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2019-03-28
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 pre...
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2019-03-25
25.44 26.12 26.68 27.18 27.63 28.07 28.52 29.00 29.53 30.11 30.75 31.43 32.17 500 24.88 25.57 26.14 26.62 27.06 27.48 27.91 28.37 28.87 29.43 30.03 30.70 450 24.36 25.06 25.63 26.11 26.54 26.95 27.36 27.79 28.26 28.79 29.37 400 23.85 24.58 25.16 25.65 26.07 26.46 26.85 27.26 27.71 28.21 350 23.37 24.12 24.73 25.22 25.64 26.03 26.40 26.79 27.21 300 22.89 23.68 24.31 24.82 25.25 25.63 25.99 26.37 25...
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2019-03-20
Differential scanning calculation (DSC) is a technique that under temperature control program, used to determine the relationship between the heat flow rate or power difference of samples and reference materials, and temperature or time under program control temperature. DSC has been widely used in the fields of material processing, chemistry, medicine, biochemistry, petroleum, aerospace, environm...
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2019-03-08
1.Brief introduction Due to influence of thermal history, various properties of polymers will change, especially thermal properties of crystalline polymers. Thermal history of polymer is affected by various factors such as preparation process, storage conditions, and usage environment. Usually, thermal history of materials is studied by thermal analysis and viscoelasticity measurement. This paper ...
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2019-01-02
The glass transition, thermal degradation, thermal oxygen degradation and desorption of ABS / PVC / NBR alloy were studied by DSC, TGA and TMA techniques. The HCl process and deformation characteristics are systematically studied.The results show that various changes in ABS / PVC / NBR alloy are accompanied by changes in energy, mass and geometry. Glass transition temperature is an important param...
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2018-12-20
Thermal analysis has been applied in many fields, and various materials and sizes of thermal analysis sample pans have appeared accordingly.Its effectiveness can be obtained not only academically but also industrially.As an application field, inorganic materials such as metals, minerals, ceramics, glass and high molecular materials such as plastics and rubber are self - evident, and all substances...
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2018-12-05
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 produ...
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2018-08-21
1.Melting sample by the heat released during combustion process, and adding fluxing agent can decrease melting point. 2.Not only fluxing, tungsten-Tin accelerator also has function of heat release, acidity-alkalinity adjustment of medium, mixing, catalyzing, stabilizing combustion, anti-interference, etc. 3.Tungsten-Tin accelerator is widely used in high frequency furnace, and it can fulfill techn...
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2018-07-09
Generally, Al2O3 ceramic means ceramic that with α-Al2O3 as the main crystalline phase, and content of Al2O3 is between 75%~99.9%. Customarily, as a commodity, Al2O3 is named according to the nominal content, for instance, #99 ceramic means nominal content of Al2O3 is 99%, and #95 ceramic means nominal content of Al2O3 is 95%. For ceramic that Al2O3 content is higher than 85%, it’s called high alu...
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2018-06-07
Purpose of forming is to produce semi-finished product with certain shape by powder, and the methods are as follows: 1.Direct powder forming, or called powder pressing, such as rigid module pressing, ramming forming, cold isostatic pressing, dry bag isostatic pressing, etc. 2.Plastic lump material forming, also called plastic forming simply, such as plastic blank pressing, roll forming, etc. ...