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6PPD itself is deadly to rotifers, especially in combination with sodium chloride, though not at the level generally found in the runoff from road salt. [21] A small-scale biomonitoring study in South China has shown both 6PPD and 6PPDQ to be present in human urine; concentrations were low but the health implications are unknown. [ 22 ]
p-Phenylenediamine (PPD) is an organic compound with the formula C 6 H 4 (NH 2) 2. This derivative of aniline is a white solid, but samples can darken due to air oxidation. [1] It is mainly used as a component of engineering polymers and composites like kevlar. It is also an ingredient in hair dyes and is occasionally used as a substitute for ...
m-Phenylenediamine, also called 1,3-diaminobenzene, is an organic compound with the formula C 6 H 4 (NH 2) 2. It is an isomer of o -phenylenediamine and p -phenylenediamine . This aromatic diamine is a colourless solid that appears as needles, but turns red or purple on exposure to air due to formation of oxidation products. [ 3 ]
It is typically prepared by dissolving 1 gram of PD, 10 grams of sodium sulfite, and 0.5 millilitres of detergent in 100 millilitres of water; initially pink in colour, the solution becomes purple with age. Steiner's solution will last for months. [5] The phenylenediamine reacts with aldehydes to yield Schiff bases according to the following ...
Aromatic polyimides are synthesized by the reaction of dianhydrides with diamines, for example, pyromellitic anhydride with p-phenylenediamine. It can also be accomplished using diisocyanates in place of diamines. Solubility considerations sometimes suggest use of the half acid-half ester of the dianhydride, instead of the dianhydride itself.
Phenylenediamine may refer to: o-phenylenediamine or OPD, a chemical compound C 6 H 4 (NH 2) 2; m-phenylenediamine or MPD, a chemical compound C 6 H 4 (NH 2) 2; p-phenylenediamine or PPD, a chemical compound C 6 H 4 (NH 2) 2; N,N-dimethyl-p-phenylenediamine or DMPD; N,N,N′,N′-tetramethyl-p-phenylenediamine or TMPD, used in microbiology; N,N ...
These are primarily derivatives of p-phenylenediamine (PPD) and work by reacting with ozone faster than it can react with vulnerable functional groups in the polymer (typically alkene groups). They achieve this by having a low ionization energy which allows them to react with ozone via electron transfer, this converts them into radical cations ...
The reaction of quadricyclane with DEAD is a 2σ + 2σ + 2π cycloaddition that on water takes place within 10 minutes at room temperature with 82% yield. The same reaction in toluene takes 24 hours at 80 °C with 70% yield. An emulsion reaction in fluorinated cyclohexane takes 36 hours and the neat reaction takes even longer (48 hours).