Abstract: High-functionality polyisocyanates are prepared by a process which comprises (i) preparation of an addition product (A) which contains one group which is reactive toward isocyanate and at least two isocyanate groups by reacting (a) a diisocyanate or polyisocyanate I with (b1) compounds having at least three groups which are reactive toward isocyanate or (b2) compounds containing two groups which are reactive toward isocyanate or mixtures of (b1) and (b2), where at least one of the components (a) or (b) has functional groups having differing reactivities toward the functional groups of the other component and the reaction ratio is selected so that the addition product (A) contains an average of one group which is reactive toward isocyanate, (ii) if desired, intermolecular addition reaction of the addition product (A) to form a polyaddition product (P) containing an average of one group which is reactive toward isocyanate and an average of more than two isocyanate groups, and (iii) reaction of the addition

Abstract: Polyisocyanates are prepared by a process which comprises (i) preparation of an addition product (A) which contains one group which is reactive toward isocyanate and one isocyanate group by reacting (a) a diisocyanate I with (b) compounds containing two groups which are reactive toward isocyanate, where at least one of the components (a) or (b) has functional groups having differing reactivities toward the functional groups of the other component, (ii) if desired, intermolecular addition reaction of the addition product (A) to form a polyaddition product (P) which contains one group which is reactive toward isocyanate and one isocyanate group and (iii) reaction of the addition product (A) and/or the polyaddition product (P) with a diisocyanate or polyisocyanate II which is different from diisocyanate I.

Abstract: Propylene/ethylene block copolymers are prepared by a continuous process in which, in each case in an agitated fixed bed of finely divided polymer from the gas phase, first (I) in a first polymerization zone, propylene is homopolymerized by feeding in a Ziegler-Natta catalyst system consisting of (1) a titanium component which contains titanium, magnesium, chlorine and a phthalic acid derivative, (2) an aluminumalkyl component and (3) a silane component, and (II) in a second polymerization zone, a mixture of propylene and ethylene is polymerized with the propylene homopolymer present in the reaction mixture obtained in the first polymerization zone by feeding in the said reaction mixture. In the process, (A) a titanium component (1) is used which is obtained by a method in which (1.1) first, (1.1.1) in a liquid hydrocarbon, (1.1.2) a finely divided magnesium halide, (1.1.3) an alkanol, (1.1.4) a certain phthalic acid derivative and (1.1.

Abstract: A catalyst for the copolymerization of ethylene by the gas-phase fluidized-bed method is prepared by a process in which a titanium-containing and magnesium-containing active component, reacted with an alcohol as a complexing agent, is applied to a finely divided silica from homogeneous solution, in the presence of a polysiloxane, by evaporating the solvent, and the resulting homogeneous catalyst intermediate is then preactivated by treatment with the alkylaluminum compound and the Lewis base in an inert hydrocarbon solution, and the copolymers prepared using the above catalyst are employed for the production of films exhibiting little blocking.

Abstract: Finely divided ethane polymers are prepared using a Ziegler catalyst system consisting of (1) a titanium-containing catalyst component which has been obtained by (1.1) precipitation in an organic liquid comprising (1.1.1) a solution of titanium tetrachloride in a hydrocarbon, (1.1.2) a solution of a certain organoaluminum compound in a hydrocarbon and (1.1.3) an alpha-monoalkene, and (2) an aluminum-containing catalyst component. In this process, the component (1) used is a component where (1.

Abstract: Ethene homopolymers and ethene copolymers with minor amounts of higher .alpha.-monoolefins are prepared by polymerization of the monomer or monomers using a chromium trioxide catalyst which is obtained by a method in which (1) a finely divided, porous, silicate carrier is laden with (2) chromium trioxide or a chromium compound which is converted to chromium trioxide under the conditions of stage (3), and then (3) the intermediate resulting from stage (2) is heated in an oxygen-containing gas stream. In this process, a cocatalyst which consists of a lithiumalkyl used in addition to the chromium trioxide catalyst.

Abstract: Ethene polymerization by Phillips catalysis is carried out using (1) a supported catalyst, which is laden with chromium, phosphorus and aluminum, and (2) a cocatalyst, (1) being obtained by a method in which (1.1) a catalyst intermediate laden with chromium, phosphorus and aluminum is prepared from a silicate carrier, a selected chromium compound, a selected phosphorus compound and a selected aluminum compound, and then (1.2) the catalyst intermediate is heated in an oxygen-containing gas stream. In this process, the component (1) used is one which is obtained by a method in which, in each case in a specific manner, (1.1) in a first stage, (1.1.1) first a suspension is prepared from (1.1.1.1) a finely divided silicate carrier and (1.1.1.2) an inert organic solvent, (1.1.2) then, (1.1.2.1) in an inert organic solvent, (1.1.2.2) an organic chromium compound is combined with (1.1.2.3) an aluminum trialkyl, (1.1.3) then (1.1.3.1) the suspension resulting from (1.1.1) is combined with (1.1.3.

Abstract: A process for the continuous preparation of finely divided homopolymers and copolymers of ethene by catalytic polymerization in a circular tube reactor using a liquid alkane as reaction medium in which the ethene or ethene/comonomer mixture to be polymerized is present in dissolved form and the polymer formed is present in suspended form and running the reaction mixture as a cycle stream to which the feed materials are added by bleeding in and from which the polymer formed is withdrawn by bleeding out reaction mixture, comprising (a) maintaining the mean concentration C.sub.m of polymer in the cycle stream at a value within a certain range and (b) effecting the bleeding out of reaction mixture at a point of the cycle stream at which the concentration of polymer has a value which is lower than the mean concentration C.sub.m by a distinct and definite amount.

Abstract: Acrylates or methacrylates I ##STR1## (A and B=C.sub.2 -C.sub.5 -alkylene, R.sup.1 =H, CH.sub.3) are prepared by reacting an acrylate or methacrylate II ##STR2## (R.sup.2 =C.sub.1 -C.sub.4 -alkyl) with a heterocycle III ##STR3## in the presence of titanium alcoholates chelate compounds of the metals titanium, zirconium, iron and zinc with 1,3-dicarbonyl compounds.

Abstract: Ethane polymers are prepared by Phillips catalysis using (1) a supported catalyst which is laden with chromium, phosphorus and titanium and (2) a cocatalyst, (1) being obtained by a procedure in which (1.1) a catalyst intermediate laden with chromium, phosphorus and titanium is prepared from a silicate carrier, a selected chromium compound, a selected phosphorus compound and a selected titanium compound, and (1.2) the catalyst intermediate is then heated in an oxygen-containing gas stream. In the process, the supported catalyst (1) used is one which is obtained (using specific methods and substances in each case) by a procedure in which (1.1) in a first stage (1.1.1), a suspension is first prepared from (1.1.1.1) a finely divided silicate carrier and (1.1.1.2) an inert organic solvent, (1.1.2) a suspension is then prepared from (1.1.2.1) a finely divided chromium trioxide and (1.1.2.2) an inert organic solvent, (1.1.3) thereafter (1.1.3.1) the suspension resulting from (1.1.2) is combined with (1.1.3.

Abstract: A process for the preparation of aqueous polymer dispersions which have a low film-forming temperature but still give films having a high block resistance, and the use of these polymer dispersions as binders for coating materials.

Abstract: Aqueous polyacrylate dispersions having improved flow characteristics are prepared by polymerizing esters of acrylic acid and/or methacrylic acid and alkanols of 1 to 10 carbon atoms, with or without admixture of styrene and/or vinyl esters and/or water-soluble monoolefinically unsaturated comonomers (the monomer feed being in the form of an emulsion), in aqueous emulsion in the presence of a free radical polymerization initiator, a protective colloid, a nonionic emulsifier and a regulator, at least a part of the protective colloid being introduced into an aqueous initial charge, and a water-soluble regulator being employed in the initial charge and in the feed.