Production method for hydrogenated petroleum resin

Abstract

To provide a novel production method for a hydrogenated petroleum resin that does not cause filter clogging and is also capable of suppressing a significant decrease in catalytic activity in hydrogenation in a production method for a dicyclopentadiene/vinyl aromatic compound-based hydrogenated resin to be used as a tackifier. A production method for a dicyclopentadiene/vinyl aromatic compound-based hydrogenated petroleum resin, in which a reaction product obtained by reacting a dicyclopentadiene with a vinyl aromatic compound is subjected to thermal polymerization, thereby obtaining a thermal polymerization reaction product, followed by hydrogenation thereof, characterized in that as the thermal polymerization reaction product, an oligomer-removed thermal polymerization reaction product obtained by removing a dicyclopentadiene oligomer from the thermal polymerization reaction product is used as a hydrogenation raw material.

Claims

1. A method of producing a dicyclopentadiene/vinyl aromatic compound-based hydrogenated petroleum resin, the method comprising: subjecting a reaction product obtained by reacting a dicyclopentadiene with a vinyl aromatic compound to thermal polymerization, to obtain a thermal polymerization reaction product; and then hydrogenating the thermal polymerization reaction product, wherein, as the thermal polymerization reaction product, an oligomer-removed thermal polymerization reaction product is obtained by removing a dicyclopentadiene oligomer from the thermal polymerization reaction product and used as a hydrogenation raw material, and wherein the hydrogenation raw material is obtained by removing the dicyclopentadiene oligomer by contacting the dicyclopentadiene oligomer in the thermal polymerization reaction product with an adsorbent.

2. The method of claim 1, wherein the hydrogenation raw material is obtained by cooling the thermal polymerization reaction product to 10 to 40° C., to obtain a deposited material, and removing the dicyclopentadiene oligomer by performing solid-liquid separation of the deposited material.

3. The method of claim 1, wherein the adsorbent is at least one type selected from the group consisting of an activated clay, a silica gel, a silica-alumina, an activated alumina, an activated carbon, a zeolite, and a diatomaceous earth.

4. The method of claim 1, wherein the hydrogenation raw material has a turbidity at 25° C. of 12 NTU or less.

5. The method of claim 1, wherein the hydrogenating uses a palladium-supported catalyst.

6. The method of claim 1, wherein the vinyl aromatic compound is a compound represented by formula (1): ##STR00003## wherein R.sup.1 is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group, and the reaction product is a material comprising a phenylnorbornene derivative represented by formula (2): ##STR00004## wherein R.sup.1 is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group.

7. The method of claim 1, wherein the adsorbent comprises activated clay, a silica gel, a silica-alumina, an activated alumina, an activated carbon, a zeolite, a diatomaceous earth, or a mixture of two or more of any of these.

8. A method of producing a dicyclopentadiene/vinyl aromatic compound-based hydrogenated petroleum resin, the method comprising: subjecting a reaction product obtained by reacting a dicyclopentadiene with a vinyl aromatic compound to thermal polymerization, to obtain a thermal polymerization reaction product; and then hydrogenating the thermal polymerization reaction product, wherein, as the thermal polymerization reaction product, an oligomer-removed thermal polymerization reaction product is obtained by removing a dicyclopentadiene oligomer from the thermal polymerization reaction product and used as a hydrogenation raw material, and wherein the vinyl aromatic compound is of formula (1): ##STR00005## wherein R.sup.1 is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group, and wherein the reaction product comprises a phenylnorbornene of formula (2): ##STR00006## wherein R.sup.1 is a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group.

9. The method of claim 8, wherein the hydrogenation raw material is obtained by cooling the thermal polymerization reaction product to a temperature in a range of from 10 to 40° C., to obtain a deposited material, and removing the dicyclopentadiene oligomer by performing solid-liquid separation of the deposited material.

10. The method of claim 8, wherein the adsorbent is at least one type selected from the group consisting of an activated clay, a silica gel, a silica-alumina, an activated alumina, an activated carbon, a zeolite, and a diatomaceous earth.

11. The method of claim 8, wherein the adsorbent comprises activated clay, a silica gel, a silica-alumina, an activated alumina, an activated carbon, a zeolite, a diatomaceous earth, or a mixture of two or more of any of these.

12. The method of claim 8, wherein, in the phenylnorbornene of formula (2), R.sup.1 is a hydrogen atom.

13. The method of claim 8, wherein, in the phenylnorbornene of formula (2), R.sup.1 is an alkyl group.

14. The method of claim 8, wherein, in the phenylnorbornene of formula (2), R.sup.1 is a cycloalkyl group.

15. The method of claim 8, wherein, in the phenylnorbornene of formula (2), R.sup.1 is a cycloalkyl group.

16. The method of claim 8, wherein, in the phenylnorbornene of formula (2), R.sup.1 is an aryl group.

17. The method of claim 8, wherein, in the phenylnorbornene of formula (2), R.sup.1 is an aralkyl group.

18. The method of claim 8, wherein the hydrogenation raw material has a turbidity at 25° C. of 12 NTU or less.

19. The method of claim 8, wherein the hydrogenating uses a palladium-supported catalyst.

20. The method of claim 8, wherein the adsorbent comprises an activated alumina.

Description

EXAMPLES

(1) Hereinafter, the present invention will be more specifically described with reference to Examples, however, the present invention is not limited thereto. Note that in Examples, compositions and the like are on a mass basis unless otherwise specified.

(2) The physical properties and the like of the obtained resin were determined by the following methods.

(3) (1) Molecular Weight Measurement

(4) A molecular weight (a weight average molecular weight Mw, a number average molecular weight Mn, and a Z-average molecular weight Mz) and a molecular weight distribution (Mw/Mn) were determined as a polystyrene equivalent value using a high-speed GPC apparatus (HLC-8320GPC, manufactured by Tosoh Corporation) [eluent: tetrahydrofuran, column: G4000HXL, G3000HXL, and G2000HXL (two columns) manufactured by Tosoh Corporation were connected in series and used, detector: RI, standard sample: polystyrene].

(5) (2) Turbidity Measurement

(6) In turbidity measurement, a turbidity meter (2100N) manufactured by HACH was used, and the measurement was performed by a 90-degree scattered light detector, a transmitted light detector, and a forward scattered light detector for tungsten lamp light. A calibration curve was created from a formazin standard liquid, and as a relative turbidity, a sample was converted to a turbidity in NTU unit. Further, as a pretreatment for the measurement sample, the DCPD oligomer was sufficiently deposited by cooling for 13 hours or more in a refrigerator at 8° C., and thereafter, the sample was maintained in a thermostat bath at 25° C. for 1 hour or more, and the turbidity was measured.

(7) (3) Calculation Method for Catalytic Activity Decreasing Rate

(8) By using a fixed bed flow-type continuous reactor, a first-stage hydrogenation reaction was carried out under the following conditions: a raw material having a resin concentration of 15 mass %, a temperature of 120° C., a pressure of 0.5 MPa, and a palladium-based catalyst. Specifically, a sample was collected at an outlet of the reactor every time the liquid was allowed to pass therethrough, a residual olefin concentration in the sample was measured by .sup.1H-NMR, and a change in the residual olefin concentration with respect to the passing liquid amount was followed, whereby the catalytic activity decreasing rate was calculated. At this time, the residual olefin concentration in the sample was determined as follows. The collected sample was evaporated at 180° C. to remove the solvent and adjusted to 10 mass % with a deuterated chloroform solvent, thereafter .sup.1H-NMR was measured, and a peak corresponding to hydrogen of the olefin moiety was calculated as area %.

(9) Subsequently, the passing resin liquid amount per catalyst volume [t-resin/m.sup.3-cat] was expressed on the horizontal axis and the concentration of the peak corresponding to the olefin measured by .sup.1H-NMR [.sup.1H-NMR area %] (residual olefin concentration) was expressed on the vertical axis, and a slope thereof was calculated as the catalytic activity decreasing rate [d(.sup.1H-NMR area %)/d(t-resin/m.sup.3-cat)].

(10) Here, when a decrease in catalytic activity occurs every time the liquid is allowed to pass therethrough, an olefin remains without being hydrogenated, and therefore, the value of the residual olefin is increased, and it is indicated that as the numerical value is larger, the catalyst is more likely to be deteriorated. It is found that the catalyst deterioration rate is high when the increment of the numerical value becomes large.

Example 1: Production Example of Hydrogenated Petroleum Resin (1)

(11) <Solid-Liquid Separation by Natural Sedimentation>

(12) (Preliminary Reaction and Thermal Polymerization)

(13) In an autoclave having an internal volume of 10 L and equipped with a stirrer, 3600 g of a dicyclopentadiene fraction (concentration: 71 mass %) was charged, and the inside of the reaction system was replaced with nitrogen. Thereafter, the temperature was increased to 180° C. at a rate of 4° C./min while stirring at 500 rpm. A mixed solution of 1014 g of styrene and 986 g of the dicyclopentadiene fraction was added dropwise thereto over 2 hours in a state where the temperature was maintained at 180° C. After completion of the drop addition, the temperature was increased to 260° C. at a rate of 1.8° C./min. Thereafter, heating was continued at 260° C. for 92 minutes to perform a thermal polymerization reaction. By doing this, a thermal polymerization reaction product was obtained. The molecular weight of the resin at this time was Mz=1850 and Mw/Mn=2.26.

(14) The thermal polymerization reaction product was treated using a rotary evaporator for 10 minutes at a temperature of 230° C. under a nitrogen gas stream, whereby an unreacted monomer was removed. Subsequently, a treatment was performed for 15 minutes at a temperature of 230° C. and a pressure of 6.7 kPaA (A represents an absolute pressure, and the same applies hereinafter), whereby a part of the low molecular weight material was removed.

(15) (Removal of DCPD Oligomer by Solid-Liquid Separation through Natural Sedimentation)

(16) The above-mentioned thermal polymerization reaction product was diluted to a concentration of 15.0 mass % by adding dimethylcyclohexane (hereinafter referred to as “DMCH”) thereto. This diluted solution was cooled to a temperature of 25° C. to deposit a DCPD oligomer, and further left to stand overnight so as to allow the DCPD oligomer to naturally sediment, and a supernatant portion was separated and recovered and used as a hydrogenation raw material. The turbidity of this hydrogenation raw material at 25° C. was 0.56 NTU.

(17) (Hydrogenation Step)

(18) By using the above-mentioned hydrogenation raw material, two-stage continuous hydrogenation with a palladium-based catalyst was performed, whereby a hydrogenated petroleum resin was obtained. That is, the raw material as liquid was allowed to pass through a fixed bed flow reactor (gas-liquid co-current flow, downflow type) filled with a palladium-supported alumina catalyst, and a hydrogenation reaction was performed at a temperature of 120° C., a hydrogen pressure of 0.5 MPaG, and an LHSV of 17 [h.sup.−1]. Further, by using the same fixed bed flow reactor, a hydrogenation reaction was performed at a temperature of 170° C., a hydrogen pressure of 0.5 MPaG, and an LHSV of 17 [h.sup.−1].

(19) After the hydrogenation reaction, this reaction liquid was taken out, and a treatment was performed using a rotary evaporator for 20 minutes at a temperature of 180° C. under a nitrogen gas stream, whereby the solvent was removed. Subsequently, a treatment was performed for 10 minutes at a temperature of 180° C. and a pressure of 6.7 kPaA, whereby a part of the low molecular weight material was removed.

(20) (Catalytic Activity Decreasing Rate)

(21) In the first-stage hydrogenation step, the residual olefin concentration when the passing resin liquid amount was 22.7 [t-resin/m.sup.3-cat] was calculated to be 3.84 [.sup.1H-NMR area %] and the residual olefin concentration when the passing resin liquid amount was 192.5 [t-resin/m.sup.3-cat] was calculated to be 4.06 [.sup.1H-NMR area %]. From these, the catalytic activity decreasing rate was estimated to be 0.0012 [(.sup.1H-NMR area %)/(t-resin/m.sup.3-cat)]. The results are shown in the below-mentioned Table 1.

Comparative Example 1: Production Example of Hydrogenated Petroleum Resin (2)

(22) A hydrogenated petroleum resin was produced in the same manner as in Example 1 except that the DCPD oligomer was not removed. Incidentally, the turbidity of the thermal polymerization reaction product was 24.0 NTU.

(23) (Catalytic Activity Decreasing Rate)

(24) In a step corresponding to the first-stage hydrogenation step in Example 1, the residual olefin concentration when the passing resin liquid amount was 21.5 [t-resin/m.sup.3-cat] was calculated to be 2.63 [.sup.1H-NMR area %] and the residual olefin concentration when the passing resin liquid amount was 118.7 [t-resin/m.sup.3-cat] was calculated to be 2.88 [.sup.1H-NMR area %]. From these, the catalytic activity decreasing rate was estimated to be 0.0026 [(.sup.1H-NMR area %)/(t-resin/m.sup.3-cat)]. The results are shown in the below-mentioned Table 1.

Example 2: Production Example of Hydrogenated Petroleum Resin (3)

(25) <Solid-Liquid Separation by Centrifugal Sedimentation>

(26) A hydrogenated petroleum resin was produced in the same manner as in Example 1 except that the following solid-liquid separation by centrifugal sedimentation was performed as the method for removing the DCPD oligomer.

(27) (Removal of DCPD Oligomer by Solid-Liquid Separation through Centrifugal Sedimentation)

(28) A solution obtained by diluting the thermal polymerization reaction product to a concentration of 15.0 mass % by adding DMCH thereto was cooled to a temperature of 25° C. to deposit a DCPD oligomer, and treated with a centrifugal sedimentation separator (a plate-type centrifugal separator: ADS-250MS (number of revolutions: 10000 rpm) manufactured by Saito Separator Limited) at a flow rate of 600 g/min to perform solid-liquid separation. A clear liquid obtained at this time was recovered and used as a hydrogenation raw material. The turbidity of the hydrogenation raw material at 25° C. was 10.0 NTU.

(29) (Catalytic Activity Decreasing Rate)

(30) In a step corresponding to the first-stage hydrogenation step in Example 1, the residual olefin concentration when the passing resin liquid amount was 22.7 [t-resin/m.sup.3-cat] was calculated to be 3.76 [.sup.1H-NMR area %] and the residual olefin concentration when the passing resin liquid amount was 281.7 [t-resin/m.sup.3-cat] was calculated to be 4.18 [.sup.1H-NMR area %]. From these, the catalytic activity decreasing rate was estimated to be 0.0015 [(.sup.1H-NMR area %)/(t-resin/m.sup.3-cat)]. The results are shown in the below-mentioned Table 1.

Example 3: Production Example of Hydrogenated Petroleum Resin (4)

(31) <Solid-Liquid Separation by Filtration>

(32) A hydrogenated petroleum resin was produced in the same manner as in Example 1 except that the following solid-liquid separation by filtration was performed as the method for removing the DCPD oligomer.

(33) (Removal of DCPD Oligomer by Solid-Liquid Separation Through Filtration)

(34) A solution obtained by diluting the thermal polymerization reaction product to a concentration of 15.0 mass % by adding DMCH thereto was cooled to a temperature of 25° C. to deposit a DCPD oligomer. A dried celite aid was mixed therein, and the resulting mixture was applied to a 360-mesh wire net, and the diluted solution was allowed to pass therethrough, whereby the DCPD oligomer was separated by filtration. A filtrate obtained at this time was recovered and used as a hydrogenation raw material. The turbidity of the hydrogenation raw material at 25° C. was 0.97 NTU. The results are shown in the below-mentioned Table 1.

Example 4: Production Example of Hydrogenated Petroleum Resin (5)

(35) <Adsorption>

(36) A hydrogenated petroleum resin was produced in the same manner as in Example 1 except that an adsorbent was used as the method for removing the DCPD oligomer.

(37) (Removal of DCPD Oligomer by Adsorption)

(38) A solution obtained by diluting the thermal polymerization reaction product to a concentration of 15.0 mass % by adding DMCH thereto was allowed to pass through spherical activated alumina in a particulate form with a size of 2 to 4 mm (KHD-24, manufactured by Sumika Alchem Co., Ltd.) at an LHSV of 2.0 [h.sup.−1] using a fixed bed flow reactor. The temperature and the pressure in an adsorption tower at this time were 120° C. and 0.5 MPa, respectively. The obtained adsorbed liquid after allowing the solution to pass therethrough was recovered and used as a hydrogenation raw material. The turbidity of the hydrogenation raw material at 25° C. was 7.4 NTU. The results are shown in the below-mentioned Table 1.

(39) TABLE-US-00001 TABLE 1 Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Method for Solid-liquid non Solid-liquid Solid-liquid Adsorption removing DCPD separation by separation by separation oligomer natural centrifugal by filtration sedimentation sedimentation Turbidity at 25° C. of 0.56 24.0 (thermal 10.0 0.97 7.4 hydrogenation raw polymerization material reaction (NTU) product) Catalytic activity 0.0012 0.0026 0.0015 — — decreasing rate (.sup.1H-NMR area %)/ (t-resin/m.sup.3-cat)

(40) From the results of Example 1, it was confirmed that when the removal of the DCPD oligomer is sufficient, the turbidity of the hydrogenation raw material is extremely low, the catalytic activity decreasing rate in the hydrogenation step is small, and efficient production of the hydrogenated petroleum resin can be performed. Further, from the results of Comparative Example 1, when the DCPD oligomer is not removed, the turbidity of the thermal polymerization reaction product is 24.0 NTU, which is extremely high, the catalytic activity decreasing rate in the hydrogenation step is high, and a decrease in catalytic activity is likely to occur, and therefore, it was determined that efficient production cannot be performed.

(41) From the results of Example 2, it was confirmed that even when the turbidity of the hydrogenation raw material is a little higher than that of Example 1, the catalytic activity decreasing rate in the hydrogenation step is substantially equal to that of Example 1. Further, from the results of Example 3 and Example 4, it was confirmed that the method for removing the DCPD oligomer by solid-liquid separation through filtration or using an adsorbent is also an effective means. In addition, it was revealed that when the hydrogenation raw materials obtained in Example 1 to Example 4 were used, filter clogging can be avoided.

INDUSTRIAL APPLICABILITY

(42) According to the method of the present invention, by removing a DCPD oligomer from a thermal polymerization reaction product obtained by thermal polymerization of a reaction product of a dicyclopentadiene and a vinyl aromatic compound, filter clogging is not caused in the production step thereafter, and also a decrease in catalytic activity in the hydrogenation step can be suppressed. Therefore, the present invention is useful as a method for industrially advantageously producing a dicyclopentadiene/vinyl aromatic compound-based hydrogenated petroleum resin having favorable physical properties as a tackifier.