Polyphenylene oxide chemical resistance

Polypropylene has a chemical resistance about the same as that of polyethylene, but it can be used at 120°C (250°F). Polycarbonate is a relatively high-temperature plastic. It can be used up to 150°C (300°F). Resistance to mineral acids is good. Strong alkalies slowly decompose it, but mild alkalies do not. It is partially soluble in aromatic solvents and soluble in chlorinated hydrocarbons. Polyphenylene oxide has good resistance to ahphatic solvents, acids, and bases but poor resistance to esters, ketones, and aromatic or chlorinated solvents. 

Polyphenylene oxide modified Very fough engineering plastic, superior dimensional stability, low moisture absorption, excellent chemical resistance Injection molding... 

Chemical Resistance - Modified Polyphenylene Ether / Oxide... 

Results of some of these short-term tests are shown in Table II. A comparison is given between PPS and five other plastics nylon (Zytel 101), polycarbonate (Lexan 141), polysulfone (Bakelite Polysulfone), polyphenylene oxide (Noryl), and polyetherimide (Ultem 2300). The data presented are based upon retention of tensile strength for all plastics except the Ultem 2300, which is based upon retention of flexural strength. Unsuccessful attempts were made to injection mold ASTM Type IV tensile bars out of the Ultem compound, but flexural strength bars could be made. Experience has shown that chemical resistance tests monitored by flexural strength retention are comparable to those monitored by retention of tensile strength. 

In 1985 General Electric launched two new resins for car exteriors—Noryl GTX, a polyphenylene oxide (PPO)/nylon blend for fenders and other panels, and Lomod polyether ester elastomers for bumper systems. Noryl GTX combines the heat and dimensional stability and the low water absorption of PPO with the chemical resistance of semicrystalline nylons. 

Uses Disinfectant solvent for wire enamels pharmaceuticals insecticides fungicides herbicides plasticizers mbber chemicals paints additives to lubricants and gasoline mfg. of polyphenylene oxide wetting agents dyestuff synthetic resin comonomer for alkali-resist, phenolic resins froth flotation agent engine cleaner ingred. 

In more recent times GE Plastics has upgraded their Noryl range of PS-modified polyphenylene oxide materials without recourse to halogens. Improved flame retardant properties are found in the new Noryl GTX 4110 series, which uses a proprietary flame retardancy system free from halogens and red phosphorus. The compound has high heat and chemical resistance. 

Exterior door handles are another application that has turned to plastics to balance chemical resistance and mechanical properties. Many filled thermoplastics such as blends of PC and polybutylene terephthalate (PBT), polyethylene terephthalate (PET), and nylon have been tried or used in this application, with nylon as the clear wirmer. Exterior mirror housings likewise use many thermoplastic solutions such as ABS, PC/ABS, blends of polyphenylene oxide (PPO) and polystyrene (PS), nylon, blends of PP and ethylene propylene diene monomer (EPDM), and weatherable ABS. Again, nylon clearly dominates this application in terms of volume. Many other exterior parts continue to adopt thermoplastic solutions. Figure 14 shows an impingement shield constructed from LGF PP. 

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