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介绍了聚氨酯发泡剂CFC-11的主要替代品HCFC-141b的生产工艺和生产现状,并分析了该产品的市场前景。 相似文献
3.
主要阐述FP石膏材料、制芯工艺过程及烘干工艺,阐述了应用硅橡胶母模复制石膏芯表面光洁度高,尺寸精度较好,硫化轮胎的铸造成品率达99%以上。 相似文献
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Abdellatif Mohamed Mila P. Hojilla-Evangelista Steve C. Peterson Girma Biresaw 《Journal of the American Oil Chemists' Society》2007,84(3):281-288
Barley protein isolate (BPI) was extracted in 0.015 N NaOH in a 10:1 ratio solvent:flour and was precipitated by adjusting
the pH to 4.5 and freeze-dried. The thermal properties of BPI were determined using modulated differential scanning calorimetry
(MDSC). BPI with 4% moisture content exhibited a glass transition (T
g) with 140 °C onset, 153 °C middle, and 165 °C end temperatures and a ΔC
p of 0.454 J/g per °C. The high moisture content sample (50%) showed a T
g at 89, 91, or 94 °C and 0.067 ΔC
p. Acetylation had no apparent effect on the foaming and emulsifying properties of protein from barley flour but exhibited
the least-stable foam among BPI samples. Foaming capacities of both barley protein isolates were ∼12% less than that of acid-precipitated
soy protein isolate reported in the literature. Acetylated BPI showed the highest surface hydrophobicity compared to the other
samples. The surface-tension test confirmed that unmodified and modified BPI possessed surface activity. BPI phosphorous oxycloride-crosslinked
was the most effective in lowering the surface tension of aqueous NaCl, while the crosslinked BPI was the least effective.
The G′ value of BPI suspension was greater than G″ at all frequencies from 0.1 to 100 rad/s. The strain value at which linear behavior ceased and nonlinear behavior began
ranged from 3 to 10%.
Names are necessary to report factually on available data; however, the United States Department of Agriculture (USDA) neither
guarantees nor warrants the standard of the product, and the use of the name by the USDA implies no approval of the product
to the exclusion of others that may also be suitable. 相似文献
6.
Soft rubber foams like poly(ethylene-co-vinyl acetate) (EVA) are industrially applied in a broad range of products, including sports gear, insulation materials and drug delivery systems. In contrast to glassy polymers, few studies in literature concern the foaming of soft rubbers using supercritical carbon dioxide. In this study, open microporous matrices of EVA have been formed with CO2. Prior to the foam expansion, sorption and swelling isotherms of CO2 in EVA have been measured and the obtained isotherms have been correlated using the Sanchez-Lacombe equation of state. Additionally, a pressure-independent diffusion coefficient of CO2 in EVA has been obtained from these experiments. The microporous foams have been formed by a pressure quench of the CO2-swollen polymer matrix. Sorption pressure as well as temperature and decompression times appear to determine the pore size and bulk density of the foam. These parameters allow for a control of the foam structure of EVA rubbers. 相似文献
7.
分析AC发泡剂原粉在应用中的一些缺陷;叙述改性AC的种类、改性的途径及我国改性AC的现状研究进展;探讨我国改性AC在品种和应用研究方面与国外的差距;应大力开发改性AC. 相似文献
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陈国华 《军民两用技术与产品》2015,(6)
介绍了传统无氟发泡工艺具体工况,分析了聚氨酯泡沫存在容易产生形变、强度和韧性不高和工艺中附加物分散性不佳等问题,本文提出一种改进的无氟发泡工艺,与传统的无氟发泡工艺相比,改进的无氟发泡工艺能有效解决聚氨酯泡沫易形变的问题,提高了聚氨酯的强度及韧性,增加了附加物的分散性效果,降低了发泡体系设备.对进一步改善无氟发泡工艺技术具有重要意义. 相似文献
10.
采用流变、常规量筒法、扫描电镜及显微镜,研究了优选出的3种弱凝胶与SD发泡剂的复配体系的起泡性能、黏度、稳定性以及微观结构。结果表明,起泡剂与弱凝胶复配之后,体系的各项性能得到明显改善。复配体系半衰期增大,泡沫黏度增大,稳定性增强,明显优于单一体系。在弱凝胶与泡沫复合调驱体系中,凝胶易在气泡表面形成吸附膜,将泡沫包裹在内部,增强了气液界面的黏度,使得泡沫不容易发生聚并破裂,从而增强了泡沫的稳定性以及黏度,使得其半衰期也增大。 相似文献