CN113820433A - Method for measuring molecular weight of ethylene propylene diene monomer - Google Patents
Method for measuring molecular weight of ethylene propylene diene monomer Download PDFInfo
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- CN113820433A CN113820433A CN202111305596.2A CN202111305596A CN113820433A CN 113820433 A CN113820433 A CN 113820433A CN 202111305596 A CN202111305596 A CN 202111305596A CN 113820433 A CN113820433 A CN 113820433A
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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
- G01N30/60—Construction of the column
- G01N30/6034—Construction of the column joining multiple columns
- G01N30/6039—Construction of the column joining multiple columns in series
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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
- G01N30/62—Detectors specially adapted therefor
- G01N30/74—Optical detectors
Abstract
The scheme discloses a method for measuring the molecular weight of ethylene propylene diene monomer rubber, which comprises the following steps: (1) weighing a standard sample and a sample to be detected; (2) respectively collecting chromatographic data of a standard sample and chromatographic data of a sample to be detected by a detection instrument; (3) preparing a calibration curve based on chromatographic data of the standard sample; (4) determining molecular weight information of a sample to be detected based on chromatographic data of the sample to be detected and the correction curve; the standard samples are narrow-distribution polystyrene molecular weight standard samples with N different molecular weight levels, and N is an integer greater than or equal to 5; the sample to be detected is an ethylene propylene diene monomer sample to be detected; the detection instrument is a high-temperature gel permeation chromatograph equipped with an infrared detector. The method avoids the problems of unstable baseline, poor result repeatability and the like caused by the change of the refractive index of the universal differential refraction detector due to the influence of temperature, impurities, additives and the like; high temperature dissolution of the sample outside is avoided.
Description
Technical Field
The invention relates to the technical field of analysis and test, in particular to a method for measuring the molecular weight of ethylene propylene diene monomer.
Background
Ethylene propylene diene monomer is terpolymer of ethylene, propylene and non-conjugated diene, has excellent ozone resistance, weather resistance, heat resistance and chemical stability, and is mainly applied to the fields of house construction, wire and cable, automobile industry and the like. The ethylene propylene diene monomer has the lowest density in all rubbers, the highest thermal decomposition temperature, large thermal decomposition heat absorption and large filling coefficient, has excellent compatibility with various propellants and composite shell materials thereof, is an ideal shell heat insulation layer material of a solid rocket motor, and is the most widely applied heat insulation layer variety in the solid rocket motor.
The Mooney viscosity of EPDM is determined in GJB 8797 and 2015ENB type EPDM Standard, and the molecular weight and distribution of EPDM are not determined. The Mooney viscosity has a certain relation with the molecular weight of the sample, can reflect the molecular weight of EPDM, but can not accurately represent the number average molecular weight, the weight average molecular weight and the molecular weight distribution of the sample, and only the Mooney viscosity is used as the control index of the EPDM, so that the method has certain limitation.
The document "laser light scattering method for testing the molecular weight and the distribution of ethylene propylene diene monomer (rubber industry, 2012, 10: 631) 634) proposes a method for measuring the molecular weight and the distribution of the Ethylene Propylene Diene Monomer (EPDM) rubber, which takes toluene as a mobile phase and adopts the laser light scattering method for detection at 25 ℃. When the ethylene content in EPDM is higher, the polymer generally has crystallinity, and a sample contains a small amount of gel due to crystallization or extremely small amount of crosslinking in the dissolving process, so that the sample can be injected by filtration. The molecular weight measured by the laser method is low, the real molecular weight and the distribution thereof cannot be reflected, and the experimental error is large.
In the literature, the molecular weight of long-chain branched EPDM with 1, 2-structure polybutadiene as a third monomer is tested by high-temperature gel permeation chromatography and a high-temperature differential detector in the preparation of EPDM with long-chain branching by an in-situ polymerization method (science and engineering of high polymer materials, 2015,31 (3): 17-21). The method adopts a general type differential refraction detector, and is easily influenced by ambient temperature, mobile phase composition, impurities, additives and the like to generate the change of the refraction coefficient, thereby causing the problems of unstable baseline, poor result repeatability and the like. And the method needs to dissolve the sample at high temperature outside, then the solution is pumped into a filtering device by a needle tube for manual filtration, and then the high-temperature filtrate is manually injected into a GPC sample dissolving bottle and finally transferred into a GPC system. The whole sample preparation process needs manual operation, and the process is very complicated. The manual operation has larger error, and the high-temperature manual operation not only easily causes scald, but also has great harm to the health of people when exposed to high-temperature toxic solvents. The temperature of the sample solution in the manual filtering process can be reduced due to filtering, the sample solution needs to be placed into a sample injector to be preheated again and be injected at a constant temperature, and the sample is repeatedly heated to cause thermal degradation, so that the test result is influenced.
Disclosure of Invention
One purpose of this scheme lies in providing a kind of ethylene propylene diene monomer molecular weight determination method, this method has avoided the general type to show that the refraction index detector is influenced by temperature, impurity, additive, etc. and produced the change of the refraction index, cause the unstable base line, the result repeatability is bad question, etc.; the complicated process that manual operation is needed in the whole process and errors caused by the manual operation are avoided when the sample is dissolved at high temperature outside; the problems of large experimental error caused by inconsistent heating time and high-temperature oxidative degradation of the sample are avoided.
In order to achieve the purpose, the scheme is as follows:
a method for measuring the molecular weight of ethylene propylene diene monomer rubber comprises the following steps:
(1) weighing a standard sample and a sample to be detected;
(2) testing through a detection instrument, and respectively collecting chromatographic data of a standard sample and chromatographic data of a sample to be detected;
(3) preparing a calibration curve based on chromatographic data of the standard sample;
(4) determining molecular weight information of a sample to be detected based on chromatographic data of the sample to be detected and the correction curve;
the standard samples are narrow-distribution polystyrene molecular weight standard samples with N different molecular weight levels, and N is an integer greater than or equal to 5; the sample to be detected is an ethylene propylene diene monomer sample to be detected.
Preferably, the molecular weight distribution of the narrow-distribution polystyrene molecular weight standard sample is 102～107。
Preferably, the sample weighing amount of the standard sample is 10-100 mg; the sample weight of the sample to be detected is 10-20 mg.
Preferably, the chromatographic columns of the high-temperature gel permeation chromatograph adopt a series connection mode, three high-temperature resistant gel permeation chromatographic columns are combined, and the linear range of the column molecular weight of the chromatographic columns is 104～107Column efficiency N > 104Theoretical plate number/m, resolution Rs > 1.5.
Preferably, in the step (2), the sample dissolving and testing temperature set by the high-temperature gel permeation chromatograph is 130-170 ℃, the solvent amount of the dissolved sample is 6-10 ml, and the dissolving time is 45-120 min.
Preferably, in the step (2), the solvent used for dissolving the sample in the test is chromatographically pure 1,2, 4-trichlorobenzene or chromatographically pure o-dichlorobenzene, and the antioxidant 2, 6-di-tert-butyl-p-cresol (BHT) with the content of 0.10g/L to 0.50g/L is dissolved in the solvent.
Preferably, in the step (2), the flow rate of the mobile phase during the test is 0.8 mL/min-1.2 mL/min, and the sample injection amount is 100 muL-300 muL.
Preferably, the calibration curve is prepared by determining the calibration curve according to one or q times of fitting curve of logarithm lgM and retention time t of standard value of number average molecular weight and/or weight average molecular weight of the narrow distribution polystyrene molecular weight standard samples with the N different molecular weight levels, wherein q is less than or equal to 5(ii) a Determination coefficient R of correction curve2≥0.99。
Preferably, the molecular weight information includes a number average molecular weight, a weight average molecular weight value, and a dispersion index.
The scheme has the following beneficial effects:
the molecular weight determination method of Ethylene Propylene Diene Monomer (EPDM) provided by the invention can selectively absorb-CH in polyolefin by selecting a GPC-IR high-temperature gel permeation chromatograph2and-CH3The group has the advantages of good selectivity, strong anti-interference and high sensitivity; the influence of temperature fluctuation on the infrared detector is less, the base line is stable, the base line and the integral limit are better selected during analysis, the accuracy and the repeatability of results are ensured, and the problem of base line drift caused by the change of refractive index of the differential refraction detector due to the influence of temperature, impurities, additives and the like is avoided. And the infrared detector has no micromolecule discrimination and can accurately detect the micromolecule part.
Drawings
In order to illustrate the implementation of the solution more clearly, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the solution, and that other drawings may be derived from these drawings by a person skilled in the art without inventive effort.
FIG. 1 is a diagram showing the test results of samples to be tested in the examples.
Detailed Description
Embodiments of the present solution will be described in further detail below with reference to the accompanying drawings. It is clear that the described embodiments are only a part of the embodiments of the present solution, and not an exhaustive list of all embodiments. It should be noted that, in the present embodiment, features of the embodiment and the embodiment may be combined with each other without conflict.
The terms "first," "second," and the like in the description and in the claims, and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that the embodiments described herein may be practiced otherwise than as specifically illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
The inventor of the application provides a method for measuring the molecular weight of ethylene propylene diene monomer, which comprises the following steps:
(1) n narrow-distribution polystyrene molecular weight standard samples with different molecular weight levels are adopted as external standards for calibration, wherein N is an integer greater than or equal to 5; weighing the narrow-distribution Polystyrene (PS) molecular weight standard sample by 10-100 mg, and respectively placing the narrow-distribution Polystyrene (PS) molecular weight standard sample into sample bottles; weighing an Ethylene Propylene Diene Monomer (EPDM) sample to be detected to be 10-20mg, and respectively placing the sample in sample bottles;
(2) respectively testing the marked sample and the sample to be tested by adopting a high-temperature gel permeation chromatograph, collecting chromatographic data, and placing a sample bottle in a full-automatic sample injector of the high-temperature gel permeation chromatograph, wherein the gel permeation chromatograph sets the sample dissolving temperature, the infrared detector temperature and the column oven temperature to be 130-170 ℃, the solvent quantity for dissolving the sample to be tested is 6-10 ml, and the dissolving time is 45-120 min; the detector and the injection valve of the high-temperature gel permeation chromatograph are positioned in the same insulation box, the gel chromatographic column independently controls the temperature in the column insulation box, three high-temperature resistant gel permeation chromatographic columns are connected in series, and the linear range of the column molecular weight of the chromatographic column is 102～107Column efficiency N > 104The number of theoretical plates per meter and the resolution Rs is more than 1.5;
(3) preparing a calibration curve according to the collected chromatographic data of the N standard samples;
(4) and determining the molecular weight information of the ethylene propylene diene monomer according to the acquired chromatographic data of the sample to be detected and the calibration curve.
In the step (2), the solvent for dissolving the sample to be tested and the mobile phase during the test are all chromatographically pure 1,2, 4-trichlorobenzene dissolved with antioxidant 2, 6-di-tert-butyl-p-cresol (BHT) with the content of 0.10 g/L-0.50 g/L or chromatographically pure o-dichlorobenzene dissolved with antioxidant 2, 6-di-tert-butyl-p-cresol (BHT) with the content of 0.10 g/L-0.50 g/L.
In the step (2), the flow rate of the mobile phase during the test is 0.8 mL/min-1.2 mL/min, and the sample injection amount is 100 muL-300 muL.
The step (3) of preparing the calibration curve according to the N standard samples is to determine the calibration curve according to one or q times of fitting curves of the logarithm lgM of the number average molecular weight and/or weight average molecular weight standard value of the narrow-distribution polystyrene molecular weight standard samples with N different molecular weight levels and retention time t, wherein q is less than or equal to 5; determination coefficient R of correction curve2≥0.99。
The molecular weight information of the ethylene propylene diene monomer in the step (4) comprises the number average molecular weight
Weight average molecular weight value
And a dispersion index D. The measuring method of the scheme can selectively absorb-CH in polyolefin by selecting the high-temperature gel permeation chromatograph equipped with the infrared detector2and-CH3The group has the advantages of good selectivity, strong anti-interference and high sensitivity; the influence of temperature fluctuation on the infrared detector is less, the base line is stable, the base line and the integral limit are better selected during analysis, the accuracy and the repeatability of results are ensured, and the problem of base line drift caused by the change of refractive index of the differential refraction detector due to the influence of temperature, impurities, additives and the like is avoided. And the infrared detector has no micromolecule discrimination and can accurately detect the micromolecule part.
The high temperature gel permeation chromatograph that this scheme adopted is GPC-IR high temperature gel permeation chromatograph, and GPC-IR high temperature gel permeation chromatograph adopts infrared detector (IR) to replace the refractive index detector (RI) among the traditional high temperature gel permeation chromatograph, and the GPC-IR high temperature gel permeation chromatograph that this application adopted is the chromatograph that Spanish Polymer Char company promoted.
This chromatograph is through chooseing for use full autoinjection, and solid sample directly advances the kind, and subsequent dissolving, filtration, advance kind, chromatogram data acquisition and system wash etc. are accomplished by the instrument is full-automatic, and the solvent consumption is few, greatly reduced the use cost of instrument, practice thrift a large amount of manpowers and material resources, avoided externally carrying out high temperature to the sample simultaneously and dissolved, the full journey needs manually operation's loaded down with trivial details process and the error that manually operation leads to.
The full-automatic sample injector is provided with two temperature control areas, namely a normal temperature area and a high temperature area, nitrogen is added for protection before the sample is heated and dissolved by the solvent, the sample is placed in the normal temperature area, only the sample entering the analysis program enters the high temperature area for heating and dissolving by the solvent, the heating time of each sample to be detected is ensured to be consistent, and the high-temperature oxidative degradation is reduced to the maximum extent. After the samples are dissolved in batches, all the samples are placed in a high-temperature area to wait for analysis, the samples are seriously degraded due to overlong heating time of the samples in subsequent analysis, the degradation degrees of different samples are inconsistent, and experimental errors are reduced.
The present invention will be described in detail with reference to specific examples.
Adopting a GPC-IR high-temperature infrared gel permeameter to test the molecular weight of ENB type EPDM rubber with the grade of 4045M, wherein the specific test steps comprise:
step one, determining a weighing object: narrow distribution PS standard sample and EPDM sample to be detected;
step two, accurately weighing 10-100 mg of molecular weight 102～107Respectively placing the 16 narrow-distribution PS series standard samples in sample bottles, weighing 16mg of EPDM samples to be detected when the PS standard samples with higher molecular weight are less in sample weighing amount, and placing the samples in the sample bottles;
step three, the detection conditions are as follows: setting the temperature at 160 ℃, the solvent amount at 8mL, the sample dissolving time at 60min, wherein the solvent for dissolving the sample is chromatographic pure 1,2, 4-trichlorobenzene containing 0.30g/L BHT; the flowing phase during the test also contains 0.30g/L BHT, which is beneficial to preventing the sample dissolved at high temperature from being oxidized and thermally degraded, the flow rate of the flowing phase during the test is 1.0mL/min, and the sample injection amount is 200 muL; the chromatographic conditions were: three Mixed-B gel permeation chromatographic columns were connected in series.
Step four, implementing sample detection
The autosampler transfers the first sample to a high temperature zone for dissolution at a specified time according to a program set by software; meanwhile, the flow rate of the instrument is gradually increased, the flow rate is stabilized to 1.0mL/min, the pressure and the temperature are stable, sample introduction test is started after the baseline of the instrument is stable, and chromatographic data are collected;
step five, establishing a narrow distribution PS correction curve
Inputting the number average molecular weight and weight average molecular weight standard values of the 16 narrow-distribution PS standard samples in the step two, calculating a one-time or q-time (q is less than or equal to 3) fitting curve of the logarithm lgM of the molecular weight of the standard sample and the retention time t as a correction curve through high-temperature GPC software, and determining a coefficient R of the correction curve2≥0.99；
Step six, data processing
Treating the EPDM sample with the calibration curve determined in step five to obtain the number average molecular weight of the sample
Weight average molecular weight value
And dispersion index D, a graph of test results, see fig. 1. And taking the arithmetic mean value of 2 times of measurement as the final result of the molecular weight and the dispersion index D of the EPDM sample, and reserving three effective digits for the result to obtain the accuracy and precision of the detection experiment.
The molecular weights and distributions of two batches of 4045M ENB EPDM tested in this example and by high temperature differential gel permeation are shown in Table 1. it can be seen from Table 1 that the weight average molecular weights obtained by the two methods are not very different, but the number average molecular weight measured by high temperature infrared GPC is not very different
Significantly lower than the number average molecular weight determined by high temperature differential GPC
The value of the dispersion index D is therefore significantly increased. Therefore, the high-temperature infrared detector can accurately detect the small molecular weight part and can truly reflect the information of the molecular weight and the molecular weight distribution.
TABLE 1 test results of this example and high temperature differential gel permeation method
FIG. 1 is a diagram showing the result of the EPDM test, and it can be seen from FIG. 1 that the chromatogram represented by the curve A is a positive-Gauss distribution curve, the peak pattern is symmetrical, and the EPDM molecular weight and the distribution thereof can be reflected intuitively; the curve B can intuitively obtain the EPDM thousand carbon methyl number or the short chain branch information, so that the difference of the microstructure of the material can be judged, and the performance of the sample can be comprehensively judged and researched. The test result of the scheme is reliable as can be seen from the figure.
It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations or modifications may be made on the basis of the above description, and all embodiments may not be exhaustive, and all obvious variations or modifications may be included within the scope of the present invention.
Claims (9)
1. The method for measuring the molecular weight of the ethylene propylene diene monomer is characterized by comprising the following steps:
(1) weighing a standard sample and a sample to be detected;
(2) testing through a detection instrument, and respectively collecting chromatographic data of a standard sample and chromatographic data of a sample to be detected;
(3) preparing a calibration curve based on chromatographic data of the standard sample;
(4) determining molecular weight information of a sample to be detected based on chromatographic data of the sample to be detected and the correction curve;
the standard samples are narrow-distribution polystyrene molecular weight standard samples with N different molecular weight levels, and N is an integer greater than or equal to 5; the sample to be detected is an ethylene propylene diene monomer sample to be detected.
2. The method for measuring the molecular weight of ethylene propylene diene monomer according to claim 1, wherein the molecular weight distribution of the narrow-distribution polystyrene molecular weight standard sample is 102～107。
3. The method for measuring the molecular weight of the ethylene propylene diene monomer rubber according to claim 1, wherein the standard sample is weighed to be 10-100 mg; the sample weight of the sample to be detected is 10-20 mg.
4. The method for measuring the molecular weight of ethylene propylene diene monomer according to claim 1, wherein the three high temperature resistant gel permeation chromatographic columns are used in series in the chromatographic column of the high temperature gel permeation chromatograph, and the linear range of the molecular weight of the chromatographic column is 102～107Column efficiency N>104Theoretical plate number/m, resolution Rs>1.5。
5. The method for measuring the molecular weight of ethylene propylene diene monomer rubber according to claim 1, wherein in the step (2), the sample dissolution and test temperature set by the high temperature gel permeation chromatograph is 130-170 ℃, the solvent amount of the dissolved sample is 6-10 ml, and the dissolution time is 45-120 min.
6. The method for measuring the molecular weight of ethylene propylene diene monomer rubber according to claim 5, wherein in the step (2), the solvent used for dissolving the sample in the test is chromatographically pure 1,2, 4-trichlorobenzene or chromatographically pure o-dichlorobenzene, and the antioxidant 2, 6-di-tert-butyl-p-cresol (BHT) with the content of 0.10g/L to 0.50g/L is dissolved in the solvent.
7. The method for measuring the molecular weight of ethylene propylene diene monomer according to claim 6, wherein in the step (2), the flow rate of the mobile phase is 0.8mL/min to 1.2mL/min and the sample amount is 100 μ L to 300 μ L.
8. The method for measuring the molecular weight of ethylene propylene diene monomer according to claim 1, wherein the calibration curve is prepared by fitting a curve obtained by fitting the logarithm lgM of the standard value of the number average molecular weight and/or the weight average molecular weight of the narrow-distribution polystyrene molecular weight standard samples with the N different molecular weight levels to one or q times of retention time t to determine the calibration curve, wherein q is less than or equal to 5; determination coefficient R of correction curve2≥0.99。
9. The method for measuring the molecular weight of ethylene-propylene-diene monomer rubber according to claim 1, wherein the molecular weight information includes a number average molecular weight, a weight average molecular weight value, and a dispersion index.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5646224A (en) * | 1995-01-19 | 1997-07-08 | Japan Synthetic Rubber Co., Ltd. | Rubber composition |
| CN104181185A (en) * | 2013-05-27 | 2014-12-03 | 湖北航天化学技术研究所 | Method for determining contents of monomers of ENB type ethylene-propylene-diene monomer rubber |
| CN107148446A (en) * | 2015-01-14 | 2017-09-08 | 埃克森美孚化学专利公司 | Polymer composition and its production method |
| CN110441419A (en) * | 2019-07-31 | 2019-11-12 | 湖北航天化学技术研究所 | A kind of ethylene propylene diene rubber molecular weight determination |
| CN111918920A (en) * | 2018-04-10 | 2020-11-10 | 埃克森美孚化学专利公司 | Thermoplastic vulcanizate composition |
-
2021
- 2021-11-05 CN CN202111305596.2A patent/CN113820433A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5646224A (en) * | 1995-01-19 | 1997-07-08 | Japan Synthetic Rubber Co., Ltd. | Rubber composition |
| CN104181185A (en) * | 2013-05-27 | 2014-12-03 | 湖北航天化学技术研究所 | Method for determining contents of monomers of ENB type ethylene-propylene-diene monomer rubber |
| CN107148446A (en) * | 2015-01-14 | 2017-09-08 | 埃克森美孚化学专利公司 | Polymer composition and its production method |
| CN111918920A (en) * | 2018-04-10 | 2020-11-10 | 埃克森美孚化学专利公司 | Thermoplastic vulcanizate composition |
| CN110441419A (en) * | 2019-07-31 | 2019-11-12 | 湖北航天化学技术研究所 | A kind of ethylene propylene diene rubber molecular weight determination |
Non-Patent Citations (3)
| Title |
|---|
| 嵇培军 等: "高温凝胶色谱表征高分子量聚乙烯" * |
| 谭利敏 等: "激光光散射法测定三元乙丙橡胶相对分子质量及其分布" * |
| 郗向丽 等: ",原子转移自由基法合成乙丙橡胶接枝物中的热聚合研究" * |
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