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81.
The equation of state model developed by Lacombe and Sanchez (J Phys Chem 1976, 80, 2352) is used in the form proposed later by Sanchez and Stone (Polymer Blends, Vol. 1: Formulation, 2000; Chapter 2) to correlate experimental vapor‐liquid equilibrium (VLE) data for the three binaries and the ternary systems. Experimental data from the binary systems carbon dioxide‐isopropyl alcohol (CO2‐IPrOH), isopropyl alcohol‐polystyrene (IPrOH‐PS), and carbon dioxide‐polystyrene (CO2‐PS) are used to calculate VLE properties for the ternary system CO2‐IPrOH‐PS. Two‐dimensional VLE‐phase diagrams were calculated and used to describe from a thermodynamic point of view the pressure, volume, and temperature values that characterize a thermoplastic foam evolution process, from the extruder to the foaming die. For different initial mixture CO2 + IPrOH concentrations, pressure reduction produces liquid foaming until the vitrification curve arrests the final foam volume expansion. The dependence of the vitreous transition with the system CO2 + IPrOH concentration while foaming is represented by the Chow (Macromolecules 1980, 13, 362) equation. The calculation procedure is proposed as a design tool to reduce the amount of experimental data usually needed as a requirement previous to the design stage. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2663–2671, 2007 相似文献
82.
水性聚氨酯胶研究及应用 总被引:12,自引:0,他引:12
综述了国内外水性聚氨酯胶特点及应用,对水性聚氨酯乳液的制备及物理性质和聚氨酯胶层的性能进行分析和阐述。 相似文献
83.
84.
用硫酸厂硫铁矿焙烧后的粉尘掺入聚氯乙烯中,用挤出成型法挤制硬质聚氯乙烯塑料管,以扩大聚氯乙烯塑料的用途。 相似文献
85.
Jia Bing Dai Xing Yuan Zhang Jing Chao Chen Yan Bai 《Journal of Coatings Technology and Research》2007,4(3):283-288
A novel core–shell type fluorinated acrylic and siliconated polyurethane (FSiPUA) hybrid emulsion was prepared by seeded emulsion
polymerization using siliconated polyurethane (SiPU) as a seed and forming the structure with SiPU as a shell and the copolymer
of butyl acrylate (BA) with 2,2,2-trifluoroethylmethacrylate (TFEMA) as a core. SiPU was synthesized using isophorone diisocyanate
(IPDI), polytetramethylene ether glycol (PTMG), polypropylene glycol (PPG), dihydroxybutyl-terminated polydimethylsiloxane
(PDMS), dimethylol propionic acid (DMPA), 1,6-hexanediol (HDO) and triethylamine (TEA). The contents of siloxane and fluorine
were determined according to the feed ratio. Fourier transform infrared spectroscopy (FTIR) was used to identify the chain
structure of SiPU and FSiPUA. Investigation of transmission electron microscopy (TEM) confirmed the core–shell structure of
FSiPUA emulsion and gave the particle size at about 50 nm. The measurement results of water contact angles and the solvent
absorptions in water and n-octane for cured films showed that the water and the oil repellency for FSiPUA had been improved significantly with a suitable
content of fluorine and siloxane. 相似文献
86.
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Low crosslinked copolymer of linear and hyperbranched polyurethane (CHPU) was prepared, and the ionic conductivities and thermal properties of the composite polymer electrolytes composed of CHPU and LiClO4 were investigated. The FTIR and Raman spectra analysis indicated that the polyurethane copolymer could dissolve more lithium salt than the corresponding polymer electrolytes of the non crosslinked hyperbranched polyurethane, and showed higher conductivities. At salt concentration EO/Li = 4, the electrolyte CHPU30‐LiClO4 reached its maximum conductivity, 1.51 × 10?5 S cm?1 at 25°C. DSC measurement was also used for the analysis of the thermal properties of polymer electrolytes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3607–3613, 2007 相似文献
88.
研究了在GB/T18446-2001方法基础上改变内标物(使用无毒性记录的十二烷代替毒性大的1,2,4-三氯代苯)测定样品中游离TDI的方法。该方法简捷、快速、准确度高、精确度高、更环保。本方法的适用范围同GB/T18446-2001。 相似文献
89.
研制的填充用聚氨酯硬泡组合料,具有料液稳定、流动性好,所制泡沫泡孔均匀、开孔率高、不易收缩等特点。该组合料制得的泡沫性能为:泡沫密度15kg/m^3,开孔率大于98%,流动性大于1.3cm/g,压缩强度大于0.1MPa。 相似文献
90.