With our long experience in plastics testing, we at Intertek-Polychemlab use a broad spectrum of tests to determine the characteristic properties of plastics either by the standard ISO and ASTM methods or by product-specific techniques, but we can also develop special methods at the request of our clients and in cooperation with them.

We make use of various test methods and applications to obtain the relevant data about the physical properties of plastics, using test specimens in the form of small plates, sheeting or film. By varying the conditions of the surroundings, such as temperature, we can evaluate the effect of these factors on certain properties and determine the resistance of plastics to them.

Physical tests are used for characterizing newly developed materials, for troubleshooting, and very often also for process and quality control.

Techniques and applications

• The density of non-foamed plastic articles is determined by immersion in distilled water, using the ISO 1183 method.

• The softening temperature, which is a measure of the resistance to deformation at elevated temperatures, can be determined in two ways. In one case, the specimen is subjected to a force at one point, as in measurement of the Vicat softening temperature (VST) by the ISO 306 method. Alternatively, the test specimen is subjected to a force at three points, as in the determination of the heat deflection temperature (HDT) by the ISO 75 method.

• The shrinkage behaviour of films can also be determined in two different ways. In one case, the percentage of shrinkage is measured as a function of the residence time in an oil bath at a certain temperature. Alternatively, the shrinkage stress is measured in a hot-air oven.

• The brittleness due to environmental stresses can be determined both by standard tests and by product-specific techniques designed to find out how well a notched specimen resists the combined effects of applied forces and environmental factors at a certain temperature when subjected to them for a certain length of time, these tests being as follows:
  • a flexural force is applied to the material, and the percent failure over a certain time is determined by the ASTM 1693 method.
  • alternatively, a tensile force is applied by a weight, and the time to failure is determined.

   

• The resistance of plastic test specimens to chemical and physical ageing is determined by immersing them into certain liquids at a given temperature for a set time and assessing various relevant parameters, such as swelling, change in weight, and the difference in mechanical characteristics by the ISO 175 method.

Contact and information

If you wish to receive more information on this subject from one of our experts, please contact Intertek Polychemlab by Email, or by telephone +31 46 476 27 13