Study Of The Heat-resistance Property Of The Polyurethan Elastomer

Polyurethane elastomer, it also calls the polyurethane elastomer, is on a kind of high polymer composition material which principal chain includes many carbaminate groups. It has big elongation ratio, broad hardness range; abrasion resistance , the biological compatibility and the blood compatibility are specially prominent. At the same time, it also has outstanding oil resistant, bears the impact, bears the low temperature, bears radiates and heavy load, heat insulation, and so on isolation. It is situated between the common rubber and the plastic elastomer material, both has the rubber high elasticity, and has plastic high trength. Therefore, the polyurethane elastomer's application is widespread. It already becomes the essential precious material in the national economy and the lives of the people.This report uses Prepolymer law, through the single factor experiment, had determined the polyurethane elastomer's synthesis condition, and uses one kind of high performance poly hydrogens to prepare the casting polyurethane elastomer mellowly, the synthetic elastomer mechanical properties are fine, the transparency is good. Through the modification, enhanced the polyurethane elastomer heat-resisting performance. And has made the desk study to the polyurethane elastomer's thermally stable mechanism. The polyurethane elastomer synthesis condition is as follows:Raw material quality allocated proportion: Polyester polyols∶TDI∶MOCA=8∶2∶1; Polyether polyols∶TDI∶MOCA=10∶2∶1The outset reaction temperature: 60℃, not lead the air bubble as far as possible in the situation the fast agitation; The nature elevates temperature to 80℃and keeps reaction about 2 hours. The best chain extendor is MOCA, after joining MOCA, uses the glass rod agitation again approximately 2-3min, pours in the preheating 100℃mold. After the solidification, puts to 120℃drying oven in curing 4 hours. Escapes the membrane, it is the polyurethane elastomer product.The elastomer thermal stability increases with NCO% content enhances, when NCO% achieve about 5%, the thermal stability achieves best, later will present the declining trend. MOCA joins the quantity also to have the similar tendency to the polyurethane elastomer thermal stability, when joins the quantity is TDI half quality, its thermal stability achieves best. The gathers weighing of - NCO influence elastomer mechanical properties immediate. Elastomer degree of hardness, the longitudinal strength and the peel strength basic increase along with - the NCO matrix weighing out number enhance, but the elongation ratio actually to drop.The polyester polyurethane elastomer's water resistance is ordinary, the oil resistant performance is good; But the polyether polyurethane elastomer water resistance is good, oil resistance weakly in polyester elastomer.The polyester polyurethane elastomer thermal stability surpasses the polyether polyurethane elastomer. The modified polyester polyurethane elastomer thermal stability has the distinct enhancement, the outset decomposition temperature may enhance approximately 60℃-80℃, the biggest heat absorption decomposes the temperature enhances approximately 33℃-117℃.The modified polyether polyurethane elastomer outset decomposition temperature may enhance approximately 22℃-44℃, the biggest heat absorption decomposes the temperature enhances for 22℃-30℃.