CN103592412A - Hydroxyl value detection method - Google Patents
Hydroxyl value detection method Download PDFInfo
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- CN103592412A CN103592412A CN201310532558.XA CN201310532558A CN103592412A CN 103592412 A CN103592412 A CN 103592412A CN 201310532558 A CN201310532558 A CN 201310532558A CN 103592412 A CN103592412 A CN 103592412A
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- hydroxyl value
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- detection method
- sample
- reaction
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- 125000002887 hydroxy group Chemical group [H]O* 0.000 title claims abstract description 32
- 238000001514 detection method Methods 0.000 title claims abstract description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000006243 chemical reaction Methods 0.000 claims abstract description 13
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000006460 hydrolysis reaction Methods 0.000 claims abstract description 10
- KJFMBFZCATUALV-UHFFFAOYSA-N phenolphthalein Chemical compound C1=CC(O)=CC=C1C1(C=2C=CC(O)=CC=2)C2=CC=CC=C2C(=O)O1 KJFMBFZCATUALV-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000012153 distilled water Substances 0.000 claims abstract description 6
- 238000007789 sealing Methods 0.000 claims abstract description 6
- 238000001816 cooling Methods 0.000 claims abstract description 5
- 150000007529 inorganic bases Chemical class 0.000 claims abstract description 5
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 25
- 239000003513 alkali Substances 0.000 claims description 12
- 238000004448 titration Methods 0.000 claims description 11
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 238000012360 testing method Methods 0.000 claims description 8
- JUJWROOIHBZHMG-UHFFFAOYSA-N pyridine Substances C1=CC=NC=C1 JUJWROOIHBZHMG-UHFFFAOYSA-N 0.000 claims description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 6
- 230000007062 hydrolysis Effects 0.000 claims description 5
- 239000002253 acid Substances 0.000 claims description 4
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 claims description 4
- 241001411320 Eriogonum inflatum Species 0.000 claims description 3
- 230000035484 reaction time Effects 0.000 claims description 3
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical class CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 claims description 2
- 150000002894 organic compounds Chemical class 0.000 abstract description 3
- 238000004458 analytical method Methods 0.000 abstract description 2
- 239000000126 substance Substances 0.000 abstract description 2
- LEYDCYBWBLIGTC-UHFFFAOYSA-N acetyl acetate 1H-imidazole pyridine Chemical compound N1=CC=CC=C1.N1C=NC=C1.C(C)(=O)OC(C)=O LEYDCYBWBLIGTC-UHFFFAOYSA-N 0.000 abstract 1
- 230000001476 alcoholic effect Effects 0.000 abstract 1
- 238000005303 weighing Methods 0.000 abstract 1
- WFDIJRYMOXRFFG-UHFFFAOYSA-N Acetic anhydride Chemical compound CC(=O)OC(C)=O WFDIJRYMOXRFFG-UHFFFAOYSA-N 0.000 description 19
- 238000005917 acylation reaction Methods 0.000 description 7
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 5
- LCZVSXRMYJUNFX-UHFFFAOYSA-N 2-[2-(2-hydroxypropoxy)propoxy]propan-1-ol Chemical compound CC(O)COC(C)COC(C)CO LCZVSXRMYJUNFX-UHFFFAOYSA-N 0.000 description 4
- 150000008065 acid anhydrides Chemical class 0.000 description 4
- 238000006136 alcoholysis reaction Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 2
- LGRFSURHDFAFJT-UHFFFAOYSA-N Phthalic anhydride Natural products C1=CC=C2C(=O)OC(=O)C2=C1 LGRFSURHDFAFJT-UHFFFAOYSA-N 0.000 description 2
- JHIWVOJDXOSYLW-UHFFFAOYSA-N butyl 2,2-difluorocyclopropane-1-carboxylate Chemical compound CCCCOC(=O)C1CC1(F)F JHIWVOJDXOSYLW-UHFFFAOYSA-N 0.000 description 2
- 150000002460 imidazoles Chemical class 0.000 description 2
- DXTCRSXRMZSEQP-UHFFFAOYSA-N 2-benzofuran-1,3-dione;pyridine Chemical compound C1=CC=NC=C1.C1=CC=C2C(=O)OC(=O)C2=C1 DXTCRSXRMZSEQP-UHFFFAOYSA-N 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- BLAKAEFIFWAFGH-UHFFFAOYSA-N acetyl acetate;pyridine Chemical compound C1=CC=NC=C1.CC(=O)OC(C)=O BLAKAEFIFWAFGH-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- -1 hydroxy ester Chemical class 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229920005906 polyester polyol Polymers 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- UMJSCPRVCHMLSP-UHFFFAOYSA-N pyridine Natural products COC1=CC=CN=C1 UMJSCPRVCHMLSP-UHFFFAOYSA-N 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
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- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The invention relates to a chemical detection method, particularly to a method for detecting the hydroxyl value of a high molecular weight organic compound containing active hydroxyl. The hydroxyl value detection method includes the steps of: weighing sample in a container, and taking another empty container; pipetting an acetic anhydride-imidazole-pyridine solution into the sample loaded container and the empty container respectively, shaking the solution well, sealing the containers and placing them in a water bath to undergo reaction under certain temperature; at the end of the reaction, pulling out corks, adding distilled water quickly, then sealing bottlenecks, and placing the containers in a water tank to undergo hydrolysis reaction; at the end of the hydrolysis reaction, taking the two containers out of the water bath, and performing cooling; adding several drops of a phenolphthalein indicator dropwise into the two containers respectively after cooling to room temperature; titrating the container solutions to pink respectively by an alcoholic solution of inorganic base, and calculating the hydroxyl value of the sample according to a formula. The method provided by the invention has the advantages of simple analysis steps, high precision, and good accuracy.
Description
Technical field
The present invention relates to a kind of chemical detection method, particularly a kind of hydroxyl value detection method of the high molecular organic compound containing activity hydroxy.
Background technology
The hydroxyl value of common industrial use refers to the milligram number of the potassium hydroxide (KOH) that the hydroxyl in hydroxyl value (Hydroxyl value) 1g sample is suitable, with mgKOH/g, represents.The hydroxyl value detection method of present adopts phthalic anhydride-pyridine method or acetic anhydride-pyridine method more, the principle detecting is first to allow excessive and quantitative acid anhydrides and the hydroxyl reaction of determinand, use again the unnecessary acid anhydrides of KOH solution titration, then with formula, calculate the hydroxyl value of determinand.
The shortcoming of existing detection method has: 1. acylation reaction temperature Tai Gaoyi causes personal safety or mishap; 2. incomplete by the words acylation reaction of phthalic anhydride; 3. in the words acylation reaction process with acetic anhydride, have the volatilization of acetic anhydride, cause result inaccurate; 4. in the process of titration, under normal temperature, acid anhydrides is slower with the reaction of water, and titration end-point is indefinite.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of polyether glycol, polyester polyol, crylic acid hydroxy ester etc. containing the detection method of the hydroxyl value of the high molecular organic compound of activity hydroxy.
Technical matters to be solved by this invention is achieved by the following technical programs:
A detection method, the method comprises the following steps:
1) take sample in container, and separately get an electrical condenser;
2) to being equipped with in the container of sample and electrical condenser, pipette acetic anhydride-imidazoles-pyridine solution respectively, after shaking up, its sealing is placed in to water bath, react at a certain temperature;
3) reaction is opened bottle stopper after finishing and is added rapidly distilled water bottleneck to be shut to be placed in the tank reaction that is hydrolyzed again;
4) treat that hydrolysis reaction finishes, two containers are taken out from water bath, carry out cooling;
5) in two containers, splash into several phenolphthalein indicators respectively after being cooled to room temperature;
6) the inorganic alkali alcosol that is c by concentration is respectively titrated to pink by container solution, and the volume that sample receiver and blank container consume inorganic alkali alcosol is respectively V
mand V
0, and calculate as follows hydroxyl value testing result:
Hydroxyl value=[(V
0-V
m) * c * M]/W+A.V
In formula: V
m=sample consumes the volume of inorganic alkali alcosol, mL;
V
0=blank the volume that consumes inorganic alkali alcosol, mL;
The concentration of the inorganic alkali alcosol of c=, mol/L;
The molecular weight of M=inorganic base;
W=takes the quality of sample, g;
The acid number of A.V=sample, mgKOH/g.
Further, the temperature of reaction in described step 2 is 88 ~ 93 ℃, and the reaction time is 0.75 ~ 1.5 hour.
Further, the hydrolysis temperature in described step 3 is 88 ~ 93 ℃, and hydrolysis time is 5 ~ 10 minutes.
Further, the inorganic base in described step 6 is at least one in NaOH, potassium hydroxide.
Further, the alcohol in described step 6 is at least one in methyl alcohol, ethanol, propyl alcohol, butanols.
Further, in described step 6, use inorganic alkali alcosol that container solution is titrated to pink, within 15 seconds, solution is colour-fast, is titration end-point, otherwise continues to be titrated to solution pinkiness.
In the present invention, inventor adopts acetic anhydride-imidazoles-pyridine solution as acylating reagent, and the imidazoles adding can play the effect of catalysis, acidylates temperature and just can carry out completely 90 ℃ of left and right.And sealing can effectively prevent the volatilization of acetic acid and acetic anhydride, greatly reduce the error of test.And after acylation reaction finishes, add distilled water to follow the reaction that is hydrolyzed of remaining acetic anhydride to generate acetic acid and can reduce system test error.
The present invention has following beneficial effect:
Alcoholysis reaction temperature of the present invention is low, is difficult for causing personal safety or mishap; The acylation reaction of acid anhydrides is complete, and measurement result is more accurate; Acylation reaction process there will not be sour loss and while avoiding detecting error titration, and titration end-point is easily judgement and not having repeatedly obviously.
Embodiment
Below in conjunction with embodiment, the present invention will be described in detail, and embodiment is only the preferred embodiment of the present invention, is not limitation of the invention.
The present embodiment is with tripropylene glycol common on market as detected object, and the theoretical hydroxyl value scope of its sample is between 580-600.
Acetic anhydride-imidazoles-pyridine solution is dissolved in 500mL pyridine by 50g acetic anhydride, then adds 12g imidazoles, after stirring, is placed in brown bottle.
The present embodiment carries out respectively 5 hydroxyl value analyses according to following steps:
1) take tripropylene glycol W in the container of 250mL, and separately get an electrical condenser;
2) to being equipped with in the container of sample and electrical condenser, pipette 20mL acetic anhydride-imidazoles-pyridine solution respectively, after shaking up, its sealing is placed in to the acylation reaction that the water bath of 90 ℃ carries out 1 hour;
3) reaction open after finishing bottle stopper add rapidly 1mL distilled water more just bottleneck shut and be placed in the tank reaction that is hydrolyzed, the reaction time is 5 minutes;
4) treat that hydrolysis reaction finishes, two containers are taken out from water bath, carry out cooling;
5) in two containers, splash into several phenolphthalein indicators respectively after being cooled to room temperature;
6) ethanolic solution of the potassium hydroxide that is 0.5mol/L by concentration is respectively titrated to pink by container solution, and the volume that sample receiver and blank container consume the ethanolic solution of potassium hydroxide is respectively V
mand V
0, and calculate as follows hydroxyl value testing result:
Hydroxyl value=[(V
0-V
m) * c * 56.1]/W+A.V
In formula: V
m=sample consumes the volume of the ethanolic solution of potassium hydroxide, mL
V
0=blank the volume that consumes the ethanolic solution of potassium hydroxide, mL
The concentration of the ethanolic solution of c=potassium hydroxide, mol/L;
W=takes the quality of sample, g;
The acid number of A.V=sample, mgKOH/g.
Test result is as shown in the table:
Adopt general detection method to detect data as follows:
By upper table, can obviously be seen, via general method when detecting tripropylene glycol (TPG) hydroxyl value because alcoholysis reaction does not thoroughly cause, testing result is mutually far short of what is expected with theoretical value, and in titration process, because the speed of phthalic anhydride alcoholysis is slower, cause when titration, through terminal, be difficult for judgement.And while adopting this method to detect, owing to having used distilled water to carry out hydrolysis process to the acetic anhydride of not alcoholysis before titration, make titration end-point more clear, and easily judgement, testing result is also more close to theoretical value.
The above embodiment has only expressed embodiments of the present invention; it describes comparatively concrete and detailed; but can not therefore be interpreted as the restriction to the scope of the claims of the present invention; as long as employing is equal to the technical scheme that the form of replacement or equivalent transformation obtains, within all should dropping on protection scope of the present invention.
Claims (6)
1. a hydroxyl value detection method, is characterized in that the method comprises the following steps:
1) take sample in container, and separately get an electrical condenser;
2) to being equipped with in the container of sample and electrical condenser, pipette acetic anhydride-imidazoles-pyridine solution respectively, after shaking up, its sealing is placed in to water bath, react at a certain temperature;
3) reaction is opened bottle stopper after finishing and is added rapidly distilled water bottleneck to be shut to be placed in the tank reaction that is hydrolyzed again;
4) treat that hydrolysis reaction finishes, two containers are taken out from water bath, carry out cooling;
5) in two containers, splash into several phenolphthalein indicators respectively after being cooled to room temperature;
6) the inorganic alkali alcosol that is c by concentration is respectively titrated to pink by container solution, and the volume that sample receiver and blank container consume inorganic alkali alcosol is respectively V
mand V
0, and calculate as follows hydroxyl value testing result:
Hydroxyl value=[(V
0-V
m) * c * M]/W+A.V
In formula: V
m=sample consumes the volume of inorganic alkali alcosol, mL;
V
0=blank the volume that consumes inorganic alkali alcosol, mL;
The concentration of the inorganic alkali alcosol of c=, mol/L;
The molecular weight of M=inorganic base;
W=takes the quality of sample, g;
The acid number of A.V=sample, mgKOH/g.
2. a kind of hydroxyl value detection method according to claim 1, is characterized in that: the temperature of reaction in described step 2 is 88 ~ 93 ℃, and the reaction time is 0.75 ~ 1.5 hour.
3. a kind of hydroxyl value detection method according to claim 1, is characterized in that: the hydrolysis temperature in described step 3 is 88 ~ 93 ℃, and hydrolysis time is 5 ~ 10 minutes.
4. a kind of hydroxyl value detection method according to claim 1, is characterized in that: the inorganic base in described step 6 is at least one in NaOH, potassium hydroxide.
5. a kind of hydroxyl value detection method according to claim 1, is characterized in that: the alcohol in described step 6 is at least one in methyl alcohol, ethanol, propyl alcohol, butanols.
6. a kind of hydroxyl value detection method according to claim 1, it is characterized in that: in described step 6, use inorganic alkali alcosol that container solution is titrated to pink, within 15 seconds, solution is colour-fast, be titration end-point, otherwise continue to be titrated to solution pinkiness.
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| CN201310532558.XA CN103592412A (en) | 2013-11-01 | 2013-11-01 | Hydroxyl value detection method |
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|---|---|---|---|
| CN201310532558.XA CN103592412A (en) | 2013-11-01 | 2013-11-01 | Hydroxyl value detection method |
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Family
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Cited By (8)
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| CN104020251A (en) * | 2014-06-20 | 2014-09-03 | 泸州北方化学工业有限公司 | Method for determining alcohol hydroxyl value |
| CN104950071A (en) * | 2014-03-27 | 2015-09-30 | 上海宝钢化工有限公司 | Method for measuring coumarone hydroxyl value |
| CN106442502A (en) * | 2016-09-29 | 2017-02-22 | 扬州晨化新材料股份有限公司 | Determination method for molecular weight of polyether amine |
| CN106770924A (en) * | 2017-03-23 | 2017-05-31 | 西南铝业（集团）有限责任公司 | A kind of assay method of ROLLING OIL and its additive middle hydroxyl value content |
| CN107389673A (en) * | 2017-07-24 | 2017-11-24 | 北京泛博科技有限责任公司 | A kind of assay method of organic matter hydroxyl value and application |
| CN110988255A (en) * | 2019-12-23 | 2020-04-10 | 嘉兴禾大科技有限公司 | Method for measuring hydroxyl value of hydroxyl-terminated organosilicon |
| CN111458453A (en) * | 2020-05-12 | 2020-07-28 | 万华化学集团股份有限公司 | Method for testing hydroxyl value in lactide-containing polylactic acid and application thereof |
| CN112285273A (en) * | 2020-11-16 | 2021-01-29 | 黄河三角洲京博化工研究院有限公司 | Method for detecting hydroxyl value content of dimethylolpropionic acid |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104950071A (en) * | 2014-03-27 | 2015-09-30 | 上海宝钢化工有限公司 | Method for measuring coumarone hydroxyl value |
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| CN106442502A (en) * | 2016-09-29 | 2017-02-22 | 扬州晨化新材料股份有限公司 | Determination method for molecular weight of polyether amine |
| CN106770924A (en) * | 2017-03-23 | 2017-05-31 | 西南铝业（集团）有限责任公司 | A kind of assay method of ROLLING OIL and its additive middle hydroxyl value content |
| CN106770924B (en) * | 2017-03-23 | 2019-04-02 | 西南铝业（集团）有限责任公司 | A kind of measuring method of ROLLING OIL and its additive middle hydroxyl value content |
| CN107389673A (en) * | 2017-07-24 | 2017-11-24 | 北京泛博科技有限责任公司 | A kind of assay method of organic matter hydroxyl value and application |
| CN110988255A (en) * | 2019-12-23 | 2020-04-10 | 嘉兴禾大科技有限公司 | Method for measuring hydroxyl value of hydroxyl-terminated organosilicon |
| CN111458453A (en) * | 2020-05-12 | 2020-07-28 | 万华化学集团股份有限公司 | Method for testing hydroxyl value in lactide-containing polylactic acid and application thereof |
| CN111458453B (en) * | 2020-05-12 | 2022-07-12 | 万华化学(四川)有限公司 | Method for testing hydroxyl value in lactide-containing polylactic acid and application thereof |
| CN112285273A (en) * | 2020-11-16 | 2021-01-29 | 黄河三角洲京博化工研究院有限公司 | Method for detecting hydroxyl value content of dimethylolpropionic acid |
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Application publication date: 20140219 |