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1.
Palm oil‐based polyester polyol is synthesized by ring opening reaction on epoxidized palm olein by phthalic acid. The reaction is carried out in a solvent free and noncatalyzed condition with the optimal reaction condition at 175°C for 5 h reaction time. The physical state of the product is a clear bright yellowish liquid with low viscosity value of 5700–6700 cP at 25°C and pour point of 15°C. The chemical structure and molecular weight of the polyester polyol were characterized by FTIR, 1H‐NMR, 13C‐NMR, and GPC. The optimal polyol with molecular weight of 36,308 dalton and hydroxyl value of 78.17 mg KOH/g sample was reacted with polymeric 4,4′‐methylene diphenyl diisocyanate (pMDI) at isocyanate index of 1.3 to produce polyurethane adhesive. The lap shear strength of the polyurethane adhesive showed two times higher than the commercial wood adhesives. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39967.  相似文献   

2.
采用可再生的醇解蓖麻油多元醇为原料,与液溴进行加成反应制备溴化蓖麻油多元醇,通过红外光谱证实发生了溴化反应,并测定了产物粘度、羟值、酸值.通过发泡实验和氧指数、烟密度、水平燃烧等测试手段,考察了溴化蓖麻油基聚氨酯硬泡发泡参数和阻燃性质,并与工业级阻燃荆雅保RB-79制备的聚氨酯硬泡进行比较.结果表明,由溴化蓖麻油多元醇...  相似文献   

3.
Oleic acid is a typical unsaturated fatty acid that is found widely in vegetable oils. The objective of this investigation was to produce a new type of oleic‐based polyol from oleic acid. Possible advantages of this approach include the production of high‐performance polyurethane materials from renewable resources and value‐added research for oleic acid. Oleic‐based polyols were synthesized by a three‐step process consisting of epoxidation and ring‐opening reaction, followed by esterification. The synthesized polyols appeared as a viscous liquid at room temperature with hydroxyl numbers from 307 to 425 mg KOH/g. Preparation of polyurethane foams using oleic‐based polyols and isocyanate was studied. An environmentally friendly blowing agent, HCFC‐141b, together with a small amount of water, was used. The synthesized foams were characterized by FTIR, SEM, and TG/DSC. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

4.
Telechelic oligoisoprenes were successfully prepared by the selective controlled degradation of natural rubber, a renewable source, via epoxidation and cleavage reactions. The molar mass of the oligoisoprene product obtained depends on the degree of epoxidation of the starting materials. The chemically modified structures obtained via epoxidation, hydrogenation, and ring opening of epoxide groups were also studied, and the chemical structures and thermal properties of the oligoisoprene products were determined. Moreover, the preliminary study of preparation of hydroxytelechelic natural rubber (HTNR)‐based polyurethane foam was performed. A novel HTNR‐based polyurethane foam was successfully prepared and its thermal properties were investigated and the results indicated that the HTNR‐based polyurethane foam has a good low temperature flexibility. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

5.
利用甲基磷酸二甲酯(DMMP)与多元醇经酯交换反应制备了反应型含磷阻燃多元醇,研究了催化剂种类和用量及反应温度、时间等工艺参数对酯化反应转化率的影响,同时优化了工艺条件,合成的多元醇含磷量可达12%~15%。将合成的多元醇替代部分聚醚4110用于制备阻燃聚氨酯硬泡,采用极限氧指数法(LOI)对其阻燃性能进行了表征,并与普通聚氨酯硬泡进行了比较。研究结果表明,在添加少量的混合阻燃剂时,阻燃聚氨酯硬泡的LOI可达30%以上。  相似文献   

6.
无CFC硬泡用低粘度聚醚多元醇   总被引:4,自引:0,他引:4  
介绍了一种具有自乳化性、高羟值低粘度聚醚多元醇。以该聚醚多元醇为基础,制备了无CFC或CFC减半PU硬泡,包括HCFC-141b减关体系、正(异)戊烷发泡体系、全水发泡及CFC-11减半体系。实验结果表明,该聚醚与HCFC-141b、戊烷及水等相溶性好,组合料贮存稳定,硬泡物性优良,说明该聚醚可广泛应用于各种无CFC PU硬泡体系。  相似文献   

7.
A new type of rigid polyurethane foam was produced by incorporating oxazolidone heterocyclic rings on to polyurethane backbones. Epoxidized diethanolamides were synthesized by reacting palm oil blends of epoxidized palm olein and refined bleached deodorized palm kernel olein with diethanolamine to produce rigid polyurethane foams. Epoxides, retained in the diethanolamides, reacted with isocyanate during foam production in the presence of AlCl3–THF complex catalyst to form oxazolidone linkages in the polyurethane network. The carbonyl stretch of oxazolidone was identified at 1,750 cm−1 through Fourier Transform Infra Red analysis. Chemical modifications of the polyurethane network also improved the thermal and mechanical properties of the foams. In addition, isocyanate index 1.4 was determined to be the most suitable in the production of foams from this newly synthesized epoxidized diethanolamides.  相似文献   

8.
用聚醚多元醇A、聚醚二醇B、聚酯多元醇PS-2915、三乙醇胺、水和其他助剂制备了喷涂管道用全水发泡聚氨酯硬泡组合聚醚,并对其反应性能、黏度进行评价,对使用该组合聚醚和多异氰酸酯PM-200制得的聚氨酯泡沫材料的性能进行研究。结果表明,在合适的原料用量时,制得的组合聚醚黏度较低,与多异氰酸酯PM-200的反应速度满足喷涂管道生产工艺要求。当喷涂制得的聚氨酯泡沫单层厚度7 mm左右,泡沫体具有较高的粘接强度、较好的韧性和较低的导热系数,密度61 kg/m^3的泡沫压缩强度达到526 kPa。制得的喷涂管道产品满足GB/T 34611—2017要求。  相似文献   

9.
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   

10.
Novel flexible polyurethane foams were successfully prepared from a renewable source, hydroxytelechelic natural rubber (HTNR) having different molecular weights (1000–3400 g mol?1) and variation of epoxide contents (EHTNR, 0–35% epoxidation) by a one‐shot technique. The chemical and cell structures as well as physico‐mechanical, thermal, and acoustic properties were characterized and compared with commercial polyol analogs. The obtained HTNR based foams are open cell structures with cell dimensions between 0.38 and 0.47 mm. The HTNR1000 based foam exhibits better mechanical properties but lower elongation at break than those of commercial polyol analog. However, the HTNR3400 based foam shows the best elastic properties. In a series of EHTNR based foams, the tensile and compressive strengths show a tendency to increase with increasing epoxide content and amount of 1,4‐butanediol (BD). The HTNR based foams demonstrate better low temperature flexibility than that of the foam based on commercial polyol. Moreover, the HTNR based polyurethane foams was found to be an excellent absorber of acoustics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

11.
The composition of crude algal oil was analyzed and determined by several methods. Oil was converted to polyols by ozonolysis, epoxidation, and hydroformylation. Ozonolysis gave a polyol with lighter color but a low OH number and was unsuitable for polyurethane applications. Epoxidation also improved the color and gave a polyol with an OH number around 150 mg KOH/g, which with diphenylmethane diisocyanate gave a homogeneous, rubbery, transparent sheet. Desirable rigid foams were prepared with the addition of water to the formulation. Hydroformylation was carried out successfully giving an OH number of about 150 mg KOH/g, but the polyol was black. Casting the polyurethane sheet was difficult due to the very high reactivity of the polyol. Polyurethane foam of lower quality than from epoxidation polyol was obtained. More work on optimization of the foaming system would improve the foam. Crude algal oil is a viable starting material for the production of polyols. Better results would be obtained from refined algal oils.  相似文献   

12.
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   

13.
综述了大豆油基聚氨酯的制备方法及应用,以大豆油为绿色原料,通过环氧化得到环氧大豆油,利用环氧大豆油开环制得大豆油基多元醇,再用此多元醇与异氰酸酯反应得到大豆油基聚氨酯泡沫、大豆油基聚氨酯乳液以及溶剂型大豆油基聚氨酯树脂。同时介绍了大豆油基聚氨酯在泡沫、涂料、胶粘剂等领域的具体应用。  相似文献   

14.
以大豆油与环氧化剂反应,生成环氧大豆油;在催化剂的存在下与含活泼氢的亲核试剂发生环氧键开环反应,生成混合羟基脂肪酸甘油酯;加入醇并升温进行醇解反应,生成混合羟基脂肪酸单酯,即大豆油基多元醇。将大豆油基多元醇与异氰酸酯(MDI)等反应即可制得硬质聚氨酯泡沫塑料,具体配方为100份大豆油基多元醇,80~150份MDI、0.3~4份三乙醇胺、0.5~4份匀泡剂、0.5~3份蒸馏水。  相似文献   

15.
A diol‐based refined, bleached, and deodorized (RBD) palm kernel oil polyol was prepared. It was found that the polyurethane foam produced only gives a good compressive strength property at a 45 kg/m3 molded density. The combination of sorbitol into the polyol system resulted in a better dimensional stability and improved thermal conductivity as well as enhanced compressive strength. These were obtained by increasing the functionality of the polyol (functionality of 4.5) through introduction of a high molecular weight and branching polyhidric compound. Direct polycondensation and transesterification methods were used for the syntheses. The hydroxyl value, TLC, and FTIR were used to study the completion of the reaction. A comparative study of the mechanical properties and morphological behavior was carried out with a diol‐based polyol. From the water‐blown molded foam (zero ODP) with a density of about 44.2 kg/m3 and a closed‐cell content of 93%, a compressive strength of 222 kPa and a dimensional stability of 0.09, 0.10, and 0.12% at the length, width, and thickness of the foam, respectively, conditioned at ?15°C for 24 h, were obtained. The thermal conductivity improved to an initial value of 0.00198 W/mK, tested at 0°C. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 384–389, 2001  相似文献   

16.
The study investigated an approach to incorporate modified epoxidized soy‐based vegetable oil polyol as a replacement for petroleum‐based polyether polyol and to substantially reduce the isocyanate loading in the rigid foam formulation. Noncatalytic polymerization of epoxidized bodied soybean oil and ethylene glycol (EG) was carried out in a closed batch reaction. Cleavage of the oxirane rings and hydroxyl group attachment at optimum conditions provided the desired polyol products. The polyols were characterized based on its hydroxyl numbers, acidity, viscosity, iodine number, and Gardner color index for quality purposes. Reactions of oxirane ring and EG were verified by spectroscopic FTIR. Crosslinking performance was evaluated by extractability analysis on the polyurethane (PU) elastomer wafers. Rigid foaming performed at 50 and 75% petroleum‐based polyether polyol replacements have shown excellent thermoinsulating and mechanical properties compared with epoxidized soybean oil (ESBO) alone or petroleum‐based polyether polyol alone. A reduction of up to 8% of the polymeric diphenylmethane diisocyanate was achieved using the synthesized ESBO‐EG‐based polyols. A higher average functionality polyol is key component to the reduction of isocyanate in PU synthesis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

17.
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   

18.
The product of 1‐butene metathesis of canola triacylglycerol (CMTAG), with shortened structures, terminal double bonds (50% of the total), and oligomers (40% dimer and trimer, and 10% higher oligomers) was used to synthesize novel polyols and polyurethane foams. A non‐chlorinated (Pol‐1) and a chlorinated polyol (Pol‐2) having OH value (170 and 190 mg KOH/g, respectively) were synthesized from CMTAG by epoxidation followed by hydroxylation, and epoxidation followed by hydrogenation, respectively. Both polyols remained liquid below ambient temperature and demonstrated physical characteristics such as viscosity which allowed for the facile preparation of polyurethane foams. The foam obtained with Pol‐1 was relatively soft (~0.32 MPa at 10% strain) and very flexible (recovery ~90%); whereas, the foam obtained with Pol‐2 was semi‐rigid (~1.1 MPa at 10% strain and recovery of 64%). The higher strength and rigidity of Pol‐2 foam compared to Pol‐1 foam is chiefly attributable to the effect of the bulky chlorines on the crosslink density. Importantly, this work highlights that one can improve and control jointly the mechanical properties and deformation recovery ability of bio‐based foams by combining primary functional groups, oligomers, and high molar volume molecules in the polyols. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46616.  相似文献   

19.
Castor oil polyol (COP) having a hydroxyl number of 400?mg?KOH/g was prepared through the transesterification reaction of castor oil with glycerol. The effect of reaction temperature on the composition, hydroxyl number and viscosity of the COP products was studied. A series of rigid polyurethane foams were synthesised using the mixtures comprising COP and a petroleum-based polyol with various proportions as polyol component. It was found that the foaming rate, compressive strength and dimensional stability and morphology of resulting foams were dominated by the foam formulation, in a more accurate way, COP content in the polyol mixtures. The combination of expandable graphite and dimethyl methyl phosphonate exhibited stronger flame retardant function which was ascribed to the synergistic effect associated with the simultaneous presence of the two additives. An improvement in thermal stability was observed due to the inclusion of the flame retardants.  相似文献   

20.
合成了聚氨酯改性聚醚多元醇(PIPA多元醇),采用傅里叶变换红外光谱法、凝胶渗透色谱法等方法对其进行表征,发现聚醚多元醇A(TMN-450)/三乙醇胺/甲苯二异氰酸酯为110/10/9(质量比,下同)时,所合成的PIPA多元醇固含量为15 %左右,黏度约为3 400 mPaos,其作为发泡原料性能较好。采用此多元醇制备硬质聚氨酯泡沫塑料,考察泡沫稳定剂对体系发泡时间、泡沫塑料的泡孔结构、压缩强度、弯曲强度、冲击强度等力学性能的影响,发现加入1.0份泡沫稳定剂的样品泡孔平均直径约为0.5 mm,孔径分布窄,约40 s起泡,与未改性多元醇制备的泡沫塑料相比,冲击强度提高了23 %,压缩强度和弯曲强度略有上升,同时提高了泡沫塑料的强度和韧性。  相似文献   

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