Polypropylene

Unmodified polypropylene (PP) has the advantages of high rigidity and good heat resistance; however it also has poor impact, particularly at low temperatures. Combinations of Kraton® polymer and polypropylene have improved toughness at both room and low temperatures. These combinations can be quite clear.

Many applications areas for impact modified PP require an extreme balance of high flow, high stiffness, and excellent impact performance. In these applications, the PP used is a high melt flow (> 30g/10 min.) and it is often talc filled for stiffness. These combinations are used in thin walled part designs such as automotive instrument panels and exterior bumper systems.

For opaque applications, D1102, G1657, and G1652 are recommended.  D1102 and G1652 are small molecular weight grades and tend to give the best results due to their ability to form a fine dispersion. G1657 provides the best balance of flow, modulus, and impact strength in combinations with talc filled PP copolymer blends. Kraton G polymer should be used in applications that require good weatherability and aging performance.

For clear applications, MD6932 and MD6945 are recommended for use to modify clarified PP. Both products are dense pellets for easy handling and mixing.  When Kraton G polymer is combined with PP it can be steam, EO, EB, or gamma sterilized. Applications for Kraton impact modified PP includes tubing, film, and sheet.