Please note that we only supply polymer in granular form for Injection Moulding or Extrusion applications. We do not supply polymer in rod, sheet or block form.

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    How useful is Tensile Strength data ?

    When scanning a thermoplastics data sheet for a new project or finding a replacement for an existing grade, the eye tends to get drawn to the values quoted for tensile strength (or more correctly ‘tensile stress at break’) as an indication of the material’s mechanical properties.  Although tensile stress is a useful property for metals, it is of less value when dealing with thermoplastics.  Applied loads during product service life are more likely to be in compression or in bend than in pure tension… with a few notable exceptions.  Secondly, rupture under an applied tensile load is very seldom the cause of product failure in a plastics component.   A more likely cause is unacceptable deformation or distortion. That is an entirely different property, related to the tensile or flexural modulus (stiffness) and component geometry.

    Another reason for not reading too much into tensile strength data?  The value listed in data sheets is a snapshot. It is derived from a standard test. This is carried out under a specific combination of temperature and strain rate. (This is the rate at which the test piece is stretched).  Changing temperature and strain rate can significantly alter the resulting value for tensile strength (and also the elongation at break).  The ultimate elongation is also influenced by the presence of flaws and imperfections in the material.

    Is the product is going to be subjected to mechanical stresses during its service life? It would be prudent to pay more attention to the values of modulus (stiffness) and impact data rather than tensile strength. However, data for impact can give a false sense of security and needs careful interpretation.

    tensile graphs

    For information on all the specified grades that we can offer please contact us today or also try our polymer search.

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    How do electrostatic dissipative (esd) thermoplastics work?

    When two polymeric surfaces are rubbed together static electrical charges are generated on the surfaces. Party tricks involving picking up pieces of paper with a comb are amusing. However, static electricity can be a nuisance in the plastics industry with dust attraction during storage or in service.

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    Does FR imply fire resistance?

    When we see ‘FR’ in a plastics grade coding we can sometimes be lulled into believing we have a material that is ‘fire resistant’.

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    Does the coding for Polyamides mean anything to designers and processors?

    Polyamides are macromolecules with repeating units linked by amide bonds. Polyamides occur both naturally and artificially. Examples of naturally occurring polyamides are proteins, such as wool and silk.

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