Abstract: A process of free-radically initiated aqueous emulsion polymerization, in which monomers are polymerized in the presence of a N-oxyl radical and by means of special free-radical polymerization initiators at more than 100° C. and at pressures above the vapor pressure of the polymerization mixture.

Abstract: In the process and a correspondingly appropriate device for preparing homo- or copolymers of at least one of the, polymerizable monomers of the group consisting of styrene, butadiene, vinyl chloride, vinyl acetate, vinylidene chloride, alkyl (meth)acrylatc (meth)acrylic acid, (meth)acrylonitrile and (meth)acrylamide reaction is carried out at at least 40° C. in the presence of a dispersing auxiliary and of a free-radical polymerization initiator such that at least 85% by weight of the polymer is formed from these monomers.

Abstract: A process of free-radically initiated aqueous emulsion polymerization, in which polymerization is conducted in the presence of a stable N-oxyl radical and the diameter of the monomer droplets in disperse distribution in the aqueous medium is ≦500 nm.

Abstract: A process is described for reducing the residual monomer content in a liquid solution, mixture, melt, suspension or dispersion of a polymer by postpolymerization with addition of a redox initiator system at a reaction temperature appropriate to it and with an extremely short mixing time of the liquid system in the production reactor by metering—gradually, in portions or continuously—at least one of the redox initiator components required to initiate polymerization of the residual monomers over a period (metering time) which is from about 10 to 250 times the mixing time of the liquid system in said reactor.

Abstract: A process for preparing recyclable fiber composites, comprising bonding fibers with a polymeric bonding agent applied as an aqueous polymer dispersion to said fibers, the polymeric bonding agent comprising at least one addition polymer which, in the state of an aqueous dispersion, has a film forming capability at the temperature at which the addition polymer is combined with said fibers, and said aqueous polymer dispersion, when subjected to a change in pH, is converted into an aqueous solution of the addition polymer. The aqueous addition polymer of the addition polymer dispersion can contain protic acid groups, and the state of the dispersion can be converted to an aqueous addition polymer solution by raising the pH of the aqueous medium. Alternatively, the addition polymer may contain basic groups, in particular, amino groups, and its state as a dispersion can be converted into an aqueous addition polymer resolution by lowering the pH of the aqueous medium.

Abstract: A voltage comparator (10) includes two sampled input networks connected in arallel between an input reference voltage (Vref) and the inverting input (16) of an integrator (12,14), the other input (18) of which is grounded. The first input network has a first input capacitor (C1) which is through-switched at a first sampling frequency (F1). The second input network has a second input capacitor which is diagonally-switched at a second sampling frequency (F2), thus providing an output voltage to the integrator (12,14) which is of opposite polarity to that of the first network. For a given ratio between the capacitors (C1,C2), the output (15) of the integrator is determined by the relationship between the sampling frequencies (F1,F2), thus providing a comparator capability. Also disclosed is a frequency lock loop (34) in which the output (Vcontrol) of a frequency comparator (38) is filtered of the switching frequencies and utilized as the control voltage for a voltage controlled oscillator (42).

Abstract: A CMOS circuit (10) for preventing overvoltage between two supply nodes (12,14) makes use of vertical NPN bipolar transistors (80,84) for their current-carrying capability. Zener diodes (16,18,20,22) and a resistor (24) generate a sensing voltage which is amplified by a vertical bipolar transistor (28) and coupled to one input of a comparator (40) which has the other input at a bias voltage node (52) of a voltage divider (54,56,58,60). The comparator output (50) is coupled to the input of a transimpedance transistor (72) which drives the input current of a current mirror (66,74). The output (78) of the current mirror turns on the current-carrying transistors (80,84). Positive feedback for latching is provided by connecting the common gates of the current mirror transistors to the gate of a feedback transistor (86) which has its current path connected between the one supply node and the base (26) of the first bipolar transistor.