摘要:
A catalytic agent for etherifying, hydrogenating and isomerizing crude C.sub.4 -C.sub.8 -- hydrocarbon mixtures having a sulfur content, comprising a macroporous or gel cation exchanger having SO.sub.3 H groups and being charged with a mixture of a metal selected from the group consisting of Pd, Ru, Rh and Pt with a metal selected from the group consisting of Fe, Co, Ni, Cu, Ag and W.
摘要:
A catalytic method for preparing thermoplastic carbonate polymers is disclosed. In the method according to the interfacial polycondensation process or the homogeneous solution process, resins which containing catalytically active groups are used as catalysts. The resulting resins are characterized by their color stability and temperature stability.
摘要:
Polymers of improved surface quality are obtained by polymerization of microencapsulated monomer droplets suspended in an aqueous phase if the monomer and/or the aqueous phase contain a polymerization inhibitor.
摘要:
Suspension polymers having high swellability have low contents of soluble fractions if aliphatic peroxy esters are used as polymerization initiators.
摘要:
N-Substituted cyclic imides are obtained by reacting a cyclic acid anhydride with an amine in the presence of a solvent and an acid catalyst at 80.degree. to 200.degree. C. and with removal of the water formed, it being particularly advantageous to carry out this reaction in the presence of a stabilizer and an inert, dipolar aprotic cosolvent, optionally to add an inert organic solvent of low or zero polarity to the reaction mixture present after the reaction, to add a non-aqueous base in an amount of 0.5 to 50% by weight, based on the cyclic anhydride of the formula (II) used, and to separate off the precipitate formed to give a filtrate containing the N-substituted cyclic imide.
摘要:
New Synthetic resins useful as inert material for separating layers in ion exchanger mixed bed filters. The new synthetic resins are copolymers of(a) substituted styrenes and/or methacrylates,(b) methacrylates of polyhydric alcohols and/or aromatic polyvinyl compounds and(c) unsaturated hydrocarbons which have at least two allyl groupings in the molecule, and/or polyvinyl ethers of polyhydric alcohols, and optionally(d) styrene.
摘要:
Suspension polymers having high swellability have low contents of soluble fractions if aliphatic peroxy esters are used as polymerization initiators.
摘要:
Monodisperse crosslinked polymers prepared by seed/feed polymerization have less tendency to tack when a microencapsulated monodisperse crosslinked polymer has been used as seed. Compared with the seed used, the seed/feed polymer obtained exhibits substantially less broadening of the particle size distribution when microencapsulated seed has been used.
摘要:
An improved aminomethylation process gives weakly-basic anion exchangers in an elegant way, with by-product obtained being able to be processed into a suitable starting material without problems.
摘要:
Methanol can be substantially removed from dimethyl carbonate (DMC)/methanol mixtures by absorption on ion exchange resins. The enriched DMC is obtained as filtrate. The absorption is carried out at from -50.degree. C. to +100.degree. C. and 0.1-10 bar.