Abstract: The method for making the surface of a window or windshield of a vehicle hydrophilic improves visibility for the operator of the vehicle during rain or fog. The method includes exposing the window or windshield surface to a corona discharge from at least one moving electrode that passes over the surface, especially at least one electrode associated with the rubber wiper blade (22) of a wiper apparatus for the window or windshield. The degree of hydrophilization of the surface is controlled by adjusting the level and/or the frequency or the duration of the high-frequency alternating current voltage applied to the moving electrode to produce the corona discharge. Alternatively the degree of hydrophilization of the surface is controlled by adjusting the spacing (a) of the at least one electrode from the surface.

Abstract: Copolymers of ethylene containing not more than 4 moles, based on 100 moles of ethylene, of copolymerized C.sub.3 -C.sub.6 -alkenecarboxylic acids are prepared in a continuously operated tubular polymerization system under high pressures and temperatures in the presence of a polymerization initiator by a process in which a mixture of ethylene, the alkenecarboxylic acid, if required a further monomer which is copolymerizable with ethylene, an initiator and, if required, a regulator is fed into the polymerization system at its entrance and at the same time at a second point downstream of the entrance, along the polymerization system, where the reaction temperature has exceeded a maximum, the amount of alkenecarboxylic acid at the entrance of the polymerization system being not more than 0.3, preferably less than 0.28, mole, based on 100 moles of ethylene, and the remainder being metered in at the second feed point.

Abstract: Propylene/ethylene block copolymers are prepared by a process in which, in an agitated fixed bed comprising small polymer particles and in each case in the presence of hydrogen, first (I) propylene is homopolymerized from the gas phase, in a first polymerization zone, by feeding in a Ziegler-Natta catalyst, and then (II) the product obtained in the first polymerization zone is fed into a second polymerization zone, where a mixture of propylene and ethylene is polymerized with the propylene homopolymer present in the product from the first polymerization zone.