CN109917029A - A kind of measuring method of aliphatic polyether functionality polyols and distribution - Google Patents
A kind of measuring method of aliphatic polyether functionality polyols and distribution Download PDFInfo
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Abstract
The present invention relates to a kind of aliphatic polyether functionality polyols and the measuring methods of Functionality distribution, using column front derivation-laser light scattering (LLS)/refractive power (RI)/ultraviolet (UV) three detector gel permeation chromatography (GPC) measurement aliphatic polyether functionality polyols and its distribution, the polymer fractions of gel chromatography post separation different molecular weight, the parameters such as fractionated molecule amount at different levels, weight, hydroxy radical content are directly measured using a variety of detectors, improve the accuracy of test result.The present invention also has detection method easy to implement, the good advantage of data redundancy.The present invention is conducive to the consistency for controlling polyurethane industrial chinese raw materials batch performance, promotes the quality stability of product for polyether polyols alcohol functionalities and the measurement of distribution.
Description
Technical field
The present invention relates to a kind of aliphatic polyether functionality polyols and the measuring methods of Functionality distribution, specifically
It is a kind of using multi-detector-gel permeation chromatography (GPC) measurement aliphatic polyether functionality polyols and Functionality distribution
Method.
Background technique
Aliphatic poly ethoxylated polyhydric alcohol is the important raw material of polyurethane industrial, is widely applied and building, machinery, food, spinning
It knits, the fields such as national defence.Such as end hydroxy butadiene (HTPB), simple production process, viscosity are low, can obtain high solids content solid
Propellant, it has also become the widely used adhesive kind of countries in the world composite solidpropellant.HTPB average functionality is about 2,
But its Functionality distribution has certain dispersibility.The degree of functionality and Functionality distribution of HTPB influences its curing activity and crosslinking elasticity
The mechanical property of body, therefore the difference between adhesive batch will lead to Product Process performance, mechanical property poor repeatability.Therefore,
Quantitative, accurate characterization aliphatic poly ethoxylated polyhydric alcohol degree of functionality and distribution are needed in the industrial production.
U.S. AIAA meeting paper 78-122 reports document " Functionality Determination in
Hydroxyl-Terminated Prepolymers ", this document propose obtain terminal hydroxy group pre-polymerization using gel point test data
The method of object number-average.
Britain's periodical " British Polymer Journal " the 1st phase in 1985 reports document " The Molecular
Characteristics of Hydroxyl-terminated Polybutadiene ", this document propose tried using gel
It is equal in conjunction with vapour pressure penetration testing (VPO) measurement number to propose infrared spectroscopy (IR) for the method that HTPB effective functionality is determined in test
The method of degree of functionality.
U.S.'s periodical " Journal of Applied Polymer Science " 1975 volume 19 reports document
“Functionality Distribution of Hydroxyl-terminated Polybutadiene Using Gel
Permeation Chromatography ", this document propose seeped using differential refraction/ultraviolet (RI/UV) dual detector gel
Saturating chromatography for simultaneous detection HTPB molecular weight, molecular weight distribution, the method for average functionality, Functionality distribution.
Chinese periodical " orchidization science and technology " the 1st phase in 1994 report document " GPC measure end hydroxy butadiene degree of functionality and
Molecular weight distribution ", this document propose after derivatization reaction with it is ultraviolet/show that poor (UV/RI) dual detector GPC measures the poly- fourth of terminal hydroxy group
The method of the degree of functionality of diene, Functionality distribution and molecular weight distribution.
Chinese periodical " chemical propellant and high molecular material " the 5th phase in 2009 reports document " end hydroxy butadiene
The measurement of degree of functionality and distribution ", the document equally using it is ultraviolet/show that poor (UV/RI) dual detector GPC determines the poly- fourth of terminal hydroxy group
The degree of functionality and its distribution of diene.
Document disclosed above is reflected using HTPB as the aliphatic polyether functionality polyols of representative and its distribution tests side
The state of the art of method.Using it is ultraviolet described in document/to show that poor (UV/RI) dual detector GPC method can measure aliphatic polyether more
The degree of functionality and its distribution of first alcohol, however this method has the following deficiencies: the molecular weight of different fractions aliphatic poly ethoxylated polyhydric alcohol
The calibrating curve determining established by GPC method according to molecular weight standard sample is a kind of relative determination method, leads to Functionality distribution
Measurement result depends on the selection of GPC molecular weight standards;The correction of UV detector uses area normalization method, that is, assumes all
Aliphatic polyether polyol molecule chain has functional group after derivative, does not consider influence of the zero degree of functionality component to measurement result.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of aliphatic polyether functionality polyols and the measurement sides of distribution
Method, measurement aliphatic polyether polyol molecular weight that can be absolute are effective to measure degree of functionality and its distribution, accuracy, repetition
Property is higher.
To solve, the present invention is realized using following technical scheme: a kind of aliphatic polyether is polynary
The measuring method of alcohol functionalities and distribution is detected using column front derivation-laser light scattering (LLS)/refractive power (RI)/ultraviolet (UV) three
The method that device GPC method measures aliphatic polyether functionality polyols and its distribution, detection process are as follows:
(1) derivative reaction of polyether polyol
Derivating agent used is 3,5- dinitrobenzoyl chloride, converts the group with UV absorption for hydroxyl, sample is made to have foot
Enough UV absorptions, derivatization reaction formula are
;
Specific derivatization process is that have polyether polyol sample and derivating agent DNBC 3,5 dinitrobenzoylchloride in catalyst pyridine
Under, it is reacted in tetrahydrofuran solution, control acid chloride groups (- COCl) and hydroxyl (- OH) molar ratio are 1.5 ~ 2.0, reaction temperature
Degree is 60 ± 2 DEG C, and the reaction time is 20 ~ 30 minutes;After fully reacting, evaporation of solvent;After residue ether dissolution, use
The sodium bicarbonate solution of mass fraction 5% is washed 2 times, is then washed with deionized water again 2 times.Evaporation removes ether, after being derived
Polyether polyol sample;
(2) calibration of RI, UV detector
Complete polyether polyol sample will be derived, a series of standard sample solution of various concentrations is configured using tetrahydrofuran,
Sample introduction demarcates the detector response factor;The response intensity relation curve of sample introduction concentration and RI detector is drawn, fitting data obtains
Calibration curve between RI detector response and concentration;Standard polyether polyol sample is calculated according to the hydroxyl value of chemical titration
Product solution hydroxyl concentration, draws the response intensity relation curve of sample introduction hydroxyl concentration and UV detector, and fitting data obtains UV inspection
Survey the calibration curve between device response and hydroxyl concentration;
(3) polyether polyol Functionality distribution is tested
Polyether polyol sample after derivative is configured to the sample solution that concentration is the mg/mL of 10mg/mL ~ 30, sample introduction is tested, by
LLS detector signal calculates the molecular weight of each fractionM wi ;According to the relationship between RI detector response and polyether polyols determining alcohol
The concentration for calculating each fraction calculates at different levels points of weight in conjunction with detection cell volumeW i ;According to UV detector response and hydroxyl concentration
Between relationship calculate the hydroxyl concentration of each fraction, at different levels points of hydroxy number is calculated in conjunction with detection cell volumeK OHi , by following formula meter
Calculate the hydroxy functionality of each fractionf wi
(1)
Test philosophy schematic diagram such as Fig. 2, the delay time between detector、Pass through polystyrene (PS) narrow ditribution mark
Sample determines;
Weighted Average Functionality are as follows:
(2)
A iIt is in RI absorption peakiThe peak area of fraction can replace meter when the sampling interval is fixed with the peak height approximation of the fraction
It calculates;
The number-average of polyether polyolIt is defined as number-average molecular weightWith its total hydroxyl valueProduct:
(3)
WhereinIt is measured with VPO method,It is measured by chemical titration;
Functionality distribution index are as follows:
(4)
Wherein, the aliphatic poly ethoxylated polyhydric alcohol is the polyether prepolymer that end group is hydroxyl, does not contain phenyl ring in molecular structure
Deng the group for having absorption in ultraviolet region.
The derivating agent is 3,5- dinitrobenzoyl chloride, other can also be made to contain aromatic group and can be with hydroxyl
The compound of fast reaction group, reactive group can be one of acyl halide group, anhydride group, isocyanate groups.
The derivatization reaction, catalyst are pyridine, and reaction dissolvent is tetrahydrofuran, and reaction temperature is 50 DEG C ~ 70 DEG C,
Reaction time is 20 ~ 30 minutes, and product ether dissolution after reaction successively cleans 2 ~ 3 with sodium bicarbonate solution, deionized water
It is secondary.
The method of-three detector GPC method of the column front derivation measurement polyether polyols alcohol functionalities and its distribution, GPC points
From condition are as follows: crosslinked polystyrene gel chromatographic column, mobile phase are tetrahydrofuran, and detector is UV detector, multi-angle swashs
Light light scattering detector, differential refraction detector.
The method of-three detector GPC method of the column front derivation measurement polyether polyols alcohol functionalities and its distribution, difference point
The molecular weight of sub- magnitude point is directly measured using multi-angle laser light scattering detector, and fraction weight uses differential refraction detector
It is detected using UV detector by quantified by external standard method by quantified by external standard method detection, fraction hydroxy radical content.
The advantages and effects of the present invention are:
The present invention mainly passes through column front derivation-laser light scattering (LLS)/refractive power (RI)/ultraviolet (UV) three detector GPC method and surveys
Determine polyether polyols alcohol functionalities and its distribution, the polymer fractions of gel chromatography post separation different molecular weight, using a variety of detections
Device directly measures the parameters such as fractionated molecule amount at different levels, weight, hydroxy radical content, improves the accuracy of test result.The present invention also has
Have that detection method is easy to implement, the good advantage of data redundancy.The present invention is used for the measurement of polyether polyols alcohol functionalities and distribution,
The consistency for being conducive to control polyurethane industrial chinese raw materials batch performance, promotes the quality stability of product.
Detailed description of the invention
Fig. 1 is degree of functionality and its distribution tests schematic illustration.
Calibration curve of the Fig. 2 between RI detector response and HTPB concentration.
Calibration curve of the Fig. 3 between UV detector response and HTPB hydroxyl concentration.
Fig. 4 is the typical spectrogram of the derivative sample of HTPB.
Fig. 5 is the Functionality distribution curve of typical case HTPB.
Specific embodiment
The present invention is further elaborated combined with specific embodiments below, but does not limit the present invention.
In the following embodiments, using column front derivation-laser light scattering (LLS)/refractive power (RI)/ultraviolet (UV) three detector
GPC method measures a kind of common aliphatic poly ethoxylated polyhydric alcohol --- end hydroxy butadiene (HTPB) degree of functionality and its distribution, specifically
Implementation steps are as follows.
Step 1, the derivative reaction of polyether polyol.By 1g HTPB sample and excessive DNBC 3,5 dinitrobenzoylchloride
It in the presence of catalyst pyridine, is reacted in 25mL tetrahydrofuran solution, reaction temperature is 60 ± 2 DEG C, and the reaction time is 30 points
Clock.After fully reacting, evaporation of solvent.After residue ether dissolution, 2 are washed with the sodium bicarbonate solution of mass fraction 5%
It is secondary, it is then washed with deionized water again 2 times.Evaporation removes ether, and obtaining light yellow dope is the HTPB sample after deriving.
Step 2, the calibration of RI, UV detector.Complete HTPB sample will be derived, it is a series of not using tetrahydrofuran configuration
With the standard sample solution of concentration, sample introduction demarcates the detector response factor.Draw the response intensity of sample introduction concentration and RI detector
Relation curve, fitting data obtain the calibration curve (Fig. 2) between RI detector response and concentration;It is surveyed according to chemical titration
Fixed hydroxyl value calculates standard polyether polyol sample solution hydroxyl concentration, draws sample introduction hydroxyl concentration and the response of UV detector is strong
Relation curve is spent, fitting data obtains the calibration curve (Fig. 3) between UV detector response and hydroxyl concentration.Calibration curveR 2
It is all larger than 0.99, good relationship.
Step 3, HTPB degree of functionality and its distribution tests.It is 15 mg/ that polyether polyol sample after derivative, which is configured to concentration,
The sample solution of mL, sample introduction test, sample spectrogram are shown in Fig. 4.The molecular weight of each fraction is calculated by LLS detector signalM wi ;According to
Relationship between RI detector response and polyether polyols determining alcohol calculates the concentration of each fraction, calculates in conjunction with detection cell volume at different levels
The weight dividedW i ;The hydroxyl concentration that each fraction is calculated according to the relationship between UV detector response and hydroxyl concentration, in conjunction with detection
Pond body product calculates the hydroxy number of each fractionK OHi , according to formula (1) calculate each fraction hydroxy functionalityf wi , HTPB can be drawn
The Functionality distribution curve of sample, is shown in Fig. 5.
Calculating HTPB sample Weighted Average Functionality by formula (2) is 2.82.Selected batch HTPB sample number-average molecular weight=
3260, hydroxyl valueK OH=0.690mmol/g calculates number-average according to formula (3)=2.25.Functionality distribution is calculated by formula (4)
IndexD f =1.25。
7 Functionality distribution tests are carried out to selected HTPB sample, Weighted Average Functionality and profile exponent measurement result are opposite
Standard deviation is respectively 2.12%, 2.25%, and precision is good.
The above described is only a preferred embodiment of the present invention, not making any form to technical solution of the present invention
On limitation.According to the technical essence of the invention any simple modification to the above embodiments, equivalent variations and repair
Decorations, fall within the protection scope of the present invention.
Claims (6)
1. the measuring method of a kind of aliphatic polyether functionality polyols and distribution, using column front derivation-laser light scattering LLS/
The method that three detector GPC method of refractive power RI/ UV UV measures aliphatic polyether functionality polyols and its distribution, detection process
Are as follows:
(1) derivative reaction of polyether polyol
Derivating agent used is 3,5- dinitrobenzoyl chloride, converts the group with UV absorption for hydroxyl, sample is made to have foot
Enough UV absorptions, derivatization reaction formula are
;
Specific derivatization process is that have polyether polyol sample and derivating agent DNBC 3,5 dinitrobenzoylchloride in catalyst pyridine
Under, it is reacted in tetrahydrofuran solution, control acid chloride groups-COCl and hydroxyl-OH molar ratio are 1.5 ~ 2.0, and reaction temperature is
60 ± 2 DEG C, the reaction time is 20 ~ 30 minutes;After fully reacting, evaporation of solvent;After residue ether dissolution, quality is used
The sodium bicarbonate solution of score 5% is washed 2 times, is then washed with deionized water again 2 times, and evaporation removes ether, poly- after being derived
Ethoxylated polyhydric alcohol sample;
(2) calibration of RI, UV detector
Complete polyether polyol sample will be derived, a series of standard sample solution of various concentrations is configured using tetrahydrofuran,
Sample introduction demarcates the detector response factor;The response intensity relation curve of sample introduction concentration and RI detector is drawn, fitting data obtains
Calibration curve between RI detector response and concentration;Standard polyether polyol sample is calculated according to the hydroxyl value of chemical titration
Product solution hydroxyl concentration, draws the response intensity relation curve of sample introduction hydroxyl concentration and UV detector, and fitting data obtains UV inspection
Survey the calibration curve between device response and hydroxyl concentration;
(3) polyether polyol Functionality distribution is tested
Polyether polyol sample after derivative is configured to the sample solution that concentration is the mg/mL of 10mg/mL ~ 30, sample introduction is tested, by
LLS detector signal calculates the molecular weight of each fractionM wi ;According to the relationship between RI detector response and polyether polyols determining alcohol
The concentration for calculating each fraction calculates at different levels points of weight in conjunction with detection cell volumeW i ;According to UV detector response and hydroxyl concentration
Between relationship calculate the hydroxyl concentration of each fraction, at different levels points of hydroxy number is calculated in conjunction with detection cell volumeK OHi , by following formula meter
Calculate the hydroxy functionality of each fractionf wi
(1)
Test philosophy schematic diagram such as Fig. 2, the delay time between detector、It is true by polystyrene narrow standards
It is fixed;
Weighted Average Functionality are as follows:
(2)
A iIt is in RI absorption peakiThe peak area of fraction can replace meter when the sampling interval is fixed with the peak height approximation of the fraction
It calculates;
The number-average of polyether polyolIt is defined as number-average molecular weightWith its total hydroxyl valueProduct:
(3)
WhereinIt is measured with VPO method,It is measured by chemical titration;
Functionality distribution index are as follows:
(4).
2. measuring method according to claim 1, it is characterised in that: it is hydroxyl that the aliphatic poly ethoxylated polyhydric alcohol, which is end group,
The polyether prepolymer of base has the group of absorption in ultraviolet region without containing phenyl ring etc. in molecular structure.
3. measuring method according to claim 1, it is characterised in that: the derivating agent is 3,5- dinitro benzoyl
Chlorine, or other is made to contain aromatic group and can be acyl halide group, acid with the compound of hydroxyl fast reaction group, reactive group
One of anhydride group, isocyanate groups.
4. measuring method according to claim 1, it is characterised in that: the derivatization reaction, catalyst are pyridine, instead
Answering solvent is tetrahydrofuran, and reaction temperature is 50 DEG C ~ 70 DEG C, and the reaction time is 20 ~ 30 minutes, and product ether is molten after reaction
Solution, is successively cleaned 2 ~ 3 times with sodium bicarbonate solution, deionized water.
5. measuring method according to claim 1, it is characterised in that: the GPC separation condition is crosslinked polystyrene
Gel chromatographic columns, mobile phase are tetrahydrofuran, and detector is UV detector, multi-angle laser light scattering detector, shows poor folding
Photodetector.
6. measuring method according to claim 1, it is characterised in that:-three detector GPC method of the column front derivation measurement
The molecular weight of the method for polyether polyols alcohol functionalities and its distribution, different molecular weight fraction is detected using multi-angle laser light scattering
Device directly measures, and fraction weight is using differential refraction detector by quantified by external standard method detection, fraction hydroxy radical content using ultraviolet
Detector is detected by quantified by external standard method.
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CN112505203A (en) * | 2020-12-08 | 2021-03-16 | 杭州师范大学 | Method for quantifying trace silicon hydroxyl in silicone oil |
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