1、BRITISH STANDARDBS EN 14881:2005Surface active agents Determination of N-(3-dimethylaminopropyl)-alkylamide content in alkylamidopropyl-betaines Gas chromatographic methodThe European Standard EN 14881:2005 has the status of a British StandardICS 71.100.40g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g
2、50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 14881:2005This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2006 BSI 2006IS
3、BN 0 580 46666 3National forewordThis British Standard is the official English language version of EN 14881:2005.The UK participation in its preparation was entrusted to Technical Committee CII/34, Methods of test for surface active agents, which has the responsibility to:A list of organizations rep
4、resented on this committee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”
5、, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard does not of itself confer i
6、mmunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them
7、in the UK.Summary of pagesThis document comprises a front cover, an inside front cover, the EN title page, pages 2 to 12, an inside back cover and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No.
8、Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 14881August 2005ICS 71.100.40English VersionSurface active agents - Determination of N-(3-dimethylaminopropyl)-alkylamide content inalkylamidopropylbetaines - Gas chromatographic methodAgents de surface - Dtermination de la teneur en N-(
9、3-dimthylaminopropyl)-alkylamide dans lesalkylamidopropylbtanes - Mthode par chromatographieen phase gazeuseGrenzflchenaktive Stoffe - Bestimmung des Gehaltes anN-(3-dimethyl-aminopropyl)-alkylamid inAlkylamidopropylbetainen - GaschromatographischesVerfahrenThis European Standard was approved by CEN
10、 on 8 July 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be
11、 obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central S
12、ecretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Po
13、rtugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2005 CEN All rights of exploitation in any form and by any means reservedw
14、orldwide for CEN national Members.Ref. No. EN 14881:2005: EEN 14881:2005 (E) 2 Contents Page Foreword 3 1 Scope .4 2 Normative references .4 3 Principle.4 4 Reagents4 5 Apparatus 5 6 Sampling and preparation of the sample 5 7 Procedure 5 8 Calculation and expression of results.6 9 Precision6 10 Test
15、 report .6 Annex A (informative) N-(3-(dimethylaminopropyl)-undecylamide.7 Annex B (informative) Reference gas chromatogram8 Annex C (informative) Validation method.10 Annex D (informative) Inter-laboratory test results11 Bibliography.12 EN 14881:2005 (E) 3 Foreword This European Standard (EN 14881:
16、2005) has been prepared by Technical Committee CEN/TC 276 “Surface active agents”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2006, and con
17、flicting national standards shall be withdrawn at the latest by February 2006. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia,
18、 Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 14881:2005 (E) 4 1 Scope This European Standard specifies a method for the determina
19、tion of the content of free N-(3-dimethylaminopropyl)-alkylamides (amidoamine) in alkylamidopropylbetaines, expressed in grams per 100 g of product. This method is applicable in the range between 0,02 g and 1,0 g of amidoamine per 100 g of product. 2 Normative references The following referenced doc
20、uments are indispensable for the application of this European Standard. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 3696, Water for analytical laboratory use Specification and t
21、est methods (ISO 3696:1987) ISO 607, Surface active agents and detergents Methods of sample division 3 Principle The method is based on the amidoamine extraction with diethyl ether at alkaline pH and subsequent analysis of the organic extract by GLC-FID. The chromatogram resolves the different amido
22、amines according to their alkyl chain length. The result is calculated from the sum of all the chain homologues. 4 Reagents WARNING: Your attention is drawn to the regulations covering the handling of hazardous substances. Technical organisational and personal protection measures should be observed.
23、 During the analysis, unless otherwise specified, use only reagents of recognized analytical grade that have been checked in advance as not interfering with the analytical results. 4.1 Water, complying with grade 3 as defined in EN ISO 3696. NOTE If the water is purified via ion-exchange resins, ens
24、ure that no cationic or anionic species from the resins cause interference. 4.2 Ethanol 4.3 Diethyl ether 4.4 N-(3-dimethylaminopropyl)-undecylamide (amidoamine-C11), purity 98 % m/m. NOTE The N-(3-dimethylaminopropyl) alkylamide standard preparation and purity determination are given in Annex A. 4.
25、5 Potassium hydroxide, ethanolic solution c (KOH)= 1 mol/l. 4.6 Internal standard solution Weigh in a 50 ml volumetric flask, to the nearest 0,1 mg, approximately 0,2 g of the amidoamine-C11 (4.4). Dissolve and make up to the mark with ethanol (4.2). Keep tightly closed. 4.7 Sodium chloride, aqueous
26、 solution, 30 % m/m. 4.8 Phenolphthalein, solution of 1 % m/V in ethanol. EN 14881:2005 (E) 5 5 Apparatus Ordinary laboratory apparatus and the following. 5.1 Gas chromatograph, with capillary split injector, flame ionisation detector and integrator or computer. 5.2 Fused silica capillary column, co
27、ating with bonded deactivated poly (5 % diphenyl/95 % dimethyl) siloxane, length 30 m, internal diameter 0,25 mm, film thickness 0,50 m (PTA-51). 5.3 Syringe, capacity 1 l. 6 Sampling and preparation of the sample The laboratory sample shall be prepared and stored in accordance with ISO 607. 7 Proce
28、dure 7.1 Calibration Since it is assumed that the response factor of the different homologues is the same no extra calibration is needed (see Annex C). 7.2 Determination Weigh to the nearest 0,1 mg, approximately 3,0 g of sample in a 15 ml vial with snap cap. Add 2 ml of NaCl solution (4.7), and hom
29、ogenise. Add 1 ml of internal standard solution (4.6), measured with a one-mark pipette. Add two drops of the phenolphthalein solution (4.8) and enough potassium hydroxide solution (4.5) to red change and add few extra drops of potassium hydroxide solution. Add 4 ml of diethyl ether (4.3) measured w
30、ith a measuring cylinder. Stopper and shake the tube vigorously for about 1 min. Let stand until the phases separate (usually 2 min will be enough). Analyse the organic phase by injecting 1 l of the organic layer directly into the gas chromatograph (5.1). Set up the gas chromatograph to give results
31、 similar to the reference chromatogram in Figure B.1. 1) PTA-5 is the trade name of product supplied by Supelco (U.S.A). This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of the product named. EN 14881:2005 (E) 6 8 Calculat
32、ion and expression of results The content of total free amidoamine, c, in the sample, expressed in grams per 100 g of the product, is calculated by the equation: isisAmwAmc= (1) where mIS is the mass of the internal standard, in grams, present in 1 millilitre; m is the mass of the test sample, in gr
33、ams; AISis the peak area of the internal standard in the chromatogram of the sample solution; A is the sum of the areas of all the peaks corresponding to alkylamidoamine homologues (except that of the internal standard) in the chromatogram of the sample solution; w is the purity of internal standard
34、 in grams per 100 g (see Annex A). The relative response factor of all the N-(3-dimethylaminopropyl)- alkylamide homologues with respect to the internal standard N-(3-dimethylaminopropyl)- undecylamide is assumed to be 1 (see Annex C). 9 Precision 9.1 Repeatability limit The absolute difference betw
35、een two independent single test results, obtained using the same method on identical test material in the same laboratory by the same operator using the same equipment within a short interval of time, will not exceed the repeatability limit, r, in more than 5 % of the cases. Precision data are given
36、 in Annex D. 9.2 Reproducibility limit The absolute difference between two independent single test results, obtained using the same method on identical test material in different laboratories by different operators using different equipment, will not exceed the reproducibility limit, R, in more than
37、 5 % of the cases. Precision data are given in Annex D. 10 Test report The test report shall include the following information: a) all information necessary for the complete identification of the sample; b) method used (a reference to this European Standard, i.e. EN 14881); c) test results; d) detai
38、ls of any operation not specified in this European Standard or in the standards to which reference is made, and any operations regarded as optional, as well as any incidents like to have affected the results. EN 14881:2005 (E) 7 Annex A (informative) N-(3-dimethylaminopropyl)-undecylamide A.1 Prepar
39、ation of N-(3-dimethylaminopropyl)-undecylamide 250 g (1,34 mol) undecanoic acid of about 98 % purity is weighed together with 1,5 g of 50 % hypophosphorous acid into a 500 ml four-neck round-bottom flask equipped with an immersion thermometer, an addition funnel, a mechanical stirrer, condenser and
40、 nitrogen purge systems. 206 g (2,01 mole) dimethylaminopropylamine (DMAPA) is added drop wise during 30 min at 140 C under N2 atmosphere. Temperature is then raised up to 200 C within 3 h while the water is removed. The reaction is completed at 200 C for an additional 2 h, when the acid value becom
41、es lower than 1 mg KOH/g. The reactor content is cooled down to 180 C and the condenser system removed. Keeping the system at 180 C under a reduced pressure of 2 mm/Hg for an additional 2 h distils off the residual DMAPA. A.2 Determination of purity of N-(3-dimethylaminopropyl)-undecylamide standard
42、 The N-(3-(dimethylaminopropyl)-undecylamide standard purity is determined as follows: 100101,56186100rAVw = (A.1) where w is the concentration of the N-(3-dimethylaminopropyl)-undecylamide (internal standard) in grams per 100 grams; AV is the acid value of the N-(3-dimethylaminopropyl)-undecylamide
43、, in milligrams KOH per gram; r is the relative percentage of alkyl chain C 11 obtained by gas chromatograph. 186 is the molecular weight of the undecanoic acid. NOTE 1 The acid value (AV) corresponds to the determination of free undecanoic acid by potentiometric titration with a potassium hydroxide
44、 standard volumetric solution c (KOH) = 0,1 mol/l in ethanol (see EN ISO 660). NOTE 2 The alkyl chain purity (r) is determined by analysing an ethanolic solution of 5 % (m/V) by gas chromatography following the same conditions specified in 7.2 and calculated by areas normalisation in percentage. EN
45、14881:2005 (E) 8 Annex B (informative) Reference gas chromatogram Key 1 response 2 time Figure B.1 Reference gas chromatogram EN 14881:2005 (E) 9 The following GC conditions have be found to be suitable: Column PTA-52)(30 m, 0,25 mm, film thickness 0,50 m) Carrier gas Helium Column head pressure 48
46、kPa Split 50 ml/min Injection volume 1l Injector temperature 230 C Detector temperature: FID 330 C Temperature programme 220 C (0 min) to 300 C with 5 C/min; 300C (10 min) 2) PTA-5 is the trade name of product supplied by Supelco (U.S.A). This information is given for the convenience of users of thi
47、s European Standard and does not constitute an endorsement by CEN of the product named. EN 14881:2005 (E) 10 Annex C (informative) Validation method C.1 Selectivity All the signals corresponding to alkylamidoamine and the internal standard are perfectly separated. The relative retention factor betwe
48、en the signals of C 11 and C 12 is = 1,2. C.2 Linearity Range studied: 0,02 % to 1,0 % of coconut alkylamidopropylamine. The adjusted regression line of AIS/AC12versus cIS/cC12(within the studied range) fits the linearity requirements specified: Experimental Tolerance Correlation coefficient (r) 0,9
49、99 6 0,98 % Sbrelative (%) 1,134 2,0 % Proportionality test 0,019 0,517 9 includes 0 iISiISccAA = 0150,1 (C.1) Since the slope is quite close to 1, it can be assumed that the relative response factor between all the alkylamidopropylamines is 1. C.3 Precision Fits the established criteria CV CV (Horwitz) where: CV = 5,82 % CV (Horwitz) = 6,28 % Resulting of n = 6 analysis under repeatability conditions. C.4 Recovery The recovery is 100,35 % with a CV (Recovery) of 4,5 % in an alkylamidopropylbetaine with 0,1 % of alkyl
