1、BRITISH STANDARDBS EN ISO 3251:2008Paints, varnishes and plastics Determination of non-volatile-matter contentICS 83.080.01; 87.040; 87.060.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g
2、60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 3251:2008This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 March 2008 BSI 2008ISBN 978 0 580 57647 8National forewordThis British Standard is the UK implementation of EN ISO 3251:2008. It s
3、upersedes BS EN ISO 3251:2003 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee STI/3, Paints, media and related products.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport
4、to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations. Amendments/corrigenda issued since publicationDate CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO
5、3251February 2008ICS 83.080.01; 87.040; 87.060.20 Supersedes EN ISO 3251:2003 English VersionPaints, varnishes and plastics - Determination of non-volatile-matter content (ISO 3251:2008)Peintures, vernis et plastiques - Dtermination de lextraitsec (ISO 3251:2008)Beschichtungsstoffe und Kunststoffe -
6、 Bestimmung desGehaltes an nichtflchtigen Anteilen (ISO 3251:2008)This European Standard was approved by CEN on 7 February 2008.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
7、without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other langua
8、ge made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,Fr
9、ance, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR N
10、ORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 3251:2008: EForeword This document (EN ISO 3251:2008) has been prepared by Technical Committee ISO/TC 35 “Paints an
11、d varnishes“ in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” the secretariat of which is held by DIN. 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 August 2008, and c
12、onflicting national standards shall be withdrawn at the latest by August 2008. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This do
13、cument supersedes EN ISO 3251:2003. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece
14、, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 3251:2008 has been approved by CEN as a EN ISO 3251:2008 without any mod
15、ification. BS EN ISO 3251:2008Reference numberISO 3251:2008(E)INTERNATIONAL STANDARD ISO3251Fourth edition2008-02-15Paints, varnishes and plastics Determination of non-volatile-matter content Peintures, vernis et plastiques Dtermination de lextrait sec BS EN ISO 3251:2008ii iiiContents Page Foreword
16、 iv 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 2 4 Apparatus 2 5 Sampling 3 6 Procedure 3 7 Supplementary test conditions . 4 8 Expression of results . 4 9 Precision 5 10 Test report . 5 Annex A (informative) Commonly used test parameters 6 Bibliography . 7 BS EN ISO 3251:2008iv
17、 Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a
18、technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matter
19、s of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulat
20、ed to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible
21、 for identifying any or all such patent rights. ISO 3251 was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee SC 10, Test methods for binders for paints and varnishes, in collaboration with Technical Committee CEN/TC 139, Paints and varnishes. This fourth edition cancels
22、 and replaces the third edition (ISO 3251:2003), which has been technically revised. The main changes are as follows: a) The heating time, heating temperature and test-portion mass have to be agreed in each case. The tables giving values of these parameters have therefore been moved to an informativ
23、e annex where they are intended to serve as proposals. Values suitable for reactive systems such as car refinish paints have been added. b) The precision data have been corrected. BS EN ISO 3251:20081Paints, varnishes and plastics Determination of non-volatile-matter content 1 Scope This Internation
24、al Standard specifies a method for determining the non-volatile-matter content by mass of paints, varnishes, binders for paints and varnishes, polymer dispersions and condensation resins such as phenolic resins (resols, novolak solutions, etc.). The method is also applicable to formulated dispersion
25、s containing fillers, pigments and other auxiliaries (e.g. thickeners and film-forming agents). For the method to be usable for unplasticized polymer dispersions and rubber latices, the non-volatile residue (which consists essentially of the polymeric material and of small quantities of auxiliaries
26、such as emulsifiers, protective colloids, stabilizers, solvents added as film-forming agents and especially for rubber latex concentrate preserving agents) has to be chemically stable under the test conditions. For plasticized samples, the residue, by definition, normally includes the plasticizer. N
27、OTE 1 The non-volatile-matter content of a product is not an absolute quantity but depends upon the temperature and period of heating used for the determination. Consequently, when using this method, only relative and not true values for non-volatile-matter content are obtained owing to solvent rete
28、ntion, thermal decomposition and evaporation of low molecular mass constituents. The method is therefore primarily intended for testing different batches of the same type of product. NOTE 2 This method is suitable for synthetic rubber latices provided heating for a specific period of time is conside
29、red appropriate (ISO 124 specifies heating until the loss in mass of a 2 g test portion following successive periods of heating is less than 0,5 mg). NOTE 3 In-house methods for determining non-volatile matter often include drying with infrared or microwave radiation. Standardization of such methods
30、 is not possible, since they are not generally applicable. Some polymer compositions tend to decompose during such treatment and therefore give incorrect results. ISO 3233 and ISO 23811 specify methods for determining the volume of non-volatile matter in paints, varnishes and related products. 2 Nor
31、mative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 123, Rubber latex Sampling
32、ISO 124, Latex, rubber Determination of total solids content ISO 1513, Paints and varnishes Examination and preparation of samples for testing ISO 2431, Paints and varnishes Determination of flow time by use of flow cups ISO 15528, Paints, varnishes and raw materials for paints and varnishes Samplin
33、g BS EN ISO 3251:20082 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 non-volatile matter NV residue by mass obtained by evaporation under specified conditions ISO 4618:2006 4 Apparatus Ordinary laboratory apparatus, together with the follow
34、ing: 4.1 For paints, varnishes, binders for paints and varnishes and polymer dispersions: Flat-bottomed dish, of metal or glass, inner diameter of base (75 5) mm, height of rim at least 5 mm. Dishes having different diameters may be used by agreement between the interested parties. The agreed dish d
35、iameter shall be adhered to within 5 %. NOTE 1 For rubber latices, lipless dishes with covers are recommended. NOTE 2 For very viscous polymer dispersions or latices, it is recommended that aluminium foils are used which are about 0,1 mm thick, cut into rectangles of about (70 10) mm (120 10) mm tha
36、t can be folded in half, thus allowing the viscous liquid to be spread by gently squeezing the halves together. 4.2 For liquid crosslinking resins (phenolic resins): Flat-bottomed dish, of metal or glass, inner diameter of base (75 1) mm, height of rim at least 5 mm, for use with a test portion of 3
37、 g. Dishes of different diameters may be used provided the mass of the test portion m, in grams, is calculated from the following equation in order to ensure comparable film thicknesses: 2375dm=(1) where d is the diameter, in millimetres, of the dish base; 3 is the nominal mass of the test portion (
38、3 g); 75 is the nominal diameter of the dish (75 mm). 4.3 Air oven, designed to carry out the test in safe conditions, and capable of being controlled at the specified or agreed temperature (see Clause 7) to within 2 C (for temperatures up to 150 C) or 3,5 C (for temperatures above 150 C and up to 2
39、00 C). The oven shall be fitted with forced-ventilation equipment, except in the case of phenolic resins when an oven with natural convection with a perforated metal shelf placed at one-third of the height of the oven may be used. WARNING To protect against explosion or fire, products containing fla
40、mmable volatile substances should be handled with care. National regulations should be followed. BS EN ISO 3251:20083For certain applications, drying in a vacuum may be preferable. In such cases, the conditions shall be agreed on or the method specified in ISO 124 shall be used. For referee tests, o
41、vens of equivalent construction shall be used by all parties. 4.4 Analytical balance, capable of weighing to an accuracy of 0,000 1 g. 4.5 Desiccator, containing a suitable desiccant, for example dried silica gel impregnated with cobalt chloride. 5 Sampling Take a representative sample of paints, va
42、rnishes and binders for paints and varnishes, as described in ISO 15528. Take a representative sample of polymer dispersions and rubber latices, as described in ISO 123. Examine and prepare samples of paints and varnishes for testing, as described in ISO 1513. 6 Procedure Carry out the determination
43、 in duplicate. Degrease and clean a dish (4.1 or 4.2). For better precision, it is recommended that the dish is dried in the oven (4.3) at the specified or agreed temperature for the specified or agreed period (see Clause 7) and stored in the desiccator (4.5) until used. Determine the mass of the cl
44、ean, dry dish (m0) to the nearest 1 mg. Weigh a test portion (see Clause 7), to the nearest 1 mg, into the dish (m1) and distribute it evenly. In the case of products that are highly viscous (viscosity W 500 mPas at a shear rate of 100 s1or flow time t W 74 s measured with a 6 mm flow cup in accorda
45、nce with ISO 2431) or that form skins, distribute the test portion uniformly with a tared metal wire (for example a bent, uncoated paper-clip), if necessary after addition of 2 ml of a suitable solvent. Condensation resins as used for paints and varnishes and other common applications (for example a
46、brasives, friction linings, foundry binders and moulding materials) require higher test-portion masses since materials used for these applications need to be tested in thicker layers so that the monomers of the condensation resins can react during crosslinking. For comparative tests, the thickness o
47、f the layer of test portion in the dish shall be constant. Therefore the diameter of the dishes shall be (75 1) mm or the formula given in 4.2 shall be used. NOTE 1 The non-volatile-matter content of a test portion is influenced greatly by how well and for how long the test portion is distributed in
48、 the dish. If a test portion is poorly distributed, e.g. because of high viscosity, the apparent non-volatile-matter content will be higher. For better precision when testing paints, varnishes and binders for paints and varnishes, it is recommended that 2 ml of a suitable highly volatile solvent is
49、always added. It is also recommended that the dish is covered during the weighing procedure. In the case of highly volatile products, it is recommended that a portion of the thoroughly mixed sample is placed in a stoppered bottle or, alternatively, in a weighing pipette or a 10 ml syringe without a needle. From this, the test portion is weighed by difference, to the nearest 1 mg, into the dish and distributed evenly over the bottom of the dish. If solvent is added, it is recommended that the dish with the test porti
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