Plastics - Ultra-high-molecular-weight polyethylene (PE-UHMW) moulding and extrusion materials - Part 1: Designation system and basis for specifications
This document establishes a system of designation for thermoplastic PE-UHMW materials@ which can be used as the basis for specifications. For the purposes of this document@ PE-UHMW materials are polyethylene materials having a melt massflow rate (MFR) of less than 0@1 g/10 min@ measured at 190 ??and 21@6 kg load. NOTE It has been confirmed that the melt volume-flow rate (MVR) is useful for characterizing some PE-UHMW materials (e.g. pipe materials) under the test condition of 230 ??21@6 kg and bore diameter of die with 3@628 mm (see ISO 21304-2). The types of PE-UHMW are differentiated from each other by a classification system based on appropriate levels of the designatory properties: a) viscosity number; b) elongational stress; c) Charpy double-notched impact strength; and on information about the intended application and/or method of processing@ important properties@ additives@ colorants@ fillers and reinforcing materials. This designation system is applicable to all PE-UHMW homopolymers and to ultra-high-molecularweight copolymers of ethylene having a content of other 1-olefinic monomers of less than 50 % by mass and a content of non-olefinic monomers with functional groups up to a maximum of 3 % by mass. It applies to materials ready for normal use in the form of powder@ granules or pellets@ unmodified or modified by colorants@ fillers and other additives. It is not intended to imply that materials having the same designation give necessarily the same performance. This document does not provide engineering data@ performance data or data on processing conditions which can be required to specify a material. If such additional properties are required@ they are intended to be determined in accordance with the test methods specified in ISO 21304?2@ if suitable. In order to specify a thermoplastic PE-UHMW material to meet particular specifications@ the requirements are to be given in data block 5 (see 4.1).