摘要:
Polytetrahydrofuran, copolymers of tetrahydrofuran and 2-butyne-1,4-diol, diesters of these polymers with C.sub.2 -C.sub.20 -monocarboxylic acids or monoesters of these polymers with C.sub.1 -C.sub.10 -monocarboxylic acids are prepared by polymerization of tetrahydrofuran in the presence of one of the telogens water, 1,4-butanediol, 2-butyne-1,4-diol, polytetrahydrofuran having a molecular weight of from 200 to 700 Dalton, a C.sub.1 -C.sub.10 -monocarboxylic acid or an anhydride of a C.sub.2 -C.sub.20 -monocarboxylic acid or a mixture of these telogens over a heterogeneous supported catalyst which comprises a catalytically active amount of an oxygen-containing molybdenum and/or tungsten compound on an oxidic support material and which has been calcined at from 5OO.degree. C. to 1OOO.degree. C. after application of the precursor compounds of the oxygen-containing molybdenum and/or tungsten compounds onto the support material precursor, wherein the catalyst is activated by treatment with a reducing agent before it is used as a polymerization catalyst.
摘要:
N-Substituted cyclic amines are prepared by reacting diols with primary amines over a copper-containing catalyst which is obtainable by impregnation of an inert support with an aqueous solution of an ammine complex of a readily thermally decomposable copper compound and subsequent drying and calcination and contains from 5 to 50% by weight of copper, calculated as CuO.
摘要:
In a process for preparing 1,3,5-tris(2-hydroxyalkyl) isocyanurates from cyanuric acid and aliphatic epoxides, the reaction is carried out in the presence of catalytic amounts of an organic phosphorus compound.
摘要:
Polytetrahydrofuran or polytetrahydrofuran monoesters of C.sub.1 -C.sub.20 -monocarboxylic acids or polytetrahydrofuran monoethers of monohydric C.sub.1 -C.sub.20 -alcohols, having an average molecular weight of from 250 to 10,000 Dalton and liquid at room temperature, are prepared by the cationic polymerization of tetrahydrofuran in the presence of a telogen by a process in which tetrahydrofuran is polymerized in the presence of water, 1,4-butanediol and/or polytetrahydrofuran having an average molecular weight of from 200 to 700 Dalton and/or of a C.sub.1 -C.sub.20 -monocarboxylic acid and/or of a monohydric C.sub.1 -C.sub.20 -alcohol with the aid of a catalytic amount of a zeolite catalyst which has an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of from 4:1 to 100:1 and in which the population ratio P of the acid centers on the external surface of the zeolite to the total number of acid centers of the zeolite is 0.03/l or more.
摘要:
Polytetrahydrofuran or C.sub.2 -C.sub.10 -alkylene oxide/tetrahydrofuran copolymers having a molecular weight of from 250 to 20,000 Dalton are prepared by the cationic polymerization of tetrahydrofuran or tetrahydrofuran and C.sub.2 -C.sub.10 -alkylene oxides in the prsence of a promoter by a process in which the catalyst used is a mixture of one or more C.sub.2 -C.sub.6 -di- or tricarboxylic acids with boric acid.
摘要:
A device is suggested which serves to lock and unlock closed doors of a motor vehicle. The device comprises a lock which is assigned to every door, can be actuated with a key and whose locking element is swivelably supported at the door and whose retainers, which cooperate with the latter, are arranged near the door opening so as to be fixed with respect to the body of the vehicle. The locking element is a structural component part which is spring-loaded relative to the unlocking position and engages behind the pin-like retainers with a hook-shaped projection in its locking position. The locking element has two catches which together enclose an angle with reference to the swivel axis of the locking element, which catches cooperate with counter-catches of a swivelable latch element which are spring-loaded relative to the catch position. To actuate a device constructed in such a way by motor as well, the lock has an actuating element which can be activated by motor, swivels the locking element into its locking position for locking the door and moves the latch element against the spring force for unlocking door and in so doing disengages the catches and counter-catches.
摘要:
Polymers having terminal halogen atoms and consisting of cationically polymerizable, olefinically unsaturated monomers are obtainable by polymerization using an initiator system comprising a halogen-containing Lewis acid and a 3-membered to 8-membered cyclic ether.
摘要:
Unsaturated nitriles of the general formula I ##STR1## where R is a branched or straight-chain alkyl radical of 4 to 10 carbon atoms or a phenyl ring which is substituted by alkyl of 1 to 4 carbon atoms, one or more alkoxy groups of 1 to 3 carbon atoms, preferably 1 or 2 methoxy groups, or alkylenedioxy, preferably methylenedioxy, and their preparation and their use as scents.
摘要:
Cycloalkylidene derivatives of the general formulae Ia to Ic ##STR1## where the dashed line is a possible additional chemical bond, the radicals R.sup.1 are identical or different C.sub.1 -C.sub.4 -alkenyl groups, R.sup.2 and R.sup.3 are each methyl or ethyl, R.sup.4 is hydrogen or one of the radicals R.sup.1, X is oxygen, methylene or a chemical bond, m is from 0 to 3 or, when X is methylene, is from 1 to 3, or, when X is methylene and R.sup.1 is methyl, is from 2 to 3 and n is from 0 to 3, are used as fragrance materials.
摘要:
The quality of Robusta coffee is increased by treating raw Robusta coffee beans whose water content has been increased to about 30% to 45% with steam at about 135.degree. C. to 140.degree. C. and at a pressure ranging from 3 bar to 4 bar approx. for 60 min to 120 min. This treatment particularly removes the substance responsible for the "earthy" and "musty" aroma note of Robusta coffee, namely the compound 2-methylisoborneol. After the treatment, the beans are processed and roasted in the customary way.