Injection Molding and Extrusion

Polyamides are among the earliest categories of engineering plastics and still hold the most significant position within this group. Their excellent thermal and mechanical properties have led to widespread use in specialized applications, often replacing metal parts—particularly in the automotive industry. Polyamides constitute a relatively large family of polymers, with PA6 and PA66 being the most widely used, accounting for over 90% of total polyamide consumption.

Technical Features of Polyamides

• Thanks to the presence of strong hydrogen bonds in their structure and their crystalline nature, polyamides exhibit highly desirable strength.
• Adding other agents, such as glass fibers as reinforcements, enhances the resistance of parts against deformation at elevated temperatures, notably increasing the HDT (Heat Deflection Temperature).
• The spatial and molecular structure of polyamides results in a narrow melting point range, caused by the rapid breakage of hydrogen bonds at specific temperatures and a quick decrease in the polymer’s
• viscosity.
• Their recyclability and reusability make them an attractive choice for manufacturers.

Sensitivity of Polyamides
A key characteristic of polyamides is their high water absorption, attributed to the presence of polar amide groups surrounding water molecules within their structure. Water acts as a plasticizer, disrupting hydrogen bonds and making the polymer more flexible, though it reduces tensile strength and increases impact resistance. The moisture absorption is evaluated either through the degree of crystallinity or by measuring the density of the amide groups. Aromatic monomers tend to reduce water uptake. For example, Nylon 6 absorbs more moisture than Nylon 66 due to its lower degree of crystallinity.