Search results
Results from the WOW.Com Content Network
Commercial phenyl ether polymers belong to two chemical classes: polyphenyl ethers (PPEs) and polyphenylene oxides (PPOs). The phenoxy groups in the former class of polymers do not contain any substituents whereas those in the latter class contain 2 to 4 alkyl groups on the phenyl ring.
Poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE), poly(oxy-2,6-dimethyl-1,4-phenylene), often referred to simply as polyphenylene oxide, is a high-temperature thermoplastic with the general formula (C 8 H 8 O) n. It is rarely used in its pure form due to difficulties in processing.
The NORYL family of modified resins consists of amorphous blends of polyphenylene oxides (PPO) or polyphenylene ether (PPE) resins with polystyrene.They combine the inherent benefits of PPE resin (affordable high heat resistance, good electrical insulation properties, excellent hydrolytic stability and the ability to use non-halogen fire retardant packages), with excellent dimensional ...
Acid rain is rain or any other form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH).Most water, including drinking water, has a neutral pH that exists between 6.5 and 8.5, but acid rain has a pH level lower than this and ranges from 4–5 on average.
Ether groups allow a free rotation of the polymer chains. This leads to a significantly reduced melting point and also improves the mechanical properties by an increased impact strength . [ 7 ] The alkyl groups in bisphenol A act also as a flexible element.
This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture.
The structure of the repeating unit of PPP Space-filling model of a short section of PPP. Poly(p-phenylene) (PPP) is made of repeating p-phenylene units, which act as the precursor to a conducting polymer of the rigid-rod polymer family.
Polyphenylene sulfide is a useful high temperature plastic. Coenzyme M, CH 3 SCH 2 CH 2 SO − 3, is the precursor to methane (i.e. natural gas) via the process of methanogenesis. Selected thioethers, from left: dimethylsulfide, coenzyme-M, the amino acid methionine, the vitamin biotin, and the engineering plastic polyphenylene sulfide.