CN105017560A - Waste recovery processing method for modified polyimide precursor composition film - Google Patents
Waste recovery processing method for modified polyimide precursor composition film Download PDFInfo
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- CN105017560A CN105017560A CN201510227525.3A CN201510227525A CN105017560A CN 105017560 A CN105017560 A CN 105017560A CN 201510227525 A CN201510227525 A CN 201510227525A CN 105017560 A CN105017560 A CN 105017560A
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- China
- Prior art keywords
- precursor composition
- polyimide precursor
- modified polyimide
- composition film
- film waste
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- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Abstract
The invention discloses a recovery processing method for a modified polyimide precursor composition film waste. The method comprises the following steps: smashing the modified polyimide precursor composition film waste into fragments of the modified polyimide composition film waste with the lengths of smaller than 5 mm, putting the fragments in stronger ammonia water for hydrolyzing, and performing centrifuging or filtering after the reaction is finished; acidizing hydrochloric acid for filter liquor obtained through separation, and then separating out crude pyromellitic acid; washing separated undissolved substances with hydrochloric acid or sulfuric acid, and performing secondary centrifuging or filtering to obtain a crude 4,4'-diaminodiphenyl ether water solution; and neutralizing the obtained crude 4,4'-diaminodiphenyl ether water solution with ammonia water until the pH value is equal to 8-10, and then separating out 4,44'-diaminodiphenyl ether. According to the method disclosed by the invention, the reaction rate is improved, the time is shortened, inorganic fillers in the modified polyimide film waste can be effectively removed, and the purity of a hydrolysis product is further improved.
Description
Technical field:
The invention belongs to chemical technology field, relate to the recovery complete processing of polyimide film waste, be specifically related to the recovery complete processing adopting nanometer inorganic filler modified polyimide precursor composition film waste.
Background technology
Polyimide refers to the base polymer containing imide ring (-CO-NH-CO-) on main chain, wherein important with the polymkeric substance containing imide structure.Polyimide, as the special engineered material of one, has been widely used in the fields such as Aeronautics and Astronautics, microelectronics, nanometer, liquid crystal, separatory membrane, laser.The sixties in last century, each state is all by the research of polyimide, development and utilization.Polyimide is put into one of 21 century most promising engineering plastics.Polyimide is because of its outstanding feature in performance and synthesis, no matter be as structured material or as functional material, its huge application prospect is familiar with fully, be known as " expert dealt with problems ", and think " not having polyimide would not have the microelectronics of today ".
Along with the fast development of microelectronic industry, the demand of this form of Kapton is also grown with each passing day, the quantity of the Kapton produced in polyimide production process and polyimide precursor composition film waste thereof is also increasing day by day, especially all benzene-type Thermocurable polyimide film.At present, main methods is burned and buries, not only contaminate environment, and waste resource.
Prior art JP2006-12450.2006.5.18 discloses: the polyimide products formed in pulverizing state or film, and the concentration with 0.05 ~ 20 % by weight drops in water, based on the imide mole number of polyimide, adds 20 ~ 80 times of hydroxide ion [OH
-] sodium hydroxide or potassium hydroxide, be hydrolyzed at ambient pressure in 40 ~ 95 DEG C.The advantage of this method need not High Temperature High Pressure, and low to the requirement of equipment, in the low molecule of recovery, impurity is less.This method is owing to adopting highly basic as hydrolytic reagent, and the alkalimetal ion remained in pyromellitic acid anhydride at high temperature can make its carbonization, and cause derived product with stain, visual appearance is poor, and product scrap rate improves.
In order to promote the performance of Kapton, manufacturer with the addition of various nanometer inorganic filler in polyimide film production process, as glass fibre (GF), carbon fiber (CF), molybdenumdisulphide (MoS2), silicon-dioxide (SiO2), titanium dioxide (TiO2), aluminum oxide (Al2O3), aluminium nitride (AlN), silicon nitride (SiN4), graphite (C) and carbon black (C) etc., blended technology is adopted to make polyimide film.Due to the introducing of various nanometer inorganic filler, also bring difficulty to recycling, in prior art, all do not point out how to be separated this part inorganic nano-filler.
Summary of the invention
The present invention is directed to the recycling complete processing that above defect provides polyimide film, achieve a series of modified polyimide precursor composition film wastes produced in polyimide film production process and reclaim the course of processing.
The object of the invention is to realize in the following manner:
A kind of modified polyimide precursor composition film waste reclaims working method, and the method comprises the following steps:
(1) modified polyimide precursor composition film waste removal of impurities, pulverizes, obtains the fragment that length is less than the modified polyimide precursor composition film waste of 5mm; Preferred length is 0.2 ~ 4mm;
(2) fragment is put in strong aqua, heated and stirred is hydrolyzed, and carries out centrifugal or filter after reaction terminates;
After the filtrate that separation obtains is equaled 2 ~ 6 by hcl acidifying to pH value, separate out thick Pyromellitic Acid; Preferable ph is 2;
After isolated insolubles hydrochloric acid or sulfuric acid scrubbing to pH value are equaled 2 ~ 6, carry out second time centrifugal or filter, obtain thick 4, the 4'-diaminodiphenyl oxide aqueous solution; Preferable ph is 6;
(3) after thick 4, the 4'-diaminodiphenyl oxide aqueous solution ammonia neutralizations obtained equal 8 ~ 10 to pH value, separate out 4, diaminodiphenyl oxide, dry.Preferable ph is 8.
By thick Pyromellitic Acid deionized water wash in step (2), dry, sublimation purification, obtains electronic-grade pyromellitic acid anhydride.
Strong aqua concentration described in step (2) is 22 ~ 24wt%.In preferred steps (2), hydrolysising condition is temperature 150 ~ 190 DEG C, and pressure 2 ~ 5MPa, hydrolysis time is 90 ~ 120min.Polyimide film solid content is 25wt%, most preferably at 150 DEG C, is hydrolyzed 120min under 2MPa, and polyimide film waste material complete hydrolysis can become dianhydride and diamines completely.Modified polyimide precursor composition film solid content is 30wt%, and most preferably at 150 DEG C, heating hydrolysis 90min under 2MPa, polyimide precursor composition film waste complete hydrolysis can become dianhydride and diamines completely.
In step (2), acidified filtrate working concentration is the hydrochloric acid of 20 ~ 35wt%; The washing hydrochloric acid of insolubles with 20 ~ 35wt% or the sulfuric acid of 35wt%.
Ammonia concn described in step (3) is 22 ~ 24wt%.
4, the 4'-diaminodiphenyl oxides that step (3) obtains are again through distilling or obtaining electronic-grade 4,4'-diaminodiphenyl oxide with ethyl alcohol recrystallization.
The temperature of drying in step (3) is 60 DEG C ~ 80 DEG C, is preferably 70 DEG C.
Polyimide precursor composition film refers to and is dissolved in containing dianhydride and diamines the glue configured in organic solvent, deviates from through curtain coating the film formed after partial solvent.
Polyimide film refers to the Kapton adding performance boost after nanometer inorganic filler.Polyimide film is by preparation process, add nanometer inorganic filler, adopt conventional blending technology to make the polyimide film of different performance, the characteristic such as electrical property (as specific inductivity), mechanical property (as modulus, intensity and elongation at break), dimensional stability mainly for polyimide carries out modification.Main nanometer inorganic filler has: glass fibre (GF), carbon fiber (CF), molybdenumdisulphide (MoS
2), silicon-dioxide (SiO
2), titanium dioxide (TiO
2), aluminum oxide (Al2O
3), aluminium nitride (AlN), silicon nitride (SiN
4), graphite (C) or carbon black (C) etc.
It is as follows that above-mentioned modified polyimide precursor composition film reclaims the preferred concrete steps of complete processing: modified polyimide precursor composition film waste clear water washing by soaking removes the impurity on surface, then pulverize with high speed rotating multistage grinder, obtain the fragment (length is less than 5mm) of polyimide film and polyimide precursor composition thereof, the fragment of gained is put in be equipped with in the special reaction vessel of strong aqua, heating, stirring.Modified polyimide precursor composition film waste complete hydrolysis obtains the mixture of Pyromellitic Acid, 4,4'-diaminodiphenyl oxides and mineral filler, and wherein insolubles is thick 4,4'-diaminodiphenyl oxides and mineral filler, and solution is the aqueous solution of Pyromellitic Acid.Through first time centrifugal or first time filtering separation, after insolubles 35wt% hydrochloric acid or sulfuric acid scrubbing to pH value equal 6, carry out second time centrifugal or second time filter removal mineral filler, obtain the aqueous solution of thick 4,4'-diaminodiphenyl oxides.After 8 are equaled with ammonia neutralization to the pH value of 22 ~ 24wt% to this aqueous solution, separate out 4,4'-diaminodiphenyl oxide, in vacuum drying oven, 70 DEG C of oven dry, then through distilling or obtaining electronic-grade 4,4'-diaminodiphenyl oxide with ethyl alcohol recrystallization.After filtrate after being filtered first time equals 2 by 35wt% hcl acidifying to pH value, separate out thick Pyromellitic Acid.With deionized water wash, dry, sublimation purification, obtains electronic-grade pyromellitic acid anhydride.
The technology used in the present invention principle is: the strong aqua of employing is the hydrate of ammonia and water, and chemical formula is NH
3h
2o, can be dissociated into NH4 in water
+and OH
-.Wherein NH4
+nH can be dissociated into further in water
3h
2o and H
+.
OH
-acting in polyimide is C-N key, makes it rupture, OH
-be coordinated on C atom, form carboxyl, H
+be coordinated in atom N, formed amino.Thus modified polyimide and polyimide precursor composition thereof are hydrolyzed into Pyromellitic Acid, 4,4'-diaminodiphenyl oxides and mineral filler.
Pyromellitic acid anhydride is produced in Pyromellitic Acid dehydration, and concrete reaction formula is as follows:
Compared to the prior art the beneficial effect that has of institute the present invention: the present invention, by being fully crushed to certain length to modified polyimide precursor composition film waste, improve the contact area of reaction, increases speed of reaction, shorten the time.Traditional technology needs more than 16 hours, and present the present invention can control within 2 hours.Invention increases the separation of mineral filler and 4,4'-diaminodiphenyl oxide, pyromellitic acid anhydride simultaneously, effectively can remove mineral filler in modified polyimide precursor composition film waste, improve the purity of hydrolysis prods further.
Embodiment
Below by way of specific embodiment, the present invention is further described:
Embodiment 1
(1) glass fibre (GF) suspension liquid preparation
Adopt nano-grade glass fibre (GF) 12.5g, add in 2000ml non-protonic solvent N,N-dimethylacetamide (DMAc), under 20kHz ultrasonic wave dispersion condition, fully stir 60min, make stable suspension liquid.
(2) preparation of modified polyamide acid composite solution
The suspension liquid of above-mentioned acquisition is added in polyamic acid polymerization reaction kettle, control temperature is at 10-60 DEG C, add 4 of 239.3g, 4 '-diaminodiphenyl oxide, carry out mechanical stirring, after it dissolves completely, temperature is between 50 ~ 60 DEG C, add pyromellitic acid anhydride 260.7g in batches while stirring, make the polyamic acid composite solution of uniform viscosity stablization.
(3) the making of modified polyimide precursor composition film
Polyamic acid composite solution obtained above is formed liquid film on clean steel plate, is put in baking oven, temperature controls 150 ~ 200 DEG C, and the time, at 10 ~ 15 minutes, deviates from partial solvent, obtains polyimide precursor composition film.
(4) the recovery processing of modified polyimide precursor polymer film waste
Modified polyimide precursor composition film waste 150g removal of impurities being ground into 0.2mm length joins in 3000ml stainless steel vessel, and the ammoniacal liquor that concentration is 22wt% has been housed in container.Temperature 150 DEG C, hydrolysis reaction 90min under pressure 2MPa, cooling, filtration, filter insolubles 4, the 4'-diaminodiphenyl oxide and mineral filler solid that obtain, equal 64 with 35wt% hydrochloric acid or sulfuric acid scrubbing to pH value, soluble in water after 4'-diaminodiphenyl oxide solid and acid-respons, mineral filler is water insoluble, carries out secondary centrifuging or secondary filtration removal mineral filler, obtains the aqueous solution of thick diamines.After 8 are equaled to ammonia neutralization to the pH value of the aqueous solution 22wt% of the thick diamines of gained, separate out diamines, in vacuum drying oven, dry at 70 DEG C.Again through distilling or obtaining 4,4'-diaminodiphenyl oxide with ethyl alcohol recrystallization.Product purity is 99.9%, fusing point 191 ~ 192 DEG C.65.9g (theoretical 70.0g must be measured) must be measured.
By once filter after filtrate equal 2 by 35wt% hydrochloric acid or sulfuric acid acidation to pH value after, separate out thick Pyromellitic Acid.With deionized water wash, dry, sublimation purification, obtains pyromellitic acid anhydride.Product purity is 99.5%, fusing point 284 ~ 285 DEG C.71.2g (theoretical 76.25g must be measured) must be measured.
Embodiment 2
Glass fibre (GF) in example 1 is changed into silicon-dioxide, and 4,4'-diaminodiphenyl oxide must be measured as 64.1g, and product purity is 99.9%, fusing point 191 ~ 192 DEG C.Pyromellitic acid anhydride product must measure 69.3g.Product purity is 99.5%, fusing point 284 ~ 285 DEG C.Except above variation, other operation stepss and quality product consistent with embodiment 1.
Embodiment 3
Glass fibre (GF) in example 1 is changed into aluminum oxide (Al
2o
3), 4,4'-diaminodiphenyl oxide must be measured as 64.2g.Product purity is 99.9%, fusing point 191 ~ 192 DEG C.Pyromellitic acid anhydride product must measure 69.1g.Product purity is 99.5%, fusing point 284 ~ 285 DEG C.Except above variation, other operation stepss and quality product consistent with embodiment 1.
Embodiment 4
Glass fibre (GF) in example 1 is changed into silicon nitride (SiN
4), 4,4'-diaminodiphenyl oxide must be measured as 64.5g.Product purity is 99.9%, fusing point 191 ~ 192 DEG C.Pyromellitic acid anhydride product must measure 69.8g.Product purity is 99.5%, fusing point 284 ~ 285 DEG C.Except above variation, other operation stepss and quality product consistent with embodiment 1.
Embodiment 5
Glass fibre (GF) in example 1 is changed into carbon black (C), and 4,4'-diaminodiphenyl oxide must be measured as 63.3g.Product purity is 99.9%, fusing point 191 ~ 192 DEG C.Pyromellitic acid anhydride product must measure 68.9g.Product purity is 99.5%, fusing point 284 ~ 285 DEG C.Except above variation, other operation stepss and quality product consistent with embodiment 1.
Embodiment 6
The length that modified polyimide precursor composition film waste in embodiment 1 is pulverized is changed into 4mm, hydrolysis reaction 120min.4,4'-diaminodiphenyl oxide purity is 99.0%, fusing point 191 ~ 193 DEG C.63.6g must be measured.Pyromellitic acid anhydride product purity is 99.0%, fusing point 284 ~ 285 DEG C.69.5g must be measured.Except above variation, other operation stepss are consistent with embodiment 1.
Embodiment 7
The length that modified polyimide precursor composition film waste in embodiment 1 is pulverized is changed into 0.2mm, by cooling, filter, hydrolysate solid-liquid separation, filtration obtains 4,4'-diaminodiphenyl oxide and nanometer inorganic filler solid, is separated no longer further, direct ethyl alcohol recrystallization obtains 4,4'-diaminodiphenyl oxide, product purity is 95.0%, fusing point 191 ~ 195 DEG C.Must 68.1g be measured, except above variation, other operation stepss and quality product consistent with embodiment 1.
Claims (10)
1. modified polyimide precursor composition film waste reclaims a working method, it is characterized in that the method comprises the following steps:
(1) modified polyimide precursor composition film waste removal of impurities, pulverizes, obtains the fragment that length is less than the modified polyimide precursor composition film waste of 5mm;
(2) fragment is put in strong aqua, heated and stirred is hydrolyzed, and carries out centrifugal or filter after reaction terminates; After the filtrate that separation obtains is equaled 2 ~ 6 by hcl acidifying to pH value, separate out thick Pyromellitic Acid;
After isolated insolubles hydrochloric acid or sulfuric acid scrubbing to pH value are equaled 2 ~ 6, carry out second time centrifugal or filter, obtain thick 4, the 4'-diaminodiphenyl oxide aqueous solution;
(3) after thick 4, the 4'-diaminodiphenyl oxide aqueous solution ammonia neutralizations obtained equal 8 ~ 10 to pH value, separate out 4,4'-diaminodiphenyl oxide, dry.
2. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that step (3) obtains 4,4'-diaminodiphenyl oxide is again through distilling or obtaining electronic-grade 4,4'-diaminodiphenyl oxide with ethyl alcohol recrystallization.
3. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that the temperature of drying in step (3) is 60 DEG C ~ 80 DEG C.
4. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that thick Pyromellitic Acid deionized water wash in step (2), dry, sublimation purification, obtains electronic-grade pyromellitic acid anhydride.
5. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that the strong aqua concentration described in step (2) is 22 ~ 24wt%.
6. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that in step (2), hydrolysising condition is temperature 150 ~ 190 DEG C, pressure 2 ~ 5MPa.
7. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that in step (2), hydrolysis time is 90 ~ 120min.
8. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that in step (2), acidified filtrate working concentration is the hydrochloric acid of 20 ~ 35wt%; The washing hydrochloric acid of insolubles with 20 ~ 35wt% or the sulfuric acid of 20 ~ 35wt%.
9. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that the ammonia concn described in step (3) is 22 ~ 24wt%.
10. modified polyimide precursor composition film waste according to claim 1 reclaims working method, it is characterized in that described modified polyimide precursor composition film refers to and be dissolved in containing dianhydride and diamines the glue configured in organic solvent, deviate from through curtain coating the film formed after partial solvent, the nanometer inorganic filler that modification uses has: glass fibre, carbon fiber, molybdenumdisulphide, silicon-dioxide, titanium dioxide, aluminum oxide, aluminium nitride, silicon nitride, graphite or carbon black.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113354527A (en) * | 2021-06-17 | 2021-09-07 | 中国科学院山西煤炭化学研究所 | Method for degrading polyimide material by microwave |
| CN113372212A (en) * | 2021-06-17 | 2021-09-10 | 中国科学院山西煤炭化学研究所 | Method for recovering polyimide by selectively breaking imide bonds |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1045800A (en) * | 1990-04-13 | 1990-10-03 | 天津市绝缘材料总厂 | The recovery method of polyimide film waste |
| CN1324789A (en) * | 2001-06-26 | 2001-12-05 | 中国科学院长春应用化学研究所 | Polyimide hydrolyzing recovery process |
| CN103553906A (en) * | 2013-11-05 | 2014-02-05 | 上海固创化工新材料有限公司 | Method of recovering polyimide raw material by hydrolyzing polyimide waste thin film by ammonia water |
-
2015
- 2015-05-06 CN CN201510227525.3A patent/CN105017560A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1045800A (en) * | 1990-04-13 | 1990-10-03 | 天津市绝缘材料总厂 | The recovery method of polyimide film waste |
| CN1324789A (en) * | 2001-06-26 | 2001-12-05 | 中国科学院长春应用化学研究所 | Polyimide hydrolyzing recovery process |
| CN103553906A (en) * | 2013-11-05 | 2014-02-05 | 上海固创化工新材料有限公司 | Method of recovering polyimide raw material by hydrolyzing polyimide waste thin film by ammonia water |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113354527A (en) * | 2021-06-17 | 2021-09-07 | 中国科学院山西煤炭化学研究所 | Method for degrading polyimide material by microwave |
| CN113372212A (en) * | 2021-06-17 | 2021-09-10 | 中国科学院山西煤炭化学研究所 | Method for recovering polyimide by selectively breaking imide bonds |
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Application publication date: 20151104 |