Abstract: A method is provided for continuous mass polymerization of acrylonitrile-butadiene-styrene type thermoplastics. The method involves charging a liquid feed comprising a vinylidene aromatic monomer, an unsaturated vinyl nitrile monomer and a synthetic butadiene polymer dissolved therein into a grafting reactor to prereact the liquid mass to form grafted rubber continuous phase polymeric product. The product from the grafting reactor is then charged to a phase inversion reactor where free rigid copolymer in monomer is the only continuous phase, and where dispersed particles of grafted rubber with occluded rigid copolymer and monomer are immediately formed from the product of the grafting reactor. The second polymerization product, which is coming out from the phase inversion reactor, is then charged to a finishing reactor wherein the material is further polymerized to form a third polymerization product which then can be devolatilized to provide a final thermoplastic composition.

Abstract: A method is provided for continuous mass polymerization of acrylonitrile-butadiene-styrene type thermoplastics. The method involves charging a liquid feed comprising a vinylidene aromatic monomer, an unsaturated vinyl nitrile monomer and a synthetic butadiene polymer dissolved therein into a grafting reactor to prereact the liquid mass to form grafted rubber continuous phase polymeric product. The product from the grafting reactor is then charged to a phase inversion reactor where free rigid copolymer in monomer is the only continuous phase, and where dispersed particles of grafted rubber with occluded rigid copolymer and monomer are immediately formed from the product of the grafting reactor. The second polymerization product, which is coming out from the phase inversion reactor, is then charged to a finishing reactor wherein the material is further polymerized to form a third polymerization product which then can be devolatilized to provide a final thermoplastic composition.

Abstract: A bulk or mass polymerization process is provided which involves bulk polymerization of vinyl monomers in a liquid phase in the presence of a nitrogen rich vapor phase containing amounts of sulfur dioxide effective to inhibit formation of popcorn polymer during the reaction. The process may be used as a step in the formation of polymer or may be used as the entire reaction process.

Abstract: A terpolymer of a monovinylic aromatic monomer, an acrylic monomer and maleic anhydride is formed according to a polymerization method in which the maleic anhydride is added to the reactor in a molten state, free of solvents and diluents, and the polymerization reaction is conducted in bulk in the absence of solvents and diluents. The terpolymer is useful in various applications including blending with ABS graft polymers.

Abstract: A hydraulic elevator system which utilizes a single hydraulic jack having a cylinder fixed below an elevator car, and a plunger. The elevator car is supported on the end of the plunger. The hydraulic jack extends upwardly and into the elevator car, reducing the space required below the car by the amount of the penetration of the hydraulic jack. The hydraulic jack is disposed adjacent to the front portion of the hatchway, enabling it to occupy an enclosed, concealed space in the elevator car, between its entranceway and its operational controls.