塑料. 热塑性塑料熔融状态下的拉伸特性测定

[中文适用范围]： 本文件规定了测定熔融塑料的拉伸和断裂特性的方法。 该方法涉及测量在规定的挤出温度和拉伸条件下熔融长丝变形时产生的力。 数据是在非等温和非均匀变形条件下生成的。 然而，它对于解释聚合物在拉伸流动中的行为很有用。 该方法适用于热塑性塑料模塑和挤出材料，这些材料可以使用毛细管挤出流变仪或具有毛细管棒模头的挤出机或其他挤出装置进行挤出，并且具有足够的熔体强度，可以毫无困难地进行处理。 该方法适用于化学稳定的材料，可产生不含异质性、气泡、未熔化杂质等的均匀挤出物。 该方法可以提供以下信息： ——所有挤出技术的可加工性， — 机械和热历史的影响，以及 — 影响化学结构，例如支化、缠结和分子质量。 该技术是可用于测量材料的拉伸流动行为的多种技术之一。 这种测量方法不一定再现热塑性塑料在加工过程中所经历的拉伸条件。 [外文原描述]： This document specifies a method for determining the drawing and break characteristics of molten plastics. The method involves the measurement of the force generated in deforming a molten filament under defined extrusion temperature and drawing conditions. Data is generated under non-isothermal and non-homogeneous deformation conditions. However, it is useful for the interpretation of polymer behaviour in extensional flow. The method is suitable for thermoplastics moulding and extrusion materials that can be extruded using a capillary extrusion rheometer, or an extruder with capillary rod die or other extrusion devices and have sufficient melt strength to be handled without difficulty. The method is applicable to chemically stable materials that produce a uniform extrudate free from heterogeneities, bubbles, unmelted impurities, etc. This method can provide information on — processability for all extrusion techniques, — the effect of mechanical and thermal history, and — the effect of chemical structure, such as branching, entanglements and molecular mass. This technique is one of a number of techniques that can be used to measure the extensional flow behaviour of a material. This method of measurement does not necessarily reproduce the drawing conditions to which thermoplastics are subjected to during their processing.