Polyphenylene ether PPE alloys - economic aspects

PPE is obtained by oxidative polymerization of 2.6-dimethylphenol, with copper compounds as catalyst. However, the pure polymer discovered by General Electric was virtually impossible to process. In 1964, General Electric modified PPE by alloying it with impact PS, with a wide range of grades adaptable to different processing methods and applications. This range includes self-extinguishing resins without halogenated additives and grades reinforced with glass fibers, with or without flame retardancy.

PPE is always used in the form of alloys. Originally, the first and only alloy was with impact PS, in varying proportions, with properties that improved the higher the proportion of PPE. Subsequently, other types of PPE alloys were developed, including the most successful: the alloy with PA polyamides. Other polymers can also be alloyed with PPE, but in smaller tonnages than PPE/PS and PPE/PA. These include PPE/PBT and PPE/PPS, for the record.

Alloys with PA (Noryl GTX, originally launched by General Electric Plastics, now Sabic) offer interesting combinations of properties for large car body parts to be painted inline.

A new product had been developed jointly by Shell and General Electric Plastics, expanded PS modified with PPE, Caril, using pentane as an expanding agent. Applications were envisaged in the packaging, construction, furniture and automotive industries. This type of foam is already used in Japan by Kanegafuchi for microwave dishes. However, Shell's move away from plastics led to the abandonment of this development.

Please refer to the "Polyphenylene ether PPE. Polyarylene sulfone (PSU, PES, PAS)" [AM 3392] for more information.