聚硅氧烷型增容剂改性环氧体系的研究

本文用环氧树脂、瑞羟基聚二甲基硅氧烷等为原料,合成了增容剂,其可使聚二甲基硅氧烷有效地分散在环氧体系中而使环氧增韧。通过红外光谱测定、扫描电子显微镜观察,热失重分析及其他力学性能测试,对该体系的增容和增韧效果进行了研究。     

端羟基聚二甲基硅氧烷改性环氧树脂的研究

以端羟基聚二甲基硅氧烷(HTPDMS)改性环氧树脂(EP)能将热稳定和柔性的Si-O链引入环氧树脂固化的结构中,提高环氧树脂的综合性能.实验采用2-乙基-4-甲基咪唑作为环氧树脂的固化剂,添加不同质量分数的HTPDMS,实验结果表明:通过增容剂KH550的作用,HTPDMS可与EP发生反应,红外光谱分析表明有Si-O柔...     

环氧树脂—有机硅复合改性水性聚氨酯的合成

以异佛尔酮二异氰酸酯、端羟基聚二甲基硅氧烷、聚丙二醇、二羟甲基丙酸、环氧树脂为主要原料,通过异氰酸酯基和羟基的加聚反应合成了环氧树脂-有机硅复合改性水性聚氨酯。利用傅里叶变换红外光谱仪表征了其结构,并研究了环氧树脂用量对固化膜热性能和力学性能的影响,有机硅用量对固化膜耐水性能的影响。结果表明:环氧树脂-有机硅复合改性的水性聚氨酯固化膜的耐水性能和耐热性能提高,力学性能也有改善,附着力保持1级且硬度等级最高可达3 H。     

有机硅改性酚醛型环氧固化剂及其固化产物性能的研究

通过聚甲基三乙氧基硅烷(PTS)与环氧丙氧丙基三甲氧基硅烷缩合产物对线型酚醛树脂进行接枝改性,并将其改性产物用于固化环氧树脂。通过制备一系列不同比例改性酚醛树脂并分别与环氧树脂固化。所得的环氧固化产物进行冲击强度、玻璃化转变温度、热失重等测试,结果表明,改性固化产物比未改性固化产物玻璃化转变温度提高了约30℃,冲击强度最高提高了36.6%,高温热稳定性也显著增强。改性产物实现了热稳定性和韧性的综合提升。     

有机硅磷杂化改进环氧树脂耐热性、韧性和阻燃性的研究

将聚甲基三乙氧基硅烷（PTS）与一种合成的含磷硅烷偶联剂以一定配比进行反应,所得改性剂添加到双酚A环氧树脂E51/酚醛树脂固化体系中,对改性环氧树脂固化产物的玻璃化转变温度、热失重、冲击强度、拉伸强度、极限氧指数进行了测试,并对固化产物的表面形貌进行了SEM观察。结果表明,在保持拉伸强度基本不变的同时,改性环氧树脂固化物的玻璃化转变温度、高温热稳定性、冲击强度、极限氧指数均有不同程度提高,使改性环氧树脂的性能得到综合提升。     

动态固化聚丙烯／环氧树脂共混物的制备工艺研究

将动态硫化技术应用于热塑性树脂／热固性树脂体系，制备了动态固化聚丙烯／环氧树脂共混物，研究了动态固化PP／环氧树脂共混物制备工艺条件即增容剂、固化剂、环氧树脂的环氧当量及其含量等因素对共混物力学性能的影响。实验结果表明，选择马来酸酐接枝的均聚聚丙烯(PP-g-MAH)作为增容剂，所制得的动态固化PP／环氧树脂共混物的力学性能较好。2-乙基-4-甲基咪唑(EMI-2，4)的适宜用量为1．2％(每100份环氧树脂使用4份)。环氧当量对共混物的性能影响不大。当环氧树脂的含量为5％～10％时，动态固化PP／环氧树脂共混物的综合性能明显好于PP，特别是具有较高的强度和模量。     

硅烷／聚硅氧烷化学改性双酚A型环氧树脂研究

提出了一种有机硅改性电子封装用双酚A型环氧树脂新方法——用二氯二甲基硅烷(DMS)或其与。α，ω-二氯聚二甲基硅氧烷(DPS)的混合物来改性双酚A型环氧树脂；测定了固化物的冲击强度、拉伸强度、断裂伸长率、玻璃化转变温度等；用扫描电子显微镜观察了改性材料的断面形态。结果表明，环氧树脂经5．7份DMS或0．7份DMS、10份DPS改性后，均达到了很好的增韧和提高耐热性等效果，符合电子封装材料改性要求；后者的增韧效果更为显著，其断面SEM照片呈现特殊的褶皱状微团结构。     

端羟基聚二甲基硅氧烷改性环氧树脂研究

以端羟基聚二甲基硅氧烷(HTPDMS)与双酚A型环氧树脂(EP)为原料,异辛酸铋为催化剂,合成了一系列HTPDMS改性环氧树脂,采用红外光谱(FT-IR)确定了其化学结构。通过对固化物的固体含量分析,力学性能,水接触角及耐水性测试研究了HTPDMS用量对树脂性能的影响。结果表明,随着HTPDMS用量的增加,改性环氧树脂的拉伸强度和粘接强度有所下降,但断裂伸长率增大,耐水性能变好。     

PPGDGE对二次固化环氧树脂性能的影响北大核心

采用高温潜伏性固化剂超细双氰胺对环氧树脂E51/改性胺固化剂593体系进行高温二次固化,并用聚丙二醇二缩水甘油醚(PPGDGE)对该体系进行改性。通过力学性能、动态力学分析、形状记忆性能和扫描电子显微镜研究了二次固化和PPGDGE用量对环氧树脂体系的影响。结果表明:二次固化使环氧树脂强度大幅提高,拉伸强度为79.1 MPa,提高了47.9%;PPGDGE的加入使环氧树脂的形状记忆性能大幅提高,当加入9 phr PPGDGE时,冲击强度提高了28.0%,形状回复速率提高了52.8%,形状回复率提高了5.2%。     

活性增容剂对环氧沥青性能影响的研究

采用活性增容剂、固化剂、基质沥青和环氧树脂熔融共混,制备得到一种环氧沥青,研究讨论了增容剂用量对沥青和环氧树脂相容性、环氧沥青固化体系撕裂断面、低温收缩率、对钢板的粘结强度以及拉伸强度的影响.研究发现,增容剂可以将沥青以5μm大小的球状有效分散在环氧树脂中.随着增容剂含量的增加,材料低温收缩率有所增加,对钢板的粘结强度...     

Polydimethylsiloxane-Epoxy Copolymer for Industrial Applications

The copolymers of functionalized polydimethylsiloxane (PDMS) and epoxy resin were prepared by varying the concentration of PDMS with an objective to produce products with high-performance properties. These copolymers were cured using polyamide as a curing agent and characterized by FT-IR. The thermal properties and completion of curing were checked by DSC. The copolymers were evaluated for electrical and mechanical properties. The dielectric strength of the material increases with decrease in dissipation loss and dielectric constant. The mechanical properties were improved by 30–40 percent. The main objective was to reduce the brittleness and improve impact strength of epoxy systems.     

Preparation and Application of a New Curing Agent for Epoxy Resin

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.     

Epoxidized pine oil‐siloxane: Crosslinking kinetic study and thermomechanical properties

In this study, a novel approach to toughen biobased epoxy polymer with different types of siloxanes was explored. Three different modified siloxanes, e.g., amine‐terminated polydimethyl siloxane (PDMS‐amine), glycidyl‐terminated polydimethyl siloxane (PDMS‐glycidyl), and glycidyl‐terminated polyhedral oligomeric silsesquioxane (POSS‐glycidyl) were used as toughening agents. The curing and kinetics of bioepoxy was investigated by differential scanning calorimetry and Fourier transform infrared spectroscopy. The mechanical, thermal, and morphological properties of the cured materials were investigated. Rheological characterization revealed that the inclusion of POSS‐glycidyl slightly increased the complex viscosity compared to the neat resin. The morphology of the cured bioresin was characterized by transmission electron microscopy and scanning electron microscopy. The inclusion of POSS‐glycidyl to bioepoxy resin resulted in a good homogeneity within the blends. The inclusion of PDMS‐amine or PDMS‐glycidyl was shown to have no effect on tensile and flexural properties of the bioresins, but led to a deterioration in the impact strength. However, the inclusion of POSS‐glycidyl enhanced the impact strength and elongation at break of the bioresins. Dynamic mechanical analysis showed that the siloxane modified epoxy decreased the storage modulus of the bioresins. The thermal properties, such as decomposition temperature, coefficient of linear thermal expansion, and heat deflection temperature were improved by inclusion of POSS‐glycidyl. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42451.     

玉米秸秆木质素改性环氧树脂的制备与性能

将玉米秸秆木质素与双酚A环氧树脂混合,于100℃下预处理1 h,以改善环氧树脂的性能。对预处理后环氧树脂的黏度进行了测试,对改性环氧树脂与聚酰胺固化后材料的力学性能、动态力学性能、热稳定性以及燃烧性能进行了综合测试,考察了不同质量分数的玉米秸秆木质素对改性环氧树脂性能的影响。结果表明:以固化体系的总质量为基准,在w(木质素)=0~7%的范围内,与未添加木质素的环氧树脂相比,随着木质素质量分数的增加,改性环氧树脂22℃下的黏度从1 220 m Pa·s增大到13 220 m Pa·s;改性环氧树脂固化物的弯曲强度随木质素质量分数的增加先升高后降低,在w(木质素)=3%时达到最大值83.2 MPa,但其冲击强度下降,由20.7 MPa降低为13.6 MPa;改性环氧树脂固化物的玻璃化转变温度(Tg)随木质素质量分数的增加而增加,w(木质素)=5%时Tg提高了4.8℃;改性环氧树脂固化物的热稳定性有所改善,w(木质素)=7%时热失重50%的温度提高13℃,同时木质素的加入能够改善环氧树脂的阻燃性能。     

动态固化聚丙烯／马来酸酐接枝聚丙烯／滑石粉／环氧树脂复合材料研究

将动态硫化技术应用于热塑性树脂／填料／热固性树脂复合体系，制备了动态固化聚丙烯(PP)／马来酸酐接枝PP(PP-g-MAH)/滑石粉(Talc)／环氧树脂(EP)复合材料。研究了动态固化PP／PP-g-MAH/Talc／EP复合材料的界面作用、形态结构、力学性能以及热稳定性。实验结果表明：PP／PP-g—MAH的加入，可明显增加PP/Talc复合材料的界面作用。在动态固化PP／PP-g-MAH/Talc／EP复合材料中，PP和Talc两相界面更加模糊，动态固化EP进一步增加了PP和Talc间的界面作用。当EP的用量超过5份时，部分EP呈颗粒状分布在PP基体中。与PP／PP-g-MAH/Talc／EP和PP／PP-MAH-Talc／EP复合材料相比，动态固化PP／PP-g-MAH/Talc／EP复合材料的冲击强度、拉伸强度和弯曲模量均有明显提高。当EP用量超过5份时，复合材料的冲击强度和断裂伸长率明显降低，但拉伸强度和弯曲模量继续增加。热分析表明动态固化PP／PP-g-MAH/Talc／EP复合材料具有较高的热稳定性。     

含氟环氧树脂的合成与性能研究

采用十二氟庚醇与双酚A环氧树脂接枝合成了侧链含氟环氧树脂。采用了力学性能测试、红外光谱(FTIR)、X-射线光电子能谱(XPS)、动态热机械分析(DMTA)及交流阻抗分析(EIS)研究了含氟环氧树脂固化物的力学性能、表面性能及电化学性能等。结果表明,含氟环氧树脂固化后氟元素在表面富集,其断裂延伸率和冲击强度较双酚A环氧树脂分别提高41%和26.8%,交流阻抗提高2个数量级以上。含氟环氧树脂的韧性和电性能显著提高。     

Novel amine terminated elastomeric oligomers and their effects on properties of epoxy resins as a toughener

The objective of this study was to investigate the effects of amine terminated elastomeric epoxy tougheners on the mechanical and thermal properties of diglycidyl ether of bisphenol A based epoxy resin. The amine terminated polycaprolactone (PCL) (1) and PCL‐PDMS‐PCL (2) based oligomers were synthesized and characterized by FTIR spectroscopy. The stoichiometrical amount of the reactive oligomers as toughener, reactive epoxy resin and the curing agent, 4,4′‐diaminodiphenyl sulfone (DDS) were mixed and degassed. The homogenous mixtures were cured at 120°C into the preheated molds. The mechanical and thermal characterizations of toughened epoxy resin system were evaluated. It has been shown that the mechanical and thermal properties of toughened epoxy system vary as a function of the chemical structure and the concentration of rective oligomers. Higher mechanical properties were obtained for epoxy resin toughened by PCL‐PDMS‐PCL (2) based oligomer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Effect of molecular weight and content of PDMS on morphology and properties of silicone‐modified epoxy resin

To achieve a stable blend of a bisphenol A type epoxy resin and poly(dimethylsiloxane) (PDMS), reaction between hydroxyl (OH) groups of the epoxy and silanol groups of hydroxyl‐terminated(HT) PDMS has been investigated. The chemical structures of the HTPDMS‐modified epoxies were characterized by Fourier transform infrared (FTIR) and ¹H‐ and ¹³C‐NMR spectroscopy. To allow further understanding of the influence of viscosity and content of HTPDMS on the blend morphology, four different viscosities of HTPDMS were used in three content levels. The morphologies of modified epoxy resins were observed with optical microscopy. The modified epoxies were cured with a cycloaliphatic polyamine. The morphologies of modified epoxies were investigated by using scanning electron microscopy (SEM)/energy dispersive X‐ray (EDX) technique. The cured films showed droplet in matrix morphology with different mean droplets size which was influenced by the viscosity and the content of the incorporated HTPDMS. To illustrate the effect of the morphologies of the cured samples on mechanical properties, tensile strength tests were performed. The introduction of HTPDMS into the epoxy altered the tensile behavior according to its viscosity and content. Surface properties of the cured films were evaluated by sessile drop method. The results clearly indicate that the hydrophilic surface of the epoxy turns to a hydrophobic one due to the modification with HTPDMS. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.     

硅磷杂化物/环氧树脂固化物的性能研究

以γ-环氧丙氧基三甲氧基硅烷(KH-560)与磷酸反应合成了一种含磷硅烷偶联剂,将这种含磷硅烷偶联剂与硅溶胶按一定配比进行水解缩聚反应,得到一种硅磷杂化物,将该硅磷杂化物引入到双酚A环氧树脂(E-51),以4,4′-二氨基二苯基甲烷为固化剂,制备了硅磷杂化物/环氧树脂固化物。对该固化物的玻璃化转变温度、热失重、拉伸强度、极限氧指数(LOI)进行了测试。结果表明,该固化物玻璃化转变温度,700℃残炭量以及LOI均比纯环氧树脂固化物高,拉伸强度却下降较少。当硅磷杂化物的添加量占环氧树脂质量的50%时,该固化物的玻璃化转变温度可以达到178℃,极限氧指数可以达到28.2,与纯环氧树脂固化物相比,分别提高了18℃和25%。与纯环氧树脂固化物相比,该硅磷杂化物/环氧树脂固化物具有较好的阻燃性及热稳定性。