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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 ...
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 ...
6PPD is an organic chemical widely used as stabilising additive (or antidegradant) in rubbers, such as NR, SBR and BR; all of which are common in vehicle tires. [1] Although it is an effective antioxidant it is primarily used because of its excellent antiozonant performance.
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 ]
Synthesis of benzotriazole involves the reaction of o-phenylenediamine, sodium nitrite, and acetic acid. The conversion proceeds via diazotization of one of the amine groups: [7] [8] The synthesis can be improved when the reaction is carried out at low temperatures (5–10 °C) and briefly sonicated in an ultrasonic bath. [9]
N-Isopropyl-N′-phenyl-1,4-phenylenediamine (often abbreviated IPPD) is an organic compound commonly used as an antiozonant in rubbers. [1] Like other p-phenylenediamine -based antiozonants it works by virtue of its low ionization energy , which allows it to react with ozone faster than ozone will react with rubber. [ 2 ]
It can be absorbed into the intestinal wall [4] and may cause foreign-body granulomatous reactions in some rat species. These reactions might not occur in humans, however. [9] Some evidence suggests that it engenders a lack of carcinogenicity. [10] If liquid paraffin enters the lungs, it can cause lipoid pneumonia. [4]
The general reaction catalyzed by a phosphatase enzyme. Phosphatases catalyze the hydrolysis of a phosphomonoester, removing a phosphate moiety from the substrate. Water is split in the reaction, with the -OH group attaching to the phosphate ion, and the H+ protonating the hydroxyl group of the other product. The net result of the reaction is ...