JPH02215802A - Production of decolored petroleum resin - Google Patents

Abstract

PURPOSE:To obtain the title resin more efficiently than in the case when other solvent is used by performing hydrogenation in a specified solvent when a petroleum resin is hydrogenated and decolored with a hydrogenation catalyst under H<2> pressure. CONSTITUTION:When a petroleum resin is hydrogenated and decolored with a hydrogenation catalyst under H2 pressure, the hydrogenation is performed by using methylcyclohexane and/or ethylcyclohexane as a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a decolorized petroleum resin, which is obtained by hydrogenating a petroleum resin.

More specifically, the present invention relates to a method for producing a decolorized petroleum resin, characterized in that hydrogen decolorization is efficiently carried out by using a solvent selected from methylcyclohexane and/or ethylcyclohexane during the hydrogenation reaction.

[Conventional technology]

Petroleum resins are produced by cationically polymerizing polymerizable compounds such as diolefins and monoolefins contained in cracked oil fractions obtained by thermal decomposition of petroleum in the presence of Friedel-Crafts catalysts. Alternatively, it can be produced by radical polymerization or thermal polymerization. These petroleum resins are functional resins with unique physical properties such as tackiness, adhesion, and compatibility with other resins, and are mixed with various resins, rubbers, and oil-based substances, and are used in paints, printing, inks, and traffic. It is used in a wide range of applications such as paints, adhesives, and adhesives.

Petroleum resins originally have a pale yellow or light brown hue.

It is well known that petroleum resins can be decolored by hydrogenating the unsaturated double bonds in their molecular skeletons, and can be used for disposable diapers that require transparency, hot melt adhesives for sanitary products, pressure-sensitive adhesives, and food packaging. Hydrogenated decolorized petroleum resins are preferably used as adhesives, modifiers for PP films, and the like, and demand in these fields has been on the rise in recent years.

Additionally, hydrogenated decolorized petroleum resins have the advantage of improved thermal stability and weather resistance.

[Problem to be solved by the invention]

However, the molecular weight of petroleum resin is 400 to too much.

degree and large, or 50 to 10 in petroleum resin.
Because it contains 00ppL1 of sulfur, which poisons the hydrogenation reaction catalyst, high temperatures and high temperatures are required to carry out the hydrogenation reaction.
Very harsh reaction conditions at high pressures generally have to be employed.

On the other hand, hydrogenation under mild reaction conditions at low temperature and low pressure requires the use of a large amount of catalyst or a long reaction time.

In the hydrogenation reaction of petroleum resins, ordinary saturated hydrocarbons such as cyclohexane, heptane, and hexane are generally used as solvents. Hydrogenation decolorization is difficult.

[Means for Solving the Problems] As a result of intensive study by the present inventors on a method capable of decolorizing a petroleum resin by a hydrogenation reaction under as mild reaction conditions and using a smaller amount of catalyst, surprisingly, The present inventors have discovered that the above-mentioned problems can be solved by carrying out the hydrogenation reaction in a specific solvent when a petroleum resin is hydrogenated and decolorized with a hydrogenation catalyst under hydrogen pressure, and the present invention has been completed.

That is, the present invention relates to the production of a decolorized petroleum resin, which is characterized in that when a petroleum resin is hydrogenated and decolorized with a hydrogenation catalyst under hydrogen pressure, the hydrogenation reaction is carried out in a solvent selected from methylcyclohexane and/or ethylcyclohexane. Regarding the method.

The reason why methylcyclohexane and/or ethylcyclohexane are particularly effective as a solvent in carrying out the method of the present invention is not clear, but it may be that the solubility of petroleum resin is different from other solvents, or that petroleum resin is The amount of sulfur contained has a very large effect on the hydrogenation reaction activity.
When the amount of sulfur increases, it becomes difficult for the hydrogenation reaction to proceed, so by using methylcyclohexane and/or ethylcyclohexane as a solvent, the sulfur contained in petroleum resin becomes more catalytic poison than other solvents. It is also possible that they are in a condition that makes it difficult for them to work.

In the present invention, petroleum resins include mainly C9 resins such as styrene, vinyltoluene, α-methylstyrene, and indene.
C9-based or aromatic petroleum resins obtained by copolymerizing fractions, C9-based or aromatic petroleum resins obtained by copolymerizing mainly C3 fractions, such as isoprene, piperylene, and 2-methylbutene-1 and 2.
It refers to a C8C9 petroleum resin obtained by copolymerizing a di- or aliphatic petroleum resin, a C9 fraction, and a C3 fraction.

In the present invention, the optimum amount of solvent in the hydrogenation reaction is preferably 0.3 to 3.0 times the weight of the petroleum resin.

If the amount is less than 0.3 times, the progress of the hydrogenation reaction will be slow and the hydrogenation rate will be difficult to increase.

Moreover, if the amount is more than 3.0 times, although the hydrogenation reaction will proceed, the cost for finally separating the hydrogenated resin from the solvent will increase.

If less than the same amount of solvent is used for the petroleum resin, the viscosity of the reaction liquid will become relatively high, so when separating the catalyst by filtration after the hydrogenation reaction, it is necessary to add a small amount of solvent to improve filtration performance. is possible.

- For boat fishing, the hue of petroleum resin is pale yellow to light brown with a Gardner color number of 4 to 12, but according to the method of the present invention, the hue of decolorized petroleum resin can be reduced to a Hazen color number of 250 or less. can.

(The hue of the petroleum resin was measured according to the Hazen color number method and the Gardner color number method of JIS K6901. A Hazen color number of 400 approximately corresponds to a Gardner color number of 1.) The degree of decolorization of the decolorized petroleum resin and the hydrogenation rate There is a relatively good correlation between them.

It varies depending on the type of petroleum resin used as the starting material, but in order to decolorize to a Hazen color number of 250 or less, at least 15
% or more is required.

Further decolorization can be achieved by increasing the hydrogenation rate. The hydrogenation rate can be arbitrarily adjusted by changing reaction conditions such as catalyst amount, hydrogen pressure, reaction temperature, and reaction time.

In particular, in order to increase the hydrogenation rate under mild reaction conditions, it is more preferable that the sulfur content in the petroleum resin is small.The petroleum resin contains about 50 to 11,000 pp of sulfur, but it is preferable. is preferably 150 ppm or less, more preferably 100 pp+w or less.

When the sulfur content in the petroleum resin is high, the sulfur content can be reduced by a known method and then subjected to a hydrogenation reaction.

The hydrogenation rate in the present invention refers to the rate at which unsaturated double bonds in the molecular skeleton of petroleum resin are hydrogenated, and is a value calculated from the measurement of the proton N)' IR spectrum using the following formula. .

Integral region Bi4 of saturated hydrocarbons from AiO to 4.0 ppm
．． 2-a, opp- integral region of unsaturated hydrocarbons As the hydrogenation catalyst in the present invention, any catalyst can be used as long as it has hydrogenation ability, and is not particularly limited. Any one can be used as long as it is used.

For example, nickel, palladium, rhodium,
Platinum metal catalysts such as platinum and ruthenium, or cobalt, iron, chromium, copper, zinc,
These include catalysts containing a mixture of one or more of alkali metals and alkaline earth metals, or supported catalysts in which these metals are supported on a carrier such as diatomaceous earth, carbon, silica, or alumina. A supported catalyst is used.

The type of hydrogenation reaction is not particularly limited and can be carried out by a conventional method. For example, there are a batch type suspended bed system, a flow type fixed bed system, etc.

Reaction conditions such as catalyst amount, hydrogen pressure, reaction temperature, and reaction time in the hydrogenation reaction should be determined depending on the type of petroleum resin, sulfur content, or properties of the target hydrogenated and decolorized petroleum resin, but in general, Catalyst amount is 0.1 to petroleum resin
35% by weight, hydrogen pressure of 5 to 250 kg/c+aG, reaction temperature of 100 to 270°61, and reaction time of 1 to 10 hours.

After the hydrogenation reaction is completed, the desired hydrogenated decolorized petroleum resin can be obtained by separating the catalyst by filtration and the solvent by distillation or the like.

According to the method of the present invention, petroleum resin can be efficiently decolorized by hydrogenation.

In other words, under the same hydrogenation reaction conditions, by using a solvent selected from methylcyclohexane and/or ethylcyclohexane, a higher hydrogenation rate can be achieved compared to other saturated hydrocarbon solvents.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but these are just examples and the present invention is not limited thereto.

Example 1 In a 200 d autoclave, 27 g of commercially available petroleum resin (Toho Kagaku type "HiResin #90" sulfur content 9399 m, hue Gardner color number 8) was mixed with 40 g of methyl cyclohexa.
After dissolving 0.27 g of stabilized nickel catalyst (N-113 catalyst manufactured by 8Hun Chemical Co., Ltd.) as a hydrogenation catalyst and purging the system with nitrogen gas, 100 kg/c4 of hydrogen was added.
Pressure was applied to G.

Temperature raised to 250'C in 20°C, total pressure 100kg/c+
The hydrogenation reaction was carried out at a dG temperature of 250°C for 5.5 hours.

After the reaction was completed, the catalyst was filtered off.

Methylcyclohexane was removed first at normal pressure and then under reduced pressure to obtain a hydrogenated petroleum resin.

The hydrogenation rate of the hydrogenated petroleum resin thus obtained was 67.2%.

The hue was Hazen color number 20 and was sufficiently bleached.

Example 2 A hydrogenated petroleum resin was obtained in the same manner as in Example 1 except that ethylcyclohexane was used instead of methylcyclohexane. The hydrogenation rate of this hydrogenated petroleum resin was 61.6%, and the 0 hue had a Hazen color number of 20, indicating that it was sufficiently decolored.

Comparative Example 1 A hydrogenated petroleum resin was obtained in the same manner as in Example 1 except that cyclohexane was used instead of methylcyclohexane.

The hydrogenation rate of this hydrogenated petroleum resin was 49.3%.

The hue was Hazen color number 40.

Comparative Example 2 A hydrogenated petroleum resin was obtained in the same manner as in Example 1, except that n-hebutane was used instead of methylcyclohexane.

The hydrogenation rate of this hydrogenated petroleum resin was 44.7%.

The hue was Hazen color number 40.

Example 3 In a 200 d autoclave, 20 g of a commercially available petroleum resin (Toho Kagakubu Hi-Resin 120SJ sulfur content 50 pp-1, hue Gardner color number 11) was mixed with ethylcyclohexane 5
Stabilized nickel (NN-113 manufactured by 8Koku Kagaku Co., Ltd.) 6 was added as a hydrogenation catalyst, and the system was heated with nitrogen gas ifW! After that, the pressure was increased to 10 kg/cjG with hydrogen.

In this state, the temperature was raised to 140℃, and the total pressure was 10kg/cdG.
.

The hydrogenation reaction was carried out at a temperature of 140"C for 6 hours.

After the reaction was completed, the catalyst was filtered off.

The ethylcyclohexane solvent was removed first at normal pressure and then under reduced pressure to obtain a hydrogenated petroleum resin.

The hydrogenation rate of the hydrogenated petroleum resin thus obtained was 37.1%.

The hue was Hazen color number 60.

Comparative Example 3 A hydrogenated petroleum resin was obtained in the same manner as in Example 3, except that dioxane was used instead of ethylcyclohexane.

The hydrogenation rate of the hydrogenated petroleum resin was 16.2%.

The hue was Hazen color number 250.

Example 4 In a 200 d autoclave, a commercially available petroleum resin (Toho Chemical Co., Ltd. “Hi-Resin #90” with a sulfur content of 1100 pp.
, hue Gardner color number 8) was dissolved in 40 g of methylcyclohexane, and Pd (5χ
) 6.3 g of activated carbon-supported catalyst (containing water content 50.3x, manufactured by 8Ki Kagaku Co., Ltd.) was charged, and after replacing the inside of the system with nitrogen gas, it was pressurized to 30 kg/cdG with hydrogen.

In this state, the temperature is raised to 170°C and the total pressure is 30kg/e+j
Hydrogenation reaction was carried out at a G temperature of 170° C. for 6 hours.

After the reaction was completed, the catalyst was filtered off.

The methylcyclohexane solvent was first removed at normal pressure and then under reduced pressure to obtain a hydrogenated petroleum resin.

The hydrogenation rate of the thus obtained hydrogenated petroleum resin was 62.0%, and the zero hue had a Hazen color number of 30.

Example 5.6 A hydrogenated petroleum resin was obtained in the same manner as in Example 1, except that 40 g of methylcyclohexane in Example 1 was changed to 27 g and 18 g of methylcyclohexane, respectively.

The hydrogenation rate of hydrogenated petroleum resin is 64.3% and 5%, respectively.
It was 1.2%.

The hues were Hazen color numbers 30 and 40, respectively.

〔Effect of the invention〕

It is clear from the Examples and Comparative Examples that according to the present invention, a decolorized petroleum resin can be obtained more efficiently than when using other solvents.

Therefore, when producing a decolorized petroleum resin with the desired properties, it is possible to reduce the amount of catalyst and shorten the reaction time under the same reaction temperature and hydrogen pressure conditions, which is a huge improvement in production. be.

Patent applicant: Nippon Kayaku Co., Ltd.

Claims (1)

[Claims] 1. A method for producing a decolorized petroleum resin, which comprises carrying out the hydrogenation reaction in a solvent selected from methylcyclohexane and/or ethylcyclohexane when the petroleum resin is decolorized by hydrogenation using a hydrogenation catalyst under hydrogen pressure.