A low softening point, high molecular weight C9 cold polymerization resin product and preparation method thereof

Abstract

The invention discloses a low softening point, high molecular weight C9 cold polymerization resin product and a preparation method thereof, and belongs to the technical field of petroleum resin preparation. The preparation method of the invention comprises the following steps: firstly, a C9 raw material is subjected to a depolymerization treatment in a high temperature depolymerization reactor, and then the depolymerized C9 raw material is subjected to a rectification treatment to remove light components and heavy components therein, and the raw material is divided into a styrene fraction and an indene fraction, and then the softening point and molecular weight of the C9 cold polymerization resin are adjusted by adjusting the ratio of the content of styrene and its derivatives and the content of indene and its derivatives in the raw material and the catalyst addition method, so as to prepare a resin product with a softening point of 85-120°C, a molecular weight of 2000-6000, and a Gardner color number of less than 8, thereby achieving controllable preparation of a C9 cold polymerization resin with a low softening point and a high molecular weight.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum resin preparation, and more specifically, relates to a low softening point, high molecular weight C9 cold polymerization resin product and a preparation method thereof. Background Art

[0002] C9 resin is a thermoplastic solid material prepared by using C9, a byproduct of ethylene cracking, as raw material. Its molecular weight is generally less than 2000 and its softening point is less than 150°C. The raw materials for cracking C9 are complex and can generally be divided into two categories. One category is active components such as styrene, methyl styrene, vinyl toluene, indene, dicyclopentadiene, etc., which can be polymerized in the presence of a catalyst to obtain a macromolecular resin product; the other category is inactive components such as alkylbenzenes and polycyclic aromatic hydrocarbons, which act as solvents in the polymerization reaction. Generally, the raw materials for cracking C9 contain about 50% active monomers and are rich in unsaturated olefins, which can be used to prepare C9 resin. Since C9 petroleum resin has the advantages of low acid value, good miscibility, water resistance, chemical resistance and ethanol resistance, its chemical properties are relatively stable and it is widely used in coatings, paints, rubber and other fields as a regulator and modifier to improve the performance of various products.

[0003] There are three commonly used methods for preparing C9 resin, namely thermal polymerization, catalytic polymerization, and free radical polymerization. Among them, catalytic polymerization is also called cationic polymerization. In the presence of a catalyst, the polymerizable monomers in the C9 raw material form carbon cations, which initiate chain polymerization to form petroleum resin. At present, the catalysts for producing petroleum resin are generally divided into two categories, one is a strong proton acid catalyst, such as H2SO4, HClO4, H3PO4, etc.; the other is Lewis acid, such as BF3, AlCl3, boron trifluoride ether complex, etc. At present, the most widely used catalysts in the industrial production of C9 resin are mainly BF3, AlCl3 and boron trifluoride ether complex. Catalytic polymerization has the advantages of low reaction temperature, fast reaction rate, high resin yield, lighter resin color and good quality. At present, catalytic polymerization is mostly used in China to prepare C9 resin.

[0004] Although the research on the production technology of C9 petroleum resin in my country started relatively late, and there is still a certain gap between the basic research and reaction mechanism research and those abroad, from the current C9 petroleum resin market, the domestic production technology level has been continuously developing in a state of continuous improvement. As of 2019, the domestic C9 petroleum resin production capacity is about 620,600 t / a, and the total production capacity of Henghe Materials C9 resin is about 115,000 t / a (including C9 hydrogenated petroleum resin), which is the largest enterprise in my country in terms of C9 resin production capacity; Qilong Group (including Shandong Qilong and Fushun Qilong) has a total production capacity of 80,000 t / a for C9 resin, ranking second; Luhua Hongjin C9 resin has a total designed production capacity of 47,600 t / a, ranking third. Although the output of C9 resin in China continues to increase, there are still some product quality problems, such as high softening point, low molecular weight, and poor application effect.

[0005] After searching, the Chinese patent application number is: 201910524465.X, the application date is: June 18, 2019, and the name of the invention is: A light-colored C9 cold-polymerized petroleum resin product and its preparation process. The application uses the C9 aromatic fraction or resin oil or a combination of the by-products of the cracking ethylene production unit as the main raw material, removes the heavier components and lighter components in the C9 raw oil, and then pre-polymerizes the raw oil to remove the components with higher reaction activity in the reaction raw materials; then the treated raw materials, indene and indane, styrene, methyl styrene and other substances are mixed, and their components are regulated to prepare light-colored resins with color numbers 2-5. Although the above application solves the color problem of the resin, the softening point of the resin is relatively high, between 115-135°C, and the molecular weight is relatively low, which limits its application. Summary of the invention

[0006] 1. Problem to be solved

[0007] The purpose of the present invention is to overcome the shortcomings of the C9 cold-polymerized petroleum resin product obtained by the existing process, which has a high softening point and a low molecular weight and is difficult to meet the use requirements, and provide a low softening point, high molecular weight C9 cold-polymerized resin product and a preparation method thereof. The technical solution of the present invention can effectively solve the above problems, prepare a C9 cold-polymerized resin with a softening point of 85-120°C, a molecular weight Mz of 2000-6000, and a Gardner color number of less than 8, which fully meets the use requirements of C9 resin in different fields.

[0008] 2. Technical solution

[0009] In order to solve the above problems, the technical solution adopted by the present invention is as follows:

[0010] A method for preparing a low softening point, high molecular weight C9 cold polymerization resin product of the present invention comprises the following steps:

[0011] Step 1, depolymerizing dicyclopentadiene in the C9 raw material into cyclopentadiene;

[0012] Step 2: distilling the depolymerized raw material to remove light components and heavy components, and dividing the depolymerized raw material into a styrene fraction and an indene fraction according to the boiling point of the intermediate component;

[0013] Step 3, mixing the styrene fraction, the indene fraction, styrene, indene and solvent oil to obtain a reaction raw material, and adding a catalyst to carry out a polymerization reaction;

[0014] Step 4: After the reaction is completed, the C9 cold polymerization resin polymerization liquid is obtained by alkali washing and water washing, and then the solvent, unreacted monomers and oligomers are removed by distillation, stripping and other methods to obtain C9 cold polymerization resin.

[0015] Furthermore, in step three, the polymerization temperature is 0-50° C., the polymerization time is 1-4 h, and the amount of catalyst added is 0.1-1 wt.%.

[0016] Furthermore, in step three, the catalyst is added in the following manner: first, a portion of the catalyst is added as a base, then the raw materials are added dropwise for polymerization reaction, and then the remaining catalyst is added during the reaction.

[0017] Furthermore, the initial amount of catalyst added is 10-100 wt.% of the total amount of catalyst added, and the remaining catalyst is added evenly in multiple times during the reaction, and the number of additions is controlled to be 0 to 7 times.

[0018] Furthermore, in step three, styrene and its derivatives in the reaction raw materials account for 15-50wt.% of the total amount of the reaction raw materials, indene and its derivatives account for 15-50wt.% of the total amount of the reaction raw materials, and the content of dicyclopentadiene is less than 2wt.%.

[0019] Furthermore, in step three, the catalyst is one or more of aluminum chloride, boron trifluoride ether complex, and boron trifluoride; the solvent oil is one or more of benzene, toluene, xylene, cyclohexane, and heptane.

[0020] Furthermore, in the distillation treatment in step 2, the light components removed mainly include cyclopentadiene, methylcyclopentadiene, dicyclopentadiene, and methyldicyclopentadiene; the heavy components removed mainly include naphthalene and other polycyclic aromatic hydrocarbons; wherein the amounts of the light components and heavy components removed account for 5-15wt.% and 10-20wt.% of the C9 raw material, respectively.

[0021] Furthermore, the main components of the styrene fraction separated in step 2 include styrene, methyl styrene, vinyl toluene, indene, and indane; among them, styrene and its derivatives account for 40-50wt.%, indene and its derivatives account for 10-20wt.%, and the content of dicyclopentadiene is less than 2wt.%.

[0022] Furthermore, in the indene fraction separated in step 2, the main components include indene, indane, methyl indene, methyl styrene, and vinyl toluene; among them, indene and its derivatives account for 40-50wt.%, styrene and its derivatives account for 10-20wt.%, and the content of dicyclopentadiene is less than 2wt.%.

[0023] The invention discloses a low softening point and high molecular weight C9 cold polymerization resin product, which is obtained by adopting the above preparation method, has a softening point of 85-120° C., a molecular weight of 2000-6000, and a Gardner color number of less than 8.

[0024] 3. Beneficial effects

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention discloses a method for preparing a C9 cold-polymerized resin product with a low softening point and a high molecular weight. The light components, heavy components and part of dicyclopentadiene of the C9 raw material are removed by depolymerization and distillation processes, and the C9 raw material is divided into a styrene fraction and an indene fraction according to different boiling points. The C9 fraction is then mixed with styrene, indene and solvent oil to undergo a polymerization reaction under the action of a catalyst, thereby preparing a C9 resin with a low softening point and a high molecular weight to meet the application requirements of different fields.

[0027] (2) The present invention provides a method for preparing a low softening point, high molecular weight C9 cold polymerization resin product. By adjusting the ratio of styrene and its derivatives to indene and its derivatives in the reaction raw materials, and setting the catalyst addition method and reaction parameters, the softening point, color number and molecular weight of the C9 resin can be regulated, thereby preparing a C9 resin with a softening point of 85-120°C, a molecular weight of 2000-6000, and a Gardner color number of less than 8, thereby broadening the application field of the C9 resin.

[0028] (3) The present invention provides a method for preparing a low softening point, high molecular weight C9 cold polymerization resin product, which optimizes the design of process parameters, especially controls the polymerization temperature, time and amount of catalyst added to ensure the concentration and activity of the catalyst during the reaction, thereby affecting the chain growth and chain transfer process of the cationic reaction, and further effectively regulating the softening point and molecular weight of the C9 cold polymerization resin.

[0029] (4) The low softening point, high molecular weight C9 cold polymerization resin product of the present invention can effectively reduce its softening point and increase its molecular weight by optimizing its preparation process. The softening point of the C9 cold polymerization resin product can be controlled at 85-120°C, the molecular weight can be adjusted at 2000-6000, and the Gardner color number is less than 8, thereby effectively meeting its use requirements in different fields. DETAILED DESCRIPTION

[0030] In view of the disadvantage that the C9 resin produced by the existing traditional preparation process has a high softening point and a low molecular weight, which limits its application scope, the present invention removes light components and heavy components in the raw material by depolymerization and distillation, and divides the depolymerized raw material into a styrene fraction and an indene fraction according to the boiling point of the intermediate component; and then adjusts the softening point and molecular weight of the C9 cold-polymerized resin by adjusting the ratio of the content of styrene and its derivatives and the content of indene and its derivatives in the raw material and the catalyst addition method, thereby achieving controllable preparation of C9 cold-polymerized resin with a low softening point and a high molecular weight.

[0031] Specifically, the light components removed mainly include cyclopentadiene, methylcyclopentadiene, dicyclopentadiene, and methyldicyclopentadiene, accounting for 5-15wt.% of the C9 raw material, and the heavy components mainly include naphthalene and other polycyclic aromatic hydrocarbons, accounting for 10-20wt.% of the C9 raw material. In the segmented styrene fraction, the main components include styrene, methyl styrene, vinyl toluene, indene, and indane; styrene and its derivatives account for 40-50wt.%, indene and its derivatives account for 10-20wt.%, and the content of dicyclopentadiene is less than 2wt.%. In the segmented indene fraction, the main components include indene, indane, methyl indene, methyl styrene, and vinyl toluene; among them, indene and its derivatives account for 40-50wt.%, styrene and its derivatives account for 10-20wt.%, and the content of dicyclopentadiene is less than 2wt.%. More optimally, during the catalytic reaction, the method of the present invention controls the reaction raw material ratio, reaction temperature, reaction time, the amount of catalyst added and its concentration during the reaction (mainly by regulating the catalyst addition method, that is, first adding a portion of the catalyst to keep the catalyst concentration at a large level at the beginning of the reaction, and then gradually adding the remaining catalyst evenly multiple times), thereby effectively controlling the chain growth and chain transfer process of the cationic reaction, and the softening point of the obtained C9 cold polymerization resin can be controlled at 85-120°C, the molecular weight at 2000-6000, and the Gardner color number is less than 8, thereby effectively meeting its use requirements in different fields. In addition, it should be noted that when the amount of catalyst added is relatively small, such as when the amount added accounts for 0.1wt.% of the reaction raw materials, it is no longer necessary to add it in stages, and all the catalysts can be directly added at one time.

[0032] The present invention is further described below in conjunction with specific embodiments.

[0033] Example 1

[0034] Accurately weigh a certain amount of styrene fraction, indene fraction, styrene, indene and solvent oil and mix them evenly. In the reaction raw materials, the content of styrene and its derivatives is 50wt.%, the content of indene and its derivatives is 15wt.%, and the content of other alkanes is 35wt.%. The amount of catalyst added accounts for 0.1% of the total mass of the reaction raw materials. The initial amount of catalyst added is 100wt.% of the total catalyst amount, the polymerization temperature is 30℃, and the reaction time is 1h. After polymerization, alkali washing, water washing, stripping and other processes, the prepared C9 resin has a softening point of 87.0℃, a molecular weight Mz of 2500, and a Gardner color number of 4.

[0035] Example 2

[0036] Accurately weigh a certain amount of styrene fraction, indene fraction, styrene, indene and solvent oil and mix them evenly. In the reaction raw materials, the content of styrene and its derivatives is 45wt.%, the content of indene and its derivatives is 22wt.%, and the content of other alkanes is 33wt.%. The amount of catalyst added accounts for 0.7% of the total mass of the raw materials. The initial amount of catalyst added is 40wt.% of the total catalyst amount, and the remaining catalyst is added on average, the number of additions is 5 times, the polymerization temperature is 10°C, and the reaction time is 4h. After polymerization, alkali washing, water washing, stripping and other processes, the prepared C9 resin has a softening point of 110.6°C, a molecular weight Mz of 5300, and a Gardner color number of 5.

[0037] Example 3

[0038] Accurately weigh a certain amount of styrene fraction, indene fraction, styrene, indene and solvent oil and mix them evenly. In the reaction raw materials, the content of styrene and its derivatives is 40wt.%, the content of indene and its derivatives is 30wt.%, and the content of other alkanes is 30wt.%. The amount of catalyst added accounts for 1.0% of the total mass of the raw materials. The initial amount of catalyst added is 50wt.% of the total catalyst amount, and the remaining catalyst is added on average, the number of additions is 5 times, the polymerization temperature is 50℃, and the reaction time is 1.5h. After polymerization, alkali washing, water washing, stripping and other processes, the prepared C9 resin has a softening point of 113.2℃, a molecular weight Mz of 3900, and a Gardner color number of 6.

[0039] Example 4

[0040] Accurately weigh a certain amount of styrene fraction, indene fraction, styrene, indene and solvent oil and mix them evenly. In the reaction raw materials, the content of styrene and its derivatives is 35wt.%, the content of indene and its derivatives is 35wt.%, and the content of other alkanes is 30wt.%. The amount of catalyst added accounts for 0.5% of the total mass of the raw materials. The initial amount of catalyst added is 60wt.% of the total catalyst amount, and the remaining catalyst is added on average, the number of additions is 4 times, the polymerization temperature is 40°C, and the reaction time is 2h. After polymerization, alkali washing, water washing, stripping and other processes, the prepared C9 resin has a softening point of 97.7°C, a molecular weight Mz of 4500, and a Gardner color number of 7.

[0041] Example 5

[0042] Accurately weigh a certain amount of styrene fraction, indene fraction, styrene, indene and solvent oil and mix them evenly. In the reaction raw materials, the content of styrene and its derivatives is 30wt.%, the content of indene and its derivatives is 35wt.%, and the content of other alkanes is 35wt.%. The amount of catalyst added accounts for 1.0% of the total mass of the raw materials. The initial amount of catalyst added is 10wt.% of the total catalyst amount, and the remaining catalyst is added on average, the number of additions is 7 times, the polymerization temperature is 5°C, and the reaction time is 2h. After polymerization, alkali washing, water washing, stripping and other processes, the prepared C9 resin has a softening point of 119.6°C, a molecular weight Mz of 6000, and a Gardner color number of 7.

[0043] Example 6

[0044] Accurately weigh a certain amount of styrene fraction, indene fraction, styrene, indene and solvent oil and mix them evenly. In the reaction raw materials, the content of styrene and its derivatives is 25wt.%, the content of indene and its derivatives is 30wt.%, and the content of other alkanes is 45wt.%. The amount of catalyst added accounts for 0.8% of the total mass of the raw materials. The initial amount of catalyst added is 80wt.% of the total catalyst amount, and the remaining catalyst is added on average, the number of additions is 2 times, the polymerization temperature is 0°C, and the reaction time is 2h. After polymerization, alkali washing, water washing, stripping and other processes, the prepared C9 resin has a softening point of 116.4°C, a molecular weight Mz of 3200, and a Gardner color number of 8.

Claims

1. A method for preparing a low softening point, high molecular weight C9 cold polymerization resin product, characterized in that: The steps include: Step 1, depolymerizing dicyclopentadiene in the C9 raw material into cyclopentadiene; Step 2: distilling the depolymerized raw material to remove light components and heavy components, and dividing the depolymerized raw material into a styrene fraction and an indene fraction according to the boiling point of the intermediate component; Step 3, mixing the styrene fraction, the indene fraction, styrene, indene and solvent oil to obtain a reaction raw material, and adding a catalyst to carry out a polymerization reaction; In the reaction raw materials, styrene and its derivatives account for 15-50 wt.% of the total amount of the reaction raw materials, indene and its derivatives account for 15-50 wt.% of the total amount of the reaction raw materials, and the content of dicyclopentadiene is less than 2 wt.%; The polymerization temperature is 0-50°C, the polymerization time is 1-4 h, and the amount of catalyst added is 0.1-1 wt.%; the catalyst is added in the following manner: firstly add a portion of the catalyst to prepare the base, then drop the reaction raw materials to carry out the polymerization reaction, and then add the remaining catalyst during the reaction; The catalyst is one or more of aluminum chloride, boron trifluoride ether complex, and boron trifluoride; the solvent oil is one or more of benzene, toluene, xylene, cyclohexane, and heptane; Step 4: After the reaction is completed, the C9 cold polymerization resin polymerization liquid is obtained by alkali washing and water washing, and then the solvent, unreacted monomers and oligomers are removed by distillation and stripping to obtain C9 cold polymerization resin with a softening point of 85-120°C and a molecular weight Mz of 2000-6000.

2. The method for preparing a low softening point, high molecular weight C9 cold polymerization resin product according to claim 1, characterized in that: The initial catalyst addition amount is 10-100 wt.% of the total catalyst addition amount, and the remaining catalyst is added evenly in multiple times during the reaction.

3. A method for preparing a low softening point, high molecular weight C9 cold polymerization resin product according to any one of claims 1-2, characterized in that: In the distillation treatment in step 2, the light components removed mainly include cyclopentadiene, methylcyclopentadiene, dicyclopentadiene, and methyldicyclopentadiene; the heavy components removed mainly include naphthalene and other polycyclic aromatic hydrocarbons; wherein the amounts of light components and heavy components removed account for 5-15 wt.% and 10-20 wt.% of the C9 raw material, respectively.

4. A method for preparing a low softening point, high molecular weight C9 cold polymerization resin product according to any one of claims 1-2, characterized in that: The main components of the styrene fraction separated in step 2 include styrene, methyl styrene, vinyl toluene, indene, and indane; among them, styrene and its derivatives account for 40-50 wt.%, indene and its derivatives account for 10-20 wt.%, and the content of dicyclopentadiene is less than 2 wt.%.

5. A method for preparing a low softening point, high molecular weight C9 cold polymerization resin product according to any one of claims 1-2, characterized in that: In the indene fraction separated in step 2, the main components include indene, indane, methyl indene, methyl styrene, and vinyl toluene; among them, indene and its derivatives account for 40-50 wt.%, styrene and its derivatives account for 10-20 wt.%, and the content of dicyclopentadiene is less than 2 wt.%.

6. A low softening point, high molecular weight C9 cold polymerization resin product, characterized in that: The C9 cold polymerization resin is obtained by the preparation method described in any one of claims 1 to 5, has a softening point of 85-120° C., a molecular weight of 2000-6000, and a Gardner color number of less than 8.