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1.
以生物质基粗甘油为主要原料,采用一锅法合成粗甘油基多元醇,进一步发泡制备了聚氨酯泡沫材料。在此基础上,利用甲基三氯硅烷对泡沫材料进行疏水改性,制备出改性聚氨酯吸油材料。采用傅里叶红外光谱仪、扫描电镜和热重分析对改性前后泡沫的结构形貌、热稳定性和接触角进行表征,测试了改性聚氨酯吸油材料吸油性能。结果表明:经疏水改性后在泡沫表面合成了聚硅氧烷,水接触角由130°增大至140°,提高了吸油材料疏水性能。改性聚氨酯吸油材料对乙醇、甲醇、氯仿等8种有机物的吸附量范围为16.7~45.2 g/g。经循环使用50次后,吸油材料对柴油和大豆油的吸附量分别为最高吸附量的95.8%和97.6%,表现出优异的吸油性能。  相似文献   

2.
The modulus development of reacting polyurethane foams from modified soy oil (soy polyol) was studied. The reaction and buildup of rheological properties were monitored using vane geometry in a strain‐controlled rheometer. Normal force exerted on the vanes by the expanding foam was measured as a function of time to study the phenomenon of cell opening. The effect of foam ingredients and process parameters on the modulus development was investigated. The morphology of the cured foam was studied using scanning electron microscope (SEM). Experiments were carried out to elucidate the effect of water and addition of petroleum‐based polyol on the modulus development of the reacting foam and the morphology of the cured product. The effect of frequency and thermal history on the modulus development of the reacting foam was also studied. Ozonolysis of soybean oil was carried out to study the effect of adding OH groups on the modulus development during the foaming reaction. Four stages of modulus development, similar to those observed for synthetic polyol (voranol, Aldrich Chemicals) foams, were observed. Increase in water content led to an earlier stiffening of the polymer and a higher modulus. Addition of voranol in soy polyol reduced the liquid foam plateau and significantly reduced the reaction time. Ozonolysis of soy oil led to an earlier phase separation as compared with foams from soy polyol. The temperature at which the foaming reaction takes place dominated the rate of modulus buildup. Higher texture (urea aggregates) and an increase in the cell size were observed with an increase in water content for soy polyol foams. Addition of voranol increased the number of open cells. Polym. Eng. Sci. 44:1977–1986, 2004. © 2004 Society of Plastics Engineers.  相似文献   

3.
A new jet-cooked starch—oil composite has been blended with a polyester polyol and then reacted with isocyanate to give a polyurethane foam. Infrared spectroscopy and microscopy have been used to examine the resultant products. Infrared spectra have shown the products contain the urethane structures and light and electron microscopy have shown the differences in the cell wall structures and networks of the foams when compared to the control foams. Inclusion of the starch—oil composite in the formulation resulted in increased viscosity of the reaction mixture as well as a more irregular cellular structure and a rougher texture of the cured foam. Larger cells were more abundant and there was more evidence of tearing during expansion. The scanning electron photomicrographs show the open-cell structure of both the control and blended foams and their reticular network, which is more uniform in the control. This examination provides insight into the foaming process and provides information to make the necessary adjustments for acquiring the desired polymeric product. Incorporation of the starch—oil composite in polyurethane foams provides a new dimension of possibilities for enhancing their physical, functional, and environmental properties. © 1997 John Wiley & Sons, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America.
  • J Appl Polym Sci 64: 1355–1361, 1997  相似文献   

    4.
    以聚乳酸(PLA)为基体,添加不同含量聚氨酯(TPU)熔融共混制备具有不同相形态的PLA/TPU共混物,基于超临界二氧化碳(scCO2)微孔发泡工艺,研究不同发泡温度下PLA/TPU复合多孔材料泡孔结构、发泡倍率和开孔率对样品吸油性能的影响。结果表明,随着TPU含量从10 %(质量分数,下同)增加到50 %,共混物从典型的“海?岛”相形态转变为部分共连续相形态,PLA基体黏弹性提升,结晶能力下降;PLA70组分发泡后泡孔结构更为均匀,随着发泡温度的增加,泡孔尺寸和发泡倍率先增大后减小,在94 ℃发泡温度下发泡样品发泡倍率达到29.1倍,最大开孔率75 %;TPU的加入显著增加了PLA基体的弹性回复能力,94 ℃发泡温度下的发泡样品具有最大的抗压强度,永久形变量最小;针对硅油和环己烷的吸油测试发现对硅油的吸油量大于环己烷,发泡材料的吸油量与发泡倍率和开孔率的乘积成正比,针对硅油单次最大吸油量为10.4 g/g。  相似文献   

    5.
    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   

    6.
    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   

    7.
    变压发泡工艺对聚氨酯泡沫泡孔结构控制的研究   总被引:2,自引:0,他引:2  
    利用变压发泡可实现对聚氨酯泡沫泡孔结构的控制,得到气孔细密均匀的泡沫体。主要探讨了变压发泡工艺下,恒压时间、压力大小对泡沫泡孔结构的影响  相似文献   

    8.
    This paper examines the effect of foam density, oil viscosity, and temperature on the oil sorption behavior of polyurethane foams. Four polyurethane foams with different densities and two oil types with different viscosities were investigated. The amount of oil uptake was measured gravimetrically. Oil transport through the foams was analyzed by nondestructive X‐ray microtomography. Oil sorption capacity increased significantly with the decrease in foam density, due to the increase in the number of open cells. The oil sorption capacity depended only slightly on sorption temperature and oil viscosity. X‐ray visualization allowed pore filling behavior to be observed directly, and further scope to extend the technique is revealed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 360–367, 2006  相似文献   

    9.
    We describe a method developed to quantify the amount of foam in frying oils. In this method the foam was quantified by digitizing photographic images that were taken continuously at 1-s intervals; spots showing more than a certain luminance were considered as foam. The ratio of total foaming area to the whole oil surface was integrated to obtain the intergration of foam (IF) index as a parameter of the extent of foaming. There was a good correlation between this method and the visual evaluation done by a group of panelists. Furthermore, the foaming tendency correlated with the distribution of TG by M.W. when the IF was plotted against the foam index of TG (FIT), which reflects the M.W. distribution. A correlation was found between the FIT value of oil and foaming on frying, indicating that when the FIT value is small, the oil foams less. Based on the results of this investigation, we have designed a method to obtain edible oils consisting of medium-chain FA that not only are nutritious but also have good cooking properties.  相似文献   

    10.
    以大豆分离蛋白、高活性聚醚、聚合物多元醇、交联剂、发泡剂、泡沫稳定剂和混合异氰酸酯为原料,自由发泡、常温熟化制备了大豆蛋白基高回弹聚氨酯软泡。研究了大豆蛋白质(SPI)对聚氨酯泡沫物理性能、力学性能、孔结构和热性能的影响。结果表明:SPI添加量对泡沫物理和力学性能影响最大。随着SPI含量增加,泡沫的密度、尺寸稳定性提高,压陷硬度和舒适因子提高增大;回弹率下降,断裂伸长率减小,而拉伸强度先增大后减小。SPI能够提高聚氨酯的热稳定性,但最好低于150℃使用。  相似文献   

    11.
    王学晨  由明  张兴祥  李伟 《聚氨酯工业》2011,26(4):17-20,28
    将密胺树脂包覆正十八烷形成的微胶囊化相变材料( MicroPCMs)引入聚氨酯软质泡沫,研究该MicroPCMs的热处理条件对聚氨酯复合泡沫制备以及其加入对泡沫结构、压缩性能、A组分体系粘度的影响.结果表明,MicroPCMs经过适当热处理后,可减小其对发泡的不利影响.MicroPCMs聚氨酯高回弹泡沫的泡孔孔径减小,...  相似文献   

    12.
    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   

    13.
    大型模胎用硬质聚氨酯泡沫塑料的制备研究   总被引:1,自引:1,他引:0  
    研究了大型模胎用硬质聚氨酯泡沫塑料的制备方法,考察了催化剂用量、匀泡剂用量、物理发泡剂用量、化学发泡剂、模具压力、后处理温度等对硬质聚氨酯泡沫塑料泡体结构和性能的影响。结果表明,可以通过控制催化剂三乙醇胺和有机锡的用量配比来调节发泡和凝胶速率,匀泡剂用量、物理发泡剂用量、化学发泡剂、模具压力、后处理温度等均能对泡体结构和性能产生影响。  相似文献   

    14.
    采用化学交联模压法制备了丙烯腈-苯乙烯-丁二烯共聚物(ABS)微孔发泡材料,研究了发泡温度、发泡压力及发泡时间对ABS微孔发泡材料气体的扩散行为及泡孔结构的影响,结果表明:气体吸收量随着发泡温度、发泡压力和发泡时间的增加,先增大后减小;随着气体吸收量的增加,制品的泡孔尺寸逐渐减小,泡孔密度逐渐增大,增加气体吸收量有利于提高发泡效果。当发泡温度为170℃、发泡压力为10 MPa、发泡时间为12min时,泡孔密度约为2.87×108个/cm3,可满足工业上微孔发泡材料泡孔密度的要求。  相似文献   

    15.
    为降低水对聚氨酯发泡材料性能的影响,向聚氨酯发泡材料中添加了γ-(2,3-环氧丙氧)丙基三甲氧基硅烷(KH-560).并利用TG、SEM、IR研究了添加硅烷偶联剂前后聚氨酯发泡材料吸水情况,最终研究出发泡材料阻水的机理.TG的结果表明,加入KH-560后,聚氨酯发泡材料的吸水性大大降低.在偶联剂的添加量为3%时,泡孔结...  相似文献   

    16.
    A dry starch–oil composite was blended with each of three glycols; ethylene, polyethylene, and propylene, and then reacted with isocyanate to produce polyurethane foams. The liquid glycols permitted the dry composite to blend well with the other ingredients in the foam formulations. Infrared spectra confirmed the presence of urethane structures in the composite–glycol foams. Polyethylene glycol provided a slightly less dense foam than the other glycols in the composite–glycol products. Microscopy showed a greater number of larger cells in the composite–polyurethane glycol foams. Infrared spectra indicated essentially no qualitative differences in the composite–glycol foams with the three glycols. By prestaining starch with toluidene blue and oil with sudan red, the location of the starch and oil components of the milled composite were observed in the composite–propylene glycol foam. Intact flakes of the composite were observed in the foam. An apparent loss of mobility of oil in the composite–polyurethane foam, as evidenced by NMR analysis, is probably due to crosslinking by isocyanate diffusing into the flakes. Both the cell structure and uniformity of blending were improved by using these glycols rather than the polyester polyol described previously. J Appl Polym Sci 69: 957–964, 1998. Published 1998 John Wiley & Sons, Inc.  相似文献   

    17.
    Modified soy‐based vegetable oil polyols were successfully incorporated as a replacement for conventional polyols to produce flexible slabstock polyurethane foams. The oil was characterized for its hydroxyl value and fatty acid composition. The modified oils had higher hydroxyl values and lower unsaturated acids than regular unmodified oils. Three different modified polyols were used to investigate the reactivity with isocyanates. The effects on the foaming reaction of two different isocyanates, namely TDI and MDI, were investigated. The reactions were also carried out with a mixture of polyols containing synthetic polyols and vegetable oil‐based polyols to delineate the effect of each component. FTIR technique was used to identify the sequence of chemical reactions during the foaming process. The effect of water levels and isocyanate content on the kinetics of the foaming reaction was investigated. Information regarding the formation of hard and soft segments with the varying compositions was obtained. As the water content increased, the amount of the hard segment and urea formation increased in both soy oil polyols and synthetic polyols. Increased synthetic polyols in the mixture increased the rate of reaction and phase mixing due to the availability of primary hydroxyl groups. Scanning electron microscopy (SEM) and small‐angle X‐ray scattering (SAXS) were used to probe the morphology. As the water content increased, the cell size increased. At lower water content a more uniform cell structure was evident and at higher water levels hard domain size increased. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3097–3107, 2002  相似文献   

    18.
    研究了体系中起泡剂和稳泡剂的吸附量并通过岩心流动实验,测定了起泡剂和稳泡剂在含油、不含油条件下的滞留量。研究结果表明,稳泡剂的吸附等温线呈“L”型,油砂上的饱和吸附量小于石英砂上的饱和吸附量;起泡剂的吸附等温线呈典型的“S”型,油砂表面上的吸附量总是小于在石英砂表面上的吸附量;稳泡剂和起泡剂的动态吸附量都小于在岩心砂上的静态吸附量,化学剂在含油岩心中的滞留量小于不含油岩心中的滞留量。  相似文献   

    19.
    为研究CO2驱油田分离器内泡沫层产生及消除机理,设计了一套高压溶气原油泡沫测试系统,采用降压法研究了CO2-原油体系的发泡特性。利用高速摄像机对泡沫产生至衰变的演变过程进行了记录,总结分析了不同降压阶段的气泡行为,研究了降压速率和搅拌速率对原油发泡特性的影响规律。研究发现,随压力降低,稳定存在气泡的直径增大,气泡位置上移,发泡行为更加剧烈;降压速率增加对降压阶段的发泡行为无明显影响,但会加剧稳定工作压力下的发泡行为;在转速小于等于120 r/min的条件下,搅拌速率增加会加剧降压阶段的发泡行为,但会加速稳定工作压力下的泡沫衰变。  相似文献   

    20.
    Foam stability and segmented polymeric phase morphology of polyurethane foams synthesized partially and completely from castor oil are investigated. Preliminary analysis of the impact of alterations in the polymeric phase on macroscopic stress dissipation in foams is also carried out. The stability and morphology show unique trends depending on the concentration of castor oil used in foam synthesis. While low and intermediate concentrations of castor oil does not significantly affect the foaming process; at high concentrations, the volumetrically expanding liquid matrix remains in a nonequilibrium state during the entire foaming period, resulting in significant foam decay from top. This increases the final foam cell density and decreases the plateau border thickness at bottom. In the polymeric phase of castor oil based foams, the fraction of monodentate urea increases at the cost of non‐hydrogen bonded urea. These monodentate urea domains undergo flocculation in foams synthesized completely from castor oil, thus prominently modifying the segmented morphology. The glass transition temperature of soft segments of partially substituted foams shows moderate increase, with indications of phase mixing between the polyether and castor oil generated urethane domains. Foams synthesized entirely from castor oil have significant sol fraction due to unreacted oligomers. The microscopic alterations in polymeric phase reduce the elastic recovery of partially substituted castor oil foams compared to its viscous dissipation under an applied stress. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40668.  相似文献   

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