 Wysłany: Czw 0:28, 02 Gru 2010 Temat postu: uggs online HFC-245fa in the refrigerator insulati |
|
| HFC-245fa in the refrigerator in the application of insulation materials
R-OH + R-NC 'Bu RNHCOORR-NCO + H20 a RNH2 + CO = CO gas produced by reaction with the endothermic gasification offers HFC 245fa foam required for a gas source, so that the hydrogen-based ester, etc. Results dig dig the formation of many tiny air bubbles into the porous foam structure. 3.2 The improvement of thermal conductivity is a measure of thermal conductivity of polyurethane foam insulation alcohol an important indicator of performance, in the refrigerator, freezer, the thermal conductivity directly affects the size of refrigerators, freezers power consumption. Polyurethane foam heat transfer in three ways, first by the gas, and about 50% of the total; second alcohol-based body conducted by the polyurethane, and approximately 20% of the total; third transmitted by radiation, about the total 3O%. Compared with the CFC for a 11, HFC - 245fa has a high thermal conductivity of vapor, resulting in the overall foam thermal conductivity coefficient. That part of the radiation heat transfer, can reduce the foam to reduce the emission factor approach. Reduce the foam to achieve the purpose of the overall thermal conductivity. Radiation factor on the bubble foam has a strong dependence, if made of very fine and uniform foam, this factor can be reduced to a minimum. Therefore,uggs online, you can choose groups with specific Synthesis of the starting polyether polyol, polyether polyol molecule in the introduction of specific groups and vend the optimization side foam structure has been optimized to achieve uniform granular foam save the fruit, thereby reducing the thermal conductivity. We chose the starting aromatic polyether polyols were synthesized 505, with its polyether as the main body. Vend side by optimizing thermal conductivity of the foam obtained has been greatly improved,uggs online, close to the CFC for a 11-type performance of similar products. Improve the adhesive strength of 3.3 in the refrigerator foaming process, foam and refrigerators in the liner and shell materials should have good adhesive properties, otherwise it will create degumming has seriously affected the quality of products refrigerator. As HFCm245fa low boiling point boiling point {15.3 ℃), the foaming process, a large number of early in the gasification reaction, the reaction will be a large number of tropical away, leading to the bubble surface fat cakes crisp,mac makeup wholesale, affecting the foam and refrigerators inner shell and bonding properties of the material. When the synthesis of polyether polyol initiator, and water content of a certain combination of polyether, the improvement of the bubble surface and the crisp performance of the method is generally revolves take is to change the polyether polyol of hydroxyl value, in general, reduce the polyether hydroxyl value of polyols, foam will help to improve the surface properties of crisp pick of fools, but will reduce the foam compressive strength and other properties. To this end we will polyether polyol of hydroxyl value of 505 at an appropriate level of control, with its crisp surface as the base of the foam problem had been resolved, and the housing bubble and Refrigerator Liner adhesive properties of the material has been significantly improved. And the intensity remained at a high level. 4 Conclusion HFC - 245fa as a new environmentally friendly blowing agents, foreign countries have begun in the refrigerator insulation material in the trial. Red Polaroid Corporation and China Household Electrical Appliances Research Institute, started in 1998,UGG Boots Outlet, HFC - 245fa with the combination of polyether of refrigerators, after more than two years of technical research, through the polyether polyol, catalyst, foam stabilizer screening test and other raw materials. Successful development of a refrigerator with HFC - 245fa combination of polyether,moncler outlet, the China Household Electrical Appliances Quality Inspection Center pull test certificate. The product of the parameters and foam products, foam performance has reached a 11 CFC technology similar products available in China's refrigerator industry in promoting the use. References 1 Xia Zhongliang, refrigerator units together with a cyclopentane group of polyols shoes and Application Development. PU China '98 Second International Symposium on ship 2llled roundworm a1 Company HFC - 245fa product specifications 19973H ・ P ・ D0 stare BeNewDevel. pme Ⅱ binHFC a 245faAppE-a foamPolytwethanesWorlclCon ~ '97September29 a october1, 1997, Bayer0on4N ・ TSUKIDA. H ・ SATO. M ・ AOYAGIANDTAKEYASUNEWPOLYOLsANDFORMULATIONSFORENERGY-SINGINSULATIONUsINGHFC a 245ASOWINGAGENTPolyurethanesWorldCon ~ ew'975 Li Shaoxiong, Lu Min Zhu, Yin PVC resin, Nanjing, Jiangsu Science and Technology Press, I993 {entropy Series Han Bin) More articles related to topics： tory burch flip flops Siemens Fridge de-saving ide ugg boots uk Reliability of technical seminars beg tory burch sale Induction motor current DECOUPLING |
|
