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E-51环氧树脂改性双酚A型氰酸酯树脂的研究 总被引:3,自引:0,他引:3
采用示差扫描量热法(DSC)、傅里叶变换红外光谱(FTIR)研究了E-51环氧树脂改性双酚A型氰酸酯树脂(BADCy)体系的反应活性、反应机理及固化工艺,通过TGA分析了不同含量E-51环氧树脂改性BADCy后固化物的热性能,并测定了体系的吸水率及力学性能。结果表明,随着E-51环氧树脂用量的增加,BADCy改性体系的反应活性逐渐提高,固化温度逐渐降低;用环氧树脂改性BADCy生成了恶唑烷酮等芳杂环结构,降低了氰酸酯树脂体系的三嗪环交联密度,增加了体系的韧性;改性后材料的起始热分解温度均在380℃以上,吸水率均低于2%。 相似文献
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环氧树脂含量对氰酸酯热学性能的影响研究 总被引:1,自引:0,他引:1
采用示差扫描量热法(DSC)和热失重分析法(TGA)研究了环氧树脂含量对氰酸酯树脂固化反应特性、热稳定性以及热膨胀系数的影响。结果表明,环氧树脂的加入可有效降低改性体系的固化反应活化能,同时体系的热稳定性和尺寸稳定性有不同程度的削弱。当环氧树脂质量分数达到20%时,改性体系的表观活化能为65.4 kJ/mol,耐热温度指数为174℃,较纯氰酸酯树脂分别降低了25.8%和21.4%。当环氧树脂质量分数达到50%时,改性体系的热膨胀系数为65.3 922×10-6/℃(25~150℃),较纯氰酸酯树脂提高了8.13%。 相似文献
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合成了不同层数的端羧基超支化聚合物(HBPs-COOH),其与2-甲基咪唑(2-MI),苯甲醇(BP)分别进行酰胺化反应和酯化反应得到了超支化咪唑酰胺化衍生物(HBPIAD)并将其用作环氧树脂中温固化剂。通过红外(FTIR)、动态力学热分析(DMA)、热重分析(TGA)、扫描电镜(SEM)、力学性能测试等方法对固化剂结构及环氧树脂固化物的性能进行了研究。结果表明,超支化咪唑酰胺化衍生物降低了咪唑的固化反应活性,提高了其与环氧树脂的相容性,HBPIAD-1改性后的环氧树脂固化物的力学性能有所提高,拉伸强度可达40.44 MPa,弯曲强度91.44 MPa,冲击强度12.13 kJ/m2,但是随着超支化层数的增加,环氧树脂固化物的力学性能和耐热性有所下降。 相似文献
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通过有核一步法,合成了端羧基超支化聚酯(CHP),然后与环氧氯丙烷经环氧化反应制备了端环氧基超支化聚酯(EHP),并制备了EHP改性环氧树脂(EP)体系。利用傅立叶变换红外光谱法、核磁共振氢谱法、凝胶渗透色谱法、差示扫描量热法、热变形温度分析、热失重分析、扫描电子显微镜等对EHP结构、改性EP体系固化工艺、力学性能、热性能等进行了研究。结果表明,合成了预期结构的EHP,数均分子量为1 908 g/mol,黏度为1 522.5 m Pa·s;当EHP含量为15 g时,改性EP体系的性能最佳,其冲击强度和弯曲强度分别为50.4 k J/m2,201.0 MPa,较改性前分别提高了213%,37%;热变形温度为147.5℃,热失重10%时的温度为360℃,较改性前分别下降了9%,7.7%。 相似文献
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以丙烯酸正丁酯(BA)、甲基丙烯酸甲酯(MMA)及甲基丙烯酸缩水甘油酯(GMA)为单体通过悬浮聚合反应合成了共聚物P(MMA-BA-GMA)简称(PMBG),采用傅里叶红外光谱仪、核磁共振波谱仪、凝胶渗透色谱仪对PMBG的结构与组成进行了表征。采用合成的PMBG对环氧树脂(DER663)/固化剂(HTP-305)体系进行增韧改性,研究了PMBG含量对体系力学性能和热性能的影响,并通过扫描电镜(SEM)对固化物断面的微观结构进行了分析。结果表明:PMBG改性后的环氧树脂冲击强度及断裂伸长率提高,当PMBG的质量分数为5%时,冲击强度显著提高,增韧改性效果最好,并且对体系的玻璃化转变温度(Tg)影响不大;共聚物在体系固化时发生微相分离,因而提高了环氧树脂的韧性。 相似文献
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研究了二烯丙基双酚A(DBA)催化改性酚醛型氰酸酯树脂(cy-5),通过差示扫描量热法(DSC)、热重分析(TG)、冲击性能和动态热机械分析(DMA)测试,分析了改性树脂的热性能和力学性能。研究表明:DBA对cy-5有催化和增韧的双重作用,当DBA的添加量为5%(质量分数)时,催化效果最为明显,含10% DBA的改性树脂固化物的冲击强度达到7.41 kJ/m2,改性树脂固化物的玻璃化转变温度(Tg)和储能模量(E')均有所降低,但幅度不大。 相似文献
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苯并噁嗪(BZ)和双马来酰亚胺(BMI)按照不同的配比进行共混固化。用FTIR、DSC、凝胶化时间、DMA、TGA、万能电子拉力机分别研究了BZ/BMI共混体系的固化行为以及BZ/BMI固化树脂的热性能和剪切强度等。结果表明BZ和BMI除了发生均聚反应,还发生苯并噁嗪开环生成的酚羟基和双马来酰亚胺的双键生成醚键的反应。BZ和BMI共混后,固化温度比各自的固化温度都低。BMI的加入提高了共混树脂的热性能,BZ/BMI固化树脂的Tg达289℃,Td5达387℃,Td10达422℃,800℃的残炭率达55.3%。另外,BMI的加入提高了BZ/BMI固化树脂的剪切强度,当BMI的含量为60%时,BZ/BMI固化树脂的剪切强度为12.44 MPa。进一步,制备了玻璃布增强的BZ/BMI层压板,并对其力学性能和断面形貌进行了研究。结果表明,当BMI用量为40%时,BZ/BMI层压板的拉伸强度、弯曲强度、冲击强度分别达394 MPa、490 MPa、160 kJ·m-2。 相似文献
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Epoxidized soybean oil (ESO) was thermally cured using methylhexahydrophthalic anhydride (MHHPA) curing agent in the presence
of 2-ethyl-4-methylimidazole (EMI) catalyst. The curing characteristics of ESO/MHHPA/EMI systems were characterized using
Fourier transform infrared spectroscopy (FTIR), a dynamic mechanical analyzer (DMA) and a differential scanning calorimeter
(DSC). FTIR spectra showed that the polyesterification rate in ESO/MHHPA/EMI systems increased with increasing of the catalyst
concentration. DSC thermograms indicated that EMI-catalyzed ESO/MHHPA systems experienced enthalpy relaxation at low EMI concentration
whereas the extent decreased with increasing of the EMI concentration. There is a direct relationship between the degree of
conversion and crosslink density of the thermal cured ESO/MHHPA/EMI systems with EMI concentration. The curing characteristics
of thermal curable ESO thermosetting resins were found to have influence on the thermal properties of the ESO systems. It
was determined that the glass transition temperature (T
g) and storage modulus (E′) of cured ESO increased with increasing the EMI concentration whereas the damping properties of the ESO/MHHPA/EMI systems
exhibited the reverse trend. It was found that the thermally curable ESO thermosetting resins experienced a two-stage thermal
decomposition process. 相似文献
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A series of bismaleimide resins based on phthalide‐containing monomer have been prepared by the copolymerization reaction of 3,3‐bis[4‐(4‐maleimidophenoxy)phenyl] ‐phthalide (PPBMI), 4, 4'‐dimaleimido diphenylmethane (MBMI) and 2, 2'‐diallyl bisphenol A (DABPA) in different feed ratios. The curing behavior, thermal, mechanical and physical properties and compatibility of all resultant resins were carefully characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), notched Izod impact test, water absorption test and scanning electron microscopy (SEM). DSC investigations showed that with an increase of the weight ratio of PPBMI, the dominating exothermic polymerization temperature (Tp) increased. The glass transitions were observed from DMA thermograms for the cured BMI resins in the temperature range from 277°C to 311°C and decreased with increasing PPBMI content. The TGA results indicated the thermal stability was improved as PPBMI content increased. The investigations of the mechanical properties showed a complicated trend with an increase in PPBMI content. In addition, the equilibrium water uptake of the modified resins was reduced as PPBMI content increased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1084‐1091, 2013 相似文献
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超支化聚合物改性环氧树脂固化体系力学性能研究 总被引:1,自引:0,他引:1
研究了羟端基脂肪族超支化聚酯(HBPE)对环氧树脂(EP)固化体系力学性能的影响。结果表明,加入较低含量的HBPE就能较好地改善体系的拉伸强度和冲击强度,同时对拉伸弹性模量的影响不大。其中,第三代和第四代HBPE的质量分数为3%时,固化体系的拉伸强度分别提高20.54%和18.64%,断裂伸长率分别提高41.02%和58.66%,冲击强度分别提高71.14%和117.36%。对固化体系的拉伸断面进行了分析,发现引入HBPE后,材料表现出韧性断裂;HBPE以微分散相的形式均匀分散在EP基体中。 相似文献
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《国际聚合物材料杂志》2012,61(7):520-531
A new curing agent based on palmitoleic acid methyl ester modified amine (PAMEA) for epoxy resin was synthesized and characterized. Diglycidyl ether of bisphenol A (DGEBA) epoxy resins cured with different content of PAMEA along with diethylenetriamine (DETA) were prepared. The mechanical properties, dynamic mechanical properties, thermal properties, and morphology were investigated. The results indicated that the PAMEA curing agent can improve the impact strength of the cured epoxy resins considerably in comparison with the DETA curing agent, while the modulus and strength of the cured resin can also be improved slightly. When the PAMEA/epoxy resin weight ratio is 30/100, the comprehensive mechanical properties of the cured epoxy resin are optimal; at the same time, the crosslinking density and glass transition temperature of the cured epoxy resin are maximal. 相似文献