BS-ISO-15028-2004.pdf
《BS-ISO-15028-2004.pdf》由会员分享,可在线阅读,更多相关《BS-ISO-15028-2004.pdf(12页珍藏版)》请在三一文库上搜索。
1、BRITISH STANDARD BS ISO 15028:2004 Plastics Aromatic isocyanates for use in the production of polyurethanes Determination of hydrolysable chlorine ICS 83.080.10 ? BS ISO 15028:2004 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2
2、006 BSI 2006 ISBN 0 580 49530 2 National foreword This British Standard was published by BSI. It is the UK implementation of ISO 15028:2004. The UK participation in its preparation was entrusted to Technical Committee PRI/82, Thermoplastic materials. A list of organizations represented on PRI/82 can
3、 be obtained on request to its secretary. 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 cannot confer immunity from legal obligations. Amendments issued since publication
4、Amd. No. DateComments Reference number ISO 15028:2004(E) INTERNATIONAL STANDARD ISO 15028 First edition 2004-07-15 Plastics Aromatic isocyanates for use in the production of polyurethanes Determination of hydrolysable chlorine Plastiques Isocyanates aromatiques pour utilisation dans la production de
5、 polyurthannes Dtermination du chlore hydrolysable BS ISO 15028:2004 ii iii 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
6、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 collaborates clo
7、sely 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 Standards. Dra
8、ft 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 this docu
9、ment may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 15028 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 12, Thermosetting materials. BS ISO 15028:2004 iv Introduction No International Standard for t
10、he determination of hydrolysable chlorine in isocyanates has been published. The main sources of hydrolysable chlorine in isocyanates are carbamoyl chloride and dissolved phosgene from the manufacturing process. Both of these compounds react with alcohols and water, forming ureas, carbamates, carbon
11、 dioxide and hydrochloric acid. These acidic materials neutralize basic catalysts used in polyurethane production, thus adversely affecting processing properties. This test method is based on and is technically equivalent to ASTM D 4663-98, Standard Test Method for Polyurethane Raw Materials: Determ
12、ination of Hydrolyzable Chlorine of Isocyanates. BS ISO 15028:2004 1 Plastics Aromatic isocyanates for use in the production of polyurethanes Determination of hydrolysable chlorine WARNING Persons using this International Standard should be familiar with normal laboratory practice. This standard doe
13、s not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions prior to use. 1 Scope This International S
14、tandard specifies a method for the determination of the hydrolysable-chlorine content of toluene-2,4-diisocyanate, toluene-2,6-diisocyanate or mixtures of the two. This test method may also be applied to other isocyanates of suitable solubility, such as crude or refined polymeric isocyanates. 2 Norm
15、ative 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 385-1, Laboratory glassware
16、Burettes Part 1: General requirements ISO 648, Laboratory glassware One-mark pipettes ISO 3696:1987, Water for analytical laboratory use Specification and test methods ISO 4787, Laboratory glassware Volumetric glassware Methods for use and testing of capacity ISO 6353-2, Reagents for chemical analys
17、is Part 2: Specifications First series 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 TDI toluenediisocyanate 3.2 polyurethane polymer prepared by the reaction of an organic di- or polyisocyanate with compounds containing two or more hydroxy
18、l groups 3.3 hydrolysable chlorine organic or inorganic chlorine compounds formed in the production of isocyanates that react with methanol under the conditions of the test to liberate hydrogen chloride BS ISO 15028:2004 2 4 Principle The hydrolysable chlorine reacts with methanol, liberating hydrog
19、en chloride. The titratable chlorides are then determined potentiometrically using a standard silver nitrate solution. 5 Interference Thiocyanate, cyanide, sulfide, bromide, iodide and other substances capable of reacting with silver ions, as well as substances capable of reducing silver ions in aci
20、d solution, will interfere with the determination. 6 Sampling Since organic isocyanates react with atmospheric moisture, take special precautions in sampling. Usual sampling methods (for example, sampling an open drum with a thief), even when conducted rapidly, can cause contamination of the sample
21、with insoluble ureas; therefore, blanket the sample with a dry inert gas (e.g. nitrogen, argon or dried air) at all times. WARNING Organic isocyanates are hazardous when absorbed through the skin, or when the vapours are breathed in. Provide adequate ventilation and wear protective gloves and eyegla
22、sses. 7 Reagents Reagent-grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all reagents shall conform to the specifications of ISO 6353-2. Other grades may be used, provided that it is first determined that the reagent is of sufficiently high purity to permi
23、t its use without lessening the accuracy of the determination. Unless otherwise indicated, references to water shall be understood to mean grade 2 water as defined by ISO 3696:1987. 7.1 Concentrated nitric acid, HNO3, specific gravity 1,42, conforming to ISO 6353-2. 7.2 Methanol, CH3OH, conforming t
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- BS ISO 15028 2004
链接地址:https://www.31doc.com/p-3748538.html