摘要:
A process for the preparation of alkoxycarboxylic acid esters of the general formula I ##STR1## in which Y denotes CR.sup.4 R.sup.5 or CR.sup.4 R.sup.5 -CR.sup.6 R.sup.7,R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8 denote C.sub.1 -C.sub.20 alkyl, C.sub.3 -C.sub.8 cycloalkyl, aryl, C.sub.7 -C.sub.20 aralkyl, and C.sub.7 -C.sub.20 alkylaryl andR.sup.2, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8 can additionally denote hydrogen, and n is 0 or 1,by the reaction of hydroxycarboxylic acid esters of the general formula II ##STR2## in which R.sup.2, R.sup.3, R.sup.8, Y, and n have the aforementioned meanings, with alcohols of the general formula IIIR.sub.1 --OH (III),in which R.sup.1 has the aforementioned meanings, in the presence of heterogeneous catalysts at temperatures ranging from 100.degree. to 400.degree. C. and pressures ranging from 0.01 to 150 bar, wherein the heterogeneous catalysts used are zeolites and/or hydrothermally prepared phosphates.
摘要:
A process for preparing halogen-free, reactive polyisobutene having a terminal double bond content of more than 50 mol % and an average molecular weight Mn of 280-10000 dalton by the cationic polymerization in the liquid phase of isobutene or hydrocarbon mixtures comprising isobutene comprises polymerizing at from −30° C. to +40° C. in the presence of a heterogeneous polymerisation catalyst comprising one or more oxides of the elements of transition groups V and VI of the Periodic Table of the Elements or in the presence of a heterogeneous polymerization catalyst comprising one or more oxidic compounds of one or more elements of transition groups V and VI of the Periodic Table of the Elements supported on a non-zeolitic oxidic support material which is not an oxygen-containing zirconium compound, the catalyst not containing a technically effective amount of halogen.
摘要:
In a process for preparing polytetrahydrofuran, polytetrahydrofuran copolymers or diesters or monoesters thereof by polymerization of tetrahydrofuran in the presence of at least one telogen and/or comonomer over acid-activated montmorillonite catalysts, the montmorillonite catalyst after acid activation has a ratio of montmorillonite structure to the sum of muscovite and kaolin structures, determined from the intensities of the reflections at 2&thgr;=5.5° for montmorillonite, 2&thgr;=9.0° for muscovite and 2&thgr;=12.5° for kaolin measured in the X-ray powder pattern, of at least 5:1.
摘要:
A process for decolorizing polymers or copolymers which are obtained by cationic polymerization of tetrahydrofuran or of tetrahydrofuran and alkylene oxide, in the presence or absence of a telogen, comprises a) first, if desired, removing the low-boiling components by vacuum distillation or extraction and b) heating the remaining polymer or copolymer in the presence of at least one auxiliary selected from the group consisting of solid oxides and/or sheet silicates to from 20 to 150° C.
摘要:
The invention relates to a method for producing polytetrahydrofuran, polytetrahydrofuran copolymers, diesters or monoesters of these polymers by polymerization of tetrahydrofuran in the presence of at least one telogene and/or comonomer on a sulfate-containing heterogeneous supported catalyst. A sulfate-containing heterogeneous supported catalyst is used containing at least one metal sulfate, metal hydrogen sulfate, metal oxide sulfate or mixtures thereof.
摘要:
In a process for the preparation of copolymers of tetrahydrofuran and but-2-yne-1,4-diol by catalytic polymerization of tetrahydrofuran, the polymerization is carried out over a heterogeneous acidic catalyst which has acid centers of acidity pK.sub.a
摘要:
Amines of the general formula I ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 : are each hydrogen, C.sub.1 -C.sub.20 -alkyl, C.sub.2 -C.sub.20 -alkenyl, C.sub.2 -C.sub.20 -alkynyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.4 -C.sub.20 -alkylcycloalkyl, C.sub.4 -C.sub.20 -cycloalkylalkyl, aryl, C.sub.7 -C.sub.20 -alkylaryl or C.sub.7 -C.sub.20 -aralkyl,R.sub.1 and R.sup.2 together are a saturated or unsaturated C.sub.3 -C.sub.9 -alkylene chain andR.sup.3 or R.sup.5 is C.sub.21 -C.sub.200 -alkyl or C.sub.21 -C.sub.200 -alkenyl or R.sup.3 and R.sup.5 together are a C.sub.2 -C.sub.12 -alkylene chain,are prepared by reacting an olefin of the general formula II ##STR2## where R.sup.3, R.sup.4, R.sup.5 and R.sup.6 have the abovementioned meanings, with ammonia or a primary or secondary amine of the general formula III ##STR3## where R.sup.1 and R.sup.2 have the abovementioned meanings, at from 200.degree.0 to 350.degree. C. and from 100 to 300 bar in the presence of a heterogeneous catalyst, wherein the heterogeneous catalyst used is an NU-85 zeolite.
摘要:
Amines of general formula I ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are each hydrogen, C.sub.1 -C.sub.20 -alkyl, C.sub.2 -C.sub.20 -alkenyl, C.sub.2 -C.sub.20 -alkynyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.4 -C.sub.20 -alkylcycloalkyl, C.sub.4 -C.sub.20 -cycloalkylalkyl, aryl, C.sub.7 -C.sub.20 -alkylaryl or C.sub.7 -C.sub.20 -aralkyl, R.sup.1 and R.sup.2 together form a saturated or unsaturated C.sub.3 -C.sub.9 -alkylene chain and R.sup.3 or R.sup.5 is C.sub.21 -C.sub.200 -alkyl or C.sub.21 -C.sub.200 -alkenyl, or R.sup.3 and R.sup.5 together form a C.sub.2 -C.sub.12 -alkylene chain, are prepared by reacting an olefin of the general formula II ##STR2## where R.sup.3, R.sup.4, R.sup.5 and R.sup.6 have the above-mentioned meanings, with ammonia or primary or secondary amines of the general formula III ##STR3## where R.sup.1 and R.sup.2 have the abovementioned meanings, at from 200.degree. to 350.degree. C. and from 100 to 300 bar in the presence of a heterogeneous catalyst, by a process in which the heterogeneous catalyst used is an oxide of group IVB or VIB or a mixture thereof on a carrier.
摘要:
A process for preparing &bgr;-alkoxynitriles by reacting &agr;,&bgr;-unsaturated nitriles with monohydric, dihydric or trihydric alcohols in the presence of basic catalysts at from −20 to +200° C. comprises using a diazabicycloalkene catalyst of the formula I where from 1 to 4 hydrogen atoms may be independently replaced by the radicals R1 to R4, in which case R1, R2, R3, R4 are each C1-20-alkyl, C6-20-aryl or C7-20-arylalkyl, and n and m are each an integer from 1 to 6.
摘要:
A process for working up at least partially deactivated polymerization catalysts for the polymerization or copolymerization of THF which are contaminated with the products of the polymerization or copolymerization of THF comprises (a) in a first step, cleaning the polymerization catalyst by treatment with steam at from 80 to 250° C. and a pressure of from 0.5 to 40 bar and, preferably, (b) in a second step, regenerating the clean polymerization catalyst.