Poly(p-phenylene oxide)
- Poly (oxy -2 ,6- dimethyl-1 ,4 -phenylene)
- Poly (2,6-dimethyl -1 ,4- phenylene oxide)
- PPO, PPE
- Polyphenylene oxide (deprecated)
Thermoplastic
Fixed
1.06 g · cm -3
215 ° C
2000 MPa ( Vestoran 1090 )
Dilute acids, strong alkalis, alcohol, detergents
Polyphenylene ether ( PPE abbreviations, and poly (oxy -2 ,6-dimethyl -1 ,4 -phenylene) or polyether, outdated polyphenylene oxide, called PPO ) is a high temperature resistant, thermoplastic material having the general formula ( C8H8O ) n Technically it is prepared by oxidative coupling of 2,6 -dimethylphenol. In pure form, PPE is hardly used, it is mainly used as a blend with polystyrene, high impact styrene -butadiene copolymer or polyamide.
History
Polyphenylene ether was discovered in 1956 by AS Hay and introduced to the market since 1960 by General Electric. The common name and polyphenylene oxide ( PPO) is incorrect because it is not an oxide but an ether.
Although he was considered one of the most cost-effective high-temperature resistant plastics, processing has been difficult and the impact strength and temperature resistance subsided with time. Mixing with polystyrene in any ratio the disadvantages of the properties could be compensated and also be selectively modified. In the late 1960s then modified PPE products came under the trade name Noryl on the market.
Properties
PPE is an amorphous high performance plastic. The glass transition temperature is 215 ° C but it can be modified by mixing with polystyrene in a wide range. The modification and addition of fillers such as glass fibers, the properties in a wide range can be modified.
Production
Substituting 2,6- xylenol, copper (II) - or copper ( II) chloride in pyridine in the presence of atmospheric oxygen, in a way, the generated polyphenylene ether. In the case of copper (I ) chloride, this first oxidized by air oxygen to the copper ( II) chloride. Then a Einelektronenübertargung of 2,6-xylenol is held on the copper ( II) chloride, which is reduced to copper (I ) chloride. The atmospheric oxygen oxidized the reduced species back to copper ( II) chloride. Two 2.6 - Xylenolradikale can now dimerize. The resulting dimer can be formed by single-electron transfer and a radical to react with a further 2.6 - Xylenolradikal; this reaction can be repeated n times and is called oxidative coupling. Since, in this reaction, water is produced as a condensation product is a polycondensation reaction.
Use
PPE blends find applications for molded parts in electronics, household and automotive sectors which require high heat resistance, dimensional stability and dimensional accuracy. But also in medical technology - eg for instruments to be sterilized often made of plastic - they are used. The PPE blends are characterized by resistance to hot water at low water absorption, high impact resistance, halogen-free fire protection and low density. Processing is carried out by injection molding or extrusion at a processing temperature depending on the type of between 260 ° C and 300 ° C. The surface can be printed, hot stamped, be painted or metallized. Welds are possible by means of heating, friction or ultrasonic welding. It can be bonded to the halogenated solvents or different adhesives.
Trade names
Trade name of polyphenylene ethers are the following:
- Artley ( PPE PE) of Sumitomo Chemical
- GECET ( PPE EPS) of Huntsman
- Iupiace ( PPE PE) by Mitsubishi Engineering -Plastics
- Lemalloy ( PPE PA) by Mitsubishi Engineering -Plastics
- Luranyl ( PPE PS) Romira GmbH
- Noryl ( PPE PS) SABIC
- Noryl EF ( PPE EPS) SABIC
- Noryl GTX ( PPE PA) SABIC
- Ultranyl ( PPE PA) from BASF
- Vestoran ( PPE PS) from Evonik Degussa, formerly Chemische Werke Hüls ( see Marl )
- Xyron ( PPE PE) of Asahi Chemical
Standardize
- ASTM D 4349-1996 polyphenylene ether (PPE ) Materials
- DIN EN ISO 28941-1 Plastics - polyphenylene ether ( PPE ) molding and extrusion materials - Part 1: Designation system and basis for specifications (2008)