What is the principle of solid phase viscosity increasing发表时间:2023-03-25 16:15 Solid state viscosity increasing, also known as solid state polycondensation, is a polycondensation reaction carried out in a solid state. A polyester prepolymer with a certain molecular weight is heated to a glass transition temperature below its melting point (usually 10-40 ℃ below the melting point), and small molecular products are taken away through vacuum pumping or inert gas protection to continue the polycondensation reaction. Thepolycondensation reaction occurs due to spherical regions and effective collisions. The existing solid state viscosity increasing processing methods usually use vacuum drum type viscosity increasing equipment, which is composed of a rotatable cylinder and a heating jacket. The cylinder is provided with feed and discharge ports, as well as inlet and outlet ports for heating medium and vacuum pumping. When used, it does not uniformly heat the internal raw materials, and does not have a detection instrument to detect the internal pressure and temperature, making it difficult to control the processing environment, and it is not convenient to conduct vacuum extraction processing. 上一篇压稀相气力输送系统的特点
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