EXPANDABLE VINYL AROMATIC COMPOSITION CONTAINING FUNCTIONALIZED ETHYLENE-VINYL ACETATE COPOLYMER

• Main Authors: Giovanni CUDER, Stefano COMBA, Aldo LONGO
• Format: Patent
• Language: English; Spanish
• Published: 11.02.2019
• Subjects: ADHESIVES; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMICAL PAINT OR INK REMOVERS; CHEMISTRY; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COMPOSITIONS BASED THEREON; CORRECTING FLUIDS; DYES; FILLING PASTES; GENERAL PROCESSES OF COMPOUNDING; INKS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; POLISHES; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF MATERIALS THEREFOR; WOODSTAINS; WORKING-UP

The present invention relates to polymeric compositions that can be used for producing packaging with dynamic cushioning, with a pleasant touch, with reduced abrasive power, in which the expanded particles constituting the packaging adhere well to one another and do not come detached during use. Said compositions comprise: a) from 70% to 90% by weight of a vinyl aromatic polymer and/or copolymer, calculated with respect to (a) + (b); b) from 10% to 30% by weight of an ethylene-vinyl acetate copolymer (EVA) containing a percentage that ranges from 10% to 30% by weight of vinyl acetate, calculated with respect to (a) + (b); c) from 3 to 10 parts by weight of a blowing agent, calculated on 100 parts of component a) added to component b); said copolymer (b) being distributed in the polymer (a) in the form of particles having an average volumetric diameter ranging from 1 nm to 2000nm. The compositions described and claimed do not include styrene-butadiene or styrene-isoprene block copolymers, hydrogenated or non-hydrogenated; thermoplastic polyurethanes, polystyrene- butadiene grafted polymers or styrene core-shell polymers. La presente invención se refiere a composiciones poliméricas que se pueden utilizar para envases con acojinamiento dinámico, con un tacto agradable, con potencia abrasiva reducida, en los cuales las partículas expandidas que constituyen el envase se adhieren bien entre sí y no se llegan a desprender durante el uso. Estas composiciones comprenden: a) de 70% a 90% en paso de un copolímero y/o polímero aromático de vinilo, calculado con respecto a (a) + (b); b)de 10% a 30% en peso de un copolímero de etileno acetato de vinilo (EVA) que contiene un porcentaje que varía de 10% a 30% en peso de acetato de vinilo, calculado con respecto a (a) + (b); c) de 3 a 10 partes en peso de un agente de soplado, calculado en 100 partes del componente a) adicionado al componente b) ; este copolímero (b) que se distribuye en el polímero (a) en la forma de partículas que tienen un diámetro volumétrico promedio que varía de 1 nm a 2000 nm. Las composiciones descritas y reivindicadas no incluyen copolímeros de bloque de estireno hidrogenado o no hidrogenado-butadieno o estireno hidrogenado o no hidrogenado-isopreno; poliuretanos termoplásticos, polímeros injertados de poliestireno-butadieno núcleo-cubierta.