Abstract: The new aromatic thermoplastic polyesters and polyester carbonates based on diphenols, dicarboxylic acids, chain terminators and, optionally, branching agents, which are characterized in that the chain terminators correspond to the following formula ##STR1## in which R.sub.1, R.sub.2 and R.sub.3 may be the same or different and represent C.sub.2 -C.sub.12 alkyl or C.sub.8 -C.sub.20 aralkyl and at least one of the substituents R.sub.1 or R.sub.2 is a C.sub.8 -C.sub.20 aralkyl radical andn has a value of 0.5 to 1,are suitable for the production of moldings, films, fibers and filaments. The polyesters and polyester carbonates are distinguished by good thermal stability.

Abstract: This invention relates to thermoplastic, aromatic polycarbonates prepared with the aid of chain terminating agents corresponding to formula (I) ##STR1## to a process for the preparation of these polycarbonates and to their use for the production of moulded articles for optical purposes.

Abstract: The reaction of--preferably partially crystalline--polyamides with monoisocyanate or monoisocyanate precursors gives products having improved flowability, mould release and/or notched impact strength.

Abstract: This invention relates to thermoplastically deformable, high molecular weight, slightly branched aliphatic polyamides prepared by the polycondensation of polyamide-forming, aliphatic diamine/dicarboxylic acid mixtures, optionally with the addition of lactams and special amino acids, in the presence of small quantities of .alpha.-amino-.epsilon.-caprolactam, and optionally their thermal solid phase after-condensation.

Abstract: Thermotropic, fully aromatic polyesters and polyester carbonates are produced by esterification of optionally substituted p-hydroxybenzoic acids and aromatic dicarboxylic acids with diaryl carbonate at temperatures in the range from 100.degree. to 220.degree. C. and subsequent transesterification of the aryl ester obtained with diphenols and, optinally, more diaryl carbonate, accompanied by polycondensation, at temperatures in the range from 250.degree. to 330.degree. C., the esterification, the transesterification and the polycondensation being carried out in the presence of heterocyclic compounds containing 1 to 3 nitrogen atoms.

Abstract: Thermotropic fully aromatic polyester carbonates containing condensed residues of optionally substituted 3-hydroxybenzoic acid have great rigidity, impact strength and elongation at break and yet can be processed under the usual conditions owing to their advantageous fusion viscosity.

Abstract: The invention relates to a process for the production of vinyl copolymers with grafted-on polycarbonate chains, to the grafted vinyl copolymers obtainable by the process according to the invention, to their use as modifiers for mixtures of thermoplastic polycarbonates and thermoplastic polystyrenes, to such mixtures themselves and to the use of such mixtures as substrates for optical discs.

Abstract: Thermoplastic, easily flowing hydrophobic polyamides obtained by incorporation of from 2 to 15% by weight, based on polyamide, of at least one monoepoxide compound corresponding to the following general formula ##STR1## in which R is a hydrocarbon radical containing at least 4 carbon atoms.

Abstract: This invention relates to a process for the preparation of high molecular weight, optionally branched polyarylenesulphides from alkali metal sulphides, optionally in admixture with alkali metal hydrogen sulphides and aromatic dihalogen compounds, in a polar solvent in the presence of from 0.1 to 6.0 mol-%, preferably from 0.25 to 4.0 mol-%, of an aromatic monoalkoxy or monoalkylthio compound. The polyarylenesulphides obtained have reproducibly adjustable melt viscosities and molecular weights and are distinguished by their reduced tendency to corrosion.

Abstract: Thermoplastically polyamide moulding compositions produced from at least 70% by weight of polyamide, a long-chain polyester, polyether or hydrocarbon polyol and at most 5% by weight of a polyanhydride or polyepoxide.

Abstract: A level control system for motor vehicles having pneumatic springs which function in accordance with the vehicle load. A specified distance is normally maintained between the vehicle body the vehicle axle. This distance is maintained by charging or discharging the pneumatic springs. The level control system includes an air dryer and a pneumatic relay type of controllable discharge valve having a relatively large cross-sectional port by which the air dryer is connected to the atmosphere. The discharge valve operates against a spring return force. The magnitude of the spring return force corresponds to a preselected minimum pneumatic spring pressure. The system counteracts an icing action of the discharge valve and prevents an unintentional and complete discharging of the pneumatic springs.

Abstract: Polyamide moulding materials which have been reinforced with unsized glass fibres and to which a flame-proof finish has been imparted by means of melamine or melamine cyanurate and which have a high glow wire resistance.

Abstract: This invention relates to a process for the preparation of optionally branched polyarylene sulphides which are distinguished by their substantially lower corrosiveness.

Abstract: Biuret-group-containing polyisocyanates based on non-aromatic diisocyanates, possibly mixed with liquid N-alkyl-lactams, as activators for activated anionic polymerization of lactams.

Abstract: Thermoplastically processable polyamide moulding compositions which are equipped with inorganic reinforcing materials and contain 3 to 40% by weight, relative to the amount of polyamide, of bisphenols of the formula (I) ##STR1## where R stands for CH.sub.3, CH.sub.3 O, C.sub.2 H.sub.5 group,m and n independently of each other denote whole numbers from 0 to 4 andX denotes a chemical bond, a C.sub.1 -C.sub.7 -alkylene or C.sub.5 -C.sub.6 -cycloalkylene radical, O, S, SO, SO.sub.2, CO or O--(CH.sub.2).sub.p --O-- with p=2 to 10and with the proviso that the sum of the aliphatic C atoms of all the radicals bonded to the phenol rings is <6.

Abstract: Cyclic amidines which are modified by the incorporation of additional polar groups, may be used as catalysts for hardening heat-curable resin compositions comprising polyepoxides and optionally carboxyl group-containing polymers. Such amidine catalysts yield a high reactivity, an excellent storage stability and result in elastic coatings which show a high gloss and a good resistance to solvents.

Abstract: Improved activators for anionic polymerization of lactams are biuret-containing polyisocyanates based on non-aromatic diisocyanates.

Abstract: Easily flowable, impact resistant polyamide moulding composition containing from 0.5 to 10%, by weight, of polyethers preferably modified with (meth)acrylate or primary amino end groups or of polyesters preferably containing (meth)acrylate end groups.

Abstract: In a therapeutic system such as a plaster for administration of an active compound through the skin and comprising a covering layer which is essentially impermeable to the active compound, an active compound reservoir layer and a protective layer which can be pulled off and which is essentially impermeable to the active compound, the improvement wherein the reservoir layer contain about 1-30% of active compound in an elastomer mixture comprising a predominantly amorphous olefinic (co)polymer with a glass transition temperature of <20.degree. C., mixed with from 0 up to about 50% by weight of a polyisobutylene, polybutadiene oil and/or paraffin oil, and a tackifying resin. Thereby the active compound can be released in regulated relatively large quantity over a prolonged period of time.

Abstract: In a therapeutic system such as a plaster for administration of an active compound through the skin and comprising a covering layer which is essentially impermeable to the active compound, an active coupound reservoir layer and a protective layer which can be pulled off and which is essentially impermeable to the active compound, the improvement wherein the reservoir layer contains about 1-30% of active compound in an elastomer mixture comprising a diene rubber which can optionally be copolymerized with an .alpha.-olefin, mixed with from 0 up to about 70% by weight of a polyisobutylene, polybutadiene oil and/or paraffin oil, and a tackifying resin. Thereby the active compound can be released in regulated relatively large quantity over a prolonged period of time.