Preparing And Developing Special Purpose Material For Pressure Pipe In Bimodal PE80Class

Bimodal distribution of the molecular weight endows polyethylene resin good stiffness, toughness, processability and the best combination thereof. Thus, the comprehensive property of PE pipe made a great leap essentially since its production technique came forth. This program focused on preparing and developing pressure pipe speciality in bimodal PE80class with the excellent mechanical and long-term hydrostatic resistance properties. Finally it can be stably produced in batches in High Density Polyethylene (HDPE) plant in Beijing Yanhua Petrochemical Company Limited with a brand HDPE6380M. The study mainly introduced HDPE6380M in terms of molecular structure design, analyse of structure and properties and relevant classification authentication of special pipe material. After investigating this product by means of gel permeation chromatography, nuclear magnetic resonance, differential scanning calorimetry, mechanical, rheological and hydrostatic pressure properties testing and etc., it was found that HDPE6380M possess specific structural character of bimodal molecular weight distribution and appropriate content of the selected comonomer. It also indicated that the rational equilibrium between stiffness and toughness was realized in this material besides its good processability.6380M passed though the classification authentication of PE80class in10,000hours carried out in accordance with the method of ISO/TR9080:1992. HDPE6380M became the first domestic speciality resin for manufacturing pressure pipe.