CN1010679B - Compoundedinhibitor of polymerization for methacrylic acid and esters thereof - Google Patents
Compoundedinhibitor of polymerization for methacrylic acid and esters thereofInfo
- Publication number
- CN1010679B CN1010679B CN86103840A CN86103840A CN1010679B CN 1010679 B CN1010679 B CN 1010679B CN 86103840 A CN86103840 A CN 86103840A CN 86103840 A CN86103840 A CN 86103840A CN 1010679 B CN1010679 B CN 1010679B
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- methacrylic acid
- polymerization inhibitor
- tmhpo
- tert
- stopper
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- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The present invention relates to a bicomponent composite polymerization inhibitor for methacrylic acid and esters thereof. For searching for a high-efficiency composite polymerization inhibitor with wide temperature application range and low use level for the methacrylic acid and the esters thereof, a nitrogen-oxygen free radical compound is combined with a selected polymerization inhibitor of phenol and amine according to a certain proportion. As the nitrogen-oxygen free radical compound and the selected polymerization inhibitor of phenol and amine generate synergistic effect, compared with an original component inhibitor with the same concentration, the bicomponent composite polymerization inhibitor enhances the inhibitive effect in multiples, and the requirement of an oxygen content in a material system is small in an inhibitive process, so the bicomponent composite polymerization inhibitor is especially suitable for the rectification under vacuum of the monomers of methacrylic acid classes with high boiling point and easy polymerization.
Description
The present invention relates to the composite polymerzation inhibitor of methacrylic acid and ester class thereof.
Methacrylic acid and ester class thereof are of many uses; but because the monomer of methacrylic acid and ester class thereof is very active; in preparation, separation, transporting procedures; because the effect of light, heat, superoxide causes autohemagglutination easily; occluding device; make to produce to be difficult to carry out, especially the polymerization tendency is just stronger under the conditions of high temperature such as rectifying.
Adding stopper is to prevent the polymeric effective means.So far, the stopper of methacrylic acid and ester class thereof has proposed much, and is of a great variety from the single variety to the compound system, but weak point is respectively arranged.For example, the common methacrylic acid and the stopper of ester class thereof have phenols, amine, variable valency metal salt etc.Wherein, phenols, amine stopper must just work in the presence of molecular oxygen, and variable valency metal salt is poorly soluble in system for handling, and under high temperature rectifying situation, their effect is all very poor, so industrial practicality is restricted.Some compound resistance aggressiveness that contain phenols, aminated compounds are, as U.S. Pat 3,666, Resorcinol-phenol of 794-oxygen system, the phenol of Japanese kokai publication sho 52-34606-copper dialkyldithiocarbamate system, the resistance that is used for acrylic monomer is poly-, all need blast molecular oxygen specially, otherwise polymerization inhibition effect descends sharply.
After the sixties, found the new stabilized radical-nitroxyl free radical of a class.2,2,6,6-tetramethyl--4-hydroxy-piperdine nitroxyl free radical (hereinafter to be referred as TMHPO) is one of representative of nitroxyl free radical compounds, this compound is a kind of broad spectrum type high-efficiency polymerization inhibitor, polymerization inhibition effect for methacrylic acid and ester class thereof is very outstanding, has efficiently and does not need advantage such as logical oxygen.For further improving its polymerization inhibition effect, people are once to TMHPO, mix use by a certain percentage with one or more other class stopper, exist synergistic effect between the stopper of discovery TMHPO and some other kind, the polymerization inhibition effect of its composite polymerzation inhibitor also has raising than the TMHPO of single component.The domestic people of having once proposed the TMHPO-benzoquinones and the compound resistance aggressiveness of TMHPO-benzoquinones-thiodiphenylamine is to acrylic acid inhibition; (Zhang Ziyi, Wei Xiuying; " 2; 2; 6; 6-tetramethyl--4-hydroxy-piperdine oxyradical is to the poly-character of acrylic acid efficient resistance " " SCI " Vo1.4; No.2; P.244-246(1983)) point out: when the consumption of TMHPO is 0.1～0.3%(weight of vinylformic acid consumption) time; higher polymerization inhibition effect is arranged; and when the same quinones of TMHPO, when thiodiphenylamine mixes in the proper ratio, can produce synergistic effect.But as the stopper of vinylformic acid and ester class thereof, existing compound oxygen radical of nitrogen and with its compound composite polymerzation inhibitor consumption all than higher, so can not satisfy industrial actual needs, this has just limited being extensive use of of it.
The objective of the invention is to seek a kind of efficient composite polymerzation inhibitor that temperature applicable range is wide, consumption is low that is applicable to methacrylic acid and ester class thereof, thereby make production process can obtain better techno-economic effect.
The present invention is used for the composite polymerzation inhibitor of methacrylic acid (being called for short MAA) and ester class thereof, and it is to be formed by two combination of components of A, B,
The A component is:
2,2,6,6-tetramethyl--4-hydroxy-piperdine nitroxyl free radical (being TMHPO)
The B component is:
(1) N-sec.-propyl-N '-diphenyl-para-phenylene diamine (being called for short 4010NA)
(2) MEHQ (or claiming p methoxy phenol) (being called for short Me HQ)
(3) 2,2 '-methylene radical-two (4-methyl-6-tert butyl phenol) (being called for short 2246)
(4) 4-tert-butyl catechol (being called for short TBC)
The preparation method of composite polymerzation inhibitor of the present invention is: with A component and any uniform mixing that is referred to as in above-mentioned four kinds of compounds of B component, promptly become the composite polymerzation inhibitor of methacrylic acid of the present invention and ester class thereof.The weight ratio of A, B two components can be 0.1～10: change arbitrarily in 1 scope, all have synergistic effect to produce, the size of synergistic effect is relevant with the weight ratio of A, B two components, when the ratio of A and B weight is 1～2: have best polymerization inhibition effect in the time of 1.During use, can select suitable prescription for use according to the price factor of poly-requirement of different resistances and stopper.Because the poly-time of the consumption of composite polymerzation inhibitor of the present invention and resistance all presents good linear relationship in extremely wide scope, can be during use on the historical facts or anecdotes border according to the poly-consumption that requires to regulate stopper of activity, material temperature and the resistance of material, the stopper consumption can be controlled at 10～4000ppm, and its optimum amount scope is at 50～500ppm.
The present invention compares the polymerization inhibition effect height with the stopper of existing methacrylic acid and ester class thereof.The resistance that 4010NA composite polymerzation inhibitor for example: TMHPO 50%(weight) and 50%(weight) is used for methacrylic acid gathers, its poly-time of resistance is when using separately than A or B component, prolong more than 1～3 times, 65%(weight) TMHPO and 35%(weight) the composite polymerzation inhibitor of Me HQ to be used for the resistance of MAA poly-, the poly-time of its resistance is 30 times of Resorcinol.Identical resistance gathers the time, TMHPO in the composite polymerzation inhibitor: consumption only be 1/3～1/2 of pure TMPHO.
Composite polymerzation inhibitor of the present invention must just show synergistic effect in the presence of molecular oxygen, if with this composite polymerzation inhibitor through the decrease temperature crystalline high vacuum, do not have molecular oxygen in the monomer, synergistic effect has not existed.Though the existence of molecular oxygen is the prerequisite that produces synergistic effect, and is very little to the requirement of oxygen concn.Under 15～20 mmhg, molten Jie's oxygen just is enough to guarantee to produce synergistic effect in the monomer, and shows fabulous polymerization inhibition effect.Under the normal pressure, molten Jie's oxygen is too much in the monomer.If blast oxygen, polymerization inhibition effect is descended significantly to monomer.Composite polymerzation inhibitor of the present invention in difference to the visible embodiment 4 of the synergistic effect under the oxygen condition.
Because composite polymerzation inhibitor of the present invention requires very little to oxygen level in the system, so to static state resistance collecting process, system's absolute pressure is in 15～760 mmhg scopes, aforesaid two-pack composite polymerzation inhibitor all produces synergistic effect, and at decompression state, polymerization inhibition effect is better.Therefore, to static state resistance collecting process, as storage, the transportation of methacrylic acid and ester class thereof, if can adopt vacuumize or protected mode reduction system such as nitrogen replacement in oxygen level, then the present invention can show bigger superiority.As for dynamic resistance collecting process, be continuous rectification under vacuum process more than 20 mmhg as absolute pressure, contained oxygen just is enough to guarantee to produce significant synergistic effect in the system, need not to blast specially oxygen or air.
Methacrylic acid-isopropylformic acid (being called for short IBA) binary liquid mixture, because boiling point is close, relative volatility very little (about 1.5), soltion viscosity is big, separate two acid and need more theoretical tray, so the autohemagglutination problem of MAA is more outstanding, sepn process is difficulty quite.Use stopper of the present invention, can solve the two sour separation problems that boiling point only differs from 6.2 ℃ well, autohemagglutination does not take place in the high temperature occasion of rectifying in MAA yet, and system's pressure reduction is stable in the sepn process, and operation is normal.
The present invention compares with the stopper of existing methacrylic acid and ester class thereof, when inhibitor concentration was identical, the polymerization inhibition effect height was under the close situation of polymerization inhibition effect, the consumption of TMPHO is few in the composite polymerzation inhibitor of the present invention, only is 0.005～0.05%(weight of methacrylic acid and ester class thereof).Simultaneously, composite polymerzation inhibitor of the present invention requires very little to oxygen level in the system, so use composite polymerzation inhibitor of the present invention can reduce production costs remarkable in economical benefits; Because TMHPO is nontoxic, thus do not pollute the environment, to hot, oxygen is all very stable; Make also uncomplicated, the institute so that industrial application.
Be embodiments of the invention below.
Some explanation about embodiment:
1. resistance gathers the measuring method of time to various stoppers to MAA:
(1) boiling process: will be dissolved with in 7～9 milliliters of clean glass test tubees of drying of packing into of MAA monomer of initiator benzoyl peroxide (being called for short BPO) and stopper, then test tube is placed water bath with thermostatic control, write down the material automatic boiling or time of oyster white polymkeric substance occurs with stopwatch, promptly be under this condition this kind stopper to the poly-time of the resistance of MAA.
(2) visual method: will be dissolved with in 7～9 milliliters of clean glass test tubees of drying of packing into of monomer of stopper, and insert water bath with thermostatic control, the time of polymkeric substance appears in start-of-record.
(3) vacuum sealing tube method: after glass tube sealing washing lotion, the careful washing and drying of acetone, the monomer that is dissolved with stopper is injected Glass tubing, under vacuum, handle certain hour, seal with alcohol blast burner, insert water bath with thermostatic control, the time of polymkeric substance appears in observation and start-of-record.
2.TMHPO the preparation method:
Used TMHPO is with 2 among the present invention; 2; 6; the orange solid that 6-tetramethyl--4-hydroxy piperidine alcohol and methyl alcohol, water, sodium wolframate, edetate disodium and hydrogen peroxide make under 20 ℃ of conditions; with reference to (Liu Youcheng, Jiang Zhiqin " the synthetic and reaction of the research of nitroxyl free radical (I)-piperidine nitroxide free-radical " " SCI " No.1, P71～76(1980)).This solid normal hexane recrystallization obtains faint yellow needle crystal, 68～70 ℃ of its fusing points, and through chemistry institute of Chinese Academy of Sciences paramagnetic spectrum analysis, purity is bordering on 100%.
3. MAA-IBA solution system is got through oxidation, dehydrogenation, extraction, separation by isobutyric aldehyde among the embodiment 6.It is formed with neutralisation and saponification-bromination method mensuration.MAA and IBA total content are more than 99.4%.
4. used several raw material specification among the embodiment:
The serial number name specification place of production
1 TMHPO: 68～70 ℃ of self-controls of fusing point
54.5～56.0 ℃ of Beijing reagent two factories of 2 TBC fusing points
3 Me HQ chemically pure reagent Beijing reagent two factories
Chemical plant, 4 2246 industrial goods Nanjing
5 4010NA industrial goods are fusing point 〉=chemical plant, 74.5 Nanjing just
6 NN '-hexichol
Chemical plant, base Ursol D industrial goods Nanjing
First fusing point 〉=125.0 ℃
7 Resorcinol chemically pure reagents
8 venus crystals chemically pure reagents
9 MAA purity＞98.5%(bromination method) self-control
10 IBA purity＞99%(neutralisation) self-control
Embodiment 1
The MAA8 gram that is dissolved with 0.6% benzoyl peroxide is added in the test tube of cleaning oven dry with a certain amount of stopper, place 100 ℃ of water-baths, measure the beginning polymeric time with boiling process, the result of the present invention and comparative example is as shown in table 1:
Table 1
Stopper begins polymerization time (second)
Title consumption (ppm)
1 TMHPO· 500
TBC 500 269
Real 2 TMHPO 500
2246 500 328
Execute 3 TMHPO 500
4010NA 500 268
Example 4 TMHPO 500
Me HQ 500 288
1 Resorcinol 1,000 151
Than 2 Me HQ 1,000 162
3 2246 1000 156
Than 4 4010NA 1,000 127
5 N, N '-2 1,000 60
Diphenyl-para-phenylene diamine
Example 6 TBC 1,000 140
Than 7 TMHPO 1,000 240
Than 8 TMHPO 500 170
Example 9 blank 0 23
Embodiment 2
MAA8 gram and a certain amount of stopper are added in the test tube of cleaning oven dry, place 100 ℃ of water-baths, measure the beginning polymeric time with visual method, the present invention and comparative example the results are shown in table 2:
Table 2
Stopper begin polymerization time (hour)
Title consumption (ppm)
Blank 0 0.10
1 TMHPO· 65
Real 4010NA 35 31.00
2 TMHPO· 65
Me HQ 35 32.00
Execute 3 TMHPO 65
2246 35 23.50
4 TMHPO· 50
Example TBC 50 25.00
5 TMHPO· 25
4010NA 25 18.00
6 TMHPO· 100
ME HQ 100 36.70
1 Resorcinol 100 0.80
Than 2 venus crystalss 100 0.65
3 TMHPO· 50 11.30
Than 4 4010NA 50 6.70
5 2246 100 2.50
Example 6 TBC 100 2.00
7 Me HQ 100 5.00
Embodiment 3
The MAA that is added with a certain amount of stopper is inserted tube sealing, be evacuated to overbottom pressure 20 mmhg, kept 15～20 minutes, vacuum seal places 100 ℃ of water-baths, measures the beginning polymeric time with visual method, the results are shown in Table 3:
Table 3
The sequence number stopper begins the polymerization time phenomenon
Title consumption (ppm) (hour)
1 TMHPO 50 48 makes slow progress
Me HQ 50
2 TMHPO 50 44 make slow progress
4010NA 50
3 TMHPO 50 21 make slow progress
Embodiment 4
Measure the influence of oxygen to synergistic effect, (TMHPO and Me HQ) measures four kinds of different oxygen supply situations to composite polymerzation inhibitor of the present invention, experimental technique, condition and the results are shown in Table 4.
Table 4
Numbering experimental technique material stopper begins polymerization time
(ppm) (hour)
1 material is through cooling knot MAA TMHPO50
Crystalline substance, 0.5 millimeter mercury 100% Me HQ50 45.0
Post vacuumized 15 fens
Clock, tube sealing, 90 ℃
Following polymerization
The true MAA TMHPO50 of 2 20 mmhg
Vacancy reason 20 minutes, 100% Me HQ50 48.0
Tube sealing is under 100 ℃
Polymerization
3 normal pressures, visual method, the same TMHPO50
100℃ Me HQ50 27.0
The same TMHPO100 15.5 of comparative example
The saturated 20 MAA TMHPO150 of 4 usefulness pure oxygens
Minute, 60% Me HQ150 16.5 on the liquid level
Portion protects with oxygen, IBA
100℃ 40%
The comparative example normal pressure, visual the same TMHPO150
Method, 100 ℃ of MeHQ150 35.0
Embodiment 5
With 900 gram MAA, 600 gram IBA pack in the there-necked flask, and flask central authorities adorn one long 1300 millimeters, fill 1 meter of stainless steel triangle wire filler in the concentric-tube column that internal diameter is 20 millimeters, post, and a total reflux condenser is adorned at the top.Overhead product directly returns in the there-necked flask, and material is circulated repeatedly, and the cat head end constantly drips stopper, and the tower still blasts micro-air.Under following condition, operate continuously 500 hours:
Still temperature: 90 ℃
Overbottom pressure: 20 mmhg
Reflux ratio: 5
Stopper: TMHPO and Me HQ each 50%, add-on is equivalent to the 0.025%(250ppm of dropping liq amount).
Blowing air amount: the 0.1%(volume of the quantity of steam that is equivalent to rise)
The result: no any polymerization sign in the tower, the viscosity of recycle stock, double bond content do not change.
Embodiment 6
Continuous rectification apparatus, 1300 millimeters of rectifying column lengths, 25 millimeters of internal diameters, in fill out 1000 millimeters of stainless steel triangle fillers, wherein rectifying section is 400 millimeters, 600 millimeters of stripping sections.Operate continuously is 500 hours under following condition;
Feed composition: MAA60%, IBA40%, stopper 100ppm(TMHPO and 4010NA each 50%)
Feeding temperature: 78 ℃
Feeding rate: 2 ml/min
Still temperature: 90 ℃
Top temperature: 67 ℃
Overbottom pressure: 14～20 mmhg
Reflux ratio: 5
Cat head drips the stopper amount: the 0.01%(100ppm that is equivalent to the dropping liq amount)
The result: operation is normal, and pressure reduction is stable in the tower, tears the no any polymerization sign of tower check open, and material viscosity, double bond content do not change.
Embodiment 7
Methacrylic acid, isopropylformic acid knockout tower, 0.1 meter of tower diameter, 13 meters of tower heights, 8 meters of interior dress ripple packings, operate continuously is 100 hours under following condition.
Feed composition: MAA60%, IBA40%, stopper 100ppm(TMHPO and Me HQ each 50%)
Inlet amount: 3.8 kilograms/hour
Feeding temperature: 77 ℃
Still temperature: 101 ℃
Top temperature: 73 ℃
Overbottom pressure: 20 mmhg
Stopper: splash into from the top, be equivalent to the 0.015%(150ppm of dropping liq amount)
Reflux ratio: 7
Tower still material is formed: more than the MAA96%
Overhead distillate is formed: MAA15%, IBA85%
The result: pressure reduction is stable in the tower, does not have any polymerization sign, and material viscosity does not change.
Claims (4)
1, a kind of composite polymerzation inhibitor that is used for methacrylic acid and ester class thereof is characterized in that it is to be formed by A component and any uniform mixing that is referred to as in the following compound of B component,
The A component is:
2,2,6,6-tetramethyl--4-hydroxy-piperdine nitroxyl free radical,
The B component is:
(1) N-sec.-propyl-N '-diphenyl-para-phenylene diamine,
(2) MEHQ,
(3) 2,2 '-methylene radical-two (4-methyl 6-tert.-butyl phenols),
(4) 4-tert-butyl catechol,
The weight ratio of A, B two components can be 0.1～10: change arbitrarily in 1 scope.
2, composite polymerzation inhibitor according to claim 1 is characterized in that the optimum weight ratio scope of A, B two components is 1～2: 1.
3, a kind of by A(2,2,6,6-tetramethyl--4-hydroxy-piperdine nitroxyl free radical) and B(N-sec.-propyl-N '-diphenyl-para-phenylene diamine, MEHQ, 2,2 '-two kinds of components of one of methylene radical-two (4-methyl 6-tert.-butyl phenols) or 4-tert-butyl catechol, and a kind of composition that combines with the weight ratio of A: B=0.1～10: 1, it is characterized in that said composition can be used for the stopper of methacrylic acid and ester class thereof, its amount ranges is 10～4800ppm, and its optimum range is 50～500ppm.
4, a kind of by A(2,2,6,6-tetramethyl--4-hydroxy-piperdine nitroxyl free radical) and B(N-sec.-propyl-N '-diphenyl-para-phenylene diamine, MEHQ, 2,2 '-two kinds of components of one of methylene radical-two (4-methyl 6-tert.-butyl phenols) or 4-tert-butyl catechol, and a kind of composition so that the weight ratio of A: B=0.1～10: 1 is combined into is characterized in that said composition can be used for methacrylic acid and separates with isobutyric underpressure distillation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN86103840A CN1010679B (en) | 1986-06-05 | 1986-06-05 | Compoundedinhibitor of polymerization for methacrylic acid and esters thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN86103840A CN1010679B (en) | 1986-06-05 | 1986-06-05 | Compoundedinhibitor of polymerization for methacrylic acid and esters thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN86103840A CN86103840A (en) | 1987-12-16 |
| CN1010679B true CN1010679B (en) | 1990-12-05 |
Family
ID=4802213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN86103840A Expired CN1010679B (en) | 1986-06-05 | 1986-06-05 | Compoundedinhibitor of polymerization for methacrylic acid and esters thereof |
Country Status (1)
| Country | Link |
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| CN (1) | CN1010679B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1065233C (en) * | 1994-06-02 | 2001-05-02 | 株式会社日本触媒 | Method for inhibiting polymerization of (meth) acrylic acid and esters thereof |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5728872A (en) * | 1994-06-27 | 1998-03-17 | Lutz Riemenschneider | Stabilized acrylic acid compositions |
| US6566467B1 (en) * | 1998-01-22 | 2003-05-20 | Donald Frederick Lyons | Inhibitor composition for chloroprene polymerization |
| US8691994B2 (en) | 2011-02-03 | 2014-04-08 | Nalco Company | Multi-component polymerization inhibitors for ethylenically unsaturated monomers |
| CN105693535B (en) * | 2016-02-26 | 2018-05-11 | 中国科学院长春应用化学研究所 | The preparation method of 3-N, N- dimethylamino ethyl acrylate |
| CN106397182A (en) * | 2016-08-31 | 2017-02-15 | 江苏三蝶化工有限公司 | Polymerization inhibitor for preparation apparatus of acrylic acid |
| CN115838322B (en) * | 2022-12-29 | 2024-03-29 | 杭州唯铂莱生物科技有限公司 | Polymerization inhibiting composition for olefin compounds and polymerization inhibiting method |
-
1986
- 1986-06-05 CN CN86103840A patent/CN1010679B/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1065233C (en) * | 1994-06-02 | 2001-05-02 | 株式会社日本触媒 | Method for inhibiting polymerization of (meth) acrylic acid and esters thereof |
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| Publication number | Publication date |
|---|---|
| CN86103840A (en) | 1987-12-16 |
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