摘要:
Propylene oxide is added to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst in an amount of from 0.05 to 0.5 mole per mole of the active hydrogen compound at a reaction temperature of from 60 to 98.degree. C. at a reaction pressure less than or equal to 4 kg/cm.sup.2 to prepare a polyoxyalkylene polyol which has a hydroxyl value of from 10 to 35 mg KOH/g, a monool content less than or equal to 15 mol %, a Head-to-Tail bond selectivity greater than or equal to 96 percent, and low viscosity. A polymer polyol is prepared by polymerizing an ethylenically unsaturated monomer in the polyoxyalkylene polyol. A flexible polyurethane foam is prepared by reacting the polyoxyalkylene polyol or the polymer polyol with an organic polyisocyanate compound in the presence of a foaming agent, a catalyst, a surfactant, a crosslinking agent and other additives. The thus-obtained polyurethane foams have less closed cells and are more excellent in properties such as hardness, humid aged compression set and impact resiliency.
摘要:
Propylene oxide is added to an active hydrogen compound in the presence of an alkali metal hydroxide catalyst in an amount of from 0.05 to 0.5 mole per mole of the active hydrogen compound at a reaction temperature of from 60.degree. to 98.degree. C. at a reaction pressure less than or equal to 4 kg/cm.sup.2 to prepare a polyoxyalkylene polyol which has a hydroxyl value of from 10 to 35 mg KOH/g, a monool content less than or equal to 15 mol %, a Head-to-Tail bond selectivity greater than or equal to 96 percent, and low viscosity. A polymer polyol is prepared by polymerizing an ethylenically unsaturated monomer in the polyoxyalkylene polyol. A flexible polyurethane foam is prepared by reacting the polyoxyalkylene polyol or the polymer polyol with an organic polyisocyanate compound in the presence of a foaming agent, a catalyst, a surfactant, a crosslinking agent and other additives. The thus-obtained polyurethane foams have less closed cells and are more excellent in properties such as hardness, humid aged compression set and impact resiliency.
摘要:
An alkali metal compound such as metallic cesium, cesium hydroxide, cesium hydroxide monohydrate, metallic rubidium, rubidium hydroxide or rubidium hydroxide monohydrate is used as a catalyst, crude polyoxyalkylene polyol containing the catalyst is neutralized with a mineral acid or an organic acid, an aqueous solution layer containing an alkali metal salt is brought into contact with an anion exchange resin to adsorb mineral acid anion or organic acid anion, the alkali metal compound catalyst is recovered, alkylene oxide undergoes ring-opening addition polymerization on an active hydrogen compound in the presence of the recovered alkali metal compound catalyst to prepare polyoxyalkylene polyol, the catalyst is thereafter separated, recovered and reused, and such recycle of the alkali metal compound catalyst provides an economical process.
摘要:
An alkali metal compound such as metallic cesium, cesium hydroxide, cesium hydroxide monohydrate, metallic rubidium, rubidium hydroxide or rubidium hydroxide monohydrate is used as a catalyst, crude polyoxyalkylene polyol containing the catalyst is neutralized with a mineral acid or an organic acid, an aqueous solution layer containing an alkali metal salt is brought into contact with an anion exchange resin to adsorb mineral acid anion or organic acid anion, the alkali metal compound catalyst is recovered. alkylene oxide undergoes ring-opening addition polymerization on an active hydrogen compound in the presence of the recovered alkali metal compound catalyst to prepare polyoxyalkylene polyol, the catalyst is thereafter separated, recovered and reused, and such recycle of the alkali metal compound catalyst provides an economical process.