1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-20256-9 SANS 3251:2007Edition 2ISO 3251:2003Edition 3SOUTH AFRICAN NATIONAL STANDARD Paints, varnishes and plastics Determination of non-v
4、olatile-matter content This national standard is the identical implementation of ISO 3251:2003 and is adopted with the permission of the International Organization for Standardization. Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 f
5、ax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 3251:2007 Edition 2 ISO 3251:2003 Edition 3 Table of changes Change No. Date Scope National foreword This South African standard was approved by National Committee StanSA SC 5140.11I, Paints and varnishes Test m
6、ethods, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in December 2007. This SANS document supersedes SABS ISO 3251:1993 (first edition). Reference numberISO 3251:2003(E)ISO 2003INTERNATIONAL STANDARD ISO3251
7、Third edition2003-02-15Paints, varnishes and plastics Determination of non-volatile-matter content Peintures, vernis et plastiques Dtermination de lextrait sec SANS 3251:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .ISO 3251:2003(E) PDF
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9、ties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative
10、 to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO 2003
11、All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the countr
12、y of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2003 All rights reservedSANS 3251:2007This s tandard may only be used and printed by approved subscription a
13、nd freemailing clients of the SABS .ISO 3251:2003(E) ISO 2003 All rights reserved iiiContents Page Foreword 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 5 9 Precision 6 10 Tes
14、t report 6 SANS 3251:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .ISO 3251:2003(E) iv ISO 2003 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
15、(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 technical committee has been established has the right to be represented on that committee. International organizations, g
16、overnmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/I
17、EC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the mem
18、ber 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 for identifying any or all such patent rights. ISO 3251 was prepared by Technical Committee ISO/TC 35, Paints and varnish
19、es, Subcommittee SC 10, Test methods for binders for paints and varnishes, in collaboration with ISO/TC 45, Rubber and rubber products, as well as ISO/TC 61, Plastics, Subcommittee SC 9, Thermoplastic materials, and Subcommittee SC 12, Thermosetting materials. This third edition cancels and replaces
20、 the second edition (ISO 3251:1993) and, in addition, ISO 1625:1998 and ISO 8618:1995. During the revision and combination of these International Standards, the procedures used for determining the non-volatile-matter content of polymer dispersions and liquid phenolic resins were integrated into the
21、procedure used in ISO 3251. The period of heating, temperature and test-portion mass used for the various types of product were not changed. SANS 3251:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .INTERNATIONAL STANDARD ISO 3251:2003(E)
22、 ISO 2003 All rights reserved 1Paints, varnishes and plastics Determination of non-volatile-matter content 1 Scope This International Standard specifies a method for determining the non-volatile-matter content by mass of paints, varnishes, binders for paints and varnishes, polymer dispersions and co
23、ndensation resins such as phenolic resins (resols, novolak solutions, etc.). The method is also applicable to formulated dispersions containing fillers, pigments and other auxiliaries (e.g. thickeners and film-forming agents). For the method to be usable for unplasticized polymer dispersions and rub
24、ber latices, the non-volatile residue (which consists essentially of the polymeric material and of small quantities of auxiliaries such as emulsifiers, protective colloids, stabilizers, solvents added as film-forming agents and especially for rubber latex concentrate preserving agents) has to be che
25、mically stable under the test conditions. For plasticized samples, the residue, by definition, normally includes the plasticizer. NOTE 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. Consequ
26、ently, when using this method, only relative and not true values of the non-volatile-matter content are obtained owing to solvent retention, thermal decomposition and evaporation of low-molecular-mass constituents. The method is therefore primarily intended for testing different batches of the same
27、type of product. NOTE 2 This method is suitable for synthetic rubber latices provided heating for a specific period of time is considered 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
28、methods for determining non-volatile matter often include drying with infrared or microwave radiation. Standardization of such methods is not possible, since they are not generally applicable. Some polymer compositions tend to decompose during such treatment and therefore give incorrect results. ISO
29、 3233:1998, Paints and varnishes Determination of percentage volume of non-volatile matter by measuring the density of a dried coating, specifies a method for determining the volume of non-volatile matter in paints, varnishes and related products. 2 Normative references The following referenced docu
30、ments 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 ISO 124, Latex, rubber Determination of total s
31、olids 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 Sampling SANS 3251:2007This s tandard may only be used
32、 and printed by approved subscription and freemailing clients of the SABS .ISO 3251:2003(E) 2 ISO 2003 All rights reserved3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 non-volatile matter the percentage residue by mass obtained by evaporati
33、on under specified conditions 4 Apparatus Ordinary laboratory apparatus, together with the following: 4.1 For paints, varnishes, binders for paints and varnishes and polymer dispersions: Flat-bottomed dish, of metal or glass, (75 5) mm in diameter, height of rim at least 5 mm. Dishes having differen
34、t diameters may be used by agreement between the interested parties. The agreed dish diameter shall be adhered to 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 be us
35、ed which are about 0,1 mm thick, cut into rectangles of about (70 10) mm (120 10) mm that 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 d
36、iameter of base (75 1) mm, height of rim at least 5 mm. Dishes of different diameters may be used provided the mass of the test portion m, in grams, is calculated from the following equation: 2375dm=(1) where d is the diameter, in millimetres, of the dish base; 3 is the nominal mass of the test port
37、ion (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 maintaining the specified or agreed temperature (see Clause 7) to within 2 C (for temperatures up to 150 C) or to within 3,5 C (for temperatures above 150 C and
38、up to 200 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 contain
39、ing flammable volatile substances should be handled with care. National regulations should be followed. For 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, ovens of equiv
40、alent construction shall be used by all parties. 4.4 Analytical balance, capable of weighing to an accuracy of 0,1 mg. SANS 3251:2007This s tandard may only be used and printed by approved subscription and freemailing clients of the SABS .ISO 3251:2003(E) ISO 2003 All rights reserved 34.5 Desiccator
41、, containing a suitable desiccant, for example dried silica gel impregnated with cobalt chloride. 5 Sampling Take a representative sample of paints, varnishes and binders for paints and varnishes, as described in ISO 15528. Take a representative sample of polymer dispersions and rubber latices, as d
42、escribed in ISO 123. Examine and prepare samples of paints and varnishes for testing, as described in ISO 1513. 6 Procedure Carry out the determination in duplicate. Degrease and clean a dish (4.1 or 4.2). For better precision it is recommended that the dish be dried in the oven (4.3) at the specifi
43、ed 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 clean, 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
44、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 accordance 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 nec
45、essary after addition of 2 ml of a suitable solvent. Condensation resins as used for paints and varnishes and other common applications (for example abrasives, friction linings, foundry binders, moulding materials) require higher test-portion masses since materials used for these applications need t
46、o be tested in thicker layers so that the monomers of the condensation resins can react during crosslinking. For comparative tests, the thickness of 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
47、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 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
48、precision when testing paints, varnishes and binders for paints and varnishes, it is recommended that 2 ml of a suitable highly volatile solvent is 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
49、that a portion of the thoroughly mixed sample be 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 portion is allowed to stand at room temperature for 10 min to 15 min. Aqueous systems such as polymer dispersions and rubber latices splas
