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1.
C. K. Lyon Vilma H. Garrett Leo A. Goldblatt 《Journal of the American Oil Chemists' Society》1961,38(5):262-266
The preparation of trichlorofluoromethane-blown rigid urethane foams using toluenediisocyanate and castor oil-derived polyols
was investigated. The castor-based polyols included castor oil, hydroxylated castor oil, technical glycerol-, penta-erythritol-,
and sorbitol monoricinoleates, and N,N-bis(2-hydroxyethyl) ricinoleamide.
The last of these yielded the best foams when used as the sole polyol component added to the prepolymer. However better foams
were obtained by using, as the polyol component, a mixture of a castor oil-derived polyol and a lower-molecular-weight polyol
with a higher hydroxyl content. These polyol mixtures yielded more highly cross-linked polymers and hence foams with higher
compressive strengths and less tendency to shrink after foaming.
The effect of catalyst, silicone surfactant, and trichlorofluoromethane content was also investigated. An empirical relationship
between density and compressive strength in a given foam system was derived.
Presented at the fall meeting, American Oil Chemists' Society, New York, October 17–19, 1960.
A laboratory of the Western Utilization Research and Development Division. Agricultural Research Service, U.S. Department
of Agriculture. 相似文献
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Suresh S. Narine Xiaohua Kong Laziz Bouzidi Peter Sporns 《Journal of the American Oil Chemists' Society》2007,84(1):65-72
Rigid polyurethane (PU) foams were prepared using three North American seed oil starting materials. Polyol with terminal primary
hydroxyl groups synthesized from canola oil by ozonolysis and hydrogenation based technology, commercially available soybean
based polyol and crude castor oil were reacted with aromatic diphenylmethane diisocyanate to prepare the foams. Their physical
and thermal properties were studied and compared using dynamic mechanical analysis and thermogravimetric analysis techniques,
and their cellular structures were investigated by scanning electron microscope. The chemical diversity of the starting materials
allowed the evaluation of the effect of dangling chain on the properties of the foams. The reactivity of soybean oil-derived
polyols and of unrefined crude castor oil were found to be lower than that of the canola based polyol as shown by their processing
parameters (cream, rising and gel times) and FTIR. Canola-PU foam demonstrated better compressive properties than Soybean-PU
foam but less than Castor-PU foam. The differences in performance were found to be related to the differences in the number
and position of OH-groups and dangling chains in the starting materials, and to the differences in cellular structure. 相似文献
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Fifty vegetable oil‐based polyols were characterized in terms of their hydroxyl number and their potential of replacing up to 50% of the petroleum‐based polyol in waterborne rigid polyurethane foam applications was evaluated. Polyurethane foams were prepared by reacting isocyanates with polyols containing 50% of vegetable oil‐based polyols and 50% of petroleum‐based polyol and their thermal conductivity, density, and compressive strength were determined. The vegetable oil‐based polyols included epoxidized soybean oil reacted with acetol, commercial soybean oil polyols (soyoils), polyols derived from epoxidized soybean oil and diglycerides, etc. Most of the foams made with polyols containing 50% of vegetable oil‐based polyols were inferior to foams made from 100% petroleum‐based polyol. However, foams made with polyols containing 50% hydroxy soybean oil, epoxidized soybean oil reacted with acetol, and oxidized epoxidized diglyceride of soybean oil not only had superior thermal conductivity, but also better density and compressive strength properties than had foams made from 100% petroleum polyol. Although the epoxidized soybean oil did not have any hydroxyl functional group to react with isocyanate, when used in 50 : 50 blend with the petroleum‐based polyol the resulting polyurethane foams had density versus compressive properties similar to polyurethane foams made from 100% petroleum‐based polyol. The density and compressive strength of foams were affected by the hydroxyl number of polyols, but the thermal conductivity of foams was not. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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New polyols of high hydroxyl content and reactivity were made from linseed and soybean oils and acids by catalytic carboxylation
followed by reaction with diethanolamine. Urethane foams made with these diethanolamides were stronger than those made with
castor oil at equivalent polyol wt. Because of their higher hydroxyl content, a larger amount of diethanolamides could be
incorporated in foam formulations than is possible with castor oil. The rigid urethane foams prepared with the new polyols
meet the requirements of commercial products with respect to density, compressive strength, and dimensional stability.
National Flaxseed Processors Association Fellow, 1969–1973. Present address: Avery Products, Technical Center, 325 North Altadena
Dr., Pasadena, CA 91107. 相似文献
8.
A. Ehrlich M. K. Smith T. C. Patton 《Journal of the American Oil Chemists' Society》1959,36(4):149-154
Summary A systematic investigation of some 21 castor polyols as base materials for preparing urethane foams was carried out. Prepolymers
were prepared both from individual castor polyols and from mixtures of them with an anhydrous castor oil. Foams formed from
these prepolymers were checked for shrinkage on cure, density, and modulus.
From the wide range of results obtained it is evident that castor polyols can serve as effective urethane components. Aside
from serving as major polyols for reaction with di-isocyanates, they can also be used as modifying polyols a) to speed up
prepolymer preparation, b) to adjust prepolymer viscosity to any required degree, c) to minimize loss of modulus on humid
aging, and as cross-linking centers with negligible loss of foam modulus. Details covering the preparation of a nonshrinking,
semi-rigid, light-weight urethane foam based on an 85% anhydrous castor oil/15% epoxidized castor oil mix are outlined in
the article.
Presented at the Spring Meeting, American Oil Chemists' Society, Memphis, Tenn., April 20–23, 1958. 相似文献
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Flexible polyurethane foams synthesized employing recovered polyols from glycolysis: Physical and structural properties
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Polyurethane (PU) is one of the most important polymers with a global production of 17.565 million tons, which makes its recycling an urgent task. Besides, the main goal of PU recycling is to recover constituent polyol as a valuable raw material that allows to obtain new PU with suitable properties. Split‐phase glycolysis can be considered the most interesting PU recycling process since provides high‐quality recovered products in terms of polyol purity. The aim of this work was to evaluate several recovered polyols as replacement of the raw flexible polyether polyol in the synthesis of new flexible PU foams. These recovered polyols come from the split‐phase glycolysis of different types of PU foams and employing as cleavage agents diethylene glycol or crude glycerol (biodiesel byproduct). The influence of the foam waste type and of the cleavage agent on the foams properties was analyzed. The recovered polyols were evaluated by performing several foaming tests according to the method of free expansion foaming of conventional flexible foam. Synthesized flexible foams containing different proportions of recovered polyols were characterized by means of scanning electron microscopy, density and tensile properties; obtaining similar and sometimes even better values compared to the foams manufactured from commercial polyols. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45087. 相似文献
11.
Aruna Palanisamy 《Polymer Composites》2013,34(8):1306-1312
The present work deals with the development of polyurethane–clay nanocomposite foams by replacing part of the synthetic polyol with castor oil derivative. Hydroxylated castor oil was converted into diethanol amide by transamidation and the resulting polyol was formulated into water‐blown foams. Modified montmorillonite clay was used as nanofiller in different amounts viz. 0.5%, 1.0%, 2.0%, and 5.0% by total weight of the foam formulation. Rheological measurements on the polyol–clay mixtures indicated that up to 1% clay loading there is no significant change in the viscosity with shear rate and beyond 2%, shear thinning occurred. X‐ray diffraction studies further substantiated these results. The effect of the modified clay on the density, mechanical properties such as compression strength, compression modulus, and microstructure of the foams were investigated. The filler thus added had a reinforcing effect on the foam as observed in the density and compression strength measurements. Differential scanning calorimetric studies on Tg and dynamic mechanical analyses on the modulus clearly indicated that 1% clay loading and above led to exfoliation and plasticizing effect. Exfoliated nanocomposites in compositions containing 1% clay and more yielded a much higher nucleation rate than intercalated ones leading to reduced cell size as observed by optical and scanning electron microscopy. Thus, castor oil, which is readily available, relatively inexpensive, and environmentally benign nonedible oil, has been successfully used to prepare filled semirigid foams which can find application in insulation and packing. POLYM. COMPOS. 34:1306–1312, 2013. © 2013 Society of Plastics Engineers 相似文献
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Natural Palm Olein Polyol as a Replacement for Polyether Polyols in Viscoelastic Polyurethane Foam
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H. Nurul ‘Ain T. I. Tuan Noor Maznee M. N. Norhayati M. A. Mohd Noor S. Adnan P. P. Kosheela Devi S. Mohd Norhisham S. K. Yeong A. H. Hazimah Irma Campara Vahid Sendijarevic Ibrahim Sendijarevic 《Journal of the American Oil Chemists' Society》2016,93(7):983-993
The impact of replacing three polyether polyols with different levels of a single palm olein‐based natural oil polyol (NOP) was systematically correlated with the changes in foaming reactivity, cell structure, physico‐mechanical properties, and morphology of viscoelastic (VE) foams. The data show that replacing the polyether polyols with the NOP slightly increased the rate of the foaming reactivity. Increasing the NOP content resulted in increased cell size and cells remained fully open. Increased NOP content contributed to higher load bearing properties of VE foam, which can be attributed to higher functionality of NOP compared to polyether polyols. Addition of the NOP slightly increased the resilience of the foams, however, the hysteresis which is the measure of energy absorption remained mostly unaffected. Age properties, characterized by dry and humid compression sets, were mostly unaffected by the replacement of the polyether polyol with the NOP. The addition of NOP did not impact the morphology of the VE foam polymer matrix, which appears to retain a low degree of hard and soft segment domain separation. Overall, the results demonstrate a feasibility that the NOP can be used to partially replace the polyether polyols in VE polyurethane foams without significant impact on the functional performance. 相似文献
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Lorenzo Indennidate Donato Cannoletta Francesca Lionetto Antonio Greco Alfonso Maffezzoli 《Polymer International》2010,59(4):486-491
The use of polyether polyols is common in polyurethane industry, particularly in soft PU applications. In particular, viscoelastic foams, characterized by slow recovery after compression, are obtained using poly(ethylene oxide) (PEO) polyols. Nanofilled polyols can be used for the production of viscoelastic foams with improved fire resistance properties. The high polarity of polyether polyols is responsible of a poor affinity with the organic modifiers used in commercial organically modified montmorillonite (omMMT). In this work, organically modified montmorillonites were prepared, having an improved affinity with the polyether polyols used for the production of soft PU foams. The montmorillonite was modified by using polyetheramines with different ethyleneoxide/propyleneoxide amounts. A strongly intercalated/exfoliated structure was obtained after mixing the polyol with the omMMT. The viscosity increased by three orders of magnitude and the diffraction angles of the MMT measured by x‐ray analysis decreased to values lower than 1.5°. The intercalated structure was preserved after the curing stage, when the isocyanate was added to the polyol/omMMT. The resulting polyurethane had an irregular open cell structure, and was characterized by a mechanical properties comparable to those of unfilled polyurethane. Copyright © 2009 Society of Chemical Industry 相似文献
14.
This study investigated the physical properties of water‐blown rigid polyurethane (PU) foams made from VORANOL®490 (petroleum‐based polyether polyol) mixed with 0–50% high viscosity (13,000–31,000 cP at 22°C) soy‐polyols. The density of these foams decreased as the soy‐polyol percentage increased. The compressive strength decreased, decreased and then increased, or remained unchanged and then increased with increasing soy‐polyol percentage depending on the viscosity of the soy‐polyol. Foams made from high viscosity (21,000–31,000 cP) soy‐polyols exhibited similar or superior density‐compressive strength properties to the control foam made from 100% VORNAOL® 490. The thermal conductivity of foams containing soy‐polyols was slightly higher than the control foam. The maximal foaming temperatures of foams slightly decreased with increasing soy‐polyol percentage. Micrographs of foams showed that they had many cells in the shape of sphere or polyhedra. With increasing soy‐polyol percentage, the cell size decreased, and the cell number increased. Based on the analysis of isocyanate content and compressive strength of foams, it was concluded that rigid PU foams could be made by replacing 50% petroleum‐based polyol with a high viscosity soy‐polyol resulting in a 30% reduction in the isocyanate content. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
15.
C. K. Lyon Vilma H. Garrett L. A. Goldblatt 《Journal of the American Oil Chemists' Society》1964,41(1):23-25
Solvent-blown rigid urethane foams prepared from a low-cost polyol mixture composed of raw castor oil and triisopropanolamine
have been described. Foams with higher compressive strengths can be obtained by substituting oxidized (blown) castor oil for
the raw castor oil in formulations of this type.
The properties of rigid foams prepared from several commercial blown castor oils are described. The properties of these foams
are correlated with the degree of oxidation of the blown oils used, as indicated by their oxygen content, density, viscosity,
and refractive index. Removal of acid from blown oils having high acid values has no significant effect on the compressive
strength of foams prepared from these oils.
When blown castor oil is used instead of raw castor oil, less isocyanate is required to produce a urethane foam of specified
density and compressive strength.
Presented at the AOCS meeting in Toronto, Canada, 1962.
A laboratory of the W. Utiliz. Res. & Dev. Div., ARS, U.S.D.A. 相似文献
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阻燃性软质聚氨酯泡沫塑料的研制 总被引:4,自引:1,他引:4
以自制的聚醚多元醇为原料,加入经粉碎并表面处理的三聚氰胺和阻燃剂T201制得阻燃性软质聚氨酯泡沫塑料。系统地考察了配方中的两种阻燃剂用量,特种聚醚多元醇和泡沫密度对泡沫塑料阻燃性和物理性能的影响。 相似文献
18.
The effect of different palm oil‐based bio‐polyols on foaming process and selected properties of porous polyurethanes
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Norma E Marcovich Maria Kurańska Aleksander Prociak Elżbieta Malewska Sonia Bujok 《Polymer International》2017,66(11):1522-1529
Rigid polyurethane foams were successfully prepared by blending up to 70 wt% of two different palm oil‐based bio‐polyols with a petrochemical polyether polyol. The bio‐polyols were synthesized by epoxidation–oxirane ring‐opening process using water (PP102) and diethylene glycol (PP147), respectively. Due to the high viscosity of both bio‐polyols the reactive mixture was heated to start the foaming reaction at about 50 °C. Under these conditions, the gelling reactions speed up as the amount of PP147 increases but slow down to a great extent when PP102 is used. The thermal conductivity of modified foams is higher and the closed cell content lower compared to reference ones, even when the bio‐foams present a lower apparent density. However, all foams exhibit reduced water absorption, excellent dimensional stability and better thermal stability at temperatures up to 400 °C than the control foam. Conversely, their mechanical and dynamic mechanical properties become poorer as the PP147 concentration increases and even more so if PP102 is used instead. PP147 foams containing up to 50% bio‐polyol could be used as a green replacement of petroleum‐based ones in applications where excellent behaviour in compression (the most affected properties) is not fundamental, with the additional advantages of reduced density and increased content of bio‐derived components. © 2017 Society of Chemical Industry 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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The preparation and characteristics of rigid polyurethane foams (RPUFs) based on recycled polyol obtained by glycolysis of waste RPUF scraps from end-of-life refrigerators were investigated. To deactivate the amine adducts derived from isocyanates, the recycled product obtained after depolymerization was chemically modified via addition polymerization of propylene oxide. Two kinds of recycled polyols with different hydroxyl values and viscosity were blended with conventional virgin polyether polyol to prepare the RPUFs. The effects of the recycled polyols on the physical properties of RPUFs such as cell structures, compressive strength, thermal conductivity, and limiting oxygen index were discussed. It was found that the RPUFs from recycled polyols showed superior compressive strength, thermal insulation property, and self-extinguishing property compared with conventional control foam. The results of this study reveal that the recycled polyols could be used as feedstock for RPUFs with superior performance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47916. 相似文献