Abstract:
A compatibilized thermoplastic molding composition containing polyurethane and polyolefin resins is disclosed. Accordingly, a particularly structured copolymer having a number average molecular weight of about 25,000 to 350,000 and containing blocks of monoalkylene arene and either hydrogenated conjugated diene or non-hydrogenated conjugated diene, was found to compatibilize the composition. Articles molded from the composition are characterized by their good mechanical properties.
Abstract:
A substantially linear poly-vinylarene/polyurethane block copolymer prepared by reacting (1) a difunctional poly-vinylarene which is produced by anionic polymerization and which contains isocyanate-reactive groups, (2) a diisocyanate or an isocyanate prepolymer, and (3) a diol having a high molecular weight or a chain extender having a lower molecular weight, is disclosed to be suitable for the preparation of shaped articles, coatings, coupling agents and compatibilizers.
Abstract:
The present invention is directed to poly-.alpha.-olefin/polyurethane block copolymers which are prepared by reactingA) isocyanate-reactive functionalized poly-(C.sub.2 -C.sub.10 -.alpha.-olefins) having a number average molecular weight M.sub.w of about 1000 to 350,000,B) polyisocyanates, isocyanate prepolymers or modified polyisocyanates, and, optionally,C) isocyanate-reactive synthesis units containing Zerewitinoff-active hydrogen atoms and having a molecular weight of 400 to about 5000 and, optionally,D) low molecular weight isocyanate-reactive chain extending agents having a molecular weight of 32 to 399.The present invention is also directed to this process for preparing the poly-.alpha.-olefin/polyurethane block copolymers and to their use as polymer dispersants for the production of polymer blends, as primers or modifiers or for the production of moldings or coatings.
Abstract:
The present invention is directed to aqueous solutions or dispersions of cationically modified polyurethanes, characterized in that the dissolved or dispersed polyurethanes(i) contain about 2 to 200 milliequivalents of incorporated ammonium groups per 100 g of solids content,(ii) contain 0 to about 25% by weight of ethylene oxide units within terminal or lateral polyether chains and(iii) contain at least 1.3% by weight, calculated as SiO.sub.3 (molecular weight=76), of built-in structural units corresponding to the formula ##STR1## wherein R', R" and R"' may be the same or different and represent hydrogen or alkyl groups containing 1 to 4 carbon atoms,the total quantity of hydrophilic structural units (i) and (ii) being sufficient to ensure the solubility or dispersibility of the polyurethanes in water and the solutions or dispersions having a pH value of 3 to 6. The present invention is also directed to a process for the preparation of these storage stable aqueous solutions or dispersions and to their use as coating compounds or for the preparation of coating compositions for any substrates.
Abstract:
The present invention is directed to polyethers obtained by the reaction of a substituted 1,2-epoxy-alkane bearing at least one alkyl substituent containing at least 8 carbon atoms with at least one polyol corresponding to the formulaR(OH).sub.x (1)whereinR is an organic radical andx is an integer having a value of 2 or more,2 or more moles of epoxyalkane being added onto the polyol (1).The present invention is also directed to a process for the preparation of high molecular weight polymers wherein the process is conducted in the presence of the previously described polyethers as a mold release agent.
Abstract:
A method of controlling a spot welding system used for attaching an inserted element in a hollow member is provided. A position of the inserted element in the hollow member is determined, the position of an attachment point is determined from the position of the inserted element in the hollow member, and a spot welding operation is performed at the attachment point. Further, a spot welding system for carrying out the method is provided.
Abstract:
A method for operating a continuous flow steam generator with an evaporator heating surface is provided. A target value for a supply water mass flow is fed to a device for adjusting the supply water mass flow. In order to improve the quality of a predictive supply water or mass flow control and to maintain the enthalpy of the flow medium at the evaporator outlet particularly stable especially when load changes occur, a correction factor is taken into consideration during production of the target value for the supply water mass flow. The correction factor is a characteristic of the temporal derivative of enthalpy or the density of the flow medium at the input of one or more heating surfaces.
Abstract:
A continuous evaporator for a horizontal waste heat steam generator is provided. The continuous evaporator includes a first evaporator heating surface that has a number of essentially vertically arranged first steam generating tubes wherein the circulation takes place from the bottom to the top, and another second evaporator heating surface located downstream of the first evaporator heating surface on the side of the flow medium, the second evaporator heating surface including a number of other essentially vertically arranged second steam generating tubes wherein the circulation takes place from the bottom to the top is provided. In order to provide a continuous evaporator with an especially simple structure and an especially long service life, a number of second steam generator tubes have an inner profiled element.
Abstract:
A continuous evaporator for a horizontally constructed waste heat steam generator is provided. The continuous evaporator includes a first evaporator heating surface having a plurality of essentially vertically arranged first steam generator tubes through which a flow medium may flow from bottom to top, and another second evaporator heating surface which is mounted downstream of the first evaporator heating surface on the flow medium side. The second evaporator heating surface includes a plurality of additional essentially vertically arranged second steam generator tubes through which a flow medium may flow from bottom to top. An aperature system is arranged downstream of the second steam generator tubes on the flow medium side.
Abstract:
A continuous steam generator is provided. The continuous steam generator includes a combustion chamber having a number of burners for fossil fuels, downstream of which a vertical gas duct is mounted, on the hot gas side, in an upper region above a horizontal gas duct. The outside wall of the combustion chamber is formed, in a lower region, from evaporation tubes welded together in a gas-tight manner and mounted upstream of a water separator system, on the flow medium side, and in an upper region, from superheater tubes welded together in a gastight manner and mounted downstream of the water separator system on the flow medium side. The boundary between the regions of the evaporation tubes and the superheater tubes is essentially horizontal around the combustion chamber, in a region of the bottom of the horizontal gas duct.