CN106349417A - Method for removing volatile components from ethylene-vinyl acetate copolymer solution - Google Patents
Method for removing volatile components from ethylene-vinyl acetate copolymer solution Download PDFInfo
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- CN106349417A CN106349417A CN201510420313.7A CN201510420313A CN106349417A CN 106349417 A CN106349417 A CN 106349417A CN 201510420313 A CN201510420313 A CN 201510420313A CN 106349417 A CN106349417 A CN 106349417A
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Abstract
The invention discloses a method for removing a solvent from an ethylene-vinyl acetate copolymer solution. The method comprises the following steps: 1) obtaining the ethylene-vinyl acetate copolymer solution via solution copolymerization, 2) mixing the copolymer solution with water at a certain temperature to form a mixed solution, and injecting water vapor to be intensively mixed with the mixed solution to form mixed gas containing water and the solvent, and a mixture containing colloidal particles and the water, and 3) performing solid-liquid separation on the mixture containing the colloidal particles and the water to form an ethylene-vinyl acetate copolymer. With the adoption of the method, volatile components in the colloidal particles can be removed at a high level, so that the content of the volatile components in the polymer colloidal particles is reduced, and advantageous conditions are created for post processing of the polymer colloidal particles.
Description
Technical field
The present invention relates to polyreaction field is and in particular to a kind of removing vinyl-vinyl acetate copolymer solution is waved
The method of the property sent out component.The invention still further relates to volatile component in removing vinyl-vinyl acetate copolymer solution
Equipment.
Background technology
Vinyl-vinyl acetate copolymer (eva) is a kind of very high random copolymer of degree of branching, by non-polar
Vinyl monomer (e) is formed with highly polar vinyl acetate monomer (vac) copolymerization, is that topmost ethylene derivative is common
One of polymers.Eva has excellent low temperature resistant and environmental stress cracking resistance, has good optics simultaneously
Performance, nontoxic, it is widely used in packaging film, agricultural film, electric wire, shoemaking, injection extrude product, too
The fields such as sun energy.
United States Patent (USP) us 4485225 and European patent ep 136559 describe for ethylene and vinyl acetate
, radical initiator and in the presence of carry out copolymerization process.This reacts anti-for gas-liquid two-phase copolymerization
Should, vinyl monomer is present in gas phase, and vinyl acetate, initiator and solution are present in liquid phase.After reaction terminates,
Obtain ethane-acetic acid ethyenyl ester solution.
In actual applications, ethane-acetic acid ethyenyl ester solution can obtain ethylene-vinyl alcohol copolymer with after saponification,
Directly can also be applied in the middle of commercial production in the form of a solution, but in most cases, need to carry out solvent
Removing and recovery, thus obtain ethane-acetic acid ethyenyl ester micelle or blob of viscose.
At present, the method for removing solvent in polymer solution in commercial production, it usually needs behaviour combined by many kettles
Make, technological process length, complex operation, high cost, and the removal efficiency of solvent is not high.And it is directed to ethylene-acetate
In vinyl ester copolymers production process, the method for volatile component removing and technique are also rarely reported.
Content of the invention
Present invention aims to deficiency of the prior art, provide a kind of removing ethane-acetic acid ethyenyl ester altogether
The method of volatile component in copolymer solution, makes the volatile component in vinyl-vinyl acetate copolymer solution
(solvent and a small amount of unreacted monomer that may be present) can be removed by simple technological process, makes institute
In the dried copolymer obtaining, the content of volatile component is very little, and such as less than 0.02%.The present invention also carries
Supply the equipment used by said method.
According to an aspect of the invention, it is provided volatilizing in a kind of removing vinyl-vinyl acetate copolymer solution
The method of property component, comprises the following steps:
1) pass through solution copolymerization, obtain vinyl-vinyl acetate copolymer solution；
2) water of the solution of described copolymer and uniform temperature is mixed to get mixed liquor in container, to container
Inside it is passed through vapor, described vapor is mixed with described mixed liquor, then obtain comprising the gaseous mixture of water and solvent
Body, and comprise the mixture of copolymer micelle and water；
3) mixture of described micelle and water is carried out solid-liquid separation, obtain the ethane-acetic acid ethyenyl ester of drying altogether
Polymers.
According to method of the present invention, vapor therein can provide heat and conveying power, promotes system
Temperature rise, solvent evaporation and promote mixed gas discharge, such as promote solvent composition to strip and discharge, glue
Size separation goes out；And then, make the volatile component in micelle reach high standard removing by the method in the present invention, from
And reduce the volatile component content in polymer billet, it is that the post-production of polymer billet creates favourable bar
Part.
According to a specific embodiment of the inventive method, the water of uniform temperature refers to that the temperature of water should be not less than 60
℃.For the water of described uniform temperature, its temperature improves and is conducive to saving vapor, with the rising of temperature,
Heating energy consumption increases, and the heat resistant requirements of equipment are improved.Preferably in the water of uniform temperature, the temperature of water is not less than 80
DEG C, more preferably 80-90 DEG C.
According to another specific embodiment of the inventive method, the water of described uniform temperature and the solution of copolymer
Volume ratio is more than 1:1, thus ensure that the micelle being formed is had with the water of described uniform temperature sufficiently contacting, and protects
Card micelle will not form large-scale micelle after separating out, and be wound around stirring paddle and block discharge pipe.If a however, constant temperature
The consumption of the water of degree is excessive, will increase considerably the energy consumption of heating and follow-up separation process, leads to production cost
Above-mentioned.Preferably the water of uniform temperature and the volume ratio of the solution of copolymer are more than 1:1 to 5:1, more preferably
1.5:1-4:1.
According to another specific embodiment of the inventive method, the solvent used in described solution copolymerization is fat
Alcohol, preferably carbon atom are not more than 4 fatty alcohol, more preferably at least in methanol, ethanol, propanol and butanol
Kind.Consolidating in the copolymer solution that the solid content in described copolymer solution can obtain for conventional polymerisation in solution contains
Amount, here is omitted.
In a specific embodiment, in described step 2) in, described copolymer solution spurts into a constant temperature
In the water of degree, obtain mixed liquor.By the way of injection, the drop that injection is formed can control the size of micelle,
Thus being conducive to further avoiding the formation of micelle.Form the removal that big micelle is unfavorable for wherein volatile component.
According to the present invention, described vapor can (1) provide heat for spraying into the solution in condensing field so as to
Reach stripping temperature；(2) provide the latent heat of vaporization for the evaporation of volatile component；(3) become gas for evaporation
Volatile component provide conveying power, promote its discharge.Preferably control vapor flow and steam so that being passed through water
The temperature control in container after gas, at 85-100 DEG C, so, both ensure that operation temperature was higher than the boiling of volatile matters
Point, is conducive to volatile matters to gasify, decreases the consumption of steam simultaneously, save energy consumption.Preferably control described common
The time of staying of the solution of polymers is 10-60 minute, and preferably 30-40 minute is conducive to micelle to fill in water
The precipitation dividing.In a specific embodiment, described container is coacervation device.
According to another specific embodiment of the inventive method, in described mixed gas and/or described mixture, also
Unreacted monomer can be comprised, described unreacted monomer is divided from described mixed gas and/or described mixture
Separate out, be back to described step 1), carry out copolyreaction, thus realizing recycling of unreacted monomer,
Discharge is avoided to pollute, and reduces cost and material consumption.
According to another specific embodiment of the inventive method, the solvent in described mixed gas and water are carried out point
It is back to step 1 from, the solvent obtaining and water respectively) and 2).At the same time it can also by step 3) in separate
Water out is back to step 2).By aforesaid operations, realize solvent and water are recycled, it is to avoid row
Put and pollute, and reduces cost and material consumption.
The method being provided according to the present invention, just can remove vinyl-vinyl acetate copolymer by simple technique
Solvent in solution, makes remaining volatile matters in polymer obtain high standard removing, thus reducing polymer latex
Volatile component in grain.In a specific example, can containing the volatile component in polymer billet
Amount decreases below 0.02%.Meanwhile, the method being provided according to the present invention, can be by solvent, unreacted monomer
And water continues cycling through utilization, reduce energy consumption and material consumption, thus also reducing production cost.
According to another aspect of the present invention, additionally provide a kind of removing vinyl-vinyl acetate copolymer solution
The equipment of middle volatile component, comprising: coacervation device, is provided with rabbling mechanism in it, is provided with and uses respectively in the middle part of it
In the first import and second import of the water introducing copolymer solution and uniform temperature, its bottom is provided with for introducing
The triple feed inlet of vapor and the first outlet drawing the mixture containing micelle and water, its top is provided with extraction containing molten
The second outlet of the mixed gas of agent and water；The equipment for separating liquid from solid being connected with described coacervation device, is gone out from first
The described mixture that mouth is drawn enters described equipment for separating liquid from solid, obtains the copolymer micelle of drying.
According to equipment of the present invention, the position of preferably described first import is higher than the position of the second import.Excellent
Select the liquid level position in described coacervation device between the position of the position of the first import and the second import.Pass through
Above-mentioned setting, is conducive to the blending of the copolymer solution from the first import inflow and the water of uniform temperature, it is to avoid the
One entrance solution is too fast with water to be contacted, and forms micelle, blocks the first import.
According to another specific embodiment of the present invention, the pressure of described first entrance is more than described coacervation device
Interior pressure, thus be conducive to relying on pressure differential to promote copolymer solution to flow to coacervation device；And first import
Place can assume spray regime by copolymer solution, and the drop of formation can control the size of micelle, it is to avoid forms micelle,
It is wound around stirring paddle.Method in the present invention can be carried out continuously, and also can intermittently carry out.
According to the equipment of the present invention, the described vinyl-vinyl acetate copolymer solution being obtained by solution copolymerization is led to
Cross the first import and introduce described coacervation device, with the uniform temperature introducing from the second import in described coacervation device
Water mixing, preferably described copolymer solution be in spray regime.From the triple feed inlet of coacervation device bottom, water is steamed
Gas introduces coacervation device, by controlling two of vapor, controls the temperature in coacervation device, preferably described solidifying
The operation temperature of poly- device controls at 85-100 DEG C.So, both ensure that operation temperature was higher than the boiling point of volatile matters,
Be conducive to volatile matters to gasify, decrease the consumption of steam simultaneously, save energy consumption.Described copolymer solution is solidifying
The time of staying in poly- device controls in 10-60 minute, and preferably 30-40 minute is conducive to micelle fully to analyse
Go out.
According to the equipment of the present invention, vapor that the triple feed inlet from the bottom of coacervation device introduces is by coacervation device
The mixed liquor heat temperature raising of interior vinyl-vinyl acetate copolymer solution and the water of uniform temperature so as in molten
Agent component strips, and micelle separates out, and the mixed gas containing solvent and vapor pass through the second of coacervation device top
Outlet is discharged, and the mixture containing micelle and water is drawn by the first outlet positioned at described coacervation device bottom.
According to a specific embodiment of equipment of the present invention, the instantiation of described equipment for separating liquid from solid can
Including dehydration and vibration sieve, screw expansion dryer and baking oven etc..
According to the method and apparatus of solvent in the removing vinyl-vinyl acetate copolymer solution that the present invention provides, energy
The volatile component in copolymer solution, the drying obtained by making enough is removed by a kind of simple technique and equipment
In copolymer afterwards, the content of volatile component is very little, and such as less than 0.02%.
Brief description
The flow chart that Fig. 1 removes volatile component in vinyl-vinyl acetate copolymer solution for the present invention.
Specific embodiment
With reference to the accompanying drawings and examples the present invention is described further, but does not cause to protect model to the present invention
Any restriction enclosed
Refer to the attached drawing 1, vinyl-vinyl acetate copolymer solution 1 and hot water 2 are separately added into coacervation device 4,
The steam 3 entering coacervation device 4 is heated intensification, the volatility in ethane-acetic acid ethyenyl ester solution 2 simultaneously
Component is stripped out.The glue grain 6 of removing volatile component is poly- with wet by hot water through dehydration and vibration sieve 10
Compound micelle 7 is separately.Wet polymer micelle 7 obtains wet polymer micelle 8 through screw extruding dewaterer 12；
It is dehydrated further through screw expansion dryer 13 again；Finally enter in baking oven 14 and be dried, you can obtain drying
Vinyl-vinyl acetate copolymer micelle 11.Steam 5 that coacervation device 4 is isolated is through condensation, and de-
Through separating, solvent, unreacted monomer and water are able to circulation to be made the water that water vibrosieve 10 is separated
Use (not shown).
Embodiment 1
The flow chart ginseng of volatile component in the vinyl-vinyl acetate copolymer solution with methanol as solvent for the removing
See accompanying drawing 1.
With water pump, 80 DEG C of hot water are passed through in coacervation device；With methanol as solvent, solid content is about 30% ethylene
- vinyl acetate solution is passed through in coacervation device；Hot water is 3:1 with the volume ratio of ethane-acetic acid ethyenyl ester solution；
Steam is passed through coacervation device, by the control of steam flow, maintains the operation temperature of coacervation device to be 85 DEG C；
Volatile component in ethane-acetic acid ethyenyl ester solution is stripped out.Ethane-acetic acid ethyenyl ester solution is controlled to coagulate
The time of staying of poly- device is 30 minutes it is ensured that micelle sufficiently separates out in water.Removing volatile component
Hot water is separated with wet polymer micelle by glue grain through dehydration and vibration sieve, and now the volatile component in micelle contains
Amount is about 0.3%.Wet polymer micelle is dehydrated devolatilization through screw extruding dewaterer；It is dried through screw expansion again
Machine is dehydrated devolatilization further；Finally enter in baking oven and be dried, you can obtain the ethylene-vinyl acetate c of drying
Thing micelle, now the volatile component content in micelle is less than 0.02%.
Embodiment 2
The flow chart of volatile component in the vinyl-vinyl acetate copolymer solution with the tert-butyl alcohol as solvent for the removing
Referring to accompanying drawing 1.With water pump, 90 DEG C of hot water are passed through in coacervation device；With the tert-butyl alcohol as solvent, solid content is about
30% ethane-acetic acid ethyenyl ester solution is passed through in coacervation device；Hot water and the body of ethane-acetic acid ethyenyl ester solution
Long-pending ratio is 2:1；Steam is passed through coacervation device, by the control of steam flow, maintains the operation of coacervation device
Temperature is 95 DEG C；Volatile component in ethane-acetic acid ethyenyl ester solution is stripped out.Control ethylene-acetate
The time of staying of vinyl acetate solution casting device is 40 minutes it is ensured that micelle sufficiently separates out in water.Removing
Hot water is separated with wet polymer micelle by the glue grain of volatile component through dehydration and vibration sieve, now in micelle
Volatile component content is about 0.5%.Wet polymer micelle is dehydrated devolatilization through screw extruding dewaterer；Pass through again
Screw expansion dryer is dehydrated devolatilization further；Finally enter in baking oven be dried, you can obtain drying ethylene-
Vinyl acetate copolymer micelle, now the volatile component content in micelle is less than 0.02%.
By above content it is known that the method and apparatus providing according to the present invention, can fully remove polymerization
Volatile component in thing micelle, and process is simple, easy to operate, and low production cost.According to the present invention, carry
Supply a kind of minimizing technology of volatile component in solution for vinyl-vinyl acetate copolymer.
It should be noted that embodiment described above is only used for explaining the present invention, do not constitute to the present invention's
Any restriction.By referring to exemplary embodiments, invention has been described, it should be appreciated that wherein used
Word is descriptive and explanatory vocabulary, rather than limited vocabulary.Can be by regulation in the claims in the present invention
In the range of the present invention is modified, and in without departing substantially from scope and spirit of the present invention, the present invention is carried out
Revision.Although the present invention described in it is related to specific method, material and embodiment, it is not intended that
The present invention is limited to wherein disclosed particular case, and on the contrary, the present invention can be extended to other and all has identical function
Methods and applications.
Claims (10)
1. a kind of method removing volatile component in vinyl-vinyl acetate copolymer solution, walks including following
Rapid:
1) pass through solution copolymerization, obtain vinyl-vinyl acetate copolymer solution；
2) water of described copolymer solution and uniform temperature is mixed to get mixed liquor in container, into container
It is passed through vapor, described vapor is mixed with described mixed liquor, then obtain comprising the mixed gas of water and solvent,
And comprise the mixture of copolymer micelle and water；
3) mixture of described micelle and water is carried out solid-liquid separation, obtain the ethane-acetic acid ethyenyl ester of drying altogether
Polymers.
2. method according to claim 1 is it is characterised in that the water of described uniform temperature and copolymer
The volume ratio of solution is more than 1:1, preferably greater than 1:1 to 5:1, more preferably 1.5:1 to 4:1.
3. method according to claim 1 and 2 is it is characterised in that the water of described uniform temperature refers to water
Temperature should be not less than 60 DEG C, preferably not less than 80 DEG C, more preferably 80-90 DEG C.
4. the method according to any one in claim 1-3 is it is characterised in that in described solution copolymerization
The solvent being used be fatty alcohol, preferably carbon atom be not more than 4 fatty alcohol, more preferably methanol, ethanol, third
At least one in alcohol and butanol；And/or in step 2) in, the solution of described copolymer is spurted into described one
In the water of constant temperature degree, it is mixed to get mixed liquor with the water of uniform temperature.
5. the method according to any one in claim 1-4 it is characterised in that control vapor flow,
So that the temperature control being passed through in container after vapor is at 85-100 DEG C；And/or control the solution of described copolymer to exist
The time of staying in container is 10-60 minute, preferably 30-40 minute.
6. the method according to any one in claim 1-5 it is characterised in that described mixed gas and
/ or described mixture in comprise unreacted monomer, by described unreacted monomer from described mixed gas and/or
Separate in described mixture, be back to described step 1), carry out copolyreaction.
7. the method according to any one in claim 1-6 is it is characterised in that by described mixed gas
In solvent and water carry out separating, the solvent obtaining and water are back to step 1 respectively) and 2)；And/or will walk
The water separated in rapid 3) is back to step 2).
8. one kind is using any one methods described removing vinyl-vinyl acetate copolymer in claim 1-7
The equipment of volatile component in solution, comprising:
Coacervation device, is provided with rabbling mechanism in it, is provided with and is respectively used to introduce copolymer solution and certain in the middle part of it
First import of the water of temperature and the second import, its bottom is provided with triple feed inlet and extraction for introducing vapor
First outlet containing micelle and the mixture of water, its top is provided with draws the second of the mixed gas containing solvent and water
Outlet；
The equipment for separating liquid from solid being connected with described coacervation device, the described mixture drawn from first outlet enters institute
State equipment for separating liquid from solid, obtain the vinyl-vinyl acetate copolymer of drying.
9. equipment according to claim 8 is it is characterised in that the position of described first import is higher than second
The position of import；And/or, the liquid level position in described coacervation device is between the position of the first import and the second import
Position between；And/or, the pressure of described first import is higher than the pressure in described coacervation device.
10. equipment according to claim 8 or claim 9 is it is characterised in that the operation temperature of described coacervation device
Degree controls at 85-100 DEG C；And/or the described copolymer solution time of staying in coacervation device controls in 10-60
Minute, preferably 30-40 minute.
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| CN201510420313.7A CN106349417B (en) | 2015-07-16 | 2015-07-16 | The method for removing volatile component in vinyl-vinyl acetate copolymer solution |
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| CN201510420313.7A CN106349417B (en) | 2015-07-16 | 2015-07-16 | The method for removing volatile component in vinyl-vinyl acetate copolymer solution |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114316090A (en) * | 2020-09-29 | 2022-04-12 | 北京诺维新材科技有限公司 | Low-solvent-residue polymer and preparation method thereof |
Citations (2)
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|---|---|---|---|---|
| CN102549025A (en) * | 2009-10-07 | 2012-07-04 | 日本合成化学工业株式会社 | Process for producing ethylene/vinyl alcohol copolymer |
| CN103626910A (en) * | 2013-11-29 | 2014-03-12 | 西南化工研究设计院有限公司 | Solid ethylene-vinyl acetate copolymer and preparation method thereof |
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2015
- 2015-07-16 CN CN201510420313.7A patent/CN106349417B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102549025A (en) * | 2009-10-07 | 2012-07-04 | 日本合成化学工业株式会社 | Process for producing ethylene/vinyl alcohol copolymer |
| CN103626910A (en) * | 2013-11-29 | 2014-03-12 | 西南化工研究设计院有限公司 | Solid ethylene-vinyl acetate copolymer and preparation method thereof |
Non-Patent Citations (2)
| Title |
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| 山西省化工研究所编: "《塑料橡胶加工助剂（第二版）》", 31 October 2002 * |
| 高莉萍等: "聚合物溶液后处理技术", 《兰化科技》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114316090A (en) * | 2020-09-29 | 2022-04-12 | 北京诺维新材科技有限公司 | Low-solvent-residue polymer and preparation method thereof |
| CN114316090B (en) * | 2020-09-29 | 2023-06-30 | 北京诺维新材科技有限公司 | Polymer with low solvent residue and preparation method thereof |
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