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《热固性树脂》2010,(5)
通过分子结构设计先合成了低平均聚合度端羟基不饱和聚酯(UP),再与异氰酸酯(PU)共聚反应,得到了一种异氰酸酯嵌段改性不饱和聚酯树脂。通过力学性能测试和红外光谱分析研究了UP/PU共聚体各合成反应阶段分子官能团的变化,醇酸比、二元醇种类对UP齐聚物的平均聚合度和粘度的影响,UP/PU共聚体中PU链段对固化后树脂力学性能的影响以及其玻纤复合材料的性能。结果表明,UP/PU浇铸体及玻纤复合材的拉伸强度分别为75MPa,956MPa,弯曲强度分别为116MPa,1220MPa,UP/PU共聚改善了现有不饱和聚酯树脂脆性大、固化收缩率高及与玻璃纤维的粘结性差等缺点。 相似文献
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以邻苯型不饱和聚酯(UP)树脂为基体、以苎麻布为增强材料,在室温条件下模压成型制备苎麻布/UP树脂复合材料,利用同时热分析仪STA研究了该复合材料的耐热性能,并将其力学性能与纯UP树脂浇铸体的相应性能进行了对比研究。结果表明:苎麻/UP树脂复合材料的耐热性能较纯UP树脂浇铸体有所提高;其拉伸强度及拉伸模量、弯曲强度及弯曲模量、冲击强度等各项力学性能指标均明显优于纯UP树脂浇铸体。 相似文献
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利用与天然纤维具有良好亲和性的聚酯聚氨酯(PU)改性不饱和聚酯(UP),通过扫描电镜(SEM)、傅里叶红外光谱(FT-IR)、接触角和力学性能等,研究了改性不饱和聚酯的微观结构、反应程度和主要性能.研究结果表明,引入PU提高了不饱和聚酯树脂的韧性,增加了与天然纤维的界面浸润性,降低了不饱和聚酯树脂的固化收缩率.所得改性不饱和聚酯的冲击断裂截面表现为韧性断裂;与天然纤维的接触角随着聚氨酯添加量的增加而降低,表明改性不饱和聚酯与天然纤维的浸润性增强.力学性能测试表明,当PU含量为5%时,其冲击强度可提高80%,弯曲模量降低小于20%,固化收缩率低于4%. 相似文献
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用正交实验法优化工艺条件,以二氨基二苯醚(ODA)与顺丁烯二酸酐(MA)反应合成了二苯醚双马来酰亚胺,产品收率达94.51%,纯度为99.40%。通过DSC、TG分析和拉伸性能测试比较了四种由二苯醚双马来酰亚胺,二苯甲烷双马来酰亚胺分别与二元胺,二烯丙基双酚A,环氧树脂共聚得到的产物的耐热性及力学性能。二苯醚双马来酰亚胺与二元胺及二烯丙基双酚A的共聚物的初始热失重温度,失重60%的温度,650℃时残炭率及其与环氧树脂共聚物的拉伸强度均优于二苯甲烷双马来酰亚胺体系。结果表明,二苯醚双马来酰亚胺的综合性能优于二苯甲烷双马来酰亚胺。 相似文献
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《现代化工》2017,(6)
采用原位聚合法制备了以三聚氰胺-脲甲醛为壁材,环氧E-51为芯材的微胶囊(MUF),并将其应用到碳纤维(CF)增强不饱和聚酯(UP)复合材料中,详细探讨了CF质量分数和MUF质量分数对碳纤维/不饱和聚酯(CF/UP)复合材料和微胶囊/碳纤维/不饱和聚酯(MUF/CF/UP)复合材料热稳定性、力学性能和自修复性能的影响。通过OM和SEM观察MUF的表面形貌,FTIR对MUF、CF/UP复合材料和MUF/CF/UP复合材料的化学结构进行表征,TGA、悬臂梁冲击仪和万能拉力试验机对复合材料的热稳定性、冲击性能、拉伸性能和自修复性能进行测试。结果表明,CF和MUF质量分数均为1%时,MUF/CF/UP复合材料的热稳定性较佳,力学性能及自修复性能较优;其拉伸强度为3.99 MPa,弹性模量为229.58 MPa,断裂伸长率为2.12%,冲击强度为86.75 k J/m~2,自修复效率为62.02%。 相似文献
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不饱和聚酯(UP)是一种重要的热固性树脂,用纤维增强的不饱和聚酯具有极广泛的应用。随着对不饱和聚酯应用要求的提高,纤维增强UP技术有了进一步的发展。影响纤维增强UP复合材料性能的因素很多,本题结合有关影响因素,介绍近几年来纤维增强UP复合材料的研究进展。 相似文献
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采用KH570对介孔二氧化硅SBA-15进行表面处理,通过原位聚合方法合成SBA-15/不饱和聚酯(UP)复合树脂,后再通过共混、辊炼、模压成型制备了SBA-15/UP复合材料。研究了加入SBA-15对SBA-15/UP复合材料的摩擦磨损性能、硬度、动态力学性能的影响,通过扫描电子显微镜(SEM)对复合材料的磨损表面形貌进行观察。结果表明,经改性后的SBA-15加入使复合材料的体积磨损率降低了26%,玻璃化温度提高了16℃。 相似文献
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An unsaturated polyester (UP) resin was modified by the addition of a thermosetting bismaleimide (BMD) as a second coreactive monomer. The copolymers were characterized in terms of mechanical, thermal, and morphological properties by tensile, bend, and impact testing; thermogravimetric analysis; heat deforming temperature analysis; dynamic mechanical analysis; and scanning electron microscopy. In addition, Fourier transform infrared spectroscopy of modified resin indicated that crosslinking networks were formed between BMD and UP. The properties of the modified resins were compared with those of unmodified resins. The results indicate that the addition of BMD not only improved the thermal decomposition temperature and heat deforming temperature but also caused small changes in the mechanical properties. The effect of the construct of BMD and the reactions among BMD, UP, and styrene were analyzed. The results show that BMD has great potential to improve the properties of UP. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 593–598, 2006 相似文献
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通过在不饱和聚酯树脂中加入活性端基聚氨酯橡胶来降低树脂的体积收缩.树脂固化前,橡胶与不饱和聚酯树脂相溶性好;树脂固化时橡胶中的不饱和双键反应可参与反应,并呈一定粒径的胶粒析出.本文研究了几种活性端基聚氨酯橡胶对不饱和聚酯树脂收缩控制的影响. 相似文献
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活性端基聚氨酯橡胶改性不饱和聚酯树脂的研究(Ⅰ) 总被引:3,自引:0,他引:3
通过在不饱和聚酯树脂中加入活性端基聚氨酯橡胶对树脂进行增韧.树脂固化前,橡胶与不饱和聚酯树脂相溶性好;树脂固化时,橡胶中的不饱和双键可参与反应,并与树脂发生相分离.改性后,树脂的冲击强度可提高60%以上,而且拉伸强度、弯曲强度及马丁耐热温度等物理机械性能的保持率也达60%以上. 相似文献
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Kyung‐Eun Min Yeong‐Geun Hwang Gwan‐Young Choi Ho‐Gyum Kim Woo‐Sik Kim Dong‐Ho Lee Lee‐Soon Park Kwan‐Ho Seo Inn‐Kyu Kang Il‐Ryun Jun Jeong‐Cheol Lim Han‐Chul Song 《应用聚合物科学杂志》2002,84(4):735-740
Unsaturated polyester (UP) resin is one of the major thermosetting resins and is very useful as a matrix resin of composite material for its processibility. UP resin, however, has several shortcomings: it is weak in alkalis, volume shrinkage occurs during the crosslinking reaction of the oligomeric UP resin with a styrene monomer, and it is also brittle. The mechanical properties of UP resin can be enhanced by blending it with various materials. In this study, polyurethane (PU) was used as a modifier to improve the toughness of the UP resin. The effect of the polyol molecular weight as a PU soft segment and the PU contents on the toughness of PU‐modified UP resins were studied. A UP/PU polymer network may occur through a reaction between an isocyanate group in the methyl diisocyanate (MDI) and a hydroxyl one in the UP molecules. The maximum toughness was observed at approximately 2 wt % of the PU content. These results can be rationalized by the incorporation of a rubbery PU segment into a brittle UP resin. © 2002 John Wiley & Sons, Inc. J Appl Polym Sci 84: 735–740, 2002; DOI 10.1002/app.10169 相似文献
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In this study, unsaturated polyester (UP) resin was reinforced by using an organically-modified montmorillonite (OMMT) and toughened with poly(n-butyl acrylate)/poly(vinyl acetate-co-methyl methacrylate) core-shell rubber (CSR) particles. The effects of OMMT and CSR levels on the fracture behavior and tensile properties of UP were investigated. The results showed that the incorporation of OMMT of up to 3?wt.% increased the UP fracture toughness (KIC) to some extent, while further addition caused the fracture toughness to reach a constant level. Furthermore, the dispersion state of OMMT platelets and CSR particles inside the UP matrix was studied by means of transmission electron microscopy (TEM). TEM micrographs showed a good dispersion of organoclay tactoids with an intercalated structure or partial exfoliation for the UP reinforced by 1 and 3?wt.% OMMT. On the other hand, addition of 5 and 10?wt.% CSR particles to the UP increased the fracture toughness much more than the OMMT. Locally clustered but globally good CSR particle dispersion inside the UP matrix was observed in toughened UP specimens. Interestingly, a synergistic effect in fracture toughness was only observed for the UP hybrid composite containing 1?wt.% OMMT and 10?wt.% CSR particles, when compared with other reinforced, toughened, and hybrid specimens. In this case, the OMMT platelets were found to act as bridges between the small rubber-particle agglomerates, which may cause alternating clay debonding/CSR particle cavitation and improve plastic deformation inside the UP matrix. The incorporation of OMMT increased Young??s modulus and also decreased the tensile strength of the neat and CSR-toughened UP specimens with increasing the amount of OMMT. 相似文献
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Bingwen Long Keke Yao Shijie Zhu ZuHong Li Tong Li Fuli Deng Hua Deng Yigang Ding 《American Institute of Chemical Engineers》2023,69(1):e17894
A thermodynamic and kinetic study of the dissolution properties of urea phosphate (UP) in water is performed using a Calvet type microcalorimeter. Calorimetric measurements reveal the dissolution is endothermic and the heat is perfectly proportional to the amount of UP dissolved, yielding an enthalpy of (33.755 ± 0.65) kJ/mol. By combining the enthalpy data of our measurements and literature, we derive the enthalpies of urea-phosphoric acid adduct reaction, formation of solid UP and UP dissociation. Dissolution kinetics parameters are estimated using the collected dynamic calorimetric data that are well represented with quasi-second-order kinetic model, giving an activation energy of (16.7 ± 2.7) kJ/mol. Thermodynamic modeling of the pH difference between UP and phosphoric acid solutions shows the degree of UP dissociation decreases from 74% to 42% when UP molality increases from 0.02 to 1 mol/kg. Furthermore, the species molality distributions in UP solutions are calculated based on mass balance and the dissociation equilibrium relations considered. 相似文献
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In this study, unsaturated polyester resin (UP) is blended with resole type phenolic resin, co-crosslinking process performed and the resin blends show miscibility and interpenetration network (IPN) structure. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) are employed to examine the aggregate structure of crosslinked network of the UP/phenolic resin blend. Tensile fractured sections of the resin blends are observed using scanning electronic microscopy (SEM) to shed light on their miscibility. Tensile and flexural tests were also conducted to examine the mechanical properties of the UP/phenolic resin blends. The results show that UP20/Ph80 and UP40/Ph60 resin blends have well-formed Interpenetrating Network (IPN) structures while phase separation is observed for UP60/Ph40 resin blend. Finally, thermal cure of UP80/Ph20 resin blend is incomplete, thus showing immiscibility. The mechanical properties of all resin blends at different mixing proportions deviate from a linear relationship and show a concave curve, indicating the non-additive effect of blending. 相似文献
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Two polymerizable cationic surfactants, vinylbenzyl n‐alkyldimethyl (n = 12 or 18) ammonium chlorides, were used for functionalization of montmorillonite (MMT) and preparation of unsaturated polyester (UP)‐clay nanocomposites. Polymerizable organophilic clays were prepared by exchanging the sodium ions of MMT with vinylbenzyldodecyldimethyl ammonium chloride (VDAC) or vinylbenzyloctadecyldimethyl ammonium chloride (VOAC) in an aqueous medium. The dispersion of organoclays in UP led to gel formation. UP/VDAC‐MMT resulted in intercalated nanocomposites while UP/VOAC‐MMT formed partially exfoliated nanocomposites. The nanocomposites exhibited higher dynamic modulus than pristine UP. 相似文献