摘要:
Cyclic N-vinylacylamines are prepared by heating carbonic acid esters of cyclic N-2-hydroxyethylacylamines in the presence of a catalytic amount of alkali or alkaline earth metal compound having an alkaline reaction and subsequently distilling the reaction mixture.Cyclic N-vinylacylamines are valuable precursors for preparing plant protection agents and medicaments and serve as polymerization and copolymerization components for preparing plastics, surface coatings, paints and ion exchange materials.
摘要:
A process for preparing a dialkyl carbonate which comprises contacting an alkylene oxide with an aliphatic or cycloaliphatic alcohol and carbon dioxide in the presence of a catalyst at an elevated temperature.
摘要:
A process for the production of aromatic carbonic acid esters by transesterifying a mixture of dimethylcarbonamate/methanol and a methanol-immiscible azeotrope former for methanol with phenols in the presence of transesterification catalysts.
摘要:
A process for preparing a dialkyl carbonate by contacting a glycol carbonate with an alcohol at an elevated temperature in the presence of a thallium compound.
摘要:
An improved process for the preparation of a dialkyl carbonate by contacting a glycol carbonate with alcohol at an elevated temperature in the presence of an alkali metal or alkali metal compound, the improvement residing in employing less than 0.01 percent by weight of alkali metal and/or alkali metal compound, based upon the weight the reaction mixture.
摘要:
The present invention relates to a process for the preparation of polycarbonates which contain aliphatically bound hydroxyl groups by transesterification of aliphatic dihydroxy compounds with glycol carbonate, optionally in the presence of transesterification catalysts, with simultaneous separation of the glycol by fractional distillation, which process is characterized in that ethylene glycol is removed from the reaction mixture as an azeotropic mixture by means of inert solvents with which ethylene glycol is substantially immiscible. The present invention further relates to the preparation of polyurethanes from these polycarbonates.
摘要:
A process for the preparation of a diaryl carbonate by the reaction of an aromatic monohydroxy compound with phosgene under elimination of hydrogen chloride, wherein said reaction is carried out in the presence of a catalytic quantity of an aromatic heterocyclic basic nitrogen compound, or a salt thereof, or an adduct thereof formed under the reaction conditions.
摘要:
New cyclic carbonic acid derivatives of the formula ##STR1## in which R denotes either --CH.sub.2 OH, R.sup.1 then representing an alkyl radical having 1 to 4 C atoms, or ##STR2## R.sup.1 and R.sup.2 then independently of one another representing methyl or ethyl, or ##STR3## R.sup.1 and R.sup.3 then each representing an alkyl radical having 1 to 4 C atoms,or in whichR and R.sup.1 together denote ##STR4## wherein A represents the group ##STR5## or oxygen, a process for their preparation, and their use as copolymerization components in the preparation of polycarbonates.
摘要:
In a process for the preparation of dimethyl carbonate by reacting methanol with phosgene and/or methyl chloroformate, the improvement wherein the reaction is carried out in the presence of an aqueous alkali metal hydroxide solution and in the presence of an inert, water-immiscible organic solvent, at a temperature in the range from -20.degree. C. to +40.degree. C.
摘要:
A process for producing an anionic copolymer containing urethane and carboxylic acid ester moieties with or without carbonate moieties, carbonamide moieties, or both carbonate and carbonamide moieties, having weight average molecular weights from 1,000 to 150,000, determined by light diffusion method, which comprises heating an anhydrous mixture of 20 to 80% by weight of lactam and 80 to 20% by weight of a cyclic carbonate at temperatures between 100.degree. and 250.degree. C. in the presence of 0.001 to 1% by weight, based on the quantity of monomers, of an alkaline catalyst and copolymers produced thereby which are useful as adhesives, plasticizers and lacquers.