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11.
采用含有二乙二醇(DEG)和乙醇胺(ETA)的双组分解交联剂降解废旧硬质聚氨酯泡沫塑料(PU硬泡),并利用降解得到的低聚物多元醇与木质素复合制备出性能增强的再生PU硬泡。通过对制备的再生PU硬泡的红外光谱、密度、吸水率、抗压强度、热稳定性、导热系数、热重曲线等进行分析测试,考察m(DEG)∶m(ETA)对再生PU硬泡性能的影响。实验结果表明:m(DEG)∶m(ETA)=1∶3时废旧PU硬泡的降解效果最好;木质素加入量为2.0%(w)时再生PU硬泡的密度低、抗压强度高、保温性能良好,达到国家标准《建筑绝热用硬质聚氨酯泡沫塑料》(GB/T 21558—2008)的品质要求。 相似文献
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本文研究了空心玻璃微珠添加量及泡沫液浓度对泡沫灭火剂发泡能力和稳定性的影响,对比了热辐射条件下空心玻璃微珠添加前后泡沫的热稳定性.结果表明,添加量低于40%时,空心玻璃微珠对泡沫灭火剂发泡能力影响不大,而泡沫的稳定性显著降低,添加量为50%时,虽泡沫发泡能力降低,但泡沫的稳定性却增强.泡沫的发泡能力随蛋白泡沫浓度升高而增强.蛋白浓度为10%,空心微珠添加量为50%时,由于泡沫内部形成了稳定的三相泡沫骨架结构,泡沫热稳定性较未添加微珠之前显著增强. 相似文献
14.
Dechlorination of polyvinyl chloride in NaOH/ethylene glycol solution by microwave heating 总被引:1,自引:1,他引:0
This study investigated the dehydrochlorination of flexible polyvinyl chloride (PVC) containing 59.2% PVC, 29.7% dioctyl phthalate
(DOP), and approximately 12% stabilizers. Flexible PVC was treated with NaOH/ethylene glycol (NaOH/EG) solutions at NaOH concentrations
in the range 0.5–4 mol/l and was heated in a microwave heater at a temperature between 100° and 160°C for 0–30 min. All chlorides
were completely eliminated by internal heating at 160°C using microwaves for 10 min in a 1 mol/l NaOH/EG solution, and the
residue was made up of hydrocarbons. The weight loss rate reached a maximum of 74.7% at a temperature of 160°C. It was discovered
that the use of microwaves significantly shortened the reaction time compared to using conventional electric heaters or other
external heating systems and also allowed the use of lower concentrations of NaOH.
Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6 相似文献
15.
以聚氨脂泡沫填缝剂基本生产原理及其特点为基础,对生产原料进行火灾危险性分析,结果表明:该类生产场所的火灾危险等级应划分为甲类;提出聚氨酯泡沫填缝剂生产中存在的安全问题及原因;运用危险度评价法对聚氨脂泡沫填缝剂生产工艺的火灾危险性进行了定量的安全评价,得出聚氨脂泡沫填缝剂生产工艺的危险程度为高度危险;并从建筑设计、防火管理和生产工艺等方面提出了预防火灾事故发生的对策。 相似文献
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利用废旧冰箱拆解的聚氨酯泡沫塑料(PU)和聚丙烯(PP)、聚丙烯接枝马来酸酐(PP-g-MAH)为原料,采用物理化学回收技术制备PU/PP复合材料。用正交实验法分析PU填充量、PU粒径和PP-g-MAH 3个因素对PU/PP复合材料力学性能影响的显著性。结果表明,PU填充量对PU/PP复合材料拉伸性能有显著影响,对冲击性能和弯曲性能没有显著影响;在本文的实验范围内,PU粒径对PU/PP复合材料的力学性能影响不大;而PP-g-MAH投加量对PU/PP复合材料具有一定的影响。确定的优化工艺配方为:PU 40%;PU粒径选择2.00 mm;PP-g-MAH投加量10%。采用优化工艺制备的PU/PP复合材料的密度为1 042.88 kg/m3;冲击强度为2.9 kJ/m2;拉伸强度为10.30 MPa;拉伸模量为1 100 MPa;弯曲强度为18.5 MPa;弯曲模量为733 MPa。 相似文献
18.
The effect of the addition of materials on the leaching pattern of As and metals (Cu, Zn, Ni, Pb, and Cd) in two contaminated soils was investigated. The examined materials included bentonites, silicates and industrial wastes, such as sugar foam, fly ashes and a material originated from the zeolitization of fly ash. Soil + material mixtures were prepared at 10% doses. Changes in the acid neutralization capacity, crystalline phases and contaminant leaching over a wide range of pHs were examined by using pHstat leaching tests. Sugar foam, the zeolitic material and MX-80 bentonite produced the greatest decrease in the leaching of pollutants due to an increase in the pH and/or the sorption capacity in the resulting mixture. This finding suggests that soil remediation may be a feasible option for the reuse of non-hazardous wastes. 相似文献
19.
Moe MK Huber S Svenson J Hagenaars A Pabon M Trümper M Berger U Knapen D Herzke D 《Chemosphere》2012,89(7):869-875
For several decades, perfluorooctane sulfonate (PFOS) has widely been used as a fluorinated surfactant in aqueous film forming foams used as hydrocarbon fuel fire extinguishers. Due to concerns regarding its environmental persistence and toxicological effects, PFOS has recently been replaced by novel fluorinated surfactants such as Forafac®1157, developed by the DuPont company. The major component of Forafac®1157 is a 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB), and a link between the trade name and the exact chemical structure is presented here to the scientific community for the first time. In the present work, the structure of the 6:2 FTAB was elucidated by 1H, 13C and 19F nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. Moreover, its major metabolites from blue mussel (Mytilus edulis) and turbot (Scophthalmus maximus) and its photolytic transformation products were identified. Contrary to what has earlier been observed for PFOS, the 6:2 FTAB was extensively metabolized by blue mussel and turbot exposed to Forafac®1157. The major metabolite was a deacetylated betaine species, from which mono- and di-demethylated metabolites also were formed. Another abundant metabolite was the 6:2 fluorotelomer sulfonamide. In another experiment, Forafac®1157 was subjected to UV-light induced photolysis. The experimental conditions aimed to simulate Arctic conditions and the deacetylated species was again the primary transformation product of 6:2 FTAB. A 6:2 fluorotelomer sulfonamide was also formed along with a non-identified transformation product. The environmental presence of most of the metabolites and transformation products was qualitatively demonstrated by analysis of soil samples taken in close proximity to an airport fire training facility. 相似文献
20.
采用前驱体改性的方法,以CuCl2、FeCl2和MgCl2为改性剂,制备出改性酚醛泡沫,经炭化/活化得到改性酚醛基炭泡沫。研究了不同金属对酚醛基炭泡沫表面物理与化学特性的影响,并进行同时脱硫脱硝实验研究。通过研究发现,添加CuCl2的样品比添加FeCl2、MgCl2的样品的中孔孔容大接近10倍;比表面积和孔容是CFCu>CF0>CFFe>CFMg;金属改性剂主要以金属和金属氧化物的形式存在于酚醛基炭泡沫中,而表面其他官能团大体结构不变。经CuCl2、FeCl2和MgCl2改性后,脱硫效率分别提高了39%、11%和13%,脱硝效率分别提高了19%、10%和4%,其中以CuCl2改性的酚醛基炭泡沫的效率最高。 相似文献