COMPOSICION DE PLASTISOL

UN COMPUESTO DE PLASTISOL A BASE DE COPOLIMEROS DE ESTIROL, PLASTIFICANTES Y SUBSTANCIAS DE RELLENO INORGANICAS, CONTIENE COMO COPOLIMEROS DE ESTIROL COPOLIMEROS OBTENIBLES MEDIANTE POLIMERIZACION POR EMULSION, LOS CUALES CONTIENEN A) ESTIROL Y/O O (REFERIDO AL COPOLIMERO) DE ACIDO METACRILICO Y/O ACIDO ACRILICO Y/O ACIDO ITACONICO. PARA AUMENTAR LA RESISTENCIA A LA FRICCION SE PUEDEN AÑADIR OTROS RETICULANTES O REFORZADORES. LOS PLASTISOLES SON APROPIADOS EN LA CONSTRUCCION DE VEHICULOS COMO AGENTE PROTECTOR DE BAJOS, COMO ADHESIVO PARA EL REVESTIMIENTO INFERIOR DEL CAPO, COMO MASA PARA LA PROTECCION DE LOS UMBRALES O COMO PASTA PARA SOLDADURA POR PUNTOS Y, EN LA INDUSTRIA DEL ENVASADO, COMO MASA SELLADORA PARA CIERRES DE RECEPTACULOS O COMO MASA ESTANQUEIZANTE DE COSTURA O COMO ADHESIVO DE COSTURA DE REBORDES PARA LATAS. Plastisol compsns. (I) are claimed, based on styrene copolymers (II), plasticisers (III) and inorganic fillers. (II) are copolymers produced by emulsion polymerisation, contg. (A) styrene, alpha-methylstyrene and/or p-methylstyrene and (B) 3-20 wt.% (meth)acrylic acid and/or itaconic acid. - The styrene component of (II) contains up to 45 wt.% (w.r.t. styrene) butadiene, isoprene, piperylene and/or other rubber-forming comonomer, part of component (B) is replaced by methyl (meth)acrylate or (meth)acrylamide, and (II) contains 5-10 wt.% comonomer (B); (II) is in the form of powder with mean prim. particle size 0.3-1.5 microns and mean sec. particle size below 100 microns, and the copolymer has a core-shell structure with the polar gps. mainly on the outside; (I) also contain crosslinkers for (II) which react at the gelling temp., pref. long-chain epoxy cpds., epoxidised polybutadiene, epoxidised natural oils, di- or poly- OH-functional polyethylene or polypropylene glycols or copolymers thereof, OH-functional polybutadienes or SH-terminated liq. polymers; (I) also contain catalysts, pref. substd. imidazoles, tert. amines, tetramethylenediamine, urea derivs., alkylbenzenesulphonic acids or titanates, together with glycidyl (meth)acrylate as a further comonomer, and di- or poly-amines, di- or poly-carboxylic acids or mercapto cpds. to crosslink the epoxide gps.; (I) also contain, dissolved in (III), small amts. of polyurethane-formers, i.e. isocyanate prepolymers (IV) and (cyclo)aliphatic diamines, which react at gelling temp. to form PU; pref., (IV) have blocked NCO gps., and (I) contains up to 30 wt.% (IV) and up to 5 wt.% low-mol. wt. (c