1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Methods of testICS 83.040.20Rubber compounding ingredients Magnesium oxide BRITISH STANDARDBS ISO 2
2、1869:2006BS ISO 21869:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 April 2006 BSI 2006ISBN 0 580 48110 7Cross-referencesThe British Standards which implement international publications referred to in this document may be found in th
3、e BSI Catalogue under the section entitled “International Standards Correspondence Index”, 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 f
4、or its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations.Summary of pagesThis document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 14, an inside back cover and a back cover
5、.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA list of organizations represented on this committee can be obtained on request to its secretary. present to the responsible international/Europe
6、an committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.National forewordThis British Standard reproduces verbatim ISO 21869:2006 and implements it as the UK natio
7、nal standard.The UK participation in its preparation was entrusted to Technical Committee PRI/23, Test methods for rubber and non-black compounding ingredients, which has the responsibility to: aid enquirers to understand the text;Reference numberISO 21869:2006(E)INTERNATIONAL STANDARD ISO21869FIrst
8、 edition2006-04-01Rubber compounding ingredients Magnesium oxide Methods of test Ingrdients de mlange du caoutchouc Oxyde de magnsium Mthodes dessai BS ISO 21869:2006ii iiiContents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Sampling 1 4 Moisture, magnesium hydroxide and
9、 magnesium carbonate content 1 5 Determination of the specific surface area 5 6 Determination of the copper and manganese content . 5 7 Determination of the sieve residue. 10 8 Determination of the chloride and sulfate contents 11 9 Test report . 13 Annex A (informative) Typical values of properties
10、 of magnesium oxides used as rubber compounding ingredients 14 BS ISO 21869:2006iv 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 throu
11、gh 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, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collabora
12、tes 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/IEC Directives, Part 2. The main task of technical committees is to prepare International Standar
13、ds. 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 member bodies casting a vote. Attention is drawn to the possibility that some of the elements of th
14、is document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 21869 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 3, Raw materials (including latex) for use in the rubber industry. BS
15、 ISO 21869:2006vIntroduction Magnesium oxide is used in the rubber industry as a stabilizer, as an agent for modifying the vulcanization process and to enhance the heat resistance of rubber articles. The performance of magnesium oxide in these roles is dependent on its particle size, surface propert
16、ies and purity. This International Standard specifies the methods used to determine these properties. It is based on NF T 45-006 (France). BS ISO 21869:2006blank1Rubber compounding ingredients Magnesium oxide Methods of test WARNING Persons using this International Standard should be familiar with n
17、ormal laboratory practice. This standard does not purport to address all the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1 Scope This Inte
18、rnational Standard specifies the test methods to be used for magnesium oxide intended for use in the rubber industry as a stabilizer and vulcanizing agent. The choice of the properties to be determined and the values required shall be agreed between the interested parties. 2 Normative references The
19、 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 565, Test sieves Metal wire cloth, perforated me
20、tal plate and electroformed sheet Nominal sizes of openings ISO 3819, Laboratory glassware Beakers ISO 4652-1, Rubber compounding ingredients Carbon black Determination of specific surface area by nitrogen adsorption methods Part 1: Single-point procedures ISO 15528, Paints, varnishes and raw materi
21、als for paints and varnishes Sampling ISO 18852, Rubber compounding ingredients Determination of multipoint nitrogen surface area (NSA) and statistical thickness surface area (STSA) 3 Sampling Sampling shall be carried out in accordance with ISO 15528. 4 Moisture, magnesium hydroxide and magnesium c
22、arbonate content Two methods are included: thermogravimetry and oven heating. BS ISO 21869:20062 4.1 Thermogravimetry 4.1.1 Procedure The tests are performed on a thermogravimetric analyser capable of controlling temperature at 105 C 10 C, 390 C 20 C and 750 C 50 C. The tests are performed in either
23、 an air or a nitrogen flow of 100 cm3/min 20 cm3/min. The temperature increase rate should be between 20 C/min and 40 C/min while the temperature sweep shall go from ambient to 800 C. 4.1.2 Expression of results 4.1.2.1 Moisture content (mass loss from ambient to 105 C) Moisture content (%) = 100 (m
24、1 m2)/m1where m1is the mass of the test portion, in grams; m2is the mass after heating to within the 95 C to 115 C temperature range, in grams. 4.1.2.2 Magnesium hydroxide content (mass loss from 105 C to 390 C) Mg(OH)2content (%) = 100 3,2(m2 m3)/m1where m1and m2are as defined in 4.1.2.1; m3is the
25、mass after heating to within the 370 C to 410 C temperature range, in grams; 3,2 is the ratio between 58, the molecular mass of magnesium hydroxide, and 18, the molecular mass of water, calculated on the basis of the following reaction: Mg(OH)2 MgO + H2O 4.1.2.3 Magnesium carbonate content (mass los
26、s from 390 C to 750 C) MgCO3content (%) = 100 1,9(m3 m4)/m1where m1is as defined in 4.1.2.1; m3is as defined in 4.1.2.2; m4is the mass after heating to above 700 C, in grams; 1,9 is the ratio between 84, the molecular mass of magnesium carbonate, and 44, the molecular mass of carbon dioxide, calcula
27、ted on the basis of the following reaction: MgCO3 MgO + CO2BS ISO 21869:200634.1.2.4 Precision The repeatability of the mass measurements is 2 %. 4.2 Loss in mass on heating 4.2.1 Moisture content 4.2.1.1 Apparatus 4.2.1.1.1 Weighing dish, low form, approx. 70 mm diameter and 30 mm high (tared). 4.2
28、.1.1.2 Oven, controlled at 115 C 10 C. 4.2.1.1.3 Analytical balance, accurate to 0,1 mg. 4.2.1.2 Procedure Weigh into the tared weighing dish 5 g of magnesium oxide to the nearest 1 mg. Spread the test portion to form an even layer in the bottom of the weighing dish. Place the dish, without its cove
29、r, in the oven with the temperature previously set at 115 C 10 C and dry to constant mass (to the nearest 1 mg). On removal from the oven, always place the cover on the weighing dish. Allow to cool in a desiccator. Weigh. The mass loss represents the moisture content. 4.2.1.3 Expression of results T
30、he moisture content is given by the equation: Moisture content (%) = m= 100(m1/m01) where m1is the mass loss after heating, in grams; m01is the original mass of the test portion, in grams. 4.2.2 Magnesium hydroxide content 4.2.2.1 Apparatus 4.2.2.1.1 Crucible (tared), platinum or porcelain. (If a po
31、rcelain crucible is used, it shall be heated to 390 C 20 C and cooled in a desiccator before the test.) 4.2.2.1.2 Furnace, capable of reaching 450 C 20 C. 4.2.2.1.3 Analytical balance, accurate to 0,1 mg. 4.2.2.2 Procedure Weigh into the tared crucible 2 g of magnesium oxide to the nearest 1 mg. Pla
32、ce the crucible containing the magnesium oxide in the furnace set at 390 C 20 C. BS ISO 21869:20064 If a porcelain crucible is used, raise the temperature gradually. When 390 C is reached, maintain it for 2 h in an oxidative atmosphere. Remove the crucible from the furnace, allow to cool in a desicc
33、ator and weigh. Repeat the calcination to verify that a constant mass was reached. It is preferable to allow a porcelain crucible to cool slowly in the furnace before placing it in the desiccator. The mass loss represents the moisture plus magnesium hydroxide content. 4.2.2.3 Expression of results T
34、he magnesium hydroxide content is given by the equation: Mg(OH)2(%) = 3,2 100(m2/m02) m = hwhere m2is the loss in mass after heating to 390 C, in grams; m02is the original mass of the test portion, in grams; mis the moisture content (determined as specified in 4.2.1), in grams; 3,2 is the ratio betw
35、een 58, the molecular mass of magnesium hydroxide, and 18, the molecular mass of water, calculated on the basis of the following reaction: Mg(OH)2 MgO + H2O 4.2.3 Magnesium carbonate content 4.2.3.1 Apparatus 4.2.3.1.1 Crucible (tared), platinum or porcelain. (If a porcelain crucible is used, it sha
36、ll be heated to over 700 C and cooled in a desiccator before the test.) 4.2.3.1.2 Furnace, capable of reaching over 700 C. 4.2.3.1.3 Analytical balance, accurate to 0,1 mg. 4.2.3.2 Procedure Weigh into the tared crucible 2 g of magnesium oxide to the nearest 1 mg. Place the crucible containing the m
37、agnesium oxide in a furnace set at over 700 C. If a porcelain crucible is used, raise the temperature gradually. When 700 C is reached maintain it for 2 h in an oxidative atmosphere. Remove the crucible from the furnace, allow to cool in a desiccator and weigh. Repeat the calcination to verify that
38、a constant mass was reached. It is preferable to allow a porcelain crucible to cool slowly in the furnace before placing it in the desiccator. The mass loss represents the moisture plus magnesium hydroxide plus magnesium carbonate content. BS ISO 21869:200654.2.3.3 Expression of results The magnesiu
39、m carbonate content is given by the equation: MgCO3(%) = 1,9 100(m3/m03) m h where m3is the loss in mass after heating to over 700 C, in grams; m03is the original mass of the test portion, in grams; mis the moisture content (determined as specified in 4.2.1), in grams; his the magnesium hydroxide co
40、ntent (determined as specified in 4.2.2), in grams; 1,9 is the ratio between 84, the molecular mass of magnesium carbonate, and 44, the molecular mass of carbon dioxide, calculated on the basis of the following reaction: MgCO3 MgO + CO2 4.2.4 Precision With an analytical balance accurate to 0,1 mg f
41、or 5 g, the repeatability of the mass measurements can be considered as 1 %. 5 Determination of the specific surface area The determination of the specific surface area shall be by the method described in ISO 4652-1 or ISO 18852. 6 Determination of the copper and manganese content 6.1 Principle A te
42、st portion is dissolved in hydrochloric acid and the resulting solution is analysed using atomic absorption or atomic emission spectrometry. Any silicates that may be present are removed using hydrofluoric and sulfuric acids. 6.2 Reagents During the analysis, unless stated otherwise, use only analyt
43、ical-quality reagents and distilled water or water of equivalent purity. 6.2.1 Hydrochloric acid, 20= 1,19 Mg/m3. 6.2.2 Hydrochloric acid, diluted 1+2. Dilute 1 volume of hydrochloric acid (6.2.1) with 2 volumes of water. 6.2.3 Sulfuric acid, 20= 1,84 Mg/m3. 6.2.4 Sulfuric acid, diluted 1+3. Pour ca
44、refully 1 volume of concentrated sulfuric acid (6.2.3) into 3 volumes of water. BS ISO 21869:20066 6.2.5 Hydrofluoric acid, 20= 1,13 Mg/m3. 6.2.6 Hydrogen peroxide, 30 % (by mass) solution. 6.2.7 Copper, reference solution corresponding to 1 g of copper per cubic decimetre. A commercially available
45、copper reference solution may be used, or the solution may be prepared in the following manner: Weigh, to the nearest 0,1 mg, 1 g of electrolytic copper (minimum purity: 99,9 %) and dissolve it in 50 cm3of concentrated hydrochloric acid (6.2.1). Add 15 cm3of hydrogen peroxide solution (6.2.6). After
46、 the copper has dissolved completely, decompose the excess hydrogen peroxide by boiling. Allow to cool and transfer to a one-mark 1 000 cm3volumetric flask (6.3.5). Make up to the mark and mix well. 1 cm3of this solution contains 1 000 g of copper. 6.2.8 Copper, reference solution corresponding to 1
47、0 mg of copper per cubic decimetre. Introduce precisely, using a pipette (6.3.6), 10 cm3of copper reference solution (6.2.7) into a one-mark 1 000 cm3volumetric flask (6.3.5), make up to the mark with diluted hydrochloric acid 1+2 (6.2.2) and mix well. Prepare this reference solution on the same day
48、 as it will be used. 1 cm3of this solution contains 10 g of copper. 6.2.9 Manganese, reference solution corresponding to 1 g of manganese per cubic decimetre. A commercially available manganese reference solution may be used, or the solution may be prepared in the following manner: Use electrolytic
49、manganese (minimum purity: 99,9 %), first cleaning its surface of oxides of manganese which may be present, as follows. Place a few grams of the metal in a beaker containing 60 cm3to 80 cm3of diluted (1+3) sulfuric acid (6.2.4) and about 100 cm3of water. Shake and, after a few minutes, pour off the acid solution and pour water into the beaker. Wash repeatedly with water. Place the cleaned manganese metal in acet
