CN114057927A - Method for preparing vinyl chloride-vinyl acetate copolymer - Google Patents
Method for preparing vinyl chloride-vinyl acetate copolymer Download PDFInfo
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- CN114057927A CN114057927A CN202111390470.XA CN202111390470A CN114057927A CN 114057927 A CN114057927 A CN 114057927A CN 202111390470 A CN202111390470 A CN 202111390470A CN 114057927 A CN114057927 A CN 114057927A
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- vinyl acetate
- vinyl chloride
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- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000006243 chemical reaction Methods 0.000 claims abstract description 61
- 239000003999 initiator Substances 0.000 claims abstract description 45
- 238000003756 stirring Methods 0.000 claims abstract description 19
- 229920001577 copolymer Polymers 0.000 claims abstract description 13
- 239000002270 dispersing agent Substances 0.000 claims description 33
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 claims description 23
- 239000002002 slurry Substances 0.000 claims description 22
- 239000008367 deionised water Substances 0.000 claims description 20
- 229910021641 deionized water Inorganic materials 0.000 claims description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 20
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 claims description 18
- 238000001035 drying Methods 0.000 claims description 18
- 239000011259 mixed solution Substances 0.000 claims description 15
- 239000000843 powder Substances 0.000 claims description 10
- 239000002131 composite material Substances 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 7
- 239000004372 Polyvinyl alcohol Substances 0.000 claims description 6
- 230000018044 dehydration Effects 0.000 claims description 6
- 238000006297 dehydration reaction Methods 0.000 claims description 6
- 238000007599 discharging Methods 0.000 claims description 6
- 239000001866 hydroxypropyl methyl cellulose Substances 0.000 claims description 6
- 229920003088 hydroxypropyl methyl cellulose Polymers 0.000 claims description 6
- 235000010979 hydroxypropyl methyl cellulose Nutrition 0.000 claims description 6
- UFVKGYZPFZQRLF-UHFFFAOYSA-N hydroxypropyl methyl cellulose Chemical compound OC1C(O)C(OC)OC(CO)C1OC1C(O)C(O)C(OC2C(C(O)C(OC3C(C(O)C(O)C(CO)O3)O)C(CO)O2)O)C(CO)O1 UFVKGYZPFZQRLF-UHFFFAOYSA-N 0.000 claims description 6
- 239000000178 monomer Substances 0.000 claims description 6
- 229920002451 polyvinyl alcohol Polymers 0.000 claims description 6
- 238000007873 sieving Methods 0.000 claims description 5
- ZACVGCNKGYYQHA-UHFFFAOYSA-N 2-ethylhexoxycarbonyloxy 2-ethylhexyl carbonate Chemical compound CCCCC(CC)COC(=O)OOC(=O)OCC(CC)CCCC ZACVGCNKGYYQHA-UHFFFAOYSA-N 0.000 claims description 4
- UPAJQFJIBSDYDZ-UHFFFAOYSA-N 3,5-dimethylheptanoyl 3,5-dimethylheptaneperoxoate Chemical compound CCC(C)CC(C)CC(=O)OOC(=O)CC(C)CC(C)CC UPAJQFJIBSDYDZ-UHFFFAOYSA-N 0.000 claims description 4
- DNJIEGIFACGWOD-UHFFFAOYSA-N ethyl mercaptane Natural products CCS DNJIEGIFACGWOD-UHFFFAOYSA-N 0.000 claims description 3
- 239000007788 liquid Substances 0.000 claims description 3
- DGVVWUTYPXICAM-UHFFFAOYSA-N β‐Mercaptoethanol Chemical group OCCS DGVVWUTYPXICAM-UHFFFAOYSA-N 0.000 claims description 3
- OPQYOFWUFGEMRZ-UHFFFAOYSA-N tert-butyl 2,2-dimethylpropaneperoxoate Chemical compound CC(C)(C)OOC(=O)C(C)(C)C OPQYOFWUFGEMRZ-UHFFFAOYSA-N 0.000 claims 1
- 229920005989 resin Polymers 0.000 abstract description 20
- 239000011347 resin Substances 0.000 abstract description 20
- 239000000126 substance Substances 0.000 abstract description 9
- HGAZMNJKRQFZKS-UHFFFAOYSA-N chloroethene;ethenyl acetate Chemical compound ClC=C.CC(=O)OC=C HGAZMNJKRQFZKS-UHFFFAOYSA-N 0.000 abstract description 5
- 150000002148 esters Chemical class 0.000 abstract description 3
- 239000003960 organic solvent Substances 0.000 abstract description 3
- 239000000376 reactant Substances 0.000 abstract description 3
- 238000007796 conventional method Methods 0.000 abstract description 2
- 238000000354 decomposition reaction Methods 0.000 abstract description 2
- 230000002349 favourable effect Effects 0.000 abstract description 2
- 239000000463 material Substances 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 6
- 229920006026 co-polymeric resin Polymers 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 239000000047 product Substances 0.000 description 4
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 description 4
- 239000012086 standard solution Substances 0.000 description 4
- HGXJDMCMYLEZMJ-UHFFFAOYSA-N (2-methylpropan-2-yl)oxy 2,2-dimethylpropaneperoxoate Chemical compound CC(C)(C)OOOC(=O)C(C)(C)C HGXJDMCMYLEZMJ-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 238000004448 titration Methods 0.000 description 3
- 238000005303 weighing Methods 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- FOCAUTSVDIKZOP-UHFFFAOYSA-N chloroacetic acid Chemical compound OC(=O)CCl FOCAUTSVDIKZOP-UHFFFAOYSA-N 0.000 description 2
- 238000007334 copolymerization reaction Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000977 initiatory effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229910001961 silver nitrate Inorganic materials 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 238000010557 suspension polymerization reaction Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000000052 vinegar Substances 0.000 description 2
- 102100037709 Desmocollin-3 Human genes 0.000 description 1
- 101000968042 Homo sapiens Desmocollin-2 Proteins 0.000 description 1
- 101000880960 Homo sapiens Desmocollin-3 Proteins 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000006172 buffering agent Substances 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007720 emulsion polymerization reaction Methods 0.000 description 1
- PVBRSNZAOAJRKO-UHFFFAOYSA-N ethyl 2-sulfanylacetate Chemical group CCOC(=O)CS PVBRSNZAOAJRKO-UHFFFAOYSA-N 0.000 description 1
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010528 free radical solution polymerization reaction Methods 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 239000000976 ink Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- CASUWPDYGGAUQV-UHFFFAOYSA-M potassium;methanol;hydroxide Chemical compound [OH-].[K+].OC CASUWPDYGGAUQV-UHFFFAOYSA-M 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 150000003254 radicals Chemical class 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- PRZSXZWFJHEZBJ-UHFFFAOYSA-N thymol blue Chemical compound C1=C(O)C(C(C)C)=CC(C2(C3=CC=CC=C3S(=O)(=O)O2)C=2C(=CC(O)=C(C(C)C)C=2)C)=C1C PRZSXZWFJHEZBJ-UHFFFAOYSA-N 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F214/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
- C08F214/02—Monomers containing chlorine
- C08F214/04—Monomers containing two carbon atoms
- C08F214/06—Vinyl chloride
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2/00—Processes of polymerisation
- C08F2/12—Polymerisation in non-solvents
- C08F2/16—Aqueous medium
- C08F2/18—Suspension polymerisation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2/00—Processes of polymerisation
- C08F2/12—Polymerisation in non-solvents
- C08F2/16—Aqueous medium
- C08F2/20—Aqueous medium with the aid of macromolecular dispersing agents
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F218/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an acyloxy radical of a saturated carboxylic acid, of carbonic acid or of a haloformic acid
- C08F218/02—Esters of monocarboxylic acids
- C08F218/04—Vinyl esters
- C08F218/08—Vinyl acetate
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Polymerisation Methods In General (AREA)
Abstract
The invention relates to the technical field of vinyl chloride-vinyl acetate resin, in particular to a method for preparing vinyl chloride-vinyl acetate copolymer. The vinyl chloride-vinyl acetate copolymer resin obtained by the conventional method inevitably contains more copolymer insoluble substances with ultrahigh molecular weight, and the solubility of the vinyl chloride-vinyl acetate copolymer in an ester organic solvent is influenced to a certain extent. Based on the problems, the invention provides a method for preparing vinyl chloride-vinyl acetate copolymer, and the method adds the initiator after the material temperature in the reaction kettle reaches the reaction set temperature, so that the initiator does not have decomposition phenomenon in the processes of cold stirring and temperature rise of reactants, the condition that the initiator is decomposed at low temperature in the temperature rise process to initiate reaction to generate ultra-high molecular weight copolymer insoluble substances is avoided, and the method is very favorable for improving the solubility of the vinyl chloride-vinyl acetate copolymer.
Description
Technical Field
The invention relates to the technical field of vinyl chloride-vinyl acetate resin, in particular to a method for preparing vinyl chloride-vinyl acetate copolymer.
Background
Vinyl chloride-vinyl acetate (VCM-VAc) copolymer, commonly known as a vinyl chloride-vinyl acetate copolymer resin, was the earliest commercialized vinyl chloride-based copolymer resin, and was first developed and produced in 1929 in Germany and the United states. The common preparation methods of the vinyl chloride-vinyl acetate copolymer resin include 4 methods of suspension polymerization, emulsion polymerization, solution polymerization and microsuspension polymerization, wherein suspension polymerization is the most important production method. The chlorine-vinegar copolymer resin is researched only in the sixth and seventies of the last century in China. The production of the copolymer resin by Shanghai chlor-alkali chemical plant, Beijing chemical plant II, Nantong resin plant and other units is carried out successively. However, the vinyl chloride-vinyl acetate copolymer produced in China has a large difference from products abroad in the aspects of solubility, cohesiveness, particle shape, solution viscosity stability and the like, the comprehensive performance is still to be improved, the vinyl chloride-vinyl acetate copolymer mainly meets the low-end market, and the high-end markets of coatings, printing inks and the like are always dependent on the import.
In order to improve the quality of vinyl chloride-vinyl acetate produced in China, a great deal of research is carried out by a plurality of domestic scholars aiming at the preparation process of the vinyl chloride-vinyl acetate copolymer resin and certain effect is obtained, for example, a composite initiator system is adopted to solve the tail warping phenomenon appearing at the later stage of the copolymerization reaction, and a composite dispersant system is adopted to improve the regularity and the granularity of the vinyl chloride-vinyl acetate copolymer resin; the VCM is supplemented for several times to improve the comprehensive performance of the chlorine-vinegar copolymer resin; the phenomenon that the vinyl chloride-vinyl acetate resin slurry sticks to the tower is improved by adopting a micro-positive pressure stripping mode. The technological process for obtaining the vinyl chloride-vinyl acetate copolymer resin by the improved method is basically the same, and the vinyl chloride-vinyl acetate copolymer resin is prepared by the following steps:
adding chloroethylene, vinyl acetate, an initiator, deionized water, a buffering agent, an auxiliary agent and a dispersing agent into a polymerization kettle according to a certain proportion, heating to a reaction temperature, after normal reaction for a period of time, dropping chloroethylene monomer when the pressure of the kettle drops by 0.05MPa, adding a terminating agent to terminate the reaction when the pressure of the reaction kettle drops to 0.5MPa, and discharging. And (3) after the slurry is subjected to steam stripping treatment and centrifugal machine dehydration, conveying the slurry into an airflow drying tower through a screw conveyor, screening the resin dried by a cyclone drying tower into a finished product bin, weighing, packaging and warehousing.
The present inventors have found that, in the currently examined report of the preparation of a vinyl chloride-vinyl acetate copolymer resin, an initiator is always added to the reaction system before the temperature in the reaction vessel reaches a set reaction temperature (60 to 70 ℃), in order to sufficiently mix it with other components before initiating the reaction, and it is widely recognized that this manner (i.e., the manner in which the initiator is sufficiently mixed with the reactants before initiating the reaction) is more advantageous for the reaction of the vinyl chloride-vinyl acetate copolymer resin. However, this is not the case, and it is found through experiments that the mode of adding the initiator later (adding the initiator after the temperature of the reaction system is raised to the set reaction temperature) is more favorable for improving the comprehensive performance of the vinyl chloride-vinyl acetate copolymer resin. Because the initiator in the reaction system is decomposed when reaching 30 ℃, the free radical copolymerization is initiated to generate the copolymer with ultra-high molecular weight, the molecular weight distribution range of the reaction product, namely the vinyl chloride-vinyl acetate copolymer resin, is influenced by the reaction, and the solubility of the product in the ester organic solvent is also influenced.
Disclosure of Invention
Aiming at the problems in the prior art, the technical problems to be solved by the invention are as follows: the chloro-acetic copolymer resin obtained by the conventional method inevitably contains some ultrahigh molecular weight copolymer insoluble substances, which can influence the solubility of the chloro-acetic resin in ester organic solvents.
The technical scheme adopted by the invention for solving the technical problems is as follows: the invention provides a method for preparing a vinyl chloride-vinyl acetate copolymer, which comprises the following steps:
(1) preparing 82-85 parts of vinyl chloride, 15-18 parts of vinyl acetate, 0.18-0.22 part of dispersant, 0.46-0.60 part of initiator mixed solution, 150-160 parts of deionized water, 0-0.3 part of chain regulator and 0.1-0.2 part of terminator for later use;
(2) vacuumizing and deoxidizing the reaction kettle, adding all deionized water, a dispersing agent, a chain regulator and vinyl acetate into the closed reaction kettle according to the formula amount, then adding 60% of vinyl chloride according to the formula amount, uniformly stirring, raising the temperature of a reaction system to a set temperature of 60-70 ℃, then adding initiator mixed liquid according to the formula amount, continuously dropwise adding the rest vinyl chloride monomer when the pressure of the reaction kettle is reduced by 0.15-0.25MPa through constant-temperature stirring reaction, continuing the reaction after the dropwise addition is finished, adding a terminator to terminate the reaction until the pressure of the reaction kettle is reduced to 0.2-0.25MPa, and discharging;
(3) and (3) after the slurry is subjected to steam stripping treatment and centrifugal machine dehydration, conveying the slurry into an airflow drying tower by a screw conveyor, drying the slurry by a cyclone drying tower, collecting the slurry by a cyclone separator, and sieving the slurry by a vibrating screen to obtain the chloroethylene-vinyl acetate copolymer powder.
Specifically, the dispersing agent is a composite dispersing agent consisting of polyvinyl alcohol and hydroxypropyl methyl cellulose in a weight ratio of 2:3-3: 2.
Specifically, the initiator is one or a mixture of more than two of bis (3,5, 6-trimethylhexanoyl) peroxide, tert-butyl peroxypivalate and bis (2-ethylhexyl) peroxydicarbonate.
Specifically, the chain regulator is mercaptoethanol and derivatives thereof.
Specifically, the terminator is an ATSC terminator.
Specifically, the initiator mixed solution comprises the following components in parts by weight:
25-30 parts of deionized water
0.5 to 1.0 portion of dispersant
7-10 parts of an initiator.
The dispersant in the initiator mixed solution is a composite dispersant consisting of polyvinyl alcohol and hydroxypropyl methyl cellulose according to the weight ratio of 2:3-3: 2;
the initiator in the initiator mixed solution is a mixture consisting of one or more than two of bis (3,5, 6-trimethyl hexanoyl) peroxide, tert-butyl peroxypivalate and bis (2-ethylhexyl) peroxydicarbonate.
The invention has the beneficial effects that:
(1) the method for preparing the vinyl chloride-vinyl acetate copolymer does not have the decomposition phenomenon of the initiator in the processes of cold stirring and heating of reactants, and avoids the condition that the initiator is decomposed at low temperature in the process of heating a reaction system to initiate side reaction to generate the ultrahigh molecular weight copolymer;
(2) the initial temperature of cold stirring of the raw materials in winter and summer is different, even though the same formula is adopted, the size of suspension liquid drops formed by a suspension method is different, so that the difference of the performances of the vinyl chloride-vinyl acetate copolymer powder obtained in winter and summer is larger, and the consistency of the product quality cannot be ensured.
Detailed Description
The present invention will now be described in further detail.
The vinyl chloride used in the following examples of the present invention was purchased from Xinpu chemical Co., Ltd, and had a purity of not less than 99.95%, acetylene of not more than 10ppm, and high boiling substances of not more than 100 ppm.
The vinyl acetate employed in the following examples of the present invention was purchased from china petrochemical shanghai petrochemical company limited and had a purity of 99.0%.
The initiator mixed solution adopted in the following embodiments of the invention is a solution obtained by uniformly mixing 25-30 parts by weight of deionized water, 0.5-1.0 part by weight of dispersant and 7-10 parts by weight of initiator in a container.
Example 1
A method of preparing a vinyl chloride-vinyl acetate copolymer comprising the steps of:
(1) preparing 85 parts of vinyl chloride, 15 parts of vinyl acetate, 0.18 part of dispersant, 0.46 part of initiator mixed solution, 150 parts of deionized water and 0.12 part of terminator for standby; the dispersing agent is a composite dispersing agent consisting of polyvinyl alcohol and hydroxypropyl methyl cellulose according to the weight ratio of 2: 3; the initiator is bis (3,5, 6-trimethylhexanoyl) peroxide; the terminator is an ATSC terminator; the initiator mixed solution is obtained by uniformly mixing 25 parts of deionized water, 0.5 part of dispersant and 7 parts of initiator in a container.
(2) Vacuumizing and deoxidizing the reaction kettle, adding all deionized water, a dispersing agent and vinyl acetate into the reaction kettle according to the formula amount, stirring at the stirring speed of 150rpm for 20min, then adding 60% of formula amount of vinyl chloride, uniformly stirring, raising the temperature of a reaction system to 63.5 ℃, then adding a formula amount of initiator mixed solution, stirring at a constant temperature for reaction until the pressure of the reaction kettle is reduced by 0.15MPa, dropwise adding the rest vinyl chloride monomer, after dropwise adding is finished, reacting until the pressure of the reaction kettle is reduced to 0.25MPa, adding a terminator to terminate the reaction, and discharging;
(3) and (3) after the slurry is subjected to steam stripping treatment and centrifugal machine dehydration, conveying the slurry into an airflow drying tower by a screw conveyor, and drying the slurry by a cyclone drying tower to obtain the chloroethylene-vinyl acetate copolymer powder.
Example 2
A method of preparing a vinyl chloride-vinyl acetate copolymer comprising the steps of:
(1) preparing 85 parts of vinyl chloride, 15 parts of vinyl acetate, 0.20 part of dispersant, 0.58 part of initiator mixed solution, 160 parts of deionized water, 0.27 part of chain regulator and 0.15 part of terminator for later use; the dispersing agent is a composite dispersing agent consisting of polyvinyl alcohol and hydroxypropyl methyl cellulose according to the weight ratio of 1: 1; the initiator is tert-butyl peroxypivalate; the chain regulator is mercaptoethanol; the terminator is an ATSC terminator; the initiator mixed solution is obtained by uniformly mixing 30 parts of deionized water, 1.0 part of dispersant and 10 parts of initiator in a container.
(2) Vacuumizing and deoxidizing the reaction kettle, adding all deionized water, a dispersing agent and vinyl acetate into the reaction kettle according to the formula amount, stirring at the stirring speed of 150rpm for 30min, then adding 60% of formula amount of vinyl chloride, uniformly stirring, raising the temperature of a reaction system to a set temperature of 65 ℃, then adding a formula amount of initiator mixed solution, stirring at a constant temperature for reaction until the pressure of the reaction kettle is reduced by 0.15MPa, dropwise adding the rest vinyl chloride monomer, after dropwise adding is finished, reacting until the pressure of the reaction kettle is reduced to 0.20MPa, adding a terminator to terminate the reaction, and discharging;
(3) and (3) after the slurry is subjected to steam stripping treatment and centrifugal machine dehydration, conveying the slurry into an airflow drying tower by a screw conveyor, and drying the slurry by a cyclone drying tower to obtain the chloroethylene-vinyl acetate copolymer powder.
Example 3
A method of preparing a vinyl chloride-vinyl acetate copolymer comprising the steps of:
(1) preparing 82 parts of vinyl chloride, 18 parts of vinyl acetate, 0.22 part of dispersant, 0.58 part of initiator mixed solution, 160 parts of deionized water, 0.1 part of chain regulator and 0.2 part of terminator for later use; the dispersing agent is a composite dispersing agent consisting of polyvinyl alcohol and hydroxypropyl methyl cellulose according to the weight ratio of 3: 2; the initiator is di (2-ethylhexyl) peroxydicarbonate; the chain regulator is ethyl thioglycolate; the terminator is an ATSC terminator; the initiator mixed solution is obtained by uniformly mixing 30 parts of deionized water, 1.0 part of dispersant and 8 parts of initiator in a container.
(2) Vacuumizing and deoxidizing the reaction kettle, adding all deionized water, a dispersing agent and vinyl acetate into the reaction kettle according to the formula amount, stirring at the stirring speed of 150rpm for 20min, then adding 60% of formula amount of vinyl chloride, uniformly stirring, raising the temperature of a reaction system to the set temperature of 61.5 ℃, then adding the formula amount of initiator mixed solution, stirring at constant temperature for reaction until the pressure of the reaction kettle is reduced by 0.25MPa, dropwise adding the rest vinyl chloride monomer, after dropwise adding is finished, reacting until the pressure of the reaction kettle is reduced to 0.25MPa, adding a terminator to terminate the reaction, and discharging;
(3) and (3) after the slurry is subjected to steam stripping treatment and centrifugal machine dehydration, conveying the slurry into an airflow drying tower by a screw conveyor, and drying the slurry by a cyclone drying tower to obtain the chloroethylene-vinyl acetate copolymer powder.
Comparative example 1 the same as example 1 except that in comparative example 1, the initiator mixture was added to the reaction vessel together with the formulated amount of deionized water, dispersant, vinyl acetate and 60% of the formulated amount of vinyl chloride and stirred uniformly before the temperature of the reaction system was raised.
Comparative example 2 the same as example 2, except that in comparative example 2, the initiator mixture was added to the reaction vessel together with the formulated amount of deionized water, dispersant, vinyl acetate and 60% of the formulated amount of vinyl chloride and stirred uniformly before the temperature of the reaction system was raised.
Comparative example 3 the same as example 3, except that in comparative example 3, the initiator mixture was added to the reaction vessel together with the formulated amount of deionized water, dispersant, vinyl acetate and 60% of the formulated amount of vinyl chloride and stirred uniformly before the temperature of the reaction system was raised.
And (3) performance testing:
(1) vinyl acetate content: referring to GB9347-88, 1g of vinyl chloride-vinyl acetate copolymer powder (accurate to 1mg) is weighed into a 100mL conical flask, 25mL of acetone is added by a pipette, the sample is dissolved completely by gentle shaking, 2-3 drops of 0.5 thymol blue reagent are added, and the solution is titrated to blue with KOH-methanol solution (keeping 10s-30s constant). A blank measurement was carried out in the same manner, and the content of the esterified substance in the sample was calculated.
When using 0.05N sulfuric acid and silver nitrate standard solutions, the percentage of vinyl acetate (wt%) is calculated as follows:
the mass percent (wt%) of the vinyl acetate is 0.4304 (V1-V2-V3)/m;
in the above formula, V1-the volume of sulfuric acid standard solution consumed in the blank titration, mL;
v2 — volume of sulfuric acid standard solution consumed in sample titration, mL;
v3-volume of silver nitrate standard solution consumed in sample titration, mL;
m-mass of sample, g.
(2) Sieving ratio (40 mesh): refer to the national standard GB/T2916. After sieving a certain amount (25 +/-0.1) g of chloroethylene-vinyl acetate copolymer powder on a mechanical vibrating sieve for 20min, weighing the mass of the resin remained on a sieve with a specified sieve pore (40 meshes), wherein the ratio of the mass to the total mass of the resin is expressed in weight percent, and the sieving rate of the sieve pore is obtained.
(3) Clarity and insoluble content of the solution: 4g of vinyl chloride-vinyl acetate copolymer powder (exactly 1mg) were weighed into a 100mL Erlenmeyer flask, and 20g of ethyl acetate was added by a pipette and shaken gently for 30min, so that the sample was dissolved sufficiently. The less floc and the less precipitate in the solution, the better the clarity and the better the transparency; clarity is represented by the "+" amount, the more "plus" the better the clarity, the more fully the resin is dissolved.
Refluxing the solution at 25 deg.C for 24hr with filter paper, drying the insoluble substance in the filter paper, weighing, and mixing with 4g of chloroethylene-vinyl acetate copolymer powder to obtain insoluble substance content (wt%).
(4) Glass transition temperature: METTLER DSC3, measured under nitrogen atmosphere, at a temperature rise rate of 20 ℃/min, Mettler corporation.
(5) And (3) detecting the molecular weight and the distribution of the vinyl chloride-vinyl acetate copolymer: GPC1260, Agilent, USA.
The specific test results of the vinyl chloride-vinyl acetate copolymer pellets obtained in examples 1 to 3 and comparative examples 1 to 3 are shown in Table 1.
TABLE 1
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (6)
1. A method for preparing a vinyl chloride-vinyl acetate copolymer, comprising the steps of:
(1) preparing 82-85 parts of vinyl chloride, 15-18 parts of vinyl acetate, 0.18-0.22 part of dispersant, 0.46-0.60 part of initiator mixed solution, 150-160 parts of deionized water, 0-0.3 part of chain regulator and 0.1-0.2 part of terminator for later use;
(2) vacuumizing and deoxidizing the reaction kettle, adding all deionized water, a dispersing agent, a chain regulator and vinyl acetate into the closed reaction kettle according to the formula amount, then adding 60% of vinyl chloride according to the formula amount, uniformly stirring, raising the temperature of a reaction system to a set temperature of 60-70 ℃, then adding initiator mixed liquid according to the formula amount, continuously dropwise adding the rest vinyl chloride monomer when the pressure of the reaction kettle is reduced by 0.15-0.25MPa by constant-temperature stirring reaction, continuing the reaction after the dropwise addition is finished, adding a terminator to terminate the reaction until the pressure of the reaction kettle is reduced to 0.2-0.25MPa, and discharging;
(3) and (3) after the slurry is subjected to steam stripping treatment and centrifugal machine dehydration, conveying the slurry into an airflow drying tower by a screw conveyor, drying the slurry by a cyclone drying tower, collecting the slurry by a cyclone separator, and sieving the slurry by a vibrating screen to obtain the chloroethylene-vinyl acetate copolymer powder.
2. The method of claim 1, wherein the dispersant is a composite dispersant consisting of polyvinyl alcohol and hydroxypropylmethyl cellulose at a weight ratio of 2:3 to 3: 2.
3. The method of claim 1, wherein the initiator is one or more selected from the group consisting of di (3,5, 6-trimethylhexanoyl) peroxide, t-butyl peroxypivalate and di (2-ethylhexyl) peroxydicarbonate.
4. The method of claim 1, wherein the chain regulator is mercaptoethanol and its derivatives.
5. The method of claim 1, wherein the terminator is an ATSC terminator.
6. The method of claim 1, wherein the initiator mixture comprises the following components in parts by weight:
25-30 parts of deionized water
0.5 to 1.0 portion of dispersant
7-10 parts of an initiator.
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CN116041603A (en) * | 2023-01-16 | 2023-05-02 | 陕西北元化工集团股份有限公司 | Suspension polymerization production method of medium-high content vinyl chloride-vinyl acetate copolymer resin |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1809595A (en) * | 2003-06-20 | 2006-07-26 | 阿克佐诺贝尔股份有限公司 | Polymerization process involving the dosing initiators |
CN101638449A (en) * | 2008-07-30 | 2010-02-03 | 沈阳欧陆科技发展有限公司 | Method for preparing low-viscosity polyvinyl chloride paste |
CN105814098A (en) * | 2013-11-28 | 2016-07-27 | 韩化石油化学株式会社 | Method for preparing vinyl chloride-based resin |
CN109627372A (en) * | 2018-12-20 | 2019-04-16 | 内蒙古掌迈环保新材科技有限公司 | The method of homogeneous solution polymerization method production binary vinyl chloride-vinyl acetate resin |
CN113372480A (en) * | 2021-06-10 | 2021-09-10 | 泰州市正大化工有限公司 | Preparation method of high-viscosity vinyl chloride-vinyl acetate copolymer |
-
2021
- 2021-11-23 CN CN202111390470.XA patent/CN114057927A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1809595A (en) * | 2003-06-20 | 2006-07-26 | 阿克佐诺贝尔股份有限公司 | Polymerization process involving the dosing initiators |
CN101638449A (en) * | 2008-07-30 | 2010-02-03 | 沈阳欧陆科技发展有限公司 | Method for preparing low-viscosity polyvinyl chloride paste |
CN105814098A (en) * | 2013-11-28 | 2016-07-27 | 韩化石油化学株式会社 | Method for preparing vinyl chloride-based resin |
CN109627372A (en) * | 2018-12-20 | 2019-04-16 | 内蒙古掌迈环保新材科技有限公司 | The method of homogeneous solution polymerization method production binary vinyl chloride-vinyl acetate resin |
CN113372480A (en) * | 2021-06-10 | 2021-09-10 | 泰州市正大化工有限公司 | Preparation method of high-viscosity vinyl chloride-vinyl acetate copolymer |
Non-Patent Citations (1)
Title |
---|
宋晓玲等: "氯乙烯-醋酸乙烯悬浮共聚树脂的开发与研究", 《聚氯乙烯》 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116041603A (en) * | 2023-01-16 | 2023-05-02 | 陕西北元化工集团股份有限公司 | Suspension polymerization production method of medium-high content vinyl chloride-vinyl acetate copolymer resin |
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