1、- AECMA PREN*:bO4O 95 = 10123LL 0010184 TL2 AECMA STANDARD NORME AECMA AECMA NORM prEN 6040 Edition PI November 1995 PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - B-1200 BRUXELLES - Tel. (32) 2 775 81 10 - Fax. (32) 2 775 81 11 ICs : Descriptors : ENGLISH VERS
2、ION Aerospace series Non-metallic materials Test method Analysis of thermoset systems by High Performance Liquid Chromatography (HPLC) Srie arospatiale Luft- und Raumfahrt Matriaux non mtalliques Nichtmetallische Werkstoffe Mthode dessai Prfverfahren Analyse von Duromersystemen mittels Analyse des s
3、ystmes thermodurcissables par Chromatographie en phase Liquide Haute Performance (CLHP) Hochleistungs-Flssigkeitschromatographie (HPLC) This “Aerospace Series“ Prestandard has been drawn up under the responsibility of AECMA (The European Association of Aerospace Industries). It is published on green
4、 paper for the needs of AECMA-Members. It has been technically approved by the experts of the concerned Technical Committee following comment by the Member countries. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an extent that interchangeability is
5、 affected, physically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Checking Centre (NPS) and formal agreement of the Official Services of the Member countries it will be submitted as a draft European Standard to CEN (European Commi
6、ttee for Standardization) for formal vote. Nota - Extra cooles can be SUDDlied bv B.N.A.E. - Technooolis 54 - 199, rue Jean-Jacques Rousseau - 921 38 ISSY-LES-MOULINEAUX CEDEX AIBITFG Chairman I Comments should be sent within six months after the date of Dublication to Edition approved for publicati
7、on 1995-12-15 AECMA Gulledelle 94 B-1200 BRUXELLES Mr K. Schneider I I aecma 199, AECMA PREN*b040 95 101231L 0010185 959 Page 2 prEN 6040 : 1995 Contents list 1 2 3 4 5 6 7 a 9 10 Scope Normative references Abbreviations Principle of the method Designation of the method Apparatus Test specimen Proce
8、dure Presentation of the results Test report Page 3 prEN 6040 : 1995 1 Scope This test method defines the procedure to be used for the determination of the composition (resin, curing- agentkatalyst, reaction products, modifier) of the soluble components of thermoset systems with or without reinforce
9、ment in the uncured state using High Performance Liquid Chromatography (HPLC). This method is applicable to : - fibre reinforced matrix systems (such as prepreg) - neat resin systems (such as film adhesives, laminating systems and components such as hardeners and epoxy resins) - sizing systems This
10、standard does not give any directions necessary to meet the health and safety requirements. It is the responsibility of the user of this standard to adopt appropriate health and safety precautions. This standard indicates items and/or subjects, which are marked with an asterisk (*l. These items and/
11、or subjects are typical and they shall be exactly defined in the relevant specification invoking the test. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in t
12、he text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to
13、applies. EN 2331 Aerospace series Textile glass fibre preimpregnates. Test methods for the determination of the resin and fibre content. EN 2559 Aerospace series Carbon fibre preimpregnates. Test method for the determination of the resin and fibre content. I EN 2743 Aerospace series Reinforced Plast
14、ics. Standard procedures for conditioning prior to testing.4 3 Abbreviations HPLC : high performance liquid chromatography istd : internal standard DAD : diode array detector S standard deviation cv coefficient of variation X CH,CN : acetonitrile value with the biggest difference to mean value (Grub
15、bs) I Published as AECMA Prestandard at the date of publication of this standard Page 4 prEN 6040 : 1995 Description Block Analysis of thermoset systems by DMF : dimethylformamide DMSO : dimethyl sulfoxide HNO, : nitric acid MEK : 2 - butanone NMP : N - methylpyrrolidone Identity block EN 6040 4 Pri
16、nciple of the method The HPLC test is in general: - first separating the components of uncured organic polymer matrix systems (the low molecular weight part = prepolymers) - second detecting the soluble components by means of UV-detection expressed in retention times and integrated peak areas An ide
17、ntification - both qualitative and quantitative is obtained by calibration with the individual components, as specified in the relevant specification invoking the test. 5 Designation of the method The designation of the method used shall be drawn up according to the following example 6 Apparatus (se
18、e 1 for itemhubject marked with an *) 6.1 HPLC - equipment The test shall be performed with a liquid chromatograph (HPLC) capable of operating within the limits laid down in the test procedure. 6.2 Column The separation of the components shall be achieved using a steel column filled with reverse pha
19、se material. A pre-column can be used, but is not mandatory. - column dimensions : (4,6 x 200 mm)* - separation material : RP8*, 5 pm* - separation performance shall be comparable to the chromatogram shown in the relevant specification invoking the test including selectivity pattern 6.3 UV - detecto
20、r The detection of the components shall be accomplished by an UV-detector. The UV-detector system shall be capable of working within a range from 200-400 nm. Comparable results can be obtained in general only by a photodiode array detection (DAD), in some special cases exceptions may be possible . A
21、ECMA PREN+b040 95 10123LL OOLOLBB 668 Page 5 prEN 6040 : 1995 6.4 Injection system Preferably the injection shall be made using an automatic injection system to guarantee reproducible injection volumes. 6.5 Calibration The equipment shall be calibrated using the internal standard technique (istd) if
22、 applicable. Otherwise use external standard calibration with three component concentrations in different solutions covering the range of determination. Before starting test work the parties shall demonstrate with some samples that equivalent results can be achieved (reproducibility). An agreement b
23、etween the parties about the calibration procedure parameters is necessary. A master curve with fixed integration marks shall be the base of cornparision. The column life shall be fixed by using the resolution of some distinctive peaks, or the plate number as a performance tool. It is advisable to u
24、se separate columns for different resins. 7 Test specimen (see 1 for item/subject marked with an “1 7.1 Fibre reinforced matrix systems, film-adhesives and neat resin systems Take a sample which will contain approximately 250 mg of neat resin system calculated from the actual fibre or carrier conten
25、t. Extract with a maximum of 250 ml solvent, made up in a volumetric flask at 2OOC. Solvent: CH,CN * HPLC grade containing an internal standard (istd) = 0,2 mg/ml di-n-butyl-phthalate“. Extraction conditions: Ultrasonic bath for 30“ minutes at room temperature* or equivalent operation (shaker) . The
26、 extraction shall be done in a multiple operation to dissolve all low molecular components completely e.g. first step 100 ml followed by a second step 100 ml. Filter the extract first through a wide mesh Teflon filter, then fill up to the required volume of 250 ml in a calibrated volumetric flask. B
27、efore injection filter the part of solution to be used for analysis through a 0,45 or 0,22 pm mesh Teflon filter (HPLC solution). 7.1.1 Determination of actual fibrehesin content Carbon composite : according to EN 2559 Glass composite according to EN 2331 Aramid composite : according to EN 2559 but
28、using HNOJDMSO If an insoluble filler (such as SiO,) is present, it shall be determined separately (after the removal of the fibre) by centrifuging and its mass added to the reinforcement content. 7.1.2 Determination of actual carrierhesin content for adhesives Usual extraction technique: use ultras
29、onic bath and an appropriate solvent such as DMF, DMSO, NMP. Determine the carrier weight after twice flushing with solvents such as acetone or MEK and thorough drying. AECMA PRENxb040 95 = LOL23LL OOLOL89 5T4 Page 6 prEN 6040 : 1995 If an insoluble filler is present, it shall be determined separate
30、ly (after the removal of the carrier) by centrifuging and its mass added to the reinforcement content. Actual resin content : mresin = madhesive - mcarrier Calculate the exact concentration of the HPLC solution (approximately 1 mg/ml, accuracy f 0,5%). 7.2 Conditioning 7.2.1 Conditioning of material
31、 stored at ambient temperature For material stored at ambient temperature, the amount of material required for testing shall be sampled and conditioned in the standard atmosphere defined in EN 2743 for a minimum of 2 h, unless otherwise specified. 7.2.2 Conditioning of material stored below ambient
32、temperature For material stored at temperatures lower than ambient temperature, the material, suitably packed in an airtight bag containing suitable desiccant to prevent moisture pickup, shall be allowed to reach ambient temperature over a period of time according to the mass of the package. The act
33、ual time shall be recorded in the report. When the material has reached ambient temperature, the amount required for testing shall be sampled and conditioned in the standard atmosphere defined in EN 2743 for a minimum of 2 h, unless otherwise specified. 7.2.3 Standard atmosphere for testing The test
34、s shall be carried out at (23 * 2)OC and (50 f 5)% relative humidity (EN 2743 B conditions). 7.2.4 Time interval between conditioning and testing After conditioning, the test shall be carried out within 6 h, unless otherwise specified, the specimen being kept in the standard atmosphere until the tes
35、t is carried out. 8 Procedure (see 1 for itemkubject marked with an *) 8.1 Sample + Injection The following test conditions shall apply: Injection volume Standard = 1 O pl, 5 pI optional (5 pl: it may be necessary to change the concentration to 2 mg/ml) Solvent CHJN + istd Solution concentration : s
36、ample 1 mg/ml* Number of injections : A) Basic analysis (e.g. for material qualification) BI Batch release (if specification values/limits are available) - sample analysis: 6 injections from 2 solutions of different specimens - sample analysis: (1 injection from 2 solutions) AECMA PREN*bYO 95 = LOL2
37、3LL OOLOL90 2Lb Page 7 prEN 6040 : 1995 8.2 Separation parameters Solvents Gradient Separation Flush and re ditionin CH,CN (HPLC gradel H,O (HPLC grade) t.b.d. Time min A %I O 0-5 5 - 25 55 55 55 - 98 Start 25 - 28 98 33 - 35 55 End 28 - 33 9a - 55 - The time for flush and reconditioning of the colu
38、mn can be extended if fast changes are not possible due to equipment restrictions. Flow rate 1,5 mllmin Column temperature : RT * - 8.3 Detection Parameters Calibration of UV-wavelength*: Calibration using the istd shall be performed at its maximum absorption (for di-n-butylphthalate as istd analyse
39、d with DAD this is 224 nm). Check of UV-wavelength setting: The area of istd-peak at 4 nm lower and 4 nm higher wavelength should be smaller than the absorption maximum. General UV-detection: The most suitable wavelength region for the detection of UV-active components is 210-230 nm. A wavelength of
40、 224 nm shall be used for the example described above. The bandwidth shall be set for 4nm*. System specific UV detection* : The wavelengths detected depend on the UV-characteristics of the resin components to be analysed. The specific wavelengths should be selected following these general recommenda
41、tions: - at absorption maximal or minimal (if possible: broad UV-peak) - if no max. or min. is available: at a shoulder - if also no shoulder is available: not at a too high up- or down-slope of the UV-curve 9 Presentation of the results (see 1 for itemhbject marked with an *) 9.1 Check of ISTD The
42、retention time and peak area should correlate with the calibration. 9.2 Qualitative Check By comparing the retention times of the sample with those of pure components (if available). AECMA PRENab040 95 = LO12311 OOLOLSL 152 Page 8 prEN 6040 : 1995 9.3 Quantitative check (see figure 1) Integration of
43、 the peak areas (A,B,C . ) of the main components* For the following statistical calculations on this page x is assigned to A,B,C . ! Calculate corrected individual peak areas (xcorr1 using average peak area of istd :(xCor, = x xiStd / xistd) General rule for acceptance or rejection of results: if c
44、vc 1 % = good results, analysis accepted if cv 2% repeat analysis If more than 1 outlier : repeat analysis Calculation of the actual content in wt % using the calibration Calculation of the peak area ratios“ For the ratio component/istd a correction to standard conditions of concentration (1 mg resi
45、n/ml and 0,2 mg istd/ml CH,CN) is necessary 10 Test report The test report shall refer to this standard and include the following: 1 O. 1 Complete identification of the material tested, including manufacturers name, designation, batch number, etc 10.2 All details about the preparation of the specime
46、ns including description and source of specimen 10.3 Mass of sample, resin content, solution concentration 10.4 Ageing and / or exposure condition prior to the test 10.5 Date of test, facility and identification of individuals performing the test 10.6 Equipment and test parameters used including sep
47、aration and detection parameters 10.7 Chromatogram with retention times and peak areas, (attach 1 copy, which shall be typical for the tested sample) and the mean values of the following test results: - retention time of components (including cv) - average peak area of components (uncorrected and co
48、rrected -using istd if necessary- both - content in wt % (using calibration) - peak area ratios including cv) 1 ) Outlier test by Grubbs: For n = 6 and 95% confidence limit ( i 2s) reject X, if T 1,887 T = (XcOrr Xcorr 1 s 1 AECMA PREN*b040 95 LOL23LL OOLO192 O99 Page 9 prEN 6040 : 1995 10.8 The fol
49、lowing results shall be reported as additional information for qualification tests only: - UV-spectrum of each component - control of peak (purity; comparison of UV characteristics at the beginning, maximum and end of - complete calibration using different concentrations up to the end of the linear range - if pure calibration standards are not available, check the linear range using different the peak) concentrations of the complete resin system 10.9 Any incident which may have affected the results and any deviation from this standard AECMA PREN86040
