1、CU I i a 8 a F a w Approved by COMITE DE NORMALISATION Of A.ECJ4.A. 1982-09-15 -J w a 9 w - The equivalent versions in French and German languages can be supplied by B.N.A.E., 8, rue Moreau-Vauthier 92100 BOULOGNE-BILLANCOURT - FRANCE. w w CI w 2 2 w u E AECMA-PREN233143 1012311 0002929 4 I _ _ A.E.
2、C.M.A. STANDARD NORME A.E.C.M.A. A.E.C.M.A. NORM prE N2331 Edition 1 February 1983 ENGLISH VERSION TEST METHODS FOR THE DETERMINATION OF THE RESIN CONTENT OF WOVEN TEXTILE GLASS FIBRE FABRIC PREIMPREGNATE AEROSPACE SERIES METHODES DESSAI POUR LA DETERMINATION LUFT- UND RAUMFAHRT DE LA TENEUR EN RESI
3、NE PRFVERFAHREN ZUR BESTIMMUNG DES TISSUS DE VERRE TEXTILE PREIMPREGNES SERIE AEROSPATIALE DES HARZANTEILS VON VORIMPRGNI ERTENI G LASFI LAMENTGEWEBE This industrial standard for the aerospace sector has been drawn up under the responsibility of AECMA (Association Europenne des Constructeurs de Matr
4、iel Arospatial). It is published on yellow paper in three equivalent versions (English, French, German. It will be submitted to CEN (European Committee for Standardization) as a draft European Standard. . I? AECMA PREN2331 d3.,9 LOL23LL 0002730 O W - prEN2331 Page 2 CONTENTS 1 2 3 4 5 6 7 8 9 10 11
5、SCOPE FIELD OF APPLICATION REFERENCES DEFINITIONS PRINCIPLE OF THE METHOD APPARATUS STANDARD ATMOSPHERE FOR CONDITIONING AND TESTING SAMPLING PROCEDURE CALCULATION AND EXPRESSION OF RESULTS TEST REPORT I * e O 1. - AECMA PREN2331 83 LOL23LL 0002731 2 = prEN2331 Page 3 A.E.C.M.A. STANDARD prEN2331 TE
6、ST METHODS FOR THE DETERMINATION OF THE RESIN CONTENT OF WOVEN TEXTILE GLASS FIBRE FABRIC PREIMPREGNATE SCOPE This standard specifies, for woven textile glass fibre fabric preimpregnate for aerospace use, methods for determining the resin content and the insolubility factor of the resin by calcinati
7、on and solvent extraction. FIELD OF APPLICATION 2.1 Calcination method This method had to be used if the material to be tested contains only glass and a resin which is completely combustible. The resin content is equal to the loss on igni ti on. 2.2 Solvent extraction method This method applies to p
8、roducts which contain fillers that lose mass at a temperature equal to or below 600OC. The resin content is equal to the loss on solvent ex tract i on. NOTE : By application of the methods defined in 2.1 and 2.2 the insolubility factor can be calculated. REFERENCES EN2330, Test method for the determ
9、ination of the percentage of volatile matter in woven textile glass fibre fabric preimpregnate EN62 , Glass reinforced plastics - Standard atmospheres for conditioning and testing. DEFINITIONS A woven textile glass fibre fabric preimpregnate with a thermosetting resin is a material that can be purch
10、ased in the form of a synthetic resin impregnated woven textile glass fibre fabric and used for the manufacture of moulded components (The term preimpregnate is often abbreviated to prepreg). AECMA PREN2331 83 = LO12311 0002732 4 W prEN2331 Page 4 5 PRINCIPLE OF THE METHOD 5.1 Calcination method Ign
11、ition of weighed test specimens at a temperature of 625OC to constant mass. 5.2 Solvent extraction method Extraction of resin from weighed specimens with solvent to constant mass. 6 APPARATUS 6.1 Calcination method 6.1.1 Laboratory burner of the Meker type or similar. 6.1.2 Container made of an appr
12、opriate material and of suitable dimensions (a porcelain or platinium crucible or porcelain boat may be used). 6.1.3 Electric muffle furnace, capable of maintaining a temperature of 625 4 20OC. 6.1.4 Desiccator containing a suitable drying agent (for example : silica gel, calcium chloride, phosphoru
13、s pentoxide). 6.1.5 Balance with an accuracy of 0,l mg. 6.2 Solvent extraction method 6.2.1 Single thickness extraction thimble, nominal diameter 20 to 22 mm, nominal length 60 to 80 mm. 6.2.2 Electric oven capable of maintaining a temperature of 105 ,+ 5OC. 6.2.3 A suitable extraction apparatus of
14、the Soxhlet type, comprising a condenser, siphon tube and flask and provided with an electric heating mantle. 6.2.4 Vacuum desiccator. 6.2.5 Balance with an accuracy of 0,l mg. 6.2.6 Methyl ethyl ketone (MEK), analytical grade, or other sui- table solvent, as agreed between purchaser and supplier. 7
15、- - I 8 I 1 AECMA PREN2331 83 10123Ll 0002733 b 1 prEN2331 Page 5 7 STANDARD ATMOSPHERE FOR CONDITIONING AND TESTING 7.1 Conditioning 7.1.1 Material stored at ambient temperature- Unless otherwise specified, the necessary amount of material (see clause 8) shall be sampled and conditioned in the stan
16、dard testing atmosphere (see clause 7.2.1) for a minimum of 2 h. 7.1.2 Material stored below ambient temperature The material, suitably packed in an airtight and solvent resistant bag to prevent moisture pick-up, shall be allowed to reach ambient temperature over a period of time according to the ma
17、ss of the package. This time shall not be less than 8 h and the actual time shall be recorded in the report. When the material has reached the ambient temperature, the necessary amount (see clause 8) shall be sampled and conditioned in the standard testing atmosphere, for a minimum of 2 h, unless ot
18、herwise specified. 7.2 Testing 7.2.1 Standard atmosphere for testing The standard atmosphere shall be in accordance with standard EN62 that is to say that the tests shall be carried out at 23 -+ 2OC and (50 + 5) % relative humidity. Time interval between conditioning and testing - 7.2.2 After condit
19、ioning, the test shall be carried out within 6 h, unless otherwise specified, the specimen being kept in the standard atmosphere until the test is carried out. 8 SAMPLING 8.1 Test specimen The specimen shall have a length of 100 i 1 mm and a width of 100 ,+ 1 mm. Other dimensions of the test specime
20、n may be used subject to agreement between the purchaser and the supplier, but having a surface area of 100 cm2 with an accu- racy of 1: 2%. AECIA PREN2331 83 m 1012311 0002734 8 U prEN2331 Page 6 5.2 Number and distribution of test specimens Five test specimens for each method shall be used. These
21、shall be evenly distributed over the width and cut from the sample diagonally (45) either across the width or along an axis inclined at an angle as close as possible to the weft direction. The specimens shall not be closer than 50 mm to the edges and selvedges (see figures 1 and 2). Dimensions in mi
22、llimetres FIGURE 1 - Example of diagonal positioning of test specimens on woven textile glass fabric sample across the width FIGURE 2 - Dimensions in millimetres I I I I A P I. 50 min. Warp yarns direction - 50 min. I 50 min. 4 Width of woven textile dass fabric Example of diagonal positioning of te
23、st specimens.on woven textile glass fabric sample along an axis inclined 01 -9 wile as close as possible to the weft direction - =-, e a O AECMA PREN2331 83 10123LL 0002735p T prEN2331 Page 7 9 PROCEDURE 9.1 Calcination method 9.1.1 Preparation of container Before commencing each series of tests, a
24、test with the empty container (see clause 6.1.2) shall be performed, by heating in the muffle furnace (see clause 6.1.3) to verify that the mass is constant to 1 mg. Otherwise, repeat this blank test until constant mass is achieved. NOTE : The weighing of the container shall be performed. after the
25、container has been cooled to ambient temperature in a desiccator (see clacse 6.1.4). 9.1.2 Weighing and ignition of test specimens For each test specimen, carry out the following sequence of operations : 9.1.2.1 Weigh the container (see clause 9.1.2) to the nearest mg, prepared as indicated in claus
26、e 9.1.1 Place the test specimen, cut into pieces of convenient slze in the container, care being taken that the container with the test specimen in a flame until the contents ignite. Maintain such a temperature that the specimen burns at a moderate rate until only ash and carbon remain when the burn
27、ing ceases. 9.1.2.2 Heat the container and residue in the muffle furnace (see clause 6.1.31, to the temperature of 625 k 20C and maintain this until all carbon has disappeared. 9.1.2.3 Cool the container and the residue in a desiccator (see clacse 6.1.4) to ambient temperature and weigh to the neare
28、st mg. 9.1.2.4 Repeat the operations specified in 9.1.2.2 and 9.1.2.3 until the difference in mass on two successive weighings is less than 2 mg. 9.2 Solvent extraction method 9.2.1 Preparation of extraction thimble Dry the extraction thimble (see clause 6.2.1) in an oven, (see clause 6.2.2), at 105
29、 L 5OC for 2 h, cool to ambient temperature in a desiccator and weigh, to verify that the mass is constant to 1 mg. Otherwise, repeat this blank test until constant mass is achieved. 9.2.2 Weighing of specimen anci solvent extraction of resin For each test specimen carry out the following sequence o
30、f operations : I AECMA PREN2331 83 m 1012311 000293b L W 1 prEN2331 Page 8 9.2.2.1 Weigh the thimble (see clause 6.2.1) to the nearest mg prepared as indicated in 9.2.1. Place the test specimen, cut into pieces of convenient size, in the thimble,.care being taken that no fragments are lost and weigh
31、 to the nearest mg. Place the thimble and its contents in the siphon tube of the extraction apparatus (see clause 6.2.3). Fit the condenser, siphon tube and flask together and add a suitable quantity of Soxhlet of methyl ethyl ketone (MEK) (see clause 6.2.6). 9.2.2.2 Regulate the heating of the mant
32、le so that the siphoning rate is compatible with the total extraction of the resin during and supplier. Remove the thimble and contents, dry in a vacuum desiccator (see clause 6.2) and weigh to the nearest mg. n +10 min, or for an other period, as agreed between purchaser 6o o 9.2.2.3 9.2.2.4 Repeat
33、 the drying specified in 9.2.2.3 until the difference in mass on two successive weighings is less than 2 mg. 10 CALCULATION AND EXPRESSION OF RESULTS 10.1 Calcination method The resin content for each test specimen, expressed as a percentage of the original mass, is calculated from the formula : whe
34、re : Pi = the resin content expressed as a percentage of the original mass, ml = the mass of the container, in g, m2 = the initial total mass of the container plus the specimen, in g, m3 = the final total mass, after ignition, of the container and the V = the percentage of volatile matter determined
35、 by EN2330. residue, in g, 10.2 Solvent extraction method The resin content for each test specimen, expressed as a percentage of the original mass, is calculated from the formula : mg - P2 = 190 ( mg - “) - v where : p2 = the resin content expressed as a percentage of the original mass, m4 = the mas
36、s of the thimble, in g, m5 = the initial total mass of the thimble plus the specimen, in g, m6 = the final total mass, after solvent extraction, of the thimble V = the percentage of volatile matter determined by EN2330. and the residue, in g, -Y- -!- AECMA PREN2331 83 1UL2-311l1 0002737 3 a prEN2331
37、 Page 3 10.3 Insolubility factor of the resin Calculate the arithmetic mean P4 and P5 of the values obtained for P1 and P2. The insolubility factor can be calculated from the formula : where : P3 is the insolubility factor of the resin expressed as a percentage of the original mass, P4 is the arithm
38、etic mean of the values P1 or the resin content determined by the calcination method, P5 is the arithmetic mean of the values Pz for the resin content determined by the solvent extraction method. 11 TEST REPORT The test report shall include the following information : 11.1 Number of this standard, 1
39、1.2 Reference to the type of preimpregnate, with complete description, 11.3 Dimensions of specimens if these differ from clause 8.1, 1l.U Number of test specimens used, 11.5 The volume of the Soxhlet apparatus, the solvent used and the siphoning rate or frequency, in case the solvent method has been
40、 used, 11.6 The actual time used for conditioning to standard atmosphere. 11.7 The individual values, 11.8 The arithmekic mean value of the resin content, expressed as a percentage of the original mass, determined by the calcination method and/or the solvent extraction method and, where appropriate, the calculated insolubility factor, expressed as a percentage of the original mass, 11.9 Observations on any circumstances liable to influence the results. ./- -y
