Disclosure of Invention
In order to solve the problems, the invention provides a method for measuring the trace acid value of a photoacid generator. The method comprises the following steps:
(1) preparing 0.005-0.01mol/L NaOH or KOH solution;
(2) accurately measuring or preparing the same solvent with the same volume according to the set parts;
(3) blank determination: weighing 5-10 free acid standard samples, wherein the weight range of the free acid standard samples is 1.000-10.000g, and then preparing a free acid solution corresponding to the parts of the free acid standard samples by using the solvent in the step (2); carrying out potentiometric titration on the free acid solution by using NaOH or KOH titrant prepared in the step (1) respectively to obtain a curve, and calculating the amount of acid in the blank according to the curve;
(4) and (3) sample determination: accurately weighing 5.000-10g of photoacid generator sample, weighing a free acid standard sample according to the method in the step (3), adding the photoacid generator sample into the solvent in the step (2), and uniformly dispersing to obtain a photoacid generator sample solution, wherein the weight ratio of the photoacid generator sample to the solvent is 1: 10-200 parts of the photoacid generator sample solution are the same as the free acid standard samples, the free acid standard samples are correspondingly added into the photoacid generator sample solution one by one, then the NaOH or KOH titrant prepared in the step (1) is respectively used for carrying out potentiometric titration, a curve is obtained, and the total acid amount in the photoacid generator sample solution when the free acid standard samples are not added is calculated according to the curve;
(5) and (3) calculating: and calculating the acid value in the sample according to the formula and the amount of the sample.
The formula is: acid (A1-A2) M/M,
in the formula, Acid- - -calculating to obtain the Acid value, mol/kg, in the photoacid generator sample;
a1- -calculating the total acid amount, g, in step (4) using standard addition methods
A2- -calculating the amount of acid in the blank in step (3), g, using standard addition methods
m- -mass of the photoacid generator sample referred to in step (4), g
M- -the molar concentration of the free acid standard added in step (3), mol/kg.
Specifically, the photoacid generator in step (4) comprises any one of the substances described by the following general formula:
further, R in the general formula1、R2、R3、R4Independently represent hydrogen, C1-C20Straight or branched alkyl of (2), C3-C20Cycloalkyl of, C4-C20Cycloalkylalkyl or C4-C20Alkyl cycloalkyl or C6-C20Or C wherein one or more hydrogens of the group are substituted by one or more groups selected from halogen, nitro, hydroxy, carboxyl, sulfonic acid, cyano or alkoxy1-C20Straight chain alkyl group of (1), C3-C20Cycloalkyl of, C4-C20Cycloalkylalkyl of (C)4-C20Alkyl cycloalkyl or C7-C20Any one of the aryl groups of (1).
Further, in the general formula, X is null or C1-C5An alkylene group of (a); y is O, S, N-R4Or C-R4Wherein R is4Is hydrogen, C1-C20Straight chain alkyl group of (1), C3-C20Cycloalkyl of, C4-C20Cycloalkylalkyl or C4-C20Any one of the alkyl cycloalkyl groups of (a).
Further, in the formula, Z is trifluoroacetate, tetrafluoroborate, hexafluorophosphate, hexafluoroantimonate, tetrakis (pentafluorophenyl) borate or
Any one of plasma anions, wherein R
3Is hydrogen, C
1-C
20Straight or branched alkyl of (2), C
3-C
20Cycloalkyl of, C
4-C
20Cycloalkylalkyl or C
4-C
20Alkyl cycloalkyl or C
6-C
20Or C wherein one or more hydrogens of the group are substituted by one or more groups selected from halogen, nitro, hydroxy, carboxyl, sulfonic acid, cyano or alkoxy
1-C
20Straight chain alkyl group of (1), C
3-C
20Cycloalkyl of, C
4-C
20Cycloalkylalkyl of (C)
4-C
20Alkyl cycloalkyl or C
7-C
20Any one of the aryl groups of (a);
further, the free acid in the step (3) is
Wherein R is
3Is hydrogen, C
1-C
20Straight or branched alkyl of (2), C
3-C
20Cycloalkyl of, C
4-C
20Cycloalkylalkyl of (5)Or C
4-C
20Alkyl cycloalkyl or C
6-C
20Or C wherein one or more hydrogens of the group are substituted by one or more groups selected from halogen, nitro, hydroxy, carboxyl, sulfonic acid, cyano or alkoxy
1-C
20Straight chain alkyl group of (1), C
3-C
20Cycloalkyl of, C
4-C
20Cycloalkylalkyl of (C)
4-C
20Alkyl cycloalkyl or C
7-C
20Any one of the aryl groups of (a);
further, the concentration of the free acid is 0.001-0.005 mol/kg;
further, the solvent used in the step (2) is an organic solvent which is liquid at normal temperature and normal pressure, and the organic solvent does not react with the free acid and the photoacid generator; for example, it may be any one or more of acetonitrile, halogenated hydrocarbon, benzene, substituted benzene, tetrahydrofuran, acetone, alkane, ethyl acetate, butyl acetate, or alkyl ether.
Further, a standard addition method and a potentiometric titration method are combined for use, and the electrode is a non-aqueous phase composite acid-base intelligent pH electrode.
Compared with the prior art, the invention achieves the following technical effects: 1) by using a potentiometric titration method and a standard addition method, detection interference is eliminated; 2) the proper detection reagent and conditions are matched and selected, so that the measurement result of the trace acid value is more accurate and reliable; 3) meets the acid value detection requirement of the photoacid generator which is decomposed by alkali.
Detailed Description
The present invention is not limited to the following embodiments, and those skilled in the art can implement the present invention in other embodiments according to the disclosure of the present invention, or make simple changes or modifications on the design structure and idea of the present invention, and fall into the protection scope of the present invention. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
Firstly, the method of the invention is verified:
5 parts of the same solvent (50ml of dichloromethane and 50ml of acetonitrile) with the same volume are prepared, stirred uniformly, accurately weighed standard solutions (calculated according to actual concentration) of 0.002mol/kg of trifluoromethanesulfonic acid (2.000 g, 4.000g, 5.000g, 8.000g and 10.000 g) are added respectively, and then titrated with a standard solution of 0.005mol/L NaOH in sequence, and the amount of acid in the blank solvent is determined according to a standard addition method.
The same solvent (50ml dichloromethane and 50ml acetonitrile) with the same volume is prepared by 5 parts, stirred evenly, added with accurately weighed standard solution (calculated according to actual concentration) of 0.002mol/kg trifluoromethanesulfonic acid of 2.000g, 4.000g, 5.000g, 8.000g and 10.000g respectively, titrated by 0.005mol/L NaOH standard solution in sequence, and the acid amount in the blank solvent is measured according to the standard addition method.
The experimental results are as follows:
in the table, the recovery rate of acid value is (total acid amount-blank acid amount) × 100%/the amount of the standard sample, the standard sample means the mass of the added 0.002mol/kg of the standard solution of trifluoromethanesulfonic acid, and the amount of the sample means the mass of the added photoacid generator.
From the results, the results of the method after the sample is continuously used for 5 times and adjusted are all between 80% and 120%, and the range of the parallel sample is within 5%, so that the test requirements are met.
The invention is described in more detail below with reference to the following examples:
the calculation of the acid number in the samples in the following examples is as follows:
Acid=(A1-A2)*M/m
acid- - -calculating the Acid value of the sample, mol/kg;
A1-calculating the total acid content, g, in the sample and solvent by standard addition;
A2-calculating the acid content of the solvent, g, by standard addition;
m-the mass of the sample, g;
m- -the molar concentration of the added standard acid, mol/kg;
example 1:
(1) weighing 0.2g of NaOH, putting the NaOH into a polyethylene container, adding 1000mL of carbon dioxide-free water, shaking up to clarify the solution, and preparing 0.005mol/L of NaOH solution;
(2) 50ml of acetonitrile and 50ml of dichloromethane are accurately measured and fully shaken to prepare a mixture of 1: 1, and preparing 10 parts of the mixed solvent for later use;
(3) blank determination: weighing 1.000g, 2.000g, 5.000g, 8.000g and 10.000g of p-toluenesulfonic acid standard sample of 0.002mol/kg, and respectively adding the p-toluenesulfonic acid standard sample into the mixed solvent prepared in the step (2); carrying out potentiometric titration by using NaOH titration solutions respectively to obtain curves (see figure 1), and calculating 0.6043g of acid in the blank according to the curves;
(4) and (3) sample determination: accurately weighing 5 parts of 5.000g photoacid generator
Respectively adding the mixture into the mixed solvent of 50ml acetonitrile and 50ml dichloromethane prepared in the step (2), and respectively adding the mixture into the mixed solvent0.002mol/kg p-toluenesulfonic acid standard 1.000g, 2.000g, 5.000g, 8.000g and 10.000g, respectively carrying out potentiometric titration by using NaOH titration solution, obtaining a curve (see figure 2), and calculating the total acid amount of 1.5848g according to the curve;
(5) and (3) calculating: calculating the acid value of 0.39 x 10 in the sample according to the formula and the amount of the sample-3mol/kg。
Specifically, the method comprises the following steps: taking the value of x as the amount of acid in the solvent when the standard curve y is 0, and A11.5848g (total acid amount in sample and solvent); a. the20.6043g (solvent blank, i.e. the amount of acid in the solvent); m is 0.002 mol/kg; m is 5.0002g, and the acid content in the sample is calculated to be 0.39 x 10-3mol/kg; examples 2 and 3 were the same, and the final data was entered and exited because the amount of sample weighed and the concentration of the standard acid were different.
Example 2
(1) Weighing 0.2g of NaOH, putting the NaOH into a polyethylene container, adding 1000mL of carbon dioxide-free water, shaking up to clarify the solution, and preparing 0.005mol/L of NaOH solution;
(2) 50ml of acetonitrile and 50ml of dichloroethane are accurately measured and fully shaken to prepare a mixture of 1: 1, and preparing 10 parts of the mixed solvent for later use;
(3) blank determination: weighing 1.000g, 2.000g, 5.000g, 8.000g and 10.000g of trifluoromethanesulfonic acid standard sample of 0.002mol/kg, and respectively adding the standard sample into the mixed solvent prepared in the step (2); carrying out potentiometric titration by using NaOH titration solutions respectively to obtain curves (see figure 3), and calculating 0.9592g of acid in the blank according to the curves;
(4) and (3) sample determination: accurately weighing 5 parts of 5.000g photoacid generator
Respectively adding the mixture into a mixed solvent of 50ml of acetonitrile and 50ml of dichloroethane prepared in the step (2), respectively adding 1.000g, 2.000g, 5.000g, 8.000g and 10.000g of 0.002mol/kg of trifluoromethanesulfonic acid standard sample, respectively carrying out potentiometric titration by using NaOH titration solution to obtain a curve (see figure 4), and calculating 2.0673g of total acid amount according to the curve;
(5) and (3) calculating: calculating the acid value of the sample according to the formula and the amount of the sampleIs 0.83 x 10-3mol/kg。
Example 3
(1) Weighing 0.2g of NaOH, putting the NaOH into a polyethylene container, adding 1000mL of carbon dioxide-free water, shaking up to clarify the solution, and preparing 0.005mol/L of NaOH solution;
(2) 50ml of acetone and 50ml of dichloromethane are precisely measured and thoroughly shaken to prepare a mixture of 1: 1, and preparing 10 parts of the mixed solvent for later use;
(3) blank determination: weighing 1.000g, 2.000g, 5.000g, 8.000g and 10.000g of perfluorobutyl sulfonic acid standard sample of 0.002mol/kg, and respectively adding the weighed materials into the mixed solvent prepared in the step (2); carrying out potentiometric titration by using NaOH titration solutions respectively to obtain curves (see figure 5), and calculating 1.0492g of acid in the blank according to the curves;
(4) and (3) sample determination: accurately weighing 5 parts of 5.000g photoacid generator
Respectively adding the mixture into a mixed solvent of 50ml of acetone and 50ml of dichloromethane prepared in the step (2), respectively adding 1.000g, 2.000g, 5.000g, 8.000g and 10.000g of perfluorobutyl sulfonic acid standard sample of 0.002mol/kg, respectively carrying out potentiometric titration by using NaOH titration solution to obtain a curve (see figure 6), and calculating 3.1461g of total acid according to the curve;
(5) and (3) calculating: calculating the acid value of 0.84 x 10 in the sample according to the formula and the amount of the sample-3mol/kg。
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and their concepts should be equivalent or changed within the technical scope of the present invention.