The performance of polymer materials not only depends on the raw material formula, but also has a lot to do with the operating process parameters.
For polyurethane elastomers, the process factors that affect its performance include synthesis temperature/time, environmental humidity, operating steps, post-curing temperature and time, etc.
(1) Prepolymerization temperature and time Appropriate reaction temperature can synthesize prepolymers or polyurethane products with good performance. At the same time, attention should be paid to the balance between temperature and time. If the reaction temperature is high, the time required to complete the reaction will be short; otherwise, the time required will be long, which will affect production efficiency.
(2) Curing temperature: After the prepolymer is mixed with the curing agent, the higher the reaction temperature, the faster the curing, the shorter the life of the kettle, and the reduced operating time
(3) Synthesis process The synthesis process of polyurethane elastomers includes one-step method, prepolymerization method, and semi-prepolymerization method. The same raw materials and formulas adopt different synthesis processes. If the reaction temperature is different, the properties of the elastomer are also different.
(4) Environmental humidity Isocyanate easily reacts with moisture. If the ambient humidity is high, it may affect the reaction and product performance, especially for room temperature curing systems: the curing time is long, and the polyurethane surface is in contact with air during the curing process, and the product performance is more likely to be affected.