil layer existed in the distillate, steam was blown into the system. The molten residue was taken out into an aluminum dish and allowed to cool, yielding a pale yellow resinous substance. Before neutralizing the polymerization reaction solution, it was passed through an 80-mesh stainless steel wire mesh, and the wire mesh was thoroughly washed with toluene, acetone, and hot water in that order, and the amount of gel-like material remaining on the wire mesh was measured. . The results are shown in Table 2.

【table】

[Table] Example 2 A reaction was carried out according to Example 1 except that a predetermined amount of phosphorus trichloride was used instead of sulfur monochloride. The results are shown in Table 3.

【table】

Claims (1)

[Claims] 1. When producing a hydrocarbon resin by cationically polymerizing an unsaturated hydrocarbon having 4 to 10 carbon atoms in the presence of a Friedel-Crafts type catalyst, in the presence of sulfur monochloride or phosphorus trichloride. A method for producing a hydrocarbon resin, characterized by carrying out polymerization. 2. The method according to claim 1, wherein the unsaturated hydrocarbon contains at least 50% by weight of a chain conjugated diene having 4 to 5 carbon atoms. 3. The method according to claim 1, wherein the amount of sulfur monochloride or phosphorus trichloride added is 0.01 to 1.0 mol per mol of catalyst. 4. The method according to claim 1, wherein the polymerization is carried out after previously contacting the catalyst with sulfur monochloride or phosphorus trichloride. 5. The method according to claim 1, wherein the catalyst is aluminum halide.