Abstract: Salts of lower alkyl vinyl ether/maleic anhydride are described as active components in dental adhesives. A process for the preparation of these salts is described.The salts are partially neutralized mixed salts of lower alkyl vinyl ether/maleic anhydride copolymers. The neutralization of the copolymer is effected with aluminum, and calcium and/or sodium.

Abstract: The present invention relates to a novel process for the production of low viscosity copolymers of maleic acid monoalkyl ester and vinyl alkyl ethers characterized in that the copolymerization of alkyl vinyl ether is performed with a mixture composed of maleic acid anhydride and maleic acid monoalkyl ester. The specific viscosity is controlled by the setting of a certain maleic acid anhydride to maleic acid monoalkyl ester ratio.

Abstract: A process of manufacturing powdered copolymers of maleic anhydride with methyl vinyl ether in a mole ratio of 1:1 and a specific viscosity in a range from 2 to 5 by copolymerization of maleic anhydride with methyl vinyl ether in the presence of radical initiators to initiate polymerization. The process includes mixing maleic anhydride with an excess of about 3 to about 20 mol methyl vinyl ether per mol maleic anhydride and initiating a polymerization reaction with a radical initiator added in a quantity of from about 0.001 to about 1 weight % with respect to the maleic anhydride. The polymerization reaction takes place in the absence of other solvents.

Abstract: A valve for controlling the flow of dangerous fluids includes a housing having a housing member equipped with connecting nipples and with a valve seat formed on a discrete seat member, a magnet-supporting socket connected to the housing member and bounding a compartment therewith, and a valve member accommodated in the compartment and displaceable toward and away from the seat to control the flow of the fluid through the compartment between the connecting nipples. A layer of corrosion-resistant material is explosion welded to and covers the internal surface of the housing. The magnet-supporting socket includes two components of materials which are incapable of being welded to one another in a melt-welding operation, the components being connected to one another by explosion-welding.