CN106198772B - The method for measuring low free toluene diisocyanate content in base polyurethane prepolymer for use as - Google Patents
The method for measuring low free toluene diisocyanate content in base polyurethane prepolymer for use as Download PDFInfo
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- CN106198772B CN106198772B CN201610424674.3A CN201610424674A CN106198772B CN 106198772 B CN106198772 B CN 106198772B CN 201610424674 A CN201610424674 A CN 201610424674A CN 106198772 B CN106198772 B CN 106198772B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N30/04—Preparation or injection of sample to be analysed
- G01N30/06—Preparation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N30/00—Investigating or analysing materials by separation into components using adsorption, absorption or similar phenomena or using ion-exchange, e.g. chromatography or field flow fractionation
- G01N30/02—Column chromatography
- G01N2030/022—Column chromatography characterised by the kind of separation mechanism
- G01N2030/027—Liquid chromatography
Abstract
The method of low free toluene diisocyanate content is using high performance liquid chromatograph in a kind of measurement base polyurethane prepolymer for use as, and Detection wavelength is 220nm to 237nm, and the mode of gradient elution, directly dissolution measure, peak area quantified by external standard method.The present invention has easy to operate, high sensitivity, and separating degree is good, and detection range is wide, the free TDI of energy Accurate Determining low concentration.
Description
Technical field
The invention belongs to it is a kind of measure toluene diisocyanate content method, and in particular to a kind of high performance liquid chromatography
The method that method measures low free toluene diisocyanate (TDI) content in base polyurethane prepolymer for use as.
Technical background
There are unreacted toluene di-isocyanate(TDI) (i.e. free TDI) in TDI system polyurethane prepolymer, there is strong thorn
Swash smell, is done harm to huamn body after human body sucking.In the world today under the increasingly stringent situation of environmental requirement, in performed polymer
Free monomer content must control below 0.5%, some has reached 0.1% or less, this allows for micro or even microscratch amount
Analysis detection TDI content necessitates.
Currently, there are three types of the detection methods of free TDI content: chemical method, gas-chromatography spectrometry, high performance liquid chromatography,
But all there are some problems in every kind of method.
Chemical method (1.Free Toluene Diisocyanatein Urelymers, ASTM method D2615-70,
American Society fo Testing and Materials, Phidelphia pa, 1974.) be with n-hexane extraction,
Dibutyl amine titration, this method process is simple, but is not easy Accurate Determining.
When gas chromatography and the content of Gas Chromatography-Mass Spectrometry free TDI, (2.N.R.Neubauer,
G.R.Skreckoski, R.G.White and A.J.Kane, Anal.Chem.35 1647.) due to the heating of TDI prepolymer it is easy
It decomposes, when injector temperature is high, prepolymer, which decomposes, generates TDI, influences testing result；When the room temperature that gasifies is low, TDI cannot be complete
Full gasification.So there are serious problems for accuracy and precision.
High performance liquid chromatography includes two kinds, one is with methanol it is derivative after with reverse phase C18 column (3.K.Marcali,
Anal.Chem., 29 552.), and first alcohol and water does mobile phase, UV detector detection.This method will derive, more troublesome,
And pilot process can introduce error；Another kind is using (4.Von Uwe Lotz fared+lack
Heft.Quantitative Bestimmung monomerer Isocyanate85:172-75) high performance liquid chromatography positive silicon
Rubber column gel column directly detects, but all has that separating degree is not high, and detection sensitivity is low, the problem of low concentration detection inaccuracy.
Summary of the invention
The object of the present invention is to provide one kind directly, quick, easy, measurement range is wide, and high sensitivity, accuracy are high, heavy
The method of low-free TDI content in the good high performance liquid chromatography measurement base polyurethane prepolymer for use as of renaturation.
Method of the invention comprises the following steps:
One, determining instrument and reagent:
(1) instrument
It include that breeze 1525 is pumped using high performance liquid chromatograph (waters company), 2487 dual wavelength ultraviolet detectors,
Nova-Pak SiO2Chromatographic column (604 μm of 3.9x150mm, id, waters company), analysis software are empower；
(2) reagent
Standard sample TDI is purchased from Bayer company, Germany；Mobile phase 2,2,4- trimethylpentane and 1,4- dioxane
For high-efficiency liquid chromatographic-grade reagent, it is purchased from Merck KGaA company；
Two, in TDI base polyurethane prepolymer for use as low-free TDI quantitative analysis
(1) configuration of standard solution
TDI standard reagent 10mg-1g is accurately weighed, is placed in the volumetric flask of 100ml, initial flow phased soln is added and is diluted
It to scale, shakes up, as standard solution stock solution, takes above-mentioned stock solution 0.5ml, 1ml, 1.5ml, 2ml, 3ml, 5ml respectively, use
Initial flow phase dilution constant volume is configured to 6 standard solution into the volumetric flask of 50ml, for doing standard quantitative curve；
(2) sample to be tested configures
Accurately weighing quality is MSampleSample to be tested, be configured to prepare liquid, volume V with initial flow phased solnSample, to be measured
The concentration range of liquid is 20mg/ml-100mg/ml；
(3) it measures
(a) standard solution measures
The absorption value of each standard solution is measured, standard curve is drawn, two absorption values of each METHOD FOR CONTINUOUS DETERMINATION take its average value
As a result, taking 10 μ l to carry out gradient elution, initial flow with high performance liquid chromatograph respectively 6 standard solution of above-mentioned configuration
Dynamic phase is 2,2, the 4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane that volume ratio is 75:25, and mobile phase is direct when being eluted to 4 minutes
Isosorbide-5-Nitrae-the dioxane for becoming 100% changes to 2,2,4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane when by 10 minutes again
Mixed liquor, volume ratio 75:25, flow velocity 0.6ml/min, chromatogram column temperature is 25 DEG C, and UV detector Detection wavelength can be
220nm to 237nm, obtaining standard curve by integral area and concentration is y=a+bx；
(b) prepare liquid measures
It with gradient elution, initial liquid phase is carried out on high performance liquid chromatograph is body that the prepare liquid of above-mentioned configuration, which is taken 10 μ l,
Product is than 2,2, the 4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane that are 75:25, and mobile phase directly becomes when being eluted to 4 minutes
100% Isosorbide-5-Nitrae-dioxane, changes to 2,2,4- trimethylpentanes again when by 10 minutes and Isosorbide-5-Nitrae-dioxane is mixed
Liquid is closed, volume ratio 75:25, flow velocity 0.6ml/min, chromatogram column temperature is 25 DEG C, and UV detector Detection wavelength can be 220nm
To 237nm, free TDI concentration in prepare liquid is obtained by TDI standard curve using empower software, measurement is averaged twice
CSample；
(4) it calculates
Pass through formula, free TDI %=CSample╳VSample/MSampleQuality of the free TDI in performed polymer is calculated in ╳ 100%
Percentage.
By the test of ultraviolet spectra to TDI solution, obtain three ultraviolet absorption peaks, be 207nm respectively, 237nm and
284nm, but since mobile phase Isosorbide-5-Nitrae-dioxane cutoff wavelength is 215nm, so this patent has selected 220nm, still
Since 284nm absorption peak strength is little, so this patent has selected 220nm-237nm range.
This patent uses gradient elution, is primarily due in base polyurethane prepolymer for use as other than having free TDI, most of
It is polymer, Isosorbide-5-Nitrae-dioxane is big to the solubility of polymer, and eluting power is strong, so can quickly elute completely, no
It will cause residual and hangover.
This patent method has the advantage that compared with the conventional method
1. detection limit is low, high sensitivity, between each component using detecting to the strongest wavelength of TDI UV absorption
Separating degree is big, and testing result is accurate, and detection range is wide.
2. using gradient elution, the testing time is saved, solves the problems, such as chromatographic peak hangover, it is reproducible, make continuously to survey
Multiple samples are tried to be possibly realized.
3. sample is by the processing such as derivative, directly configuration test, lost and process is simple, operation side without intermediate
Just.
Detailed description of the invention
Standard curve of Fig. 1 TDI standard solution in 220nm wavelength.
The high-efficient liquid phase chromatogram that Fig. 2 performed polymer LF950A is obtained in 220nm ultraviolet wavelength gradient elution.
The high-efficient liquid phase chromatogram that Fig. 3 performed polymer LF800A is obtained in 237nm ultraviolet wavelength gradient elution.
The high-efficient liquid phase chromatogram that Fig. 4 performed polymer LF800A is obtained in 254nm ultraviolet wavelength isocratic elution.
The high-efficient liquid phase chromatogram that Fig. 5 performed polymer LF800A is obtained in 220nm ultraviolet wavelength gradient elution.
Table 1LF800A sample is in six measurement results of 220nm and 254nm Detection wavelength and relative standard deviation.
Specific embodiment:
Embodiment 1:
(1) instrument
It include that breeze 1525 is pumped using high performance liquid chromatograph (waters company), 2487 dual wavelength ultraviolet detectors,
Nova-Pak SiO2Chromatographic column (604 μm of 3.9x150mm, id, waters company), analysis software are empower；
(2) reagent
Standard sample TDI is purchased from Bayer company, Germany；Mobile phase 2,2,4- trimethylpentane and 1,4- dioxane
For high-efficiency liquid chromatographic-grade reagent, it is purchased from Merck KGaA company；
(3) measurement of standard curve
TDI standard reagent 0.0980g to 100ml volumetric flask is accurately weighed, initial flow phased soln is added, is configured to standard
Solution stock solution.Then above-mentioned stock solution 0.5ml, 1ml, 1.5ml, 2ml, 3ml are taken respectively, and 5ml is dissolved into initial liquid phase
Configuration standard series, takes 10 μ l of each standard serial solution to carry out ladder with high performance liquid chromatograph respectively in the volumetric flask of 50ml
Degree elution, initial liquid phase are 2,2, the 4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane that volume ratio is 75:25, are eluted to 4 points
Mobile phase directly becomes 100% Isosorbide-5-Nitrae-dioxane when clock, changed to again when by 10 minutes 2,2,4- trimethylpentanes and
Isosorbide-5-Nitrae-dioxane mixed liquor, volume ratio 75:25.Flow velocity 0.6ml/min, chromatogram column temperature are 25 DEG C, UV detector
Detection, wavelength can be 220nm, and obtaining standard curve by integral area and concentration is y=228351+98750x, R2=0.9992,
Standard curve is shown in Fig. 1.
(4) sample to be tested measures
It is fixed with flowing phased soln to accurately weigh 2.8148g sample LF950A (Chemtura Corporation, free TDI≤0.1wt%)
Hold in 50ml volumetric flask and obtains prepare liquid.10 μ l of prepare liquid is taken to carry out gradient elution, starting stream with high performance liquid chromatograph
Dynamic phase is 2,2, the 4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane that volume ratio is 75:25, and mobile phase is direct when being eluted to 4 minutes
Isosorbide-5-Nitrae-the dioxane for becoming 100% changes to 2,2,4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane when by 10 minutes again
Mixed liquor, volume ratio 75:25.Flow velocity 0.6ml/min, chromatogram column temperature are 25 DEG C, UV detector detection, and wavelength can be
220nm, the chromatogram measured are shown in Fig. 2, it can be seen that the peak of TDI component can achieve baseline separation, pass through peak area external standard method
Quantitative, the concentration measured twice in succession is 25.34ug/ml and 25.13ug/ml, and free TDI monomer is obtained by calculation and exists
Content in performed polymer is 0.045wt%.
Embodiment 2:
It is fixed with flowing phased soln to accurately weigh 4.7148g sample LF800A (Chemtura Corporation, free TDI≤0.1wt%)
Hold in 50ml volumetric flask and obtains prepare liquid.Using high performance liquid chromatograph gradient elution, ultraviolet detection wavelength 237nm is obtained
Chromatogram is shown in Fig. 3, it can be seen that the peak of TDI component can achieve baseline separation, by peak area quantified by external standard method, obtain continuous
The concentration measured twice is 28.32ug/ml and 28.26ug/ml, and content of the free TDI monomer in performed polymer, which is calculated, is
0.030%.Remaining is the same as embodiment 1.
Embodiment 3:
It is fixed with flowing phased soln to accurately weigh 1.0215g sample LF950A (Chemtura Corporation, free TDI≤0.1wt%)
Hold in 50ml volumetric flask and obtains prepare liquid.By prepare liquid inject liquid chromatograph gradient elution, ultraviolet detection wavelength 220nm,
The peak of TDI component can achieve baseline separation, by peak area quantified by external standard method, obtain free TDI monomer in performed polymer
Content is 0.043%.Remaining is the same as embodiment 1.
Embodiment 4:
It is fixed with flowing phased soln to accurately weigh 2.8148g sample LF950A (Chemtura Corporation, free TDI≤0.1wt%)
Hold in 50ml volumetric flask and obtains prepare liquid.By prepare liquid inject liquid chromatograph gradient elution, ultraviolet detection wavelength 230nm,
The peak of TDI component can achieve baseline separation, by peak area quantified by external standard method, obtain free TDI monomer in performed polymer
Content is 0.045%.
Embodiment 5:
It is fixed with flowing phased soln to accurately weigh 4.7148g sample LF800A (Chemtura Corporation, free TDI≤0.1wt%)
Hold in 50ml volumetric flask and obtains prepare liquid.Using high performance liquid chromatograph gradient elution, ultraviolet detection wavelength 220nm is obtained
Chromatogram is shown in Fig. 5, remaining is the same as embodiment 1.Using external standard method peak area quantification, the average result and opposite mark of six measurements are obtained
Quasi- deviation RSD is shown in Table 1.
Comparative example 1:
It is fixed with flowing phased soln to accurately weigh 4.7148g sample LF800A (Chemtura Corporation, free TDI≤0.1wt%)
Hold in 50ml volumetric flask and obtains prepare liquid.Prepare liquid injects high performance liquid chromatograph, using the method in document, 2,2,4-
4:1 isocratic elution, ultraviolet detection wavelength 254nm obtain liquid chromatogram by volume for trimethylpentane and Isosorbide-5-Nitrae-dioxane
See Fig. 4.Using peak height quantified by external standard method, the average result and relative standard deviation RSD that six measurements obtain are shown in Table 1.From figure
It can be seen that the peak of TDI component and the separating degree at other peaks are smaller, the chromatographic peak peak height response of component TDI is very small, test
As a result sensitivity and separating degree are all bad, and error is very big when quantitatively calculating, and six test results show that repeatability is bad.Separately
Outside, the testing time is long, is eluted to 15 minutes and does not also elute completely.
From figure 5 it can be seen that the separating degree at the peak of TDI component and other peaks is big in embodiment 5, response is very big,
Absorption value is three times of comparative example 1, and the sensitivity of test result and separating degree are all high, and six test results show reproducible.
And at 8 minutes, all components can be eluted out in performed polymer, save elution time.
1 LF800A sample of table is in six measurement results of 220nm and 254nm Detection wavelength and relative standard deviation
Claims (1)
1. a kind of method of low free toluene diisocyanate content in measurement base polyurethane prepolymer for use as, it is characterised in that including as follows
Step:
Determining instrument and reagent:
(1) instrument
It is pumped using high performance liquid chromatograph, including breeze 1525,2487 dual wavelength ultraviolet detectors, 3.9x150mm,
604 μm of id of Nova-Pak SiO2Chromatographic column, analysis software are empower；
(2) reagent
Standard sample TDI is purchased from Bayer company, Germany；Mobile phase 2,2,4- trimethylpentane and 1,4- dioxane are
High-efficiency liquid chromatographic-grade reagent is purchased from Merck KGaA company；
The quantitative analysis of low-free TDI in TDI base polyurethane prepolymer for use as
(1) configuration of standard solution
TDI standard reagent 10mg-1g is accurately weighed, is placed in the volumetric flask of 100ml, initial flow phased soln is added and is diluted to
Scale shakes up, and as standard solution stock solution, takes above-mentioned stock solution 0.5ml, 1ml, 1.5ml, 2ml, 3ml, 5ml respectively, with first
Flowing phase dilution constant volume begin into the volumetric flask of 50ml, 6 standard solution are configured to, for doing standard quantitative curve；
(2) sample to be tested configures
Accurately weighing quality is MSampleSample to be tested, be configured to prepare liquid, volume V with initial flow phased solnSample, prepare liquid
Concentration range is 20mg/ml-100mg/ml；
(3) it measures
(a) standard solution measures
The absorption value of each standard solution is measured, standard curve is drawn, two absorption values of each METHOD FOR CONTINUOUS DETERMINATION take its average value conduct
As a result, taking 10 μ l to carry out gradient elution, initial liquid phase with high performance liquid chromatograph respectively 6 standard solution of above-mentioned configuration
It is 2,2, the 4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane that volume ratio is 75:25, mobile phase directly becomes when being eluted to 4 minutes
100% Isosorbide-5-Nitrae-dioxane changes to 2,2,4- trimethylpentanes and the mixing of Isosorbide-5-Nitrae-dioxane when by 10 minutes again
Liquid, volume ratio 75:25, flow velocity 0.6ml/min, chromatogram column temperature are 25 DEG C, and UV detector Detection wavelength can be for 220nm extremely
237nm, obtaining standard curve by integral area and concentration is y=a+bx；
(b) prepare liquid measures
It with gradient elution, initial liquid phase is carried out on high performance liquid chromatograph is volume ratio that the prepare liquid of above-mentioned configuration, which is taken 10 μ l,
It is the 2 of 75:25,2,4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane, mobile phase directly becomes the 1 of 100% when being eluted to 4 minutes,
4- dioxane changes to 2,2,4- trimethylpentanes and Isosorbide-5-Nitrae-dioxane mixed liquor, volume when by 10 minutes again
Than for 75:25, flow velocity 0.6ml/min, chromatogram column temperature is 25 DEG C, UV detector Detection wavelength can be 220nm to 237nm,
Free TDI concentration in prepare liquid is obtained by TDI standard curve using empower software, measurement is averaged C twiceSample；
(4) it calculates
Pass through formula, free TDI %=CSample╳VSample∕MSampleMass percent of the free TDI in performed polymer is calculated in ╳ 100%.
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| CN106596772B (en) * | 2016-12-14 | 2019-07-12 | 广州天赐高新材料股份有限公司 | The detection method of state double bond compound is built up in a kind of lithium hexafluoro phosphate electrolyte solution |
| CN108279276A (en) * | 2017-03-10 | 2018-07-13 | 泰州市产品质量监督检验中心 | The assay method of toluene di-isocyanate(TDI) residual quantity in a kind of sponge brassiere |
| CN110068616B (en) * | 2018-01-22 | 2022-06-03 | 联化科技股份有限公司 | Normal phase chromatographic analysis method for 4-chlorine-2 nitrophenyl isocyanate and reaction liquid thereof |
| CN111521695B (en) * | 2020-04-14 | 2022-09-16 | 中国建材检验认证集团苏州有限公司 | Method for rapidly detecting free toluene diisocyanate in polyurethane coating |
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| CN105367743A (en) * | 2015-12-21 | 2016-03-02 | 中国科学院山西煤炭化学研究所 | Synthetic method of waterborne polyurethane emulsion |
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| CN105367743A (en) * | 2015-12-21 | 2016-03-02 | 中国科学院山西煤炭化学研究所 | Synthetic method of waterborne polyurethane emulsion |
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| 用液相色谱(HPLC)测定聚氨酯预聚物中的游离TDI;汪世平 等;《上海涂料》;19961231(第2期);摘要，第86-87页 * |
| 空气中TDI的滤膜采集和HPLC测定法的实验研究;崔强 等;《职业与健康》;20051231;第21卷(第12期);全文 * |
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