Abstract: Disclosed is an improved weatherable thermoplastic composition. The composition is comprised of a copolymer of an alkyl acrylate or alkyl methacrylate and poly(methyl)methacrylate and a multi-stage, sequentially-polymerized impact modifier polymer. The copolymer is characterized by greater than 15 weight percent alkyl acrylate content. The multi-stage, sequentially-polymerized impact modifier is characterized by an elastomer stage, which is 55 percent by weight or greater of the impact modifier composition and is minimally crosslinked. The thermoplastic composition can be used in a wide range of film, sheet, or molded applications.

Abstract: A composition, particularly suited for forming a surface layer (capstock) with excellent weathering properties of a composite which includes an underlaying layer of PVC or other structural plastic, is comprised of vinyl chloride polymer, an organotin maleate and an acrylic blend of an acylic monomer or copolymer resin and an acrylic weatherable impact modifier.

Abstract: The present invention is directed to methacrylic polymer compositions which may be used to form plastic products which have increased resistance to discoloration by sterilizing radiation, such as gamma or electron beam irradiation. The compositions, free from conventional ultraviolet stabilizers, contain .alpha.-hydroxyacids or esters thereof.

Abstract: Plastics prepared from blends of polymers of methyl methacrylate with heterogeneous core/shell polymers having an poly(alkyl acrylate) core and a poly(alkyl methacrylate)shell exhibit improved color when the heterogeneous core/shell polymer is treated with a reducing agent.

Abstract: A quantitative, sensitive method for monitoring low concentrations of isothiazolones in aqueous systems is provided. The method involves the adsorption of the isothiazolones on a suitable adsorbent, the desorption of the adsorbed isothiazolones, the breaking of the isothiazolone ring and the formation of a blue complex by the reaction of the broken isothiazolone ring with ferric chloride and potassium ferricyanide. The concentration of the isothiazolones is then determined by conventional colorimetric techniques.