Abstract: 3-Chloro-3'-nitro-4'-methoxybenzophenone with substantially lower contents of dinitro derivatives than hitherto is obtained if 3-chloro-4'-methoxybenzophenone is nitrated in from 65 to 85% strength by weight sulfuric acid with nitric acid at temperatures in the range from -20.degree. to +60.degree. C.

Abstract: Mixtures consisting essentially of cyclohexylbiphenyls, dicyclohexylbenzenes, phenylbicyclohexyls and tercyclohexyls are outstandingly suitable as heat transfer media. The mixtures can be prepared from biphenyl and cyclohexanol in the presence of bleaching earths and subsequent hydrogenation.

Abstract: Thermoplastic aromatic polycarbonates having average molecular weights Mw of at least 10,000 which contain bifunctional carbonate structural units corresponding formula (I) ##STR1## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4 independently of one another represent hydrogen, a C.sub.1-12 hydrocarbon, halogen,Y.sup.1, Y.sup.2, Y.sup.3 independently of one another represent hydrogen,C.sub.1-5 alkyl, a C.sub.6-12 hydrocarbon radical,at least two of the substituents Y.sup.1, Y.sup.2 and Y.sup.3 not being hydrogen and at least one of the substituents Y.sup.1, Y.sup.2 and Y.sup.3 being C.sub.1-5 alkyl,in quantities of from 100 to 1 mol-%, based on the total quantity of difunctional carbonate structural units in the polycarbonate.

Abstract: Thermoplastic aromatic polycarbonates having average molecular weights Mw of at least 10,000 which contain bifunctional carbonate structural units corresponding to formula (I) ##STR1## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently of one another represent hydrogen, a C.sub.1 -C.sub.12 hydrocarbon radical, halogen andR.sup.5, R.sup.6 and R.sup.7 represent hydrogen, iso-C.sub.3 -C.sub.5 -alkyl,one of the substituents R.sup.5, R.sup.6 or R.sup.7 not being hydrogen, in quantities of from 100 to 1 mol-%, based on the total quantity of difunctional carbonate structural units in the polycarbonate.

Abstract: Thermoplastic aromatic polycarbonates having average molecular weight Mw of at least 10,000 which contain bifunctional carbonate structural units corresponding to formula (I) ##STR1## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently of one another represent hydrogen, a C.sub.1 -C.sub.12 -hydrocarbon, halogen,m is 2 or 3 andX represents hydrogen or a C.sub.6 -C.sub.12 hydrocarbon, at least one substituent X being a C.sub.6 -C.sub.12 hydrocarbon radical,in quantities of from 100 to 1 mol-% based on the total quantity of difunctional carbonate structural units in the polycarbonate.

Abstract: Thermotropic aromatic polyesters which contain 3,3'-diphenyl-4,4'-dihydroxydiphenyl radicals as diphenol radicals can be processed by thermoplastic methods without decomposition, in spite of the high heat distortion resistance.

Abstract: 2,4-Dichloro-3-alkyl-6-nitrophenols are prepared by chlorinating, with chlorine in the presence of a catalyst, 1-alkyl-4-nitrobenzenes having a C.sub.2 -C.sub.8 -alkyl radical until the content of trichloroalkylnitrobenzenes is at least 60% by weight in the chlorination mixture, removing the catalyst from the chlorination mixture, then hydrolyzing the chlorination mixture, removing the precipitated reaction product, and treating it with an aqueous inorganic acid. The 2,4-dichloro-3-alkyl-6-nitrophenols are new.

Abstract: Fully aromatic polyesters which contain 3-phenyl-4,4'-dihydroxybenzophenone radicals and/or 3-phenyl-3',4-dihydroxybenzophenone radicals as condensed units possess high mechanical properties but can still be processed without difficulties by a thermolastic method.