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Direct silanization of polyurethane foams for efficient selective absorption of oil from water 下载免费PDF全文
Absorption is an effective method to collect oil spills and solvent leakages from water. However, the currently used oil absorbents are still suffering from high cost, tedious preparation, and low recyclability. In this work, we report an extremely simple and low‐cost strategy to produce oil absorbents by directly coupling alkoxysilane onto the surface of polyurethane (PU) foams. Such direct silanization renders the initially amphiphilic foams a strong hydrophobicity and consequently a water‐repelling and oil‐absorptive functionality. The silanized foams exhibit highest absorption capacities as well as best recyclability among all PU‐based oil absorbents. More practically, the silanized PU foams can be used to recover crude oil spills with an absorption capacity of higher than 75 times of their own weight, and maintain 90% of the initial absorption capacity after eight times reusage. Interestingly, we invent portable oil suckers for continuous oil absorption from water by filling vacuum cleaners with the silanized foams. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2232–2240, 2017 相似文献
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Yan Hong Hu Yun Gao De Ning Wang Chun Pu Hu Stella Zu Lieve Vanoverloop David Randall 《应用聚合物科学杂志》2002,84(3):591-597
A new kind of polyol based on rape seed oil for use in rigid polyurethane foam was synthesized and characterized. The synthesis of such a polyol was divided into two steps. The first step was the hydroxylation of the double bonds existing in the long chains of the unsaturated aliphatic hydrocarbon of rape seed oil with peroxy acid. The second step was use of the alcoholysis of the hydroxylated rape seed oil with triethanolamine to increase the hydroxyl value of the product. The reaction process was monitored by means of a novel on‐line infrared spectrometer. Rigid polyurethane foam was produced with this rape seed oil based polyol and some physical properties of the foam were examined and compared with a reference foam. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 591–597, 2002; DOI 10.1002/app.10311 相似文献
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Shuai Wang Fukai Yang Wei Sun Xinyu Xu Yuyuan Deng 《Journal of the American Oil Chemists' Society》2023,100(7):561-577
Rigid polyurethane foam (RPUF) is prepared from petroleum-based polyols and isocyanate, which consumes a large amount of petroleum. To alleviate the consumption of petroleum, it is necessary to synthesize green and sustainable polyols. However, the greatest disadvantage of RPUF is its flammability. To reduce the risk of fire caused by RPUF, phosphorylated soybean oil polyol (Polyol-P) and phenyl phospho-soybean oil polyol (Polyol-PPOA) were synthesized by ring-opening reactions of epoxy soybean oil with phosphoric acid and phenylphosphonic acid, respectively. A flame-retardant RPUF was prepared via polymeric 4,4-diphenylmethane diisocyanate (p-MDI), which reacted after mixing Polyol-P and Polyol-PPOA with polyether polyol-330N in different proportions. Scanning electron microscopy (SEM) showed that the cell sizes of the RPUF-P and RPUF-PPOA increased first and then decreased and the cell number decreased first and then increased with the increase in the contents of Polyol-P and Polyol-PPOA. Mechanical property tests showed that the compressive strength of the RPUF-P4 reached 0.1 MPa, and the compressive strength of the RPUF-PPOA4 reached 0.07 MPa. The limiting oxygen index values of the RPUF-P4 and RPUF-PPOA4 were 20.9% and 24.3%, respectively. The UL 94 of the RPUFs indicated that the rating of the RPUF-PPOA3 was improved to V-1. The results showed that the flame-retardancy mechanism of the Polyol-P and Polyol-PPOA in the RPUF was based on the charred surface as a physical barrier, which slowed down the decomposition of RPUF and prevented heat and mass transfer between the gas and the condensed phase. 相似文献
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In order to enhance the oil–water separation properties of polyurethane foam (PFU), hydrophobic silica nanoparticles (H-SiO2 NPs) were firstly prepared by incorporating long alkyl chains into silica nanoparticles, and then, it was combined with PFU by in situ loading to fabricate a hydrophobic PFU (H-SiO2 NPs/PUF). When the loading amount of H-SiO2 NPs was 10%, the water contact angle of the modified foam H-SiO2 NPs/PUF-10 reached 147 ± 1°, which proved it was highly hydrophobic. The elongation at break of the foam was increased by 202%, which indicated that it had better resilience and recyclability. In addition, the total pore area and porosity were increased to 16.24 m2/g and 88.43% from 5.46 m2/g and 2.11%, which provided more storage space for adsorption. The oil–water separation experiment showed that the adsorption capacity for most light oils was 11–13 g/g, and that for dichloromethane was as high as 40.5 g/g. After 10 adsorption–desorption cycles, the adsorption capacity only decreased from 15.6 to 14.5 g/g, which was still 93% of the initial adsorption capacity. H-SiO2 NPs/PUF represents good adsorption capacity, recyclability, and recyclability, so it as a carrier has a potential application in the treatment of marine oil spills. 相似文献
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M. Thirumal Dipak Khastgir Nikhil K. Singha B. S. Manjunath Y. P. Naik 《应用聚合物科学杂志》2008,108(3):1810-1817
Density is an important parameter that influences the properties and performances of rigid polyurethane foam (PUF). Rigid PUF with different densities were prepared by varying the amount of distilled water as blowing agent. This investigation reports the mechanical, morphological, water absorption, thermal conductivity, and thermal behavior of rigid PUF varying with the density, which controls the foam architecture. The density of the PUF decreased from 116 to 42 kg/m3 with an increase in the amount of water from 0.1 to 3.0 parts per hundred polyol by weight (phr), respectively. It was found that the mechanical properties of the PUFs changed with the foam density. The results of water absorption of the PUFs showed that water absorption increased with decrease in density, due to increase in the cell size and decrease in the cell‐wall thickness. The thermal conductivity measurements showed that the thermal conductivity decreased with increase in density. It was due to the decrease in cell size. The thermal analysis of the PUFs shows that the glass transition temperature increases with the decrease in foam density, but the thermal stability decreases with the decrease in foam density. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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To explore the potential of isocyanate usage reduction, water‐blown rigid polyurethane foams were made by replacing 0, 20, and 50% of Voranoll® 490 in the B‐side of the foam formulation by epoxidized soybean oil (ESBO) with an isocyanate index ranging from 50 to 110. The compressive strength, density, and thermal conductivity of foams were measured. The foam surface temperature was monitored before and throughout the foaming reaction as an indirect indication of the foaming temperature. Increasing ESBO replacement and/or decreasing isocyanate index decreased the foam's compressive strength. The density of the foam decreased while decreasing the isocyanate index to 60. Further decrease in isocyanate index resulted in foam shrinkage causing a sharp increase in the foam density. The thermal conductivity of foams increased while decreasing the isocyanate index and increasing the ESBO replacement. Mathematical models for predicting rigid polyurethane foam density, compressive strength, and thermal conductivity were established and validated. Similar to compressive strength, the foaming temperature decreased while decreasing the isocyanate index and increasing the ESBO replacement. Because of the lower reactivity of ESBO with isocyanate, the rate of foaming temperature decrease with decreasing isocyanate index was in the order of 0% > 20% > 50% ESBO replacement. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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Currently, the fabrication of microcell and bimodal cell structures (BCS) in polymer foams by using supercritical fluids has become a hot as well as a challenging research area worldwide. In this work, an environmentally friendly, effective, facile, and CO2-based foaming technique was presented to fabricate microcellular polypropylene (PP) foams with BCS via blending with thermoplastic polyurethane (TPU). The toughness, thermal properties, rheological properties, and foamability of PP were systematically investigated with gradual incorporation of TPU. Representative sea-island structure was observed in the scanning electron microscopy (SEM) images for the fracture surface of various PP/TPU samples. Rheological measurement results demonstrated that the viscoelasticity of various PP/TPU samples was improved remarkably compared with that of pure PP and pure TPU. The impact strength of various PP/TPU samples possessed the highest value as 12.4 kJ/m2 with the TPU content of 15 wt%. After the addition of TPU, an ameliorative cellular morphology was observed in the SEM micrographs of various PP/TPU samples and their volume expansion ratio was enhanced significantly thanks to their improved melt elasticity. Moreover, it is worth noting that BCS appeared in various PP/TPU foams when the TPU content exceeded 5 wt%. 相似文献
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蓖麻油型单组分聚氨酯发泡胶的制备 总被引:2,自引:0,他引:2
研究了以蓖麻油、聚醚多元醇、聚酯多元醇、PAPI为原料合成系列发泡单组分聚氯酯胶粘剂的工艺,研究了各因素对预聚体的合成、产品性能及贮存稳定性的影响。结果表明,异氰酸酯指数为28~30,蓖麻油为多元醇总质量的40%,预聚催化剂为T-12,固化催化剂为吗啉类和LX-1,溶剂为乙酸乙酯和二氧甲烷,在70-80℃下反应3h,得到符合建材工业要求的产品。 相似文献
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One‐step manufacturing process (in‐situ foaming) provide great potential for the production of foam core panels. Polyurethane (PU) foam showed good applicability for use for in‐situ foaming. Here, the effect of ingredient ratios of rigid PU foam on foam performance and panel properties is investigated. It was observed that the isocyanate (ISO) content and polyols (PO) type and content significantly change the foam and panel properties. Foam cell density, as the most important factor influencing the foam characteristics, was higher in foams with higher ISO and polyether content. Bending strength, internal bond and screw withdrawal resistance of the foam core panels were significantly enhanced when the ISO and polyether content was increased in the foam formulation. Varying the ISO content had no influence on panel properties with higher content of polyester (60%) in the PO blend. Varying the foam ingredient ratios did not change the thickness swelling, while the water absorption was dependent on the foam components ratios. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44722. 相似文献
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以聚己内酯(PCL)为基体,添加不同含量聚乳酸(PLA)熔融共混制备具有不同分散相形态的PCL/PLA共混物,利用超临界二氧化碳(scCO2)微孔发泡工艺制备不同发泡倍率和开孔率的PCL/PLA多孔材料用于吸油应用。针对边长3 mm正方体样品溶解度实验发现100 min后CO2在PCL中已达到饱和吸附状态。PLA分散相含量的增加显著增大了PCL/PLA共混物泡孔密度,并使共混泡孔尺寸减小且分布更加均匀;发泡温度升高6℃,泡孔尺寸增大50%,发泡倍率增大38%,开孔率减小了20%。PCL/PLA开孔材料具有明显的亲油疏水性,发泡倍率越高,疏水性越好;针对花生油和硅油的吸油实验发现材料吸油率与发泡倍率和开孔率整体呈正比,实际吸油量高于理论计算值,10次循环吸油测试后样品吸油率仅降低8.5%,材料吸油量与油品特性黏度关系不大。 相似文献
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The reactions between polymeric diphenyl methane diisocyanate (polymeric MDI) and conventional polyols to produce foamed polyurethane products are well documented and published. Current polyurethane foams are predominantly produced from these reactions whereby the polyol components are usually obtained from petrochemical processes. This article describes a new development in polyurethane foam technology whereby a renewable source of polyol derived from refined–bleached–deodorized (RBD) palm oil is used to produce polyurethane foams. Using very basic foam formulation, rigid polyurethane foams were produced with carbon dioxide as the blowing agent generated from the reaction between excess polymeric MDI with water. The foams produced from this derivatized RBD palm oil have densities in excess of 200 kg/m3 and with compression strengths greater than 1 MPa. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 509–515, 1998 相似文献
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以环氧丙烷聚醚多元醇、苯酐聚酯多元醇、多苯基甲烷多异氰酸酯PM-200、发泡剂一氟二氯乙烷(HCFC-141b)、泡沫稳定剂硅油AK-8801等为主要原料,采用一步法合成了聚氨酯硬泡,考察了不同种类多元醇及其配比、发泡剂、泡沫稳定剂种类及用量等对聚氨酯硬泡抗压性能的影响。结果表明:高羟值、高官能度的环氧丙烷聚醚多元醇可提高泡沫的压缩强度,且当环氧丙烷聚醚多元醇4110为100份,并加入20份左右苯酐聚酯多元醇580及10份左右聚醚403,泡沫稳定剂用量1~2份,发泡剂水用量0.5~1份,HCFC-141b用量30~35份,催化剂用量0.5~1.5份时,所得聚氨酯硬泡性能较好。 相似文献
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Both HCFC‐ and pentane‐blown rigid polyurethane foams have been prepared from polyols derived from soybean oil. The effect of formulation variables on foam properties was studied by altering the types and amounts of catalyst, surfactant, water, crosslinker, blowing agent, and isocyanate, respectively. While compressive strength of the soy foams is optimal at 2 pph of surfactant B‐8404, it increases with increasing the amount of water, glycerin, and isocyanate. It also increases linearly with foam density. These foams were found to have comparable mechanical and thermoinsulating properties to foams of petrochemical origin. A comparison in the thermal and thermo‐oxidative behaviors of soy‐ and PPO‐based foams revealed that the former is more stable toward both thermal degradation and thermal oxidation. The lack of ether linkages in the soy‐based rather than in PPO‐based polyols is thought to be the origin of improved thermal and thermo‐oxidative stabilities of soy‐based foams. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 467–473, 2000 相似文献
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聚氨酯有机硅匀泡剂的研究及应用 总被引:3,自引:0,他引:3
综述了近年来有机硅表面活性剂聚二甲基硅氧烷、聚醚改性聚硅氧烷作为聚氨酯泡沫塑料匀泡剂的研究进展,重点介绍了其主要品种S i─C型聚醚改性聚硅氧烷在无溶剂工艺、催化剂的制备及聚醚配方优化等方面的进展,指出目前提高国产软泡匀泡剂的产品质量是聚氨酯有机硅匀泡剂研究的发展方向。 相似文献