含三聚氰胺有机硅杂化物的环氧树脂性能研究

利用羟甲基化三聚氰胺和γ-环氧丙氧基三甲氧基硅烷反应制备了三聚氰胺有机硅杂化物,并用FTIR、29S iNMR对其结构进行了表征。然后将其与环氧树脂共混固化,对固化物热性能、阻燃性、力学性能进行了分析。结果表明,该三聚氰胺有机硅杂化环氧树脂固化物不仅保持纯环氧树脂玻璃化转变温度,而且在空气和氮气中的热失重分析显示,高温区域的热稳定性及残碳率比纯环氧树脂高;三聚氰胺有机硅杂化环氧树脂固化物的极限氧指数达到30.2,与纯环氧树脂相比,该固化物的极限氧指数提高了43%左右,抗冲击强度有较大幅度的提高,当三聚氰胺有机硅杂化物的添加量为环氧树脂质量的5%时,环氧树脂固化物的抗冲击强度达到20.3 kJ/mol;扫描电子显微镜照片显示三聚氰胺有机硅杂化环氧树脂的韧性较纯环氧树脂有很大提高。     

环氧树脂/含磷有机硅杂化物固化体系的耐热性与阻燃性研究

利用γ(2,3-环氧丙氧基)丙基三甲氧基硅烷与磷酸反应制备了一种含磷有机硅杂化物,并利用红外光谱对这种含磷有机硅杂化物进行了结构表征。将这种含磷有机硅杂化物加入到双酚A环氧树脂/4,4'-二氨基二苯基甲烷体系制备了环氧树脂/含磷有机硅杂化物固化体系,对这种固化物进行了热失重分析,并测试了其玻璃化转变温度(Tg)和极限氧指数。结果表明,该固化物的Tg比纯环氧树脂固化物有所提高,初始分解温度比纯环氧树脂低,而高温残炭率有大幅提高;当含磷有机硅杂化物含量为30份时,固化物的Tg提高9 ℃,极限氧指数到达27.3 %,700 ℃残炭率达到34.1 %,比纯环氧树脂分别提高28 %和77.8 %。     

阻燃型含硅环氧树脂体系的研究进展

把硅元素引入环氧树脂体系中,硅-磷、硅-氮等协同阻燃效应能使固化物得到优异的阻燃性能。概述了硅系阻燃剂的阻燃机理,介绍了阻燃型含硅环氧树脂体系和含硅固化剂体系的阻燃效果以及硅和磷、氮等元素的协同阻燃效应。     

硅、磷阻燃型环氧树脂的现状与研究

由于含硅、磷物质本身的阻燃性能优越,用含硅、磷物质改性环氧树脂成为提高其阻燃性的重要方法。本文主要介绍了含硅、磷阻燃型环氧树脂的发展状况与研究进展。     

磷杂菲化合物的合成与阻燃EP/PET 复合材料的性能研究

合成了一种磷杂菲化合物(POH),并将其添加到双酚A二缩水甘油醚型环氧树脂(DGEBA)/4,4’一二氨基二苯砜(DDS)与聚对苯二甲酸乙二醇酯(PET)的复合体系中,制备了一系列复合材料POH/PET/DGEBA/DDS。通过极限氧指数(LOI)测试、垂直燃烧(UL-94)测试、热重分析(TGA)和三点弯曲测试了POH/PET/DGEBA/DDS的阻燃性能、热稳定性能和机械性能。实验结果表明：当体系含磷量达1.5wt%时,POH-1.5/PET/DGEBA/DDS在700℃的残炭生成量高达43.9%,LOI值达32.5%,并达UL-94 V-0级,呈现了优异的阻燃效果。     

环磷腈基无卤阻燃环氧树脂的合成及其性能

以六氯环三磷腈、对羟基苯甲醛和环氧氯丙烷为原料合成了一种环磷腈基环氧树脂(PNEP),利用核磁(NMR)及傅里叶红外光谱(FTIR)对其结构进行了表征。以PNEP为基体,分别用4,4'-二氨基二苯甲烷(DDM)与4,4'-二氨基二苯砜(DDS)为固化剂制备了两种环氧树脂固化物材料——DDM-PNEP和DDS-PNEP。通过极限氧指数(LOI)与热重分析(TGA)测试了材料的阻燃性能、热稳定性及成炭性能,并利用扫描电镜(SEM)对燃烧后残炭的形貌进行了表征。结果表明,制备的DDM-PNEP固化物具有更优异的阻燃性能,LOI可达27.1%;PNEP固化物初始热降解温度较低,DDM-PNEP为152℃,DDS-PNEP为159℃;主要热降解过程分两个阶段:DDM-PNEP为152~320℃和370~505℃两个阶段,DDS-PNEP为159~355℃和358~552℃两个阶段;DDMPNEP具有更好的成炭效果,600℃时残炭率为54.71%;SEM扫描测试结果表明,DDM-PNEP燃烧时形成的炭层致密均匀,能够起到良好的阻燃作用。     

分子间磷杂菲与磷腈双基协同阻燃环氧树脂研究

将六苯氧基环三磷腈(HPCP)和9,10–二氢–9–氧杂–10–磷杂菲–10–氧化物(DOPO)复合应用于阻燃环氧树脂(EP),通过极限氧指数和垂直燃烧性能测试、热失重分析、锥形量热分析等研究了其协同阻燃EP的性能,探讨了协同阻燃机理。结果表明,当DOPO在HPCP/DOPO复合阻燃剂中所占比例达到80%时,样品的阻燃级别达到UL94 V–0级,总热释放量降低,优于两种阻燃剂单独使用条件下对EP的阻燃效果,表明磷腈和磷杂菲两种阻燃剂之间存在着协同阻燃效应。     

环氧树脂和聚氨酯杂化物

将2种以上分子结构和性能各异的聚合物合成杂化物或改性物,是近年来聚合物技术的发展方向之一.简述了环氧树脂和聚氨酯杂化物的合成、改性原理及所得杂化物的主要应用领域.     

含磷羧酸类环氧树脂固化剂的合成及固化性能研究

以邻苯基苯酚和三氯氧磷为原料,无水三氯化铝为催化剂,首先合成9,10-二氢-9-氧杂菲-10-膦酰氯(ODC)。再以乙酸为溶剂,通过ODC与酒石酸(TA)的反应,合成了新型含磷羧酸类环氧树脂固化剂2,3-二9,110-二氢-9-氧杂菲-10-膦氧基)丁二酸(ODC-TA)。通过红外光谱、H核磁共振谱对ODC和ODC-TA的结构进行了表征,并通过DSC和TGA对ODC-TA/CYD-128型环氧树脂固化体系的固化性能及阻燃性能进行了研究。     

DGE-BHBTMBP/E-51/DDS固化物的研究

以4,4′-二氨基二苯基砜(DDS)为固化剂,用新型联苯芳酯型液晶环氧树脂[4,4′-双(4-羟基苯甲氧基)-3,3′,5,5′-四甲基联苯二缩水甘油醚](DGE-BHBTMBP)改性普通双酚A型环氧树脂(E-51),通过动态热机械性能分析、热重分析及扫描电子显微镜测试了DGE-BHBTMBP含量对DGE-BHBTMBP/E-51/DDS固化物的热性能和力学性能的影响。结果表明,加入DGE-BHBTMBP的E-51/DDS固化物的玻璃化转变温度(Tg)和初始分解温度都有所提高。加入质量分数为20%的DGE-BHBTMBP可使固化物的Tg和初始分解温度分别提高44℃和21.86℃。当其质量分数为4%时,固化物的力学性能明显提高,冲击强度和弯曲强度分别提高了136%和9%。     

氢氧化镁阻燃环氧树脂热降解性能研究

用氢氧化镁制备了阻燃环氧树脂复合材料,用极限氧指数(LOI)、烟密度等级(SDR)来表征其阻燃消烟性能,用热重仪和热重-质谱联用仪分析了氢氧化镁阻燃环氧树脂体系的热稳定性和热降解过程,并探讨了氢氧化镁阻燃环氧树脂的机理。结果表明:随着氢氧化镁用量的增加,复合材料的LOI不断提高,当氢氧化镁用量为47.37%时,环氧树脂/氢氧化镁阻燃体系的LOI达到27.5%,烟密度降至61.73%;氢氧化镁的加入使复合材料的最大热失重速率提高,促进了复合材料的迅速分解,使分解的温度区间变窄,降低了分解过程中二氧化碳、可燃性小分子、苯类和苯酚类物质的释放量。     

两种环氧树脂用磷氮阻燃剂的合成与应用研究

将4,4'-二氨基二苯甲烷(DDM)分别与苯甲醛和水杨醛进行缩合反应,所得两种缩合产物分别再与9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)进行加成反应,得到两种新型磷氮阻燃剂A和B,并通过红外吸收光谱(FTIR)、核磁共振(NMR)和质谱(MS)方法证实了产物的结构。结果表明:所得阻燃剂分子可以和DDM一起充当环氧树脂(EP)的固化剂。将阻燃剂A、B分别同DDM加入到EP中,固化后形成的环氧固化物的Tg值和热稳定性有小幅下降,而阻燃性能大幅提高:当环氧固化体系的含磷量为1.0%时,所有环氧固化物垂直燃烧等级均达到UL94 V-0级;当磷含量达到1.5%时,B的环氧固化物的极限氧指数(LOI)达到41.2%。     

Simultaneously Increasing Impact Resistance and Thermal Properties of Epoxy Resins Modified by Polyether-Grafted-Epoxide Polysiloxane

In this paper, polyether-grafted-epoxide polysiloxane (FEPMS) was synthesized via hydrosilylation among poly(methylhydrosiloxane) (PMHS), allyl polyoxyethylene polyoxypropylene ether (F6) and allyl glycidyl ether to modify Diglycidyl Ether of Bisphenol A (DGEBA). The morphology, thermal properties, and toughness of all cured samples were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and impact testing. Results indicated that grafted polysiloxane can be well dispersed in epoxy matrix, and the epoxy resin modified with FEPMS at relatively low addition levels exhibited higher thermal properties and improved toughness than the neat epoxy resin.     

三聚氰胺包覆聚磷酸铵阻燃环氧树脂的研究

研究了三聚氰胺包覆聚磷酸铵(MPP)与季戊四醇(PER)阻燃环氧树脂的燃烧性能。通过热重分析初步探讨了MPP/PER阻燃剂对环氧树脂的阻燃机理。结果表明:MPP/PER对环氧树脂具有很好的阻燃作用,能有效提高环氧树脂的氧指数和垂直燃烧性能,降低环氧树脂的热释放速率,使燃烧过程变得稳定,降低环氧树脂的火灾危险性。热重分析表明:添加了阻燃剂以后,环氧树脂的初始分解温度降低,残炭量显著增加,阻燃剂发挥了凝聚相阻燃的作用。     

聚碳酸酯改性环氧树脂的固化动力学与热性能研究

用动态DSC法研究了聚碳酸酯(PC)改性环氧树脂(EP)体系的固化行为,采用Flynn-Wall-Ozawa法分析了EP/PC体系固化活化能与转化率的关系,利用Kissinger和Crane方程研究了EP/PC体系固化动力学参数,并用TG和DSC研究了复合体系的热性能。结果表明:PC的加入没有改变EP的固化机理,反应级数基本不变,但是降低了EP固化物的热分解温度和玻璃化转变温度。     

Utilization of Granite Powder as Filler in PC-Toughened Epoxy Resins: Studies on Physico-Mechanical Properties

The present study reports the possibility of using granite powder, an industrial waste with no end use, as potential filler in polycarbonate (PC)-toughened epoxy resin. Testing data for the physico-mechanical properties such as tensile, flexural, density and void content of the composites, according to the filler loading were catalogued. Incorporation of waste granite powder in toughened resin enhances the mechanical properties when compared to neat epoxy, but reduces significantly with respect to toughened resin matrix.     

Synthesis and Comparative Physico-chemical Study of Polyester Polyols Based Polyurethanes of Bisphenol-A and Bisphenol-C Epoxy Resins

Polyester polyols of epoxy resins of bisphenol-A and bisphenol-C were synthesized by reacting corresponding 0.02 mol epoxy resin, and 0.04 mol ricinoleic acid by using 1,4-dioxane (30 ml) as a solvent and 0.5 g triethyl amine as a catalyst at reflux temperature for 4–5 hr. Polyurethanes have been synthesized by reacting 0.0029 mol of polyester polyols with 0.004 mol toluene diisocyanate at room temperature and their films were cast from solutions. The formation of polyester polyols and their polyurethanes are supported by IR spectral data (1732.9–1730.0 cm^?1 ester and urethane and 3440.8–3419.6 cm^?1 OH and NH str). The densities of polyurethane of bisphenol-A (PU-A) and polyurethane of bisphenol-C (PU-C) were determined by a floatation method. The observed densities of PU-A and PU-C are 1.2190 and 1.2308 g/cm³, respectively. Slightly high density of PU-C is due to structural dissimilarity of two bisphenols. The tensile strength, electric strength, and volume resistivity of PU-A and PU-C are 34.7, 18.7 MPa; 80.7, 44.4 kv/mm; and 1.7 × 10¹⁵, 2.2 × 10¹⁵ ohm cm, respectively. PU-A and PU-C are thermally stable up to about 182–187°C and followed three step degradation. Incorporation of cyclohexyl cardo group in polyurethane chain did not impart any change in thermal properties but it caused drastic reduction in tensile and electric strength due to rigid nature of PU-C chains. PU-C has excellent chemical resistance over PU-A. Both polyurethanes possess good resistance against water, 10% each of aqueous acids (HCl, HNO₃, and H₂SO₄), alkalis (NaOH and KOH) and NaCl. Good thermo-mechanical, excellent electrical properties, and good chemical resistance of polyurethanes signify their usefulness in coating and adhesive, electrical and electronic industries.     

Influence of Submicron TiO2 Particles on the Mechanical Properties and Fracture Characteristics of Cured Epoxy Resin

Submicron titanium dioxide (TiO₂) was used in different weight fractions as a toughening agent for amine-cured epoxy resin. After the use of X-ray photoelectron spectroscopy (XPS), which confirmed that the TiO₂ particles were evenly distributed in the cross-linked epoxy resin matrix, the composites were characterized by tensile and impact testing, followed by scanning electron microscopy of the fracture surfaces. The results indicated that the submicron TiO₂ toughening particles markedly improved the mechanical properties of the cured epoxy resin compared to the untoughened epoxy resin. The optimal properties were achieved at a TiO₂ concentration of 4 wt. %, at which point the toughness and the impact resistance values increased by 65% and 60%, respectively. The results also indicated that an increase in the amount of TiO₂ causes a decrease in toughness. Stress whitening, out-of-plane flaking, and thumbnail markings were the major visible features of the toughening mechanisms.

It is suggested that, at 4 wt. % of the submicron TiO₂ particles, microvoids are developed in the epoxy matrix. These microvoids are able to absorb some of the deformation work applied to the material, and thus enhance the toughness of the material. On increasing the TiO₂ content in the matrix (> 4 wt. %), the submicron particles got closer to each other and the microvoids were converted to macrovoids, which may act as stress concentrating flaws, leading to the deterioration of the mechanical properties of the epoxy resin.     

BaTiO3／环氧树脂／玻璃纤维复合材料介电性能研究

本文运用热压工艺制备了BaTiO3（BT）／环氧树脂／玻璃纤维和BaTiO3／炭黑／环氧树脂／玻璃纤维复合材料,研究了温度、填料含量和交流频率对复合材料的介电性能的影响。结果表明,复合材料的介电常数（εr）和介电损耗（tanδ）随肌体积分数的增加而升高。当肌体积分数为17％时,复合材料在1MHz下的εr和tanδ分别为7.88和0.027。当炭黑的含量为1.0％时,明含量为17％的复合材料εr和tanδ分别为11.0和0.035。随着频率的升高,复合材料的εr降低,而介电损耗升高。复合材料的εr随温度升高而增加。