GRAFTED POLYOLEFINS USEFUL AS METAL ADHESION PROMOTERS

• Main Authors: SYED, ABUZAR, WEFER, JOHN, M
• Format: Patent
• Language: English; French
• Published: 24.04.2008
• Subjects: ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; ADHESIVES; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; DYES; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PERFORMING OPERATIONS; POLISHES; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; USE OF MATERIALS AS ADHESIVES; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

An improved method for producing polypropylenes grafted with acrylic acid by means of reactive extrusion using an organic peroxide is disclosed, wherein the improvement comprises feeding the acrylic acid and the peroxide into the extruder downstream from the point where the polypropylene is introduced; wherein the acrylic acid is added at a feed rate greater than 25 pounds per hour, the. peroxide is added at a feed rate greater than 2 pounds per hour, and the total rate is greater than 500 pounds per hour; and whereby the PP-g-AA thus produced has a melt flow rate greater than about 200 dg per minute. L'invention porte sur un procédé amélioré de production de polypropylènes greffés par de l'acide acrylique par extrusion réactive et à l'aide d'un peroxyde organique. Les améliorations consistent: à introduire l'acide acrylique et le peroxyde dans l'extrudeuse en aval du point d'introduction du polypropylène, le débit d'introduction de l'acide acrylique dépassant 25 livres/h, celui du peroxyde dépassant 2 livres/h et le débit total dépassant 500 livres/h, et le PP-g-AA ainsi produit ayant un indice de fluage supérieur à environ 200 dg/minute.