NF EN ISO 2898-1

La présente norme décrit et explicite le système de désignation des résines d'homopolymères polyamides pour moulage et extrusion sur la base du système de désignation international utilisé au TC 61. La désignation comprend quatre parties comportant respectivement et successivement : le symbole, l'application envisagée ou le procédé de transformation, les caractéristiques essentielles, les propriétés de désignation. Pour les trois dernières parties, les informations sont codées à l'aide de lettres ou de chiffres dont les significations sont précisées dans la norme. Les éléments déterminants qui permettent de lire la désignation sont la référence de la norme en tête, puis l'ordre dans lequel se succèdent les lettres et les chiffres.

<p><b>1.1</b> This document establishes a system of designation for plasticized PVC thermoplastic material which can be used as the basis for specifications.</p> <p><b>1.2</b> The types of PVC-U plastics are differentiated from each other by a classification system based on appropriate levels of the designatory properties</p> <p>a) Shore hardness,</p> <p>b) density,</p> <p>c) torsional-stiffness temperature at 300 MPa,</p> <p>and on information about physical form, intended application and/or method of processing, important properties, additives, colorants.</p> <p><b>1.3</b> This document is applicable to all plasticized compositions of homopolymers and copolymers that contain at least a mass percentage of 50 % of vinyl chloride. It is also applicable to plasticized compositions containing chlorinated poly (vinyl chloride) and to plasticized compositions containing blends of one or more of the above-mentioned polymers, provided that the total amount of these polymers represents at least a mass percentage of 50 % of the polymer content of the composition.</p> <p>This document applies to materials ready for normal use in the form of powder (dry blends), granules or pellets and to materials unmodified or modified by colorants, additives, fillers, etc. It does not apply to cellular plastics or to paste compositions (plastisols).</p> <p><b>1.4</b> This document does not intend to imply that materials having the same designation give the same performance. It does not provide engineering data, performance data or data on processing conditions which might be required to specify a material for a particular application and/or method of processing.</p> <p>If additional properties are required, they are, if suitable, determined using the test methods specified in ISO 24023-2.</p> <p><b>1.5</b> In order to specify a thermoplastic material for a particular application or to ensure reproducible processing, additional requirements can be given in data block 5 (see 4.1).</p>