Abstract: Thermoplastic materials which comprise a copolymer of(A) 16 to 40 wt % of acrylic and/or methacrylic acid;(B) 30 to 80 wt % of methyl acrylate; and(C) 0 to 40 wt % of another alkyl ester of acrylic and/or methacrylic acid and perhaps conventional auxiliaries for drug coatings are suitable for the production of drug coatings which are soluble in intestinal juices, such as tablet coatings, dies, films, capsules, or multipart dosage units.

Abstract: A plastic melt is treated for a short-time with a liquid treatment agent under pressure, it is divided into defined subquantities, individual subquantities are brought into contact with a treatment agent and combined for a residence time of less than one second with portions of at least one other subquantity, and portions of the mixture thus formed are separated and combined with another subquantity; the steps of dividing and combining the mixture are repeated several times at intervals of less than one second until an intimate mixture of the plastic melt and the treatment agent has formed, allowing the preparation of especially homogeneously structured thermoplastic materials, e.g., poly(methacrylalkylimide) plastics, which are compatible with poly(methyl methacrylate).

Abstract: Homogeneous polymer mixtures of polymethacrylimides consist of a component (A), composed of from 30 to 90 percent by weight of methacrylalkylimide units and from 3.5 to 10 percent by weight of methacrylic acid units, and of a component (B1) or (B2) having from 10 to 50 percent by weight more methacrylalkylimide units than component (A), component (B1) having a degree of imidization of less than 95 percent and containing from 3.5 to 10 percent by weight of methacrylic acid units, and component (B2) having a degree of imidization greater than 95 percent and containing less than 3.5 percent by weight of methacrylic acid units.

Abstract: In a process for imidizing an alkyl methacrylate polymer by reaction with a nitrogen-containing imidizing agent, the formation of carboxyl and anhydride groups is suppressed when a portion of the imidizing agent is added only after the previously added imidizing agent has been reacted at least partially, and particularly when the reaction with the imidizing agent is terminated before the polymer has been completely imidized.

Abstract: Injection molded parts having a scratch resistant surface are produced by applying a liquid mixture of at least one monomer susceptible of free radical polymerization and having more than one polymerizable double bond and of at least one free radical forming initiator to the forming surface of an injection mold, polymerizing the mixture at least partially, and then injecting a thermoplastic or duroplastic molding composition into the closed mold.