The “ISO 1874 Plastics - Polyamide (PA) molding and extrusion materials” standard, developed by the International Organization for Standardization (ISO), consists of several subsections developed under the same title. Namely,
Types of polyamide plastics are distinguished from each other by a classification system based on appropriate levels of identifying properties:
The designation system is valid for all polyamide homopolymers and copolymers. It is valid for materials ready for normal use, unmodified and modified with colorants, additives, fillers, reinforcing materials, polymer modifiers and the like.
This standard does not apply to monomer cast polyamides of the PA 6 and PA 12 type. It does not imply that materials with the same designation will necessarily give the same performance. This standard does not provide engineering data, performance data or data on processing conditions that may be necessary to specify a material for a particular application or processing method. If such additional characteristics are required, they shall be determined in accordance with the test methods specified in ISO 1874-2, as appropriate. In order to specify a thermoplastic material for a particular application or repeatable processing, additional requirements may be given in the data block.
The classification system for thermoplastics is based on the standardized template shown in the table provided in the standard. The identification consists of an optional description block reading “thermoplastics” and an identification block consisting of the international standard number and an individual product block. For unambiguous identification, the individual product block is divided into five data blocks containing the following information:
This standard specifies procedures and conditions for preparing test specimens and procedures for measuring the properties of the materials from which these specimens are made. Properties and test methods suitable and necessary for characterizing polyamide molding and extrusion materials are listed.
The properties are selected from the general test methods included in ISO 10350-1. Other test methods commonly used or of special importance for these molding and extrusion materials are also included in ISO 1874-2, as are the defining properties found in ISO 1874-1 (viscosity number and tensile modulus of elasticity).
When preparing test samples, the material sample must have reached room temperature before molding. The moisture content of the material sample must not exceed 200 percent (mass fraction) if the viscosity number of the polyamide is at most 0,2 ml/g, and 200 percent (mass fraction) if the viscosity number of the polyamide is at least 0,1 ml/g.
For PA46, PA6T/66, PA6T/XT, PA6T/6I/66, PA6T/6I, PA6I/6T and PA NDT/INDT, the moisture content should be less than 0,1 percent (mass fraction). The moisture content of filled or reinforced materials should be expressed as a percentage of the total mass of the compound. The moisture content should be determined according to ISO 15512 and the viscosity number according to ISO 307. To ensure that the moisture content remains low, it is recommended that the sample material in the hopper of the injection molding machine be blanketed with a suitable gas (e.g. dried air, nitrogen or argon). Better results can be obtained by using a desiccant hopper dryer.
Injection moulded samples should be prepared in accordance with ISO 294-1 using the conditions specified in the table. Samples should be prepared by injection moulding from dry granules. It is essential that samples are always prepared by the same procedure using the same processing conditions. The material should be stored in moisture-proof containers until required for use.
To determine the properties, separate sets of test specimens are conditioned in two different ways: one set in the dry-moulded condition and the other in the moist condition. The properties are determined on the specimens in the dry-moulded condition or on the specimens in the moist condition or on both conditions.
Our organization, which has been trying to support businesses from every sector with its testing, measurement, analysis and evaluation studies carried out in a wide range for years, has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. In this context, testing services in accordance with the "ISO 1874 Plastics - Polyamide (PA) molding and extrusion materials" standard are also provided to businesses.
To get an appointment, to get more detailed information or to request an evaluation, you can ask us to fill in our form and reach you.
