Synthesis And Applications Of Polyurethane Material That Lay The Ground

Polyurethane flooring materials have a wide range of application and have been widely used. PU track is its most common application. Its synthesis is the chemical reaction of isocyanate-based. polyisocyanate and polyether polyol are the most important raw materials basic to the synthesis of polyurethane. The main synthetic method is the use of polyether polyol and isocyanate reaction. Plastic polyurethane used for paving the site, The process is commonly first preparing two component. Group A sub-component is a prepolymer. Prepolymer simperly to say are semi-finished products with polyisocyanate and polyol reaction of a certain percentage of the control. The experiment terminated prepolymer-NCO groups by capping. Part B includes ternary alcohol, fillers, various additives. then add various additives and mix the two component together.Finally dump the mixture to ground to form cured. In this thesis, the formulation of polyurethane flooring materials are designed and improved. Include the following three aspects:1. Only add TDI and polyether polyols of the traditional two-component curing system. in the synthesis of A prepolymer, the raw materials used polyether diols and 2,4-Toluene diisocyanate. The two Synthesized Group A sub-prepolymer by reaction, then mixing with the B sub-crosslinking. In this study, using a rotating viscometer to measurement viscosity of the prepolymer, using titration to measurement the prepolymer of NCO%. Observation the curing time of A and B component mixture of products. Using universal testing machine to measure tensile strength of cured products and elongation at break, etc. Analysis the influence of each component to the performance of prepolymer. Research the Filler and MOCA that impact on the product performance.2. Two-component curing system with TDI and MDI. The system prepolymer synthesis in addition to the reaction with TDI, and used MDI as the raw material that Provide the free -NCO groups. MDI relative to TDI its toxicity is much less, compared with the system to add TDI only the traditional system has obvious advantages. In this study, in addition to test the viscosity of prepolymer, NCO value, curing time, products, mechanical properties, also used Fourier transform infrared spectroscopy (FT-IR) characterization of the TDI, MDI and prepolymer functional groups.3. New one-component moisture curable system. The system does not add the curing cross-linking agent. The system mainly through the components of the NCO group with air and moisture in the substrate cross-linking curing reaction. Compare with the two-component curing system, this system have many advantages such as less pollution, simple operation, and long storage time. TDI with polyol synthesis group A. Polyol, filler, dispersant, solvent with high-speed dispersion to form part B. Adjust the components of the viscosity, in order to has a good mix of liquidity. Analysis the influence on the mechanical properties of filler, the type and amount of polyols. Under this system, the tensile of the products strength can reach 2 MPa, elongation also reach 350%. The performance of the products synthesized meet the national standards.