HEAT SEALABLE COATING COMPOSITIONS

摘要

A dispersion of polymer microparticles in organic liquid obtainable by a process comprising the steps of i) providing a mixture comprising a first po lymer having functional groups capable of reacting with the carboxylic acid and/or carboxylic acid anhydride groups of a second, polypropylene polymer i i) causing the polymers to melt at a chosen temperature under conditions of high shear, preferably in an extruder, to form an intimate mixture iii) caus ing the carboxylic acid and/or carboxylic acid anhydride groups of the polyp ropylene polymer to react with at least some of the functional groups of the first polymer, under conditions of high shear, preferably in an extruder iv ) diluting the resulting mixture of step iii) with an organic liquid at a te mperature such that a substantially homogeneous solution is formed v) coolin g the solution to a temperature whereby the polymer microparticles of the di spersion are formed.