Pentaplast

the trade name in the USSR for the polyether poly-3,3-bis(chloromethyl)oxetane, whose repeating unit is [—OCH₂C(CH₂Cl)₂CH₂—]_n. Pentaplast is a thermoplastic linear polymer with a 30-percent degree of crystallization and a molecular weight that ranges from 70,000 to 200,000. A hard, colorless substance, it is self-extinguishing and dissolves only in cyclohexanone and chlorobenzene at elevated temperatures. It resists the action of concentrated mineral acids at 100°C and is destroyed only by the action of strong oxidizing agents, for example, nitric acid and fuming sulfuric acid. Pentaplast is more stable than polyvinyl chloride and less so than fluoroplastics. Its strength indexes are similar to those of polypropylene.

Pentaplast is commercially prepared by the cationic or anionic polymerization of 3,3-bis(chloromethyl)oxetane in blocks or suspensions in organic solvents. It is suitable for injection molding and extrusion and has good adhesive properties. Pentaplast is used as an anticorrosive coating for chemical equipment and pipes, as cable insulation, and to make high-precision parts in mechanical engineering. In the United States, it is manufactured under the trade name Penton.

REFERENCE

Entsiklopediia polimerov, vol. 2. Moscow, 1974.

单词	pentaplast
释义	Pentaplast Pentaplast the trade name in the USSR for the polyether poly-3,3-bis(chloromethyl)oxetane, whose repeating unit is [—OCH₂C(CH₂Cl)₂CH₂—]_n. Pentaplast is a thermoplastic linear polymer with a 30-percent degree of crystallization and a molecular weight that ranges from 70,000 to 200,000. A hard, colorless substance, it is self-extinguishing and dissolves only in cyclohexanone and chlorobenzene at elevated temperatures. It resists the action of concentrated mineral acids at 100°C and is destroyed only by the action of strong oxidizing agents, for example, nitric acid and fuming sulfuric acid. Pentaplast is more stable than polyvinyl chloride and less so than fluoroplastics. Its strength indexes are similar to those of polypropylene. Pentaplast is commercially prepared by the cationic or anionic polymerization of 3,3-bis(chloromethyl)oxetane in blocks or suspensions in organic solvents. It is suitable for injection molding and extrusion and has good adhesive properties. Pentaplast is used as an anticorrosive coating for chemical equipment and pipes, as cable insulation, and to make high-precision parts in mechanical engineering. In the United States, it is manufactured under the trade name Penton. REFERENCE Entsiklopediia polimerov, vol. 2. Moscow, 1974.
随便看	hepatic portal venous system hepatic prominence hepatic pulse hepatic ratio hepatic s hepatics hepatic segment hepatic segments hepatic siderosis hepatic sinus of calori hepatic sinusoids hepatic sphincter hepatic s's hepatic steatosis hepatic stellate cell hepatic tanager hepatic tissue blood flow rates hepatic tissue water content hepatic transplant hepatic triad hepatic triglyceride lipase hepatic tubule hepatic tumor hepatic-type fatty-acid-binding protein hepatic uroporphyria caused by hexachlorobenzene