Phenolic resin

Phenolic resins are among the first fully synthetic plastics to be developed. In 1907, the chemist Leo Hendrik Baekeland filed the patent for this thermoset produced by polycondensation. He brought this material to market under the trade name Bakelite. Bakelite was distinguished by remarkable electrical and mechanical properties, which made it a sought-after material in the emerging electrical industry. It was frequently used for the manufacture of housings and functional parts that required both robustness and a high insulating capacity.

Technical characteristics

Phenolic resins reinforced with organic fillers exhibit a wide range of advantageous properties:

• High stiffness and hardness: These plastics are very stiff and hard, which makes them particularly resistant to mechanical loads.
• Low creep tendency: They show hardly any tendency to yield or deform under sustained load.
• High heat deflection resistance: Phenolic resins remain dimensionally stable even at high temperatures and do not lose their structural integrity.
• Low thermal expansion: They expand only minimally when heated, which makes them ideal for applications where precise dimensions are important.
• High resistance to glowing: These resins are extremely resistant to ignition and withstand high temperatures without melting or burning.
• Flame retardant: Phenolic resins are flame retardant and thereby contribute to safety in many applications.

Colour limitations and areas of application

Due to their chemical structure, phenolic resins can only be coloured in dark shades. While this somewhat limits the aesthetic possibilities, it does not impair their functional properties. A significant disadvantage, however, is that these plastics are not suitable for use in food applications. This is because they can release certain substances that may be a health concern.