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制备了酚醛泡沫和聚氨酯泡沫,并研究了酚醛硬泡与聚氨酯硬泡的热稳定性及燃烧性能。结果表明:和聚氨酯泡沫比较,酚醛泡沫的热失重小,热释放速率和热释放总量低。因此酚醛泡沫的热稳定性和阻燃性能明显优于聚氨酯泡沫。 相似文献
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将聚碳酸酯二元醇(PCDL)作为配方组分,采用直接添加和将PCDL与异氰酸酯合成预聚体后再添加的不同工艺,制备了聚碳酸酯型聚氨酯微孔泡沫,并分别与普通聚氨酯微孔泡沫进行了对比.结果表明,聚碳酸酯型聚氨酯微孔泡沫的力学性能比普通聚氨酯微孔泡沫有所提高;PCDL预聚体制备的聚氨酯微孔泡沫材料耐热老化性能最佳. 相似文献
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硬质聚氨酯泡沫经常出现组合聚醚和异氰酸酯混合后不发泡、硬质聚氨酯泡沫收缩、硬质聚氨酯泡沫酥脆、硬质聚氨酯泡沫太软,熟化过慢、硬质聚氨酯泡沫塌泡、硬质聚氨酯泡沫开裂或中心发焦(烧心)等质量通病,影响制品的性能和使用。本文对硬质聚氨酯泡沫质量通病产生的原因以及防治措施进行了简略分析。 相似文献
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本文主要提出了生产药用香料聚氨酯泡沫的工艺配方及试制方法,论述了香精对聚氨酯泡沫成形工艺的影响,定香剂对留香时间的控制,药用香料泡沫的药理作用及其应用。 相似文献
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醇-磷酸酯法降解废旧聚氨酯的研究 总被引:2,自引:0,他引:2
选用不同的降解剂,采用醇-磷酸酯法降解废旧聚氨酯泡沫,对降解产物进行性能测试。结果表明:以一缩二乙二醇和磷酸三正丁酯为降解剂降解聚氨酯软质泡沫效果较好。以降解产物作为部分原料制备聚氨酯硬质泡沫塑料体,对其性能测试并与不加降解产物制备的聚氨酯硬质泡沫体比较,结果表明:降解产物作为部分原料对聚氨酯硬质泡沫塑料的性能影响不大。 相似文献
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对聚氨酯泡沫材料与聚苯乙烯泡沫材料在室内设计中的应用进行对比。结果表明:随着密度的增加,聚氨酯泡沫材料和聚苯乙烯泡沫材料的压缩强度均逐渐提高,当两种材料密度相同时,聚氨酯泡沫材料的压缩强度略低于聚苯乙烯泡沫材料;随着密度的增加,聚苯乙烯泡沫材料的导热率逐渐增大,聚氨酯泡沫材料的导热率先减小后增大。采用一氟三氯甲烷作为聚氨酯泡沫材料的发泡剂,其导热率明显低于聚苯乙烯泡沫材料,在保温效果上优势显著。当处于相同的吸水条件,聚氨酯泡沫的保温性能更优异。仿真分析表明,使用聚氨酯泡沫材料较聚苯乙烯泡沫材料的节能效果更明显。 相似文献
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介绍了用二氯甲烷替代氟里昂生产聚氨酯泡沫塑料的方法,并对两种发泡剂生产的聚氨酯泡沫的性能和经济效益进行了比较。 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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杜建科 《现代塑料加工应用》2000,(2)
分析了软质聚氨酯泡沫塑料的难燃化技术 ,重点讨论了影响泡沫体阻燃性能的因素 ,认为理想的阻燃处理方法和配方应该是在材料各项性能间寻求最佳的综合平衡 ,同时根据材料的具体使用要求确定其合理的阻燃级别 相似文献
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Rigid halogen‐free and flame‐retarding polyurethane foams are prepared with aluminum hydroxide, brucite, and DMMP. The effects of the hydroxides and DMMP on the foaming process and flame retarding properties of the foams are investigated by thermo gravimetric analysis, limiting oxygen index, and X‐ray powder diffraction. The thermal stability of the rigid polyurethane foams is close to that of the hydroxide fillers, with aluminum hydroxide providing better flammability performance than brucite. The hydroxide fillers and DMMP play a synergistic role in the rigid polyurethane foams and the limiting oxygen indices are up to 28.4% and 32.4%, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Christian Lenges Natnael Behabtu Jorge Mok Ibrahim Sendijarevic Aisa Sendijarevic 《应用聚合物科学杂志》2021,138(10):49979
Enzymatic polymerization is emerging as scalable method to convert sucrose to engineered polysaccharides. Polymer architecture and material properties can be controlled selectively to produce novel differentiated biomaterials. One first example for such an engineered polysaccharide is alpha-1,3-polyglucose (alpha-1,3-glucan) synthesized using glucosyltransferase (GTF) enzymes. Stable dispersions of alpha-1,3-glucan in polyether polyols were prepared with narrow particle size distributions, which are reactive with isocyanate allowing for covalent bonding to the hard segment of the polyurethane polymer matrix. This study further explored the use of alpha-1,3-glucan (PS) in the preparation of viscoelastics (VE) polyurethane foams. The introduction of alpha-1,3-glucan into the polyurethane polymer matrix was found to increase the load-bearing properties of VE foams without impacting the density. Other key performance properties of VE foams were effectively unchanged, including resilience, tensile, and tear strength. Cell size and morphology were also unaffected. The glass transition of these VE foams was not impacted; however, the overall thermal dimensional stability was improved as considerable reduction in compression set was observed. The results of this study indicated that alpha-1,3-glucan disperses in polyether polyols to improve performance characteristics of the VE foams, as well as other flexible polyurethane foams properties. 相似文献
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飞机座椅垫用聚氨酯软质泡沫发展现状及适航标准 总被引:1,自引:0,他引:1
简述了飞机座椅用聚氨酯软质泡沫的发展现状及阻燃聚氨酯软泡的研究进展,展望了用于飞机座椅的聚氨酯材料的市场和前景。详细介绍了美国联邦航空局(FAA)及空中客车公司适用于飞机座椅垫的适航标准。 相似文献
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Thermogravimetric and qualitative analysis of thermal decomposition characteristics of polyurethane foams based on polyols with carbamide or oxamide and borate groups
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The thermal stability and the kinds of products of thermal decomposition of polyurethane foams modified with urea or oxamide and borate groups were studied. Incorporation of urea or oxamide groups and borate groups enhances the thermal stability of polyurethane foams compared to polyurethane foams based on typical polyols. Thermal stability of foams modified with oxamide groups is somewhat higher that of foams modified with urea groups. In turn, simultaneous incorporation of borate groups results in an increase in thermal stability of the foams modified with urea. The temperature of thermal decomposition of the foams with oxamide and borate groups does not change or undergoes a slight decrease. The thermal degradation products of investigated foams are similar and they are usually water, ammonia, carbon dioxide and/or nitrous oxide. Additionally, hydrogen cyanide can be released during thermal decomposition of polyurethane foams modified with urea groups. The presence of borate groups prevents the formation of hydrogen cyanide. The opposite situation is observed in the case of the foams modified with oxamide and borate groups. Thus, from the point of view of a fire hazard, the use of the foams modified with urea and borate groups is safer. © 2017 Society of Chemical Industry 相似文献
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Polyurethane foams were prepared from the liquefied cornstalk polyol, which was obtained by the liquefaction of cornstalk in the presence of polyhydric alcohols using sulfuric acid as catalyst. The advisable liquefaction reaction conditions were selected by investigating their influences on the properties of liquefied cornstalk polyol, taking account of the requirement for the preparation of appropriate polyurethane foams. The influences of the contents of catalysts, water, surfactant, and isocyanate on the properties of polyurethane foams were also discussed, and feasible formulations for preparing cornstalk‐based polyurethane foams were proposed. The results indicated that the foams prepared from such liquefied cornstalk polyol exhibited excellent mechanical properties and thermal properties, and could be used as heat‐insulating materials. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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通过界面聚合法合成了一种线性富磷化阻燃剂(LPRFR),将LPRFR与可膨胀石墨(EG)复配制备了阻燃聚氨酯泡沫(RPUF),使用红外光谱分析仪、核磁共振分析仪对阻燃剂LPRFR的化学结构进行了表征,并通过极限氧指数仪、锥形量热仪、扫描电子显微镜和红外光谱分析仪对RPUF的燃烧性能、微观形貌和化学结构进行了分析。结果表明,仅10%(质量分数,下同)的LPRFR与8%EG复配后,RPUF的极限氧指数(LOI)便达到26.1%;LPRFR和EG能大幅降低RPUF的热释放速率,并提高基体的成炭能力;LPRFR参与了燃烧过程中的成炭反应,形成了含P—O—C及P=O结构的高质量炭层,有效隔绝了氧气和热量;LPRFR是一种对于聚氨酯泡沫阻燃性能优异的新型阻燃剂。 相似文献