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1.Experimental part 1.1 Raw material Ammonia ester modified liquefied MDI (U-MDI ), NCO%=28.4 %, functionality 2, ethylene oxide terminated polypropylene oxide polyether (PPO), ZS-2185, Mn=2000, [K+]<5ppm, primary hydroxyl content>70%  in DETDA, 2,4-isomer/2,6-isomer=80/20. MDA and catalyst dibutyltin dilaurate are chemical reagents, catalyst dosage: 2.0×10-1g cat./g PPO. 1.2 Sample preparation The raw materials are kept at 40 ℃. PPO, diamine chain extender and catalyst (component a) and u-MDI (component b) are mixed by 200g in a 50ml plastic beaker and poured into a mold with a Beder stirrer (1600r/min), the materials react quickly in the mold and are molded, the samples are taken out after 1-2 mins, the post-curing conditions are 120 ℃/30 min, and then maintained at 60℃ for 7 days. 1.3 DSC test Du Pont 1090 thermal analyzer and its matching thermal analysis crucible was heated at -120~250℃ and temperature raise at 20℃/min in N2 atmosphere, and ...

Thermal analysis technology is a group of technologies to characterize the relationship between the properties of materials and temperature. It is widely used in qualitative and quantitative characterization of thermal, physical, mechanical and stability properties of materials, and has very important practical significance for the research and development of materials and quality control in production.At present, thermal analysis technology is increasingly becoming one of the indispensable and important means in the research, development and quality control of rubber materials. Thermal analysis technology is a group of technologies to characterize the relationship between the properties of materials and temperature. It is widely used in qualitative and quantitative characterization of thermal, physical, mechanical and stability properties of materials, and has very important practical significance for the research and development of materials and quality control in...