A process is provided for preparing polymer composites from compositions comprising i) a polyolefin, ii) a polymer selected from the group consisting of polymers having hydroxyl groups and polymers having amino groups and iii) a polar ethylene copolymer having copolymerized units selected from the group consisting of C.sub.4-C.sub.8 unsaturated anhydrides, monoesters of C.sub.4-C.sub.8 unsaturated acids having at least two carboxylic acid groups, diesters of C.sub.4-C.sub.8 unsaturated acids having at least two carboxylic acid groups and mixtures thereof. The process is suitable for use with recycle streams that contain polymeric materials that are laminates or composites of dissimilar polymers.