Preparation method of aromatic hydrocarbon modified high softening point hydrogenated petroleum resin
By adding a mixture of aromatic monomers and dicyclopentadiene dropwise at low temperature and combining it with a hydrogenation reaction, the problem of controlling the softening point and molecular weight of resin under high aromatic modification was solved, and a high softening point hydrogenated petroleum resin suitable for BOPP film was prepared.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NINGBO JINHAI CHENGUANG CHEM
- Filing Date
- 2023-04-10
- Publication Date
- 2026-05-22
AI Technical Summary
Existing technologies make it difficult to prepare dicyclopentadiene hydrogenated petroleum resins with high softening points and appropriate molecular weights under high aromatic content modification, resulting in dark resin color and excessive styrene self-polymerization, which makes it difficult to apply to the BOPP film field.
A mixture of aromatic monomers and dicyclopentadiene was added dropwise at low temperature, and the temperature was gradually increased. Combined with a hydrogenation reaction, the selectivity of phenylnorbornene was controlled, and aromatic modified high softening point hydrogenated petroleum resin was prepared through a multi-step reaction.
The prepared resin has a high softening point, a reasonable molecular weight distribution, and good color, making it suitable as a stiffening agent in the BOPP film field to improve film performance.
Abstract
Description
Technical Field
[0001] This invention belongs to the field of petroleum resin synthesis technology, specifically relating to a method for preparing aromatic-modified high-softening-point hydrogenated petroleum resin. Background Technology
[0002] With the construction of new ethylene plants and the maturation of C5 separation technology, the amount of dicyclopentadiene (DCPD) on the market is increasing. How to explore new application areas for dicyclopentadiene and increase its added value has attracted more and more attention.
[0003] Currently, domestic resin manufacturers generally use the thermal polymerization method to synthesize dicyclopentadiene petroleum resin, and then perform full hydrogenation to prepare dicyclopentadiene hydrogenated petroleum resin with good color, light odor, and excellent thermal stability. These resins generally have low softening points and are typically used in adhesives, often in combination with thermoplastic elastomers such as styrene-isoprene-styrene block copolymers (SIS) and styrene-butadiene-styrene block copolymers (SBS). Furthermore, to improve compatibility with ethylene-vinyl acetate copolymers (EVA) and synthetic rubber, some manufacturers introduce aromatic monomers during the synthesis of dicyclopentadiene petroleum resin, followed by selective hydrogenation to obtain dicyclopentadiene hydrogenated petroleum resin that retains its aromaticity. However, these resins are also mainly used in the adhesives field.
[0004] Studies have found that high-softening-point fully hydrogenated petroleum resins modified with high aromatic content can be used as stiffening agents in the field of biaxially oriented polypropylene (BOPP) films. The addition of high-softening-point fully hydrogenated petroleum resins can not only improve the elastic modulus of the film, enhance its heat shrinkage and transparency, and increase its barrier properties against water vapor and oxygen, but also lower the processing temperature during production and improve the extensibility and film-forming properties of polypropylene (PP). However, the introduction of a large amount of aromatic monomers can significantly reduce the resin's softening point, deepen its hue, and even generate large amounts of aromatic self-polymers. Therefore, methods for preparing high-aromatic-content modified high-softening-point fully hydrogenated petroleum resins are very rare.
[0005] US Patent Application No. US1793698, entitled "Thermopolymerization of Dicyclopentadiene / Vinyl Aromatic Resin" (Grant No. US6184308B1), discloses a method of blending dicyclopentadiene, aromatic monomers and solvents, followed by rapid heating to carry out a thermopolymerization reaction. The petroleum resin obtained by this method has a wide molecular weight distribution, a deep initial color, and a high melt viscosity.
[0006] US Patent Application No. US48700300, entitled "Copolymers and Methods for their Production" (Grant No. US6376630B1), discloses a method of slowly adding a mixture containing dicyclopentadiene and styrene to a high-temperature solvent (droplet addition method), followed by continued thermal polymerization after the addition is complete. The petroleum resin obtained by this method exhibits a significantly narrower molecular weight distribution, but the high-temperature droplet addition still results in a relatively high amount of styrene self-polymers.
[0007] US Patent Application No. US201515127813, entitled "Method for Production of Hydrogenated Petroleum Resin" (Grant No. US9994650B2), discloses a method of using a dropwise addition process to pre-react dicyclopentadiene and styrene monomers at 170–190°C, followed by a thermal polymerization reaction at an even higher temperature. This method can improve the selectivity of phenylnorbornene in the pre-reaction stage, but the styrene conversion rate is not high. It is foreseeable that if a higher softening point is desired, a longer high-temperature reaction time is required, and the remaining styrene monomer will still generate a large amount of styrene self-polymers during subsequent high-temperature reactions.
[0008] The above patents either generate a large amount of styrene self-polymers during high-temperature reactions, or make it difficult to obtain dicyclopentadiene hydrogenated petroleum resins with high softening points and appropriate molecular weights under the premise of high aromatic monomer addition. Summary of the Invention
[0009] The technical problem to be solved by the present invention is to provide a method for preparing aromatic modified high softening point hydrogenated petroleum resin in view of the current state of the prior art, so that it can be used as a stiffening agent in the field of BOPP film.
[0010] The technical solution adopted by this invention to solve the above-mentioned technical problems is as follows: a method for preparing aromatic modified high softening point hydrogenated petroleum resin, characterized by the following steps:
[0011] 1. Mix 5-50 wt% (preferably 10-30 wt%) of the total amount of dicyclopentadiene monomer with the polymerization solvent, heat to 130-210°C, and then start adding dropwise the mixture containing aromatic monomer and the remaining dicyclopentadiene monomer while adding dropwise and heating up. The addition time is 0.5-5 hours. When the addition is completed, the system temperature is 220-240°C.
[0012] The polymerization solvent comprises 10-50 wt% of the total amount of polymerization solvent, dicyclopentadiene monomer, and aromatic monomer, preferably 20-40 wt%; the aromatic monomer comprises 20-70 wt% of the total amount of dicyclopentadiene monomer and aromatic monomer, preferably 30-50 wt%.
[0013] 2. Continue heating to 250-350℃, and carry out the thermal polymerization reaction for 1-6 hours under 0-2.5MPa conditions to obtain the first reaction solution;
[0014] 3. The above first reaction solution is subjected to vacuum distillation at 150-250℃ and 0.1-10kPa for 1-3 hours to remove the polymerization solvent and unreacted monomers, and the basic polymer resin is obtained.
[0015] 4. Add the basic polymer resin and hydrogenation catalyst to the hydrogenation solvent and stir until homogeneous; wherein, the proportion of the hydrogenation solvent to the total amount of the hydrogenation solvent and the basic polymer resin is 30-80 wt%, preferably 40-60 wt%.
[0016] V. Under conditions of 150–300℃ and 3–10 MPa hydrogen pressure, hydrogenation reaction is carried out for 1–6 hours to obtain the second reaction solution;
[0017] 6. The above second reaction solution is distilled under reduced pressure at 180-280℃ and 0.1-10kPa for 1-3 hours to remove the hydrogenation solvent and some oligomers, thereby obtaining hydrogenated petroleum resin.
[0018] Preferably, the polymerization solvent is benzene, toluene, xylene, or trimethylbenzene. More preferably, the polymerization solvent is trimethylbenzene.
[0019] Preferably, the aromatic monomer is styrene, α-methylstyrene, or vinyltoluene. More preferably, the aromatic monomer is styrene.
[0020] Preferably, in step one, 5-50 wt% of the total amount of dicyclopentadiene monomer is mixed with the polymerization solvent and heated to 150-190°C; and the dropping time in step one is 1-3 hours.
[0021] Further, step two involves: continuing to heat to 260–300°C, and carrying out the thermal polymerization reaction for 2–5 hours under conditions of 0.5–2.0 MPa to obtain the first reaction solution.
[0022] The softening point of the base polymer resin is 90–140°C, preferably 110–130°C.
[0023] The hydrogenation solvent is cyclohexane, dimethylcyclohexane, solvent D40, or solvent D60. Solvent D40 is preferred.
[0024] The hydrogenation catalyst is a nickel-based, palladium-based, cobalt-based, or rhodium-based catalyst, preferably a nickel-based catalyst.
[0025] Further, step five involves: performing a hydrogenation reaction at 200–260°C and 5–8 MPa hydrogen pressure for 2–4 hours to obtain a second reaction solution.
[0026] In the above embodiments, preferably, the softening point of the hydrogenated petroleum resin is 120-170°C, more preferably 140-160°C.
[0027] Compared with existing technologies, the advantages of this invention are as follows: In the initial reaction system of step one, a portion of dicyclopentadiene is added, and the aromatic monomer is added dropwise at a lower temperature, increasing the selectivity of phenylnorbornene. Simultaneously, the temperature is increased while the mixture of aromatic monomer and dicyclopentadiene is added dropwise, which is beneficial for improving the yield of phenylnorbornene. This minimizes the formation of aromatic monomer self-polymers, and the softening point and molecular weight of the hydrogenated resin are easier to control, resulting in better color. The obtained aromatic-modified high-softening-point hydrogenated petroleum resin can be used as a stiffening agent in the BOPP film field.
[0028] Furthermore, considering the reaction mechanism, dicyclopentadiene first depolymerizes to form cyclopentadiene, which then undergoes a Diels-Alder reaction with the aromatic monomer to generate phenylnorbornene. To increase the selectivity of phenylnorbornene, a portion of dicyclopentadiene is added to the polymerization solvent beforehand, ensuring that there is a higher concentration of cyclopentadiene in the system during the dropwise addition of the aromatic monomer. Detailed Implementation
[0029] The present invention will be further described in detail below with reference to the embodiments.
[0030] Example 1:
[0031] Add 350g of trimethylbenzene and 115g of dicyclopentadiene to a 2L autoclave equipped with a stirrer. Purge the system with nitrogen 3–5 times. Then, heat to 180°C and begin uniformly adding a mixture of 463g of dicyclopentadiene and 473g of styrene dropwise while simultaneously increasing the temperature at a constant rate. The addition process takes 2 hours, and the system temperature reaches approximately 230°C when the addition is complete. Continue heating the reaction mixture to 280°C and react for another 4 hours (the pressure varies during the reaction; in the final stage, the pressure is around 1.0 MPa), yielding the first reaction solution.
[0032] The first reaction solution was distilled under reduced pressure for 2 hours at 200℃ and 5 kPaA (A represents absolute pressure, the same below) to remove the polymerization solvent tricresyl and unreacted monomers, yielding the basic polymer resin P1. The properties of resin P1 are shown in Table 1.
[0033] 500g of D40 solvent, 500g of basic polymer resin P1, and 15g of nickel-based hydrogenation catalyst were added to a 2L high-pressure reactor equipped with a stirrer. The system was then purged with nitrogen 3–5 times. The hydrogenation reaction was then carried out at 230℃ and 5MPa for 3 hours to obtain the second reaction solution.
[0034] The second reaction solution was distilled under reduced pressure at 230℃ and 5kPaA for 2 hours to remove the hydrogenation solvent (D40 solvent) and some oligomers, yielding hydrogenated petroleum resin H1. The properties of resin H1 are shown in Table 2.
[0035] Comparative Example 1:
[0036] Add 350g of trimethylbenzene, 578g of dicyclopentadiene, and 473g of styrene to a 2L autoclave equipped with a stirrer. Replace the system with nitrogen gas 3–5 times. Then heat to 280°C and react for 4 hours to obtain the polymerization reaction solution.
[0037] The polymerization reaction solution was distilled under reduced pressure at 200℃ and 5kPaA for 2 hours to remove the polymerization solvent tricresyl and unreacted monomers, yielding the basic polymer resin P2. The properties of resin P2 are shown in Table 1.
[0038] Add 500g of D40 solvent, 500g of basic polymer resin P2, and 15g of nickel-based hydrogenation catalyst to a 2L high-pressure reactor equipped with a stirrer. Replace the system with nitrogen gas 3-5 times. Then, hydrogenate the mixture for 3 hours at 230℃ and 5MPa to obtain the hydrogenation reaction solution.
[0039] The hydrogenation reaction solution was distilled under reduced pressure at 230℃ and 5kPaA for 2 hours to remove the hydrogenation solvent (D40 solvent) and some oligomers, yielding hydrogenated petroleum resin H2. The properties of resin H2 are shown in Table 2.
[0040] Comparative Example 2:
[0041] Add 350g of trimethylbenzene to a 2L autoclave equipped with a stirrer, and purge the system with nitrogen 3–5 times. Then raise the temperature to 240°C and begin uniformly adding a mixture of 578g of dicyclopentadiene and 473g of styrene dropwise. Maintain the system temperature at 240°C during the dropwise addition process, and continue the addition for 2 hours. After the dropwise addition is complete, raise the temperature of the reaction solution to 280°C and continue the reaction for 4 hours to obtain the polymerization reaction solution.
[0042] The polymerization reaction solution was distilled under reduced pressure at 200℃ and 5kPaA for 2 hours to remove the polymerization solvent tricresyl and unreacted monomers, yielding the basic polymer resin P3. The properties of resin P3 are shown in Table 1.
[0043] Add 500g of D40 solvent, 500g of basic polymer resin P3, and 15g of nickel-based hydrogenation catalyst to a 2L high-pressure reactor equipped with a stirrer. Replace the system with nitrogen gas 3–5 times. Then, hydrogenate the mixture for 3 hours at 230℃ and 5MPa to obtain the hydrogenation reaction solution.
[0044] The hydrogenation reaction solution was distilled under reduced pressure at 230℃ and 5kPaA for 2 hours to remove the hydrogenation solvent (D40 solvent) and some oligomers, yielding hydrogenated petroleum resin H3. The properties of resin H3 are shown in Table 2.
[0045] Comparative Example 3:
[0046] Add 350g of trimethylbenzene and 115g of dicyclopentadiene to a 2L autoclave equipped with a stirrer, and purge the system with nitrogen 3–5 times. Then raise the temperature to 180°C and begin uniformly adding a mixture of 463g of dicyclopentadiene and 473g of styrene dropwise, maintaining the system temperature at 180°C for 2 hours. After the addition is complete, raise the temperature of the reaction solution to 280°C and continue the reaction for 4 hours to obtain the polymerization reaction solution.
[0047] The obtained polymerization reaction solution was distilled under reduced pressure at 200℃ and 5kPaA for 2 hours to remove the polymerization solvent tricresyl and unreacted monomers, yielding the basic polymer resin P4. The properties of resin P4 are shown in Table 1.
[0048] Add 500g of D40 solvent, 500g of basic polymer resin P4, and 15g of nickel-based hydrogenation catalyst to a 2L high-pressure reactor equipped with a stirrer. Replace the system with nitrogen gas 3–5 times. Then, perform a hydrogenation reaction at 230℃ and 5MPa for 3 hours to obtain the hydrogenation reaction solution.
[0049] The hydrogenation reaction solution was distilled under reduced pressure at 230℃ and 5kPaA for 2 hours to remove the hydrogenation solvent (D40 solvent) and some oligomers, yielding hydrogenated petroleum resin H4. The properties of resin H4 are shown in Table 2.
[0050] Example 2:
[0051] Add 350g of trimethylbenzene and 137g of dicyclopentadiene to a 2L autoclave equipped with a stirrer. Purge the system with nitrogen 3–5 times. Then, raise the temperature to 170°C and begin uniformly adding a mixture of 546g of dicyclopentadiene and 368g of styrene dropwise while simultaneously raising the temperature at a constant rate. The addition process takes 2 hours. When the addition is complete, the system temperature reaches approximately 230°C. After the addition is complete, raise the temperature of the reaction mixture to 270°C and continue the reaction for 3 hours to obtain the first reaction solution.
[0052] The first reaction solution was distilled under reduced pressure at 200℃ and 5kPaA for 2 hours to remove the polymerization solvent tricresyl and unreacted monomers, yielding the basic polymer resin P5. The properties of resin P5 are shown in Table 1.
[0053] 500g of D40 solvent, 500g of basic polymer resin P5, and 15g of nickel-based hydrogenation catalyst were added to a 2L autoclave equipped with a stirrer. The system was then purged with nitrogen 3–5 times. The hydrogenation reaction was then carried out at 230℃ and 5MPa for 3 hours to obtain the second reaction solution.
[0054] The second reaction solution was distilled under reduced pressure at 230℃ and 5kPaA for 2 hours to remove the hydrogenation solvent (D40 solvent) and some oligomers, yielding hydrogenated petroleum resin H5. The properties of resin H5 are shown in Table 2.
[0055] Table 1
[0056] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 2 Basic polymer resin P1 P2 P3 P4 P5 DCPD / St (mass ratio) 55 / 45 55 / 45 55 / 45 55 / 45 65 / 35 Softening point, ℃ 123.0 115.0 120.0 113.0 124.0 Mz 3602 7809 4613 4509 3225 Mw / Mn 2.5 4.2 2.9 2.8 2.5 Chromaticity, G 11.9 13.0 12.6 12.0 10.4
[0057] Table 2
[0058] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Example 2 Hydrogenated resin H1 H2 H3 H4 H5 Softening point, ℃ 143.5 135.0 139.7 133.0 141.5 Mz 3070 6900 4007 3944 2700 Mw / Mn 2.3 3.5 2.6 2.5 2.3 Yellow Index, YI 0.8 2.6 1.9 1.5 0.6
[0059] As shown in Examples 1-2 and Comparative Examples 1-3, according to the manufacturing method of the present invention, the obtained base polymer resin and hydrogenated petroleum resin have higher softening points, smaller Mz, smaller Mw / Mn, and lighter color of the hydrogenated resin.
[0060] Therefore, according to the manufacturing method of the present invention, an aromatic modified high softening point hydrogenated petroleum resin can be prepared and used in the field of BOPP film.
[0061] Example 3:
[0062] A method for preparing aromatic-modified hydrogenated petroleum resin with a high softening point includes the following steps:
[0063] 1. Mix 5 wt% of the total amount of dicyclopentadiene monomer with the polymerization solvent (toluene), heat to 130°C, and then start adding dropwise the mixture containing aromatic monomer (vinyltoluene) and the remaining dicyclopentadiene monomer while adding dropwise and heating. The addition time is 5 hours. When the addition is completed, the system temperature is 240°C.
[0064] Of these, the polymer solvent accounts for 50 wt% of the total amount of polymerization solvent, dicyclopentadiene monomer, and aromatic monomer; and the aromatic monomer accounts for 20 wt% of the total amount of dicyclopentadiene monomer and aromatic monomer.
[0065] 2. Continue heating to 250℃ and carry out the thermal polymerization reaction for 6 hours (during the reaction, the pressure changes, and in the final reaction stage, the pressure is around 1.0 MPa) to obtain the first reaction solution;
[0066] 3. The first reaction solution was distilled under reduced pressure at 150℃ and 10kPa for 3 hours to remove the polymerization solvent and unreacted monomers, and the basic polymer resin was obtained.
[0067] IV. Add the basic polymer resin and hydrogenation catalyst (palladium-based hydrogenation catalyst) to the hydrogenation solvent (cyclohexane) and stir until homogeneous; wherein, the hydrogenation solvent accounts for 80 wt% of the total amount of hydrogenation solvent and basic polymer resin.
[0068] V. The second reaction solution was obtained by hydrogenation reaction at 150℃ and 10MPa hydrogen pressure for 6 hours.
[0069] 6. The second reaction solution was distilled under reduced pressure at 180℃ and 0.1kPa for 3 hours to remove the hydrogenation solvent and some oligomers, thus obtaining hydrogenated petroleum resin.
[0070] Example 4:
[0071] A method for preparing aromatic-modified hydrogenated petroleum resin with a high softening point includes the following steps:
[0072] 1. Mix 50wt% of the total amount of dicyclopentadiene monomer with the polymerization solvent (benzene), heat to 210℃, and then start adding dropwise the mixture containing aromatic monomer (α-methylstyrene) and the remaining dicyclopentadiene monomer while adding dropwise and heating. The addition time is 0.5h. When the addition is completed, the system temperature is 230℃.
[0073] Of these, the polymer solvent accounted for 10 wt% of the total amount of polymerization solvent, dicyclopentadiene monomer, and aromatic monomer; and the aromatic monomer accounted for 70 wt% of the total amount of dicyclopentadiene monomer and aromatic monomer.
[0074] 2. Continue heating to 350℃ and carry out the thermal polymerization reaction for 1 hour (during the reaction, the pressure changes, and in the final reaction stage, the pressure is around 1.0 MPa) to obtain the first reaction solution;
[0075] 3. The first reaction solution was distilled under reduced pressure at 250℃ and 0.1kPa for 1 hour to remove the polymerization solvent and unreacted monomers, and the basic polymer resin was obtained.
[0076] 4. Add the basic polymer resin and hydrogenation catalyst (cobalt-based hydrogenation catalyst) to the hydrogenation solvent (dimethylcyclohexane) and stir until homogeneous; wherein, the hydrogenation solvent accounts for 30 wt% of the total amount of hydrogenation solvent and basic polymer resin.
[0077] V. Under conditions of 300℃ and 3MPa hydrogen pressure, hydrogenation reaction was carried out for 1 hour to obtain the second reaction solution;
[0078] 6. The second reaction solution was distilled under reduced pressure at 280℃ and 10kPa for 1 hour to remove the hydrogenation solvent and some oligomers, thus obtaining hydrogenated petroleum resin.
[0079] Similarly, the hydrogenated petroleum resins prepared in Examples 3 and 4 can be used in the field of BOPP film.
Claims
1. A method for preparing aromatic-modified high-softening-point hydrogenated petroleum resin, characterized in that... The steps are as follows:
1. Mix 5-50 wt% of the total amount of dicyclopentadiene monomer with the polymerization solvent, heat to 130-210℃, and then start adding dropwise the mixture containing aromatic monomer and the remaining dicyclopentadiene monomer while heating. The addition time is 0.5-5 hours. When the addition is completed, the system temperature is 220-240℃. The polymerization solvent comprises 10–50 wt% of the total amount of polymerization solvent, dicyclopentadiene monomer, and aromatic monomer; the aromatic monomer comprises 20–70 wt% of the total amount of dicyclopentadiene monomer and aromatic monomer.
2. Continue heating to 250-350℃, and carry out the thermal polymerization reaction for 1-6 hours under 0-2.5MPa conditions to obtain the first reaction solution; 3. The above first reaction solution is subjected to vacuum distillation at 150-250℃ and 0.1-10kPa for 1-3 hours to remove the polymerization solvent and unreacted monomers, and the basic polymer resin is obtained.
4. Add the basic polymer resin and hydrogenation catalyst to the hydrogenation solvent and stir until homogeneous; wherein, the hydrogenation solvent accounts for 30-80 wt% of the total amount of hydrogenation solvent and basic polymer resin. V. Under conditions of 150–300℃ and 3–10 MPa hydrogen pressure, hydrogenation reaction is carried out for 1–6 hours to obtain the second reaction solution; 6. The above second reaction solution is distilled under reduced pressure at 180-280℃ and 0.1-10kPa for 1-3 hours to remove the hydrogenation solvent and some oligomers, to obtain hydrogenated petroleum resin; The aromatic monomer is styrene, α-methylstyrene, or vinyltoluene.
2. The preparation method according to claim 1, characterized in that: The polymerization solvent is benzene, toluene, xylene, or trimethylbenzene.
3. The preparation method according to claim 1, characterized in that: In step one, 5-50 wt% of the total amount of dicyclopentadiene monomer is mixed with the polymerization solvent and heated to 150-190°C; and the dropping time in step one is 1-3 hours.
4. The preparation method according to claim 1, characterized in that: Step two involves further heating to 260–300°C and carrying out a thermal polymerization reaction for 2–5 hours at 0.5–2.0 MPa to obtain the first reaction solution.
5. The preparation method according to claim 1, characterized in that: The softening point of the base polymer resin is 90–140°C.
6. The preparation method according to claim 1, characterized in that: The hydrogenation solvent is cyclohexane, dimethylcyclohexane, solvent D40, or solvent D60.
7. The preparation method according to claim 1, characterized in that: The hydrogenation catalyst is a nickel-based, palladium-based, cobalt-based, or rhodium-based catalyst.
8. The preparation method according to claim 1, characterized in that: Step five involves adding hydrogen at 200–260°C and 5–8 MPa hydrogen pressure for 2–4 hours to obtain the second reaction solution.
9. The preparation method according to any one of claims 1 to 7, characterized in that: The softening point of the hydrogenated petroleum resin is 120–170°C.