Martin Lackner and Carl-Gustaf Ek
Papers # 2012 Barcelona
Key words : Polypropylene, Sewage, Sustainability, Durability, High-modulus Polypropylene has an excellent track record after more than 30 years of service for nonpressure sewage and drainage applications. The inherent material properties and their development, energy and cost efficiency, pipe design and ease of manufacture and installation have contributed to this success. The traditional cornerstones of the requirements profile such as impact resistance, stiffness and chemical resistance are increasingly being supplemented by demands for purity, sustainability and recyclability. Consequently, the continuous development seen in both material and pipe design has brought additional benefits to the members of the value chain and to a sustainable society. The first generation of PP with higher modulus PP was introduced in 1998 and provided a major step forward with an optimized balance of the stiffness-impact properties. A few years later, this product was improved and an E-modulus of 1700 MPa was achieved, representing the first PP-HM to meet the requirements set in the modified EN1852 standard in 2002 (which was adjusted based on the development of this new class of polypropylenes). The journey has continued and this paper reflects on the recently introduced next generation PP for underground drainage and sewage. It presents the first PP-HM with an E-modulus of above 2000 MPa, achieved without the use of fillers, meeting and exceeding the requirements set in the recently - again - modified EN1852. Recent developments of PP for non-pressure pipe applications are reviewed demonstrating the contribution of PP systems to sustainable waste water management and to the reduction of material and energy consumption throughout the various stages of production, transportation and use. Is this the end of polypropylene development for sustainable underground sewage and drainage or just the beginning? An outlook on the next development steps for PP is presented.
