CN114276517B - Preparation method of epoxy-terminated polybutadiene series liquid rubber - Google Patents
Preparation method of epoxy-terminated polybutadiene series liquid rubber Download PDFInfo
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- CN114276517B CN114276517B CN202111520866.1A CN202111520866A CN114276517B CN 114276517 B CN114276517 B CN 114276517B CN 202111520866 A CN202111520866 A CN 202111520866A CN 114276517 B CN114276517 B CN 114276517B
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- 229920001971 elastomer Polymers 0.000 title claims abstract description 116
- 239000005060 rubber Substances 0.000 title claims abstract description 115
- 239000007788 liquid Substances 0.000 title claims abstract description 111
- 229920002857 polybutadiene Polymers 0.000 title claims abstract description 68
- 239000005062 Polybutadiene Substances 0.000 title claims abstract description 67
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- 238000006243 chemical reaction Methods 0.000 claims abstract description 56
- 229920001577 copolymer Polymers 0.000 claims abstract description 41
- 229920002121 Hydroxyl-terminated polybutadiene Polymers 0.000 claims abstract description 32
- 229920001519 homopolymer Polymers 0.000 claims abstract description 26
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 23
- 238000006735 epoxidation reaction Methods 0.000 claims abstract description 15
- 238000000034 method Methods 0.000 claims abstract description 14
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 13
- 239000003153 chemical reaction reagent Substances 0.000 claims abstract description 12
- 239000004593 Epoxy Substances 0.000 claims abstract description 10
- 125000005442 diisocyanate group Chemical group 0.000 claims abstract description 10
- 239000003960 organic solvent Substances 0.000 claims abstract description 7
- 238000002156 mixing Methods 0.000 claims abstract description 3
- 239000003054 catalyst Substances 0.000 claims description 15
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 12
- 238000005406 washing Methods 0.000 claims description 12
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 10
- RRAMGCGOFNQTLD-UHFFFAOYSA-N hexamethylene diisocyanate Chemical compound O=C=NCCCCCCN=C=O RRAMGCGOFNQTLD-UHFFFAOYSA-N 0.000 claims description 10
- 239000005057 Hexamethylene diisocyanate Substances 0.000 claims description 8
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 claims description 8
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims description 6
- DVKJHBMWWAPEIU-UHFFFAOYSA-N toluene 2,4-diisocyanate Chemical compound CC1=CC=C(N=C=O)C=C1N=C=O DVKJHBMWWAPEIU-UHFFFAOYSA-N 0.000 claims description 6
- UPMLOUAZCHDJJD-UHFFFAOYSA-N 4,4'-Diphenylmethane Diisocyanate Chemical compound C1=CC(N=C=O)=CC=C1CC1=CC=C(N=C=O)C=C1 UPMLOUAZCHDJJD-UHFFFAOYSA-N 0.000 claims description 5
- KAKZBPTYRLMSJV-UHFFFAOYSA-N Butadiene Chemical compound C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 claims description 5
- NIMLQBUJDJZYEJ-UHFFFAOYSA-N isophorone diisocyanate Chemical compound CC1(C)CC(N=C=O)CC(C)(CN=C=O)C1 NIMLQBUJDJZYEJ-UHFFFAOYSA-N 0.000 claims description 5
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims description 5
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 claims description 4
- 125000002723 alicyclic group Chemical group 0.000 claims description 4
- 125000000217 alkyl group Chemical group 0.000 claims description 4
- 125000003118 aryl group Chemical group 0.000 claims description 4
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims description 4
- 230000035484 reaction time Effects 0.000 claims description 4
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 claims description 3
- 229920000459 Nitrile rubber Polymers 0.000 claims description 3
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 claims description 3
- NTXGQCSETZTARF-UHFFFAOYSA-N buta-1,3-diene;prop-2-enenitrile Chemical compound C=CC=C.C=CC#N NTXGQCSETZTARF-UHFFFAOYSA-N 0.000 claims description 3
- 229920006395 saturated elastomer Polymers 0.000 claims description 3
- 229920003051 synthetic elastomer Polymers 0.000 claims description 3
- 239000005061 synthetic rubber Substances 0.000 claims description 3
- KXBFLNPZHXDQLV-UHFFFAOYSA-N [cyclohexyl(diisocyanato)methyl]cyclohexane Chemical compound C1CCCCC1C(N=C=O)(N=C=O)C1CCCCC1 KXBFLNPZHXDQLV-UHFFFAOYSA-N 0.000 claims description 2
- 238000001704 evaporation Methods 0.000 claims description 2
- 239000011261 inert gas Substances 0.000 claims description 2
- 150000007524 organic acids Chemical class 0.000 claims description 2
- 235000005985 organic acids Nutrition 0.000 claims description 2
- 150000007530 organic bases Chemical class 0.000 claims description 2
- 125000002524 organometallic group Chemical group 0.000 claims description 2
- 239000008096 xylene Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims 4
- IQPQWNKOIGAROB-UHFFFAOYSA-N isocyanate group Chemical group [N-]=C=O IQPQWNKOIGAROB-UHFFFAOYSA-N 0.000 abstract description 11
- 229920000642 polymer Polymers 0.000 abstract description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 4
- 239000012948 isocyanate Substances 0.000 abstract description 2
- 238000003756 stirring Methods 0.000 description 29
- 239000012300 argon atmosphere Substances 0.000 description 20
- 238000004321 preservation Methods 0.000 description 19
- 238000001816 cooling Methods 0.000 description 17
- 238000010438 heat treatment Methods 0.000 description 14
- 125000003700 epoxy group Chemical group 0.000 description 13
- UHOVQNZJYSORNB-UHFFFAOYSA-N benzene Substances C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 10
- 239000005457 ice water Substances 0.000 description 10
- 238000010025 steaming Methods 0.000 description 10
- 238000010521 absorption reaction Methods 0.000 description 6
- 239000002131 composite material Substances 0.000 description 6
- 229920003048 styrene butadiene rubber Polymers 0.000 description 6
- RIOQSEWOXXDEQQ-UHFFFAOYSA-N triphenylphosphine Chemical compound C1=CC=CC=C1P(C=1C=CC=CC=1)C1=CC=CC=C1 RIOQSEWOXXDEQQ-UHFFFAOYSA-N 0.000 description 6
- UKLDJPRMSDWDSL-UHFFFAOYSA-L [dibutyl(dodecanoyloxy)stannyl] dodecanoate Chemical compound CCCCCCCCCCCC(=O)O[Sn](CCCC)(CCCC)OC(=O)CCCCCCCCCCC UKLDJPRMSDWDSL-UHFFFAOYSA-L 0.000 description 5
- 239000012975 dibutyltin dilaurate Substances 0.000 description 5
- 239000000853 adhesive Substances 0.000 description 4
- 230000001070 adhesive effect Effects 0.000 description 4
- -1 methyl epoxypropanol Chemical compound 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 239000003607 modifier Substances 0.000 description 4
- 150000002825 nitriles Chemical class 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 239000004014 plasticizer Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 229920001187 thermosetting polymer Polymers 0.000 description 4
- GJOWSEBTWQNKPC-UHFFFAOYSA-N 3-methyloxiran-2-ol Chemical compound CC1OC1O GJOWSEBTWQNKPC-UHFFFAOYSA-N 0.000 description 3
- 239000005058 Isophorone diisocyanate Substances 0.000 description 3
- 238000007385 chemical modification Methods 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000004449 solid propellant Substances 0.000 description 3
- 239000002174 Styrene-butadiene Substances 0.000 description 2
- ISKQADXMHQSTHK-UHFFFAOYSA-N [4-(aminomethyl)phenyl]methanamine Chemical compound NCC1=CC=C(CN)C=C1 ISKQADXMHQSTHK-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- MTAZNLWOLGHBHU-UHFFFAOYSA-N butadiene-styrene rubber Chemical compound C=CC=C.C=CC1=CC=CC=C1 MTAZNLWOLGHBHU-UHFFFAOYSA-N 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000005984 hydrogenation reaction Methods 0.000 description 2
- 238000002329 infrared spectrum Methods 0.000 description 2
- 239000006193 liquid solution Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229920002239 polyacrylonitrile Polymers 0.000 description 2
- 239000011115 styrene butadiene Substances 0.000 description 2
- CTKINSOISVBQLD-UHFFFAOYSA-N Glycidol Chemical compound OCC1CO1 CTKINSOISVBQLD-UHFFFAOYSA-N 0.000 description 1
- 229920003006 Polybutadiene acrylonitrile Polymers 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000806 elastomer Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000001879 gelation Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 150000002513 isocyanates Chemical group 0.000 description 1
- 229920002587 poly(1,3-butadiene) polymer Polymers 0.000 description 1
- 229920001748 polybutylene Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229920006250 telechelic polymer Polymers 0.000 description 1
- ZHXAZZQXWJJBHA-UHFFFAOYSA-N triphenylbismuthane Chemical compound C1=CC=CC=C1[Bi](C=1C=CC=CC=1)C1=CC=CC=C1 ZHXAZZQXWJJBHA-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/80—Technologies aiming to reduce greenhouse gasses emissions common to all road transportation technologies
- Y02T10/86—Optimisation of rolling resistance, e.g. weight reduction
Landscapes
- Polyurethanes Or Polyureas (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Epoxy Resins (AREA)
Abstract
The application discloses a preparation method of epoxy terminated polybutadiene series liquid rubber, which comprises the following steps: step one: under inert environment, mixing an organic solvent and hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber according to the mass ratio of (0-5) to 1, adding diisocyanate according to the mol ratio of isocyanate groups to hydroxyl groups of 2-5, and reacting to prepare isocyanate-terminated polybutadiene homopolymer or copolymer liquid rubber solution; step two: and adding the epoxidation reagent into the obtained liquid rubber solution of the homopolymer or copolymer of the terminal isocyanate polybutadiene for reaction in an inert environment according to the molar ratio of hydroxyl groups to isocyanate groups in the epoxidation reagent of 1-3. The reaction liquid is washed by water and steamed by spin to obtain the epoxy-terminated polybutadiene series liquid rubber. The preparation method is simple in process, the end epoxidation efficiency is adjustable, and the obtained epoxy-terminated polybutadiene liquid rubber has the characteristics of excellent water resistance, fluidity, adhesion, toughness, good compatibility with other polymers and the like.
Description
Technical Field
The application relates to the field of preparation of end-group functionalized polymers, in particular to a preparation method of epoxy terminated polybutadiene series liquid rubber.
Background
The polybutadiene series liquid rubber containing reactive hydroxyl groups is a polymer with the number average molecular weight less than 10000 and fluidity at room temperature, and is also called telechelic polymer because the molecular chain end carries reactive hydroxyl groups. The liquid rubber can be crosslinked and solidified through chemical reaction to form an elastomer with a three-dimensional network structure and certain mechanical properties. The current liquid rubber varieties of hydroxyl-terminated polybutadiene series synthesized at home and abroad mainly comprise hydroxyl-terminated polybutadiene (HTPB), hydroxyl-terminated polybutadiene-acrylonitrile (HTBN), hydroxyl-terminated polybutadiene-styrene (HTBS) and the like. The hydroxyl-terminated polybutadiene series liquid rubber has the advantages of low viscosity, easiness in compounding with other polymers and fillers, excellent mechanical properties after curing and forming and the like, is widely applied to the fields of composite solid propellant, polyurethane matched materials and the like, and is widely applied to the industries of aerospace, electronic appliances, ships, automobiles, chemical industry and the like. In order to meet the increasingly high engineering application requirements, the chemical modification of the traditional hydroxyl-terminated polybutadiene liquid rubber series to improve the comprehensive performance thereof becomes a convenient and important method.
Epoxy groups are introduced into the hydroxy-terminated polybutadiene series liquid rubber through epoxidation modification, so that the intermolecular acting force of the liquid rubber can be increased, the liquid rubber has good adhesion and is well compatible with materials with wider polarity ranges, and a new thought is provided for preparing the composite material with excellent performance. However, the method is limited by the problems of unstable preparation process, undefined chemical structure of synthesized products and the like, so that the liquid rubber of the epoxidized modified polybutadiene series is not applied on a large scale. The molecular chain of polybutadiene is rich in unsaturated double bond and active hydroxyl end, and the epoxidation modification of the current para-hydroxyl polybutadiene liquid rubber mainly adopts a double bond oxidation method and a terminal group conversion method in the molecular chain. The double bond oxidation method has poor controllability and low yield, the product is easy to branch and gel, and the molecular structure and composition are difficult to clearly characterize. Therefore, the preparation of the epoxy-terminated polybutadiene series liquid rubber with definite chemical structure, strong designability, stable and controllable reaction and excellent comprehensive performance is still a challenge to be solved.
Disclosure of Invention
In view of the above, the present invention provides a method for preparing an epoxy-terminated polybutadiene liquid rubber, which solves the above-mentioned disadvantages.
In order to achieve the above object, an embodiment of the present invention provides a method for preparing an epoxy-terminated polybutadiene series liquid rubber, comprising:
step one: under an inert environment, mixing an organic solvent and hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber according to a mass ratio (0-5) of 1, adding diisocyanate according to an r value of 2-5, and reacting to obtain an isocyanate-terminated polybutadiene homopolymer or copolymer liquid rubber solution, wherein the r value is the molar ratio of-NCO groups in the diisocyanate to-OH groups in the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber;
step two: and in an inert environment, adding an epoxidation reagent into the liquid rubber solution of the isocyanate-terminated polybutadiene homopolymer or copolymer for reaction according to the r 'value of 1-3, and washing and spin-evaporating the reaction liquid to obtain the epoxy-terminated polybutadiene series liquid rubber, wherein the r' value is the molar ratio of the-OH group in the epoxidation reagent to the-NCO group in the liquid rubber solution of the isocyanate-terminated polybutadiene homopolymer or copolymer.
The preparation method has the advantages of simple process, mild reaction conditions and the like.
Preferably, in the first step, the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber is selected from butadiene homopolymer or copolymer liquid rubber containing hydroxyl groups at both ends, the number average molecular weight is 200-10000, the hydroxyl value is 0.1-5.0 mmol/g, and the general formula is: HO-R 1 -OH; wherein R is 1 Is a hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber main chain, and is selected from any one of polybutadiene, butadiene acrylonitrile copolymer, butadiene styrene copolymer, butadiene acrylic acrylonitrile copolymer, butadiene acrylic ester copolymer, butadiene-isoprene copolymer and the product of the saturated hydrogenation of the synthetic rubber.
Preferably, in the first step, the organic solvent is any one of tetrahydrofuran, dimethyl sulfoxide, toluene, xylene, chlorobenzene, dichloromethane, and 1, 4-dioxane.
Preferably, in the first step, the diisocyanate has a general formula: OCN-R 2 -NCO; wherein R is 2 Is alkyl, aryl, alicyclic or benzyl, selected from isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylMethane Diisocyanate (HMDI), toluene Diisocyanate (TDI), hexamethylene Diisocyanate (HDI).
Preferably, in the second step, the structural general formula of the epoxidation reagent is as follows:
wherein R is 3 Is alkyl, aryl, alicyclic or benzyl, n=0 or 1.
Preferably, in the first step, in the reaction by adding diisocyanate, a catalyst may be further added, and the feeding ratio of the catalyst to the total mass of the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber solution is (0-0.5): 100.
preferably, in the second step, in the reaction of adding the epoxidation reagent into the liquid rubber solution of the isocyanate-terminated polybutadiene homopolymer or copolymer according to the r' value of 1-3, a catalyst can be further added, and the feeding ratio of the catalyst to the total mass of the liquid rubber solution of the isocyanate-terminated polybutadiene homopolymer or copolymer is (0-0.5): 100.
preferably, the catalyst is selected from any one of organometallic catalysts, organic bases and organic acids catalysts.
Preferably, the reaction vessel is replaced with inert gas/vacuum multiple times, allowing the reaction mass to be added under inert conditions.
Preferably, the reaction temperature in the reaction kettle is 45-90 ℃, the reaction time of the first step is 1-8 hours, and the reaction time of the second step is 2-12 hours.
The inventor carries out mechanism analysis on the preparation process based on epoxy-terminated polybutadiene series liquid rubber and product characterization data, and the mechanism analysis can be as follows: in the first step, the high-activity hydroxyl in the added hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber is easy to react with isocyanate groups, so that the hydroxyl at the two ends of the hydroxyl-terminated butadiene copolymer liquid rubber molecule is converted into isocyanate groups, thereby facilitating the subsequent introduction of epoxy groups; in the second step, the added epoxidizing agent reacts with isocyanate groups to introduce epoxy groups, so that the purpose of converting hydroxyl groups at two ends of a molecular chain of the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber into epoxy groups is achieved, and finally the epoxy-terminated polybutadiene series liquid rubber is obtained. By the end group conversion technology, the end hydroxyl groups at the two ends of the molecular chain of the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber are converted into epoxy groups, and the specific chemical reaction general formula is as follows:
in the chemical reaction formula, R 1 The main chain of the liquid rubber is any one of polybutadiene, butadiene-acrylonitrile copolymer, butadiene-styrene copolymer, butadiene-acrylic acid-acrylonitrile copolymer, butadiene-acrylic acid ester copolymer, butadiene-isoprene copolymer and the product of the saturated hydrogenation of the synthetic rubber.
The technical scheme provided by the embodiment of the application can comprise the following beneficial effects:
according to the preparation method provided by the embodiment of the application, the hydroxyl-terminated polybutadiene series liquid rubber can be modified, and epoxy groups are introduced to the two ends of a molecular chain of the hydroxyl-terminated polybutadiene series liquid rubber, so that the epoxy-terminated polybutadiene series liquid rubber with lower viscosity is prepared.
The product of the invention carries out definite chemical modification on the end group of the liquid rubber, the product has good fluidity under the condition of room temperature or slightly heating, the processing technology is stable, and the prepared final composite material has excellent mechanical properties. The product is mainly used in the fields of adhesives, solid rubber reactive plasticizers, toughening modifiers of thermosetting resins and the like, and particularly can be widely used in scenes such as composite solid propellants, gas generating agents, secondary roll control system adhesives, solid rubber reactive plasticizers, toughening modifiers of thermosetting resins such as epoxy and the like.
The preparation method of the epoxy-terminated polybutadiene series liquid rubber provided by the embodiment of the invention has the advantages of simple process, adjustable end ring oxidation efficiency and better commercial application value. The prepared epoxy-terminated polybutadiene series liquid rubber has the characteristics of excellent water resistance, good fluidity, good adhesion, good toughness, good compatibility with other polymers and the like.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application.
FIG. 1 is an infrared spectrum of an isocyanate-terminated polybutadiene, according to an exemplary embodiment, as can be seen from FIG. 1, 3500cm -1 the-OH absorption peak at the site disappeared, while at 3300cm -1 -NH-characteristic absorption peaks appear there; at 1730cm -1 At which a=c=o absorption peak is formed; 2270cm -1 The vicinity of the absorption peak of-NCO indicates that the-OH in the hydroxyl-terminated polybutadiene and the-NCO in the diisocyanate have complete chemical reaction to generate the isocyanate-terminated polybutadiene with urethane bonds on the main chain and isocyanate groups at both ends.
Fig. 2 is an infrared spectrum of an epoxy-terminated polybutadiene shown according to an exemplary embodiment. As can be seen from FIG. 2, 2270cm -1 the-NCO absorption peak at this point disappeared and the epoxy-terminated polybutadiene was at 846cm -1 Characteristic absorption peaks of epoxy groups appear at the left and right sides, which indicates that the end group of the isocyanate-terminated polybutadiene is completely reacted with an epoxidation reagent to generate the epoxy-terminated polybutadiene.
Detailed Description
Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present application as detailed in the accompanying claims.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be appreciated that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items
Example 1:
step one: adding 60.0g of hydroxyl-terminated polybutadiene liquid rubber and 180.0g of dimethylbenzene into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 90 ℃, adding 26.79g of hexamethylene diisocyanate under the stirring state, and carrying out heat preservation reaction for 4 hours to obtain an isocyanate-terminated polybutadiene liquid rubber solution;
step two: and cooling the prepared isocyanate-terminated polybutadiene liquid rubber solution to 80 ℃ under argon atmosphere, adding 19.04g of 4- (ethylene oxide-2-methoxy) -1-butanol and 0.1429g of triphenylphosphine under stirring, reacting for 6 hours under heat preservation, cooling the reaction liquid to room temperature after the reaction is finished, and washing and steaming the reaction liquid by ice water to obtain the epoxy-terminated polybutadiene liquid rubber.
Example 2:
step one: adding 60.0g of hydroxyl-terminated polybutadiene liquid rubber and 120.0g of tetrahydrofuran into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 60 ℃, adding 8.45g of hexamethylene diisocyanate under the stirring state, and carrying out heat preservation reaction for 3 hours to obtain an isocyanate-terminated polybutadiene liquid rubber solution;
step two: and heating the prepared liquid rubber solution of the isocyanate-terminated polybutadiene to 90 ℃ under the argon atmosphere, adding 7.26g of methyl epoxypropanol and 0.9786g of dibutyltin diacetate under the stirring state, carrying out heat preservation reaction for 4 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and rotary steaming the reaction liquid by ice water to obtain the liquid rubber of the epoxy-terminated polybutadiene.
Example 3:
step one: adding 60.0g of hydroxyl-terminated polybutyl-benzene liquid rubber and 60.0g of toluene into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 80 ℃, adding 66.16g of isophorone diisocyanate and 0.1862g of dibutyltin dilaurate under the stirring state, and carrying out heat preservation reaction for 2 hours to obtain an isocyanate-terminated polybutyl-benzene liquid rubber solution;
step two: and cooling the prepared solution of the end isocyanate-group polymerized styrene-butadiene liquid rubber to 50 ℃ under argon atmosphere, adding 23.15g of epoxy propanol under stirring, carrying out heat preservation reaction for 5 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and steaming the reaction liquid by ice water to obtain the end epoxy-group polymerized styrene-butadiene liquid rubber.
Example 4:
step one: adding 60.0g of hydroxyl-terminated polybutylece nitrile liquid rubber and 300.0g of dimethylbenzene into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 45 ℃, adding 37.36g of toluene diisocyanate and 0.5960g of triphenylbismuth under the stirring state, and carrying out heat preservation reaction for 4 hours to prepare an isocyanate-terminated polybutylece nitrile liquid rubber solution;
step two: and heating the prepared isocyanate-terminated poly (nitrile) liquid rubber to 80 ℃ under the argon atmosphere, adding 39.70g of 4- (ethylene oxide-2-methoxy) -1-butanol under the stirring state, carrying out heat preservation reaction for 6 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and rotary steaming the reaction liquid by ice water to obtain the epoxy-terminated poly (nitrile) liquid rubber.
Example 5:
step one: adding 60.0g of hydroxyl-terminated polybutadienes benzene liquid rubber into a 500ml three-neck flask under argon atmosphere, reacting at 90 ℃, adding 4.01g of isophorone diisocyanate under stirring, and reacting for 8 hours under heat preservation to obtain an isocyanate-terminated polybutadienes benzene liquid rubber solution, wherein the organic solvent can be omitted, and the organic solvent is not added in the embodiment;
step two: and cooling the prepared liquid solution of the end isocyanate-group polymerized styrene-butadiene rubber to 45 ℃ under argon atmosphere, adding 0.55g of glycidol and 0.1614g of dibutyltin dilaurate into the solution under stirring, carrying out heat preservation reaction for 12 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and rotary steaming the reaction liquid by ice water to obtain the end epoxy-group polymerized styrene-butadiene rubber.
Example 6:
step one: adding 60.0g of hydroxyl-terminated polyacrylonitrile-butadiene-acrylate liquid rubber and 150.0g of 1, 4-dioxane into a 500ml three-neck flask under the argon atmosphere, stirring, dissolving and heating to 65 ℃, adding 41.07g of toluene diisocyanate and 0.6277g of dibutyltin dilaurate under the stirring state, and carrying out thermal insulation reaction for 4 hours to obtain isocyanate-terminated polyacrylonitrile-butadiene-acrylate liquid rubber solution;
step two: and (3) cooling the prepared isocyanate-terminated poly (polyacrylonitrile) -butadiene-acrylate liquid rubber solution to 60 ℃ under argon atmosphere, adding 31.16g of methyl epoxy propanol under stirring, carrying out heat preservation reaction for 8 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and steaming the reaction liquid by ice water to obtain the epoxy-terminated poly (polyacrylonitrile) -butadiene-acrylate liquid rubber.
Example 7:
step one: adding 60.0g of hydroxyl-terminated polybutadiene-isoprene liquid rubber and 90.0g of tetrahydrofuran into a 500ml three-neck flask under the argon atmosphere, stirring, dissolving, heating to 70 ℃, adding 41.31g of diphenylmethane diisocyanate and 0.9566g of triphenylphosphine under the stirring state, and carrying out heat preservation reaction for 5 hours to prepare an isocyanate-terminated polybutadiene-isoprene liquid rubber solution;
step two: and heating the prepared hydroxyl-terminated polybutadiene-isoprene liquid rubber with the isocyanate groups to 80 ℃ in an argon atmosphere, adding 16.29g of epoxy propanol under stirring, carrying out heat preservation reaction for 4 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and steaming the reaction liquid by ice water to obtain the epoxy-terminated polybutadiene-isoprene liquid rubber.
Example 8:
step one: adding 60.0g of hydroxyl-terminated polybutadiene liquid rubber and 120.0g of tetrahydrofuran into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 60 ℃, adding 8.45g of hexamethylene diisocyanate under the stirring state, and carrying out heat preservation reaction for 3 hours to obtain an isocyanate-terminated polybutadiene liquid rubber solution;
step two: and cooling the prepared liquid rubber solution of the isocyanate-terminated polybutadiene to 30 ℃ under the argon atmosphere, adding 7.26g of methyl epoxy propanol and 0.9786g of dibutyltin diacetate under the stirring state, carrying out heat preservation reaction for 12 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and rotary steaming the reaction liquid by ice water to obtain the liquid rubber of the epoxy-terminated polybutadiene.
Example 9:
step one: adding 60.0g of hydroxyl-terminated polybutadiene liquid rubber and 180.0g of dimethylbenzene into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 90 ℃, adding 10.14g of hexamethylene diisocyanate under the stirring state, and carrying out heat preservation reaction for 4 hours to obtain an isocyanate-terminated polybutadiene liquid rubber solution;
step two: and cooling the prepared isocyanate-terminated polybutadiene liquid rubber solution to 80 ℃ under argon atmosphere, adding 30.87g of 4- (ethylene oxide-2-methoxy) -1-butanol and 0.1405g of triphenylphosphine under stirring, reacting for 6 hours under heat preservation, cooling the reaction liquid to room temperature after the reaction is finished, and washing and steaming the reaction liquid by ice water to obtain the epoxy-terminated polybutadiene liquid rubber.
Example 10:
step one: adding 60.0g of hydroxyl-terminated polybutyl-benzene liquid rubber and 60.0g of toluene into a 500ml three-neck flask under the argon atmosphere, stirring and dissolving, heating to 80 ℃, adding 66.16g of isophorone diisocyanate and 0.1862g of dibutyltin dilaurate under the stirring state, and carrying out heat preservation reaction for 2 hours to obtain an isocyanate-terminated polybutyl-benzene liquid rubber solution;
step two: and cooling the prepared liquid solution of the end isocyanate-group polymerized styrene-butadiene rubber to 50 ℃ under the argon atmosphere, adding 23.15g of epoxy propanol and 1.2565g of dibutyltin dilaurate into the solution under the stirring state, carrying out heat preservation reaction for 2 hours, cooling the reaction liquid to room temperature after the reaction is finished, and washing and rotary steaming the reaction liquid by ice water to obtain the end epoxy-group polymerized styrene-butadiene rubber.
Table 1: example 1-example 10 formulation and process
Table 2: example 1-example 10 physical and chemical Properties of epoxy-terminated polybutadiene liquid rubber series
Examples | Viscosity (40 ℃ C.)/Pa s | Epoxy value/mmol/g | Number average molecular weight |
1 | 7.35 | 1.694 | 4300 |
2 | 30.95 | 0.578 | 8200 |
3 | 3.78 | 4.983 | 428 |
4 | 14.89 | 2.607 | 5800 |
5 | 39.23 | 0.113 | 9800 |
6 | 4.52 | 3.854 | 1300 |
7 | 10.75 | 1.224 | 4800 |
8 | 18.34 | 0.228 | 6000 |
9 | Too great viscosity to measure | 1.624 | 11000 |
10 | Too great viscosity to measure | 4.502 | 2600 |
FIGS. 1 and 2 show the isocyanate-terminated polybutylenes prepared in example 1Infrared contrast plot of alkene and end epoxy polybutadiene. As can be seen from FIG. 2, the wave number is 2270cm -1 At this point, the-NCO characteristic peaks before and after the epoxy modification disappeared, and therefore it was judged that the NCO group at the molecular chain end of the terminal isocyanate group-terminated polybutadiene molecular chain end prepolymer was completely converted into an epoxy group.
According to the above examples 1, 2, 3, 4, 5, 6 and 7, the preparation method provided by the invention can be used for modifying the hydroxyl-terminated polybutadiene series liquid rubber, introducing epoxy groups into two ends of a molecular chain of the hydroxyl-terminated polybutadiene series liquid rubber to prepare the epoxy-terminated polybutadiene series liquid rubber with lower viscosity, wherein the number average molecular weight of the epoxy-terminated polybutadiene series liquid rubber is 400-10000, the epoxy value is 0.1-5.0 mmol/g, and the viscosity (40 ℃) is 3-40 Pa.s.
As is clear from comparative examples 1 and 9, when the amount of the added epoxidation reagent is too large, the difficulty of post-treatment is increased, and the residual excessive epoxidation reagent in the system undergoes side reactions, and the product is solidified, thereby losing fluidity; as can be seen from comparative examples 2 and 8, if the reaction temperature in the second step is too low, the conversion efficiency of the epoxy group is affected, resulting in a lower epoxy value content; as is clear from comparative examples 3 and 10, although the addition of the catalyst can accelerate the reaction rate, too much addition results in crosslinking of the reaction system and gelation, and the product after post-treatment is not measured due to too high viscosity, which greatly affects the application performance of the product.
The hydroxyl-terminated polybutadiene series liquid rubber has definite chemical modification of the hydroxyl-terminated groups of the hydroxyl-terminated polybutadiene series liquid rubber, the prepared epoxy-terminated polybutadiene series liquid rubber product has good fluidity at room temperature or under slightly heating, the processing technology is stable, and the prepared final composite material has excellent mechanical properties. The product is mainly used in the fields of adhesives, solid rubber reactive plasticizers, toughening modifiers of thermosetting resins and the like, and particularly can be widely used in scenes such as composite solid propellants, gas generating agents, secondary roll control system adhesives, solid rubber reactive plasticizers, toughening modifiers of thermosetting resins such as epoxy and the like.
The preparation method of the epoxy-terminated polybutadiene series liquid rubber provided by the embodiment of the invention has the advantages of simple process, adjustable end ring oxidation efficiency and better commercial application value. The prepared epoxy-terminated polybutadiene series liquid rubber has the characteristics of excellent water resistance, good fluidity, good adhesion, good toughness, good compatibility with other polymers and the like.
Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure. This application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.
It is to be understood that the present application is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the application is limited only by the appended claims.
Claims (6)
1. A preparation method of epoxy-terminated polybutadiene series liquid rubber is characterized by comprising the following steps:
step one: under an inert environment, mixing an organic solvent and hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber according to a mass ratio (0-5) of 1, adding diisocyanate according to an r value of 2-5, and reacting to obtain an isocyanate-terminated polybutadiene homopolymer or copolymer liquid rubber solution, wherein the r value is the molar ratio of-NCO groups in the diisocyanate to-OH groups in the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber;
step two: adding an epoxidation reagent into an isocyanate-terminated polybutadiene homopolymer or copolymer liquid rubber solution for reaction in an inert environment according to the r 'value of 1-3, and washing and spin-evaporating the reaction liquid to obtain an epoxy-terminated polybutadiene series liquid rubber, wherein the r' value is the molar ratio of an-OH group in the epoxidation reagent to an-NCO group in the isocyanate-terminated polybutadiene homopolymer or copolymer liquid rubber;
in the first step, in the reaction by adding diisocyanate, adding a catalyst, wherein the feeding ratio of the catalyst to the total mass of the hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber solution is (0-0.5): 100;
step two, adding a catalyst into the liquid rubber solution of the isocyanate-terminated polybutadiene homopolymer or copolymer for reaction according to the r' value of 1-3, wherein the feeding ratio of the catalyst to the total mass of the liquid rubber solution of the isocyanate-terminated polybutadiene homopolymer or copolymer is (0-0.05): 100;
in the second step, the structural general formula of the epoxidation reagent is shown as follows:
wherein R is 3 Is alkyl, aryl, alicyclic or benzyl, n=0 or 1;
the reaction temperature in the reaction kettle is 65-90 ℃ and the reaction time is 1-5h; and step two, the reaction temperature in the reaction kettle is 50-80 ℃ and the reaction time is 4-8h.
2. The method for preparing a series of liquid rubbers of epoxy terminated polybutadiene according to claim 1, wherein in the first step, the liquid rubbers of hydroxyl terminated polybutadiene homopolymer or copolymer are selected from the group consisting of liquid rubbers of butadiene homo-or copolymer having hydroxyl groups at both ends, the number average molecular weight is 200-10000, the hydroxyl value is 0.1-5.0 mmol/g, and the general formula is: HO-R 1 -OH; wherein R is 1 Is a hydroxyl-terminated polybutadiene homopolymer or copolymer liquid rubber main chain selected from polybutadiene, butadiene-acrylonitrile copolymer, butadiene-styrene copolymer, butadiene-acrylic acrylonitrile copolymer, and butyleneAn enacrylate copolymer, a butadiene-isoprene copolymer, and any one of the above synthetic rubber saturated hydrogenated products.
3. The method for producing an epoxy-terminated polybutadiene series liquid rubber according to claim 1, wherein in the first step, the organic solvent is any one of tetrahydrofuran, dimethyl sulfoxide, toluene, xylene, chlorobenzene, methylene chloride, and 1, 4-dioxane.
4. The method for producing a liquid rubber of the epoxy-terminated polybutadiene series according to claim 1, wherein in the first step, the diisocyanate has the general formula: OCN-R 2 -NCO, where R 2 Is an alkyl group, an aryl group or an alicyclic group, and is selected from any one of isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), toluene Diisocyanate (TDI) and Hexamethylene Diisocyanate (HDI).
5. The method for producing an epoxy-terminated polybutadiene series liquid rubber according to claim 1, wherein said catalyst is selected from any one of organometallic catalysts, organic bases and organic acids catalysts.
6. The process for preparing an epoxy-terminated polybutadiene series liquid rubber according to claim 1, wherein the reaction vessel is replaced with an inert gas/vacuum a plurality of times to allow the reaction mass to be added under an inert atmosphere.
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