GO-g-PPE改性PA66复合材料的制备与性能

首先通过静电作用将氧化石墨烯(GO)与2,3–环氧丙基三甲基氯化铵(GTMAC)结合,再与马来酸酐(MAH)接枝聚苯醚(PPE)(PPE-g-MAH)发生反应,制得PPE接枝GO (GO-g-PPE)作为尼龙66 (PA66)材料的改性剂,采用共混挤出方式得到GO-g-PPE改性PA66复合材料。探讨了接枝前后的改性剂及添加量对复合材料力学性能、吸水率和摩擦性能的影响,采用扫描电子显微镜、差示扫描量热分析对复合材料界面相容性及热性能进行表征。结果表明,接枝后的GO-g-PPE与PA66的界面相容性明显优于仅添加GO/PPE的效果;当加入GO-g-PPE的质量分数≤0.8%时,随着GO-g-PPE用量的增加,GO-g-PPE改性PA66复合材料的力学性能有所提升,再继续增加GOg-PPE的用量反而使复合材料的力学性能下降。添加质量分数0.8%的GO-g-PPE时,GO-g-PPE改性PA66复合材料的热性能、力学性能最佳,与纯PA66相比,复合材料的结晶温度升高4℃,拉伸强度提高8.9%,断裂伸长率提高17.9%,缺口冲击强度提高37.6%;添加质量分数1.0%的GO-g-PPE时,复合材料的吸水率降低35.1%,摩擦系数减小14.3%。     

YY–503在无卤阻燃PPE/SEBS共混体系中的应用

系统研究了多功能粉体改性剂YY–503对无卤阻燃聚苯醚(PPE)/苯乙烯-乙烯/丁烯-苯乙烯嵌段共聚物(SEBS)共混体系拉伸性能、弯曲性能、加工流变性能、表面光泽度、白度和阻燃性能的影响。随着YY–503用量的增加,共混体系的拉伸强度、断裂伸长率、弯曲强度和弯曲弹性模量均呈现先增加后减小的变化趋势,其最大值分别为40.8 MPa,46.8%,62.8 MPa和2 281 MPa;共混体系的缺口冲击强度和表面光泽度随YY–503用量的增加逐步增大;共混体系的熔体黏度较高,YY–503的加入能延长塑化时间,但降低熔体黏度效果不理想;白度测试结果发现,当YY–503质量分数为1%时,共混体系的L值比与未添加时提高5.9%;当YY–503质量分数为0.5%~1%时,共混体系的阻燃等级达到V–0级。当YY–503质量分数为1%时,无卤阻燃PPE/SEBS共混体系具有良好的综合性能和较高的性价比。     

氰酸酯/G–POSS杂化材料的制备及性能研究

采用八环氧基笼型倍半硅氧烷(G–POSS)与双酚A型氰酸酯树脂(CE)共混制备了高性能CE/G–POSS杂化材料,考察了不同G–POSS含量时杂化材料的力学性能、热性能、介电性能和耐湿性。结果表明,G–POSS改性的CE断面存在大量波纹状和鱼鳞片状结构,增加了材料的韧性,当G–POSS含量为7份时,杂化材料的冲击强度达到最大值23.8 kJ/m2,比纯CE提高了158%;当G–POSS含量为4份时,杂化材料的介电常数由3.27下降到3.05,达到最小;随着G–POSS含量的增加,杂化材料的耐热性和耐湿性均有所下降。     

聚苯醚改性双马来酰亚胺三嗪树脂及其复合材料性能研究

由双马来酰亚胺(BMI)和氰酸酯(CE)树脂合成了一种高玻璃化转变温度(Tg)、低介电常数(ε)、低介质损耗因数(tanδ)的双马来酰亚胺三嗪树脂(BT树脂),并以高性能树脂聚苯醚(PPE)对其进行改性,制备了ε=2.76,tanδ=0.002 5的改性BT树脂.FTIR分析表明:CE、BMI分别自聚而成为各自均聚物,PPE以聚合物合金的形式分散在BT树脂中,BT树脂改性前后的DMA曲线均显示出两个玻璃化转变温度.由PPE改性BT树脂制备的复合材料具有优异的介电性能(ε=3.51,tanδ=0.005 5)和低吸水率(0.37%/24 h),改性BT树脂与玻璃纤维之间具有良好的界面黏结性能.     

PPE/EP体系的介电性能和耐溶剂性研究

利用扫描电镜、差示扫描量热仪以及高频介电仪研究了聚苯醚(PPE)/环氧树脂(EP)体系的相分离、耐热性和介电性能,并利用质量损失法研究了PPE/EP体系的耐溶剂性,结果表明:PPE/EP混合物的耐热性和介电性能均随着PPE含量的增加而提高,而耐溶剂性则随着PPE含量的增加而降低,在PPE/EP体系中加入三烯丙基异氰酸酯(TAIC)可有效地提高PPE/EP体系的耐溶剂性;当PPE含量大于30%时,PPE/EP混合物的介电性能显著提高,耐溶剂性显著下降。     

POSS/CE杂化复合材料的制备与介电性能研究

为制备介电常数(ε)低、介电损耗因子(tanδ)小的集成电路板用树脂基体,以笼型倍半硅氧烷(POSS)对双酚A型氰酸酯(CE)树脂进行改性,制备出一种POSS/CE无机-有机杂化复合材料。着重探讨了POSS用量和后处理工艺等对POSS/CE树脂体系介电性能的影响。结果表明:当w(POSS)=2%(相对于CE单体质量而言)、后处理工艺为240℃/3 h时,改性体系的介电性能相对最好,其测试频率为60 MHz时的ε(为2.9)和tanδ(为0.004 5)分别比纯CE树脂降低了9.4%和35.7%;该改性体系的表观活化能为51.9 kJ/mol。     

CE／HBPSi／GO复合材料的制备与性能

采用硅烷偶联剂表面处理的氧化石墨烯(GO)与氰酸酯树脂(CE)／超支化聚硅氧烷(HBPSi)共混制备了CE／HBPSi／GO复合材料,研究了GO含量对复合材料力学性能、介电性能、热稳定性和吸水率的影响。结果表明,添加适量GO可以有效提高CE／HBPSi的韧性和强度,还可以改善其介电性能、热稳定性和耐湿性。当GO的质量分数为0.8%时,CE／HBPSi／GO复合材料的冲击强度和弯曲强度达到最大值,分别为15.1 kJ／m2和131.6 MPa,并且该体系的介电常数、介电损耗角正切和吸水率均低于CE／HBPSi体系,热稳定性优于CE／HBPSi体系。     

端环氧基丁腈橡胶改性氰酸酯树脂性能的研究

采用端环氧基丁腈橡胶(ETBN)对双酚A型氰酸酯树脂(CE)进行改性,采用DSC和FT-IR表征了CE/ETBN树脂体系的固化行为和固化产物的结构,同时采用TGA和介电分析仪(DEA)对其耐热性和介电性能进行了研究。结果表明:ETBN的加入能显著促进CE的固化,改性体系的固化放热焓随着ETBN含量的增加而下降;CE/ETBN树脂体系的耐热性能随着ETBN含量的增加略有下降,当ETBN的质量分数为15%时,改性体系在N2气氛中的Td5为392℃,并且在80~140℃下其介电损耗正切值相对稳定。     

环氧树脂基类玻璃高分子在苯并噁嗪树脂改性中的应用及回收

使用环氧树脂基类玻璃高分子（EPV）对苯并噁嗪树脂进行改性,可以在保证聚苯并噁嗪树脂加工性能、热性能、强度的情况下,有效地提高聚苯并噁嗪的韧性,同时,高价值EPV回收对于节能减排具有重要意义。将双酚A-苯胺型苯并噁嗪与EPV按照不同比例共混固化,制备具有良好力学性能、热性能的聚苯并噁嗪改性体系,并对其中的EPV进行回收。使用傅里叶变换红外光谱仪、差示扫描量热分析仪、扫描电子显微镜等研究了共混体系固化过程中的反应机理、固化物化学结构和聚集态结构,通过动态热机械分析仪、万能试验机、电子悬臂梁冲击试验机研究了共混体系固化物的热力学性能、弯曲性能、韧性。结果表明,EPV的添加提升了共混体系固化物的力学性能和热性能,当添加EPV质量分数达到15%时,共混体系固化物的冲击强度可达到16.6 kJ/m²,比纯聚苯并噁嗪提高69.4%;当添加EPV质量分数达到20%时,共混体系固化物的玻璃化转变温度、室温下的储能模量、弯曲强度相比于纯聚苯并噁嗪分别提高了17℃,11.6%,43.1%。依靠动态酯交换反应从共混体系固化物中回收得到与纯EPV结构一致的EPV。     

环氧树脂基类玻璃高分子在苯并噁嗪树脂改性中的应用及回收

使用环氧树脂基类玻璃高分子（EPV）对苯并噁嗪树脂进行改性,可以在保证聚苯并噁嗪树脂加工性能、热性能、强度的情况下,有效地提高聚苯并噁嗪的韧性,同时,高价值EPV回收对于节能减排具有重要意义。将双酚A-苯胺型苯并噁嗪与EPV按照不同比例共混固化,制备具有良好力学性能、热性能的聚苯并噁嗪改性体系,并对其中的EPV进行回收。使用傅里叶变换红外光谱仪、差示扫描量热分析仪、扫描电子显微镜等研究了共混体系固化过程中的反应机理、固化物化学结构和聚集态结构,通过动态热机械分析仪、万能试验机、电子悬臂梁冲击试验机研究了共混体系固化物的热力学性能、弯曲性能、韧性。结果表明,EPV的添加提升了共混体系固化物的力学性能和热性能,当添加EPV质量分数达到15%时,共混体系固化物的冲击强度可达到16.6 kJ/m²,比纯聚苯并噁嗪提高69.4%;当添加EPV质量分数达到20%时,共混体系固化物的玻璃化转变温度、室温下的储能模量、弯曲强度相比于纯聚苯并噁嗪分别提高了17℃,11.6%,43.1%。依靠动态酯交换反应从共混体系固化物中回收得到与纯EPV结构一致的EPV。     

环氧及酚醛树脂增韧改性氰酸酯树脂研究

用环氧树脂(EP)及酚醛树脂(PF)对氰酸酯树脂(CE)进行增韧改性,对改性CE的凝胶时间和DSC曲线进行研究并确定了改性CE的固化工艺。红外光谱分析表明改性CE固化时形成了柔韧性结构。研究了改性CE的力学性能、热性能、电性能及微观形态,发现EP的加入可增加CE的柔韧性,PF的加入可使CE的热稳定性损失减小。当CE/EP/PF的质量比为70/15/15时改性CE的弯曲强度和冲击强度分别从改性前的123.6 MPa、5.2 kJ/m2提高到134.5 MPa、16.7 kJ/m2,耐热性及电性能改变不大。     

氰酸酯树脂/纳米氧化铜复合材料制备及性能

将无机纳米氧化铜(CuO)粒子加入氰酸酯树脂(CE),以有机锡(DBTDL)实现自由基引发,定量加入环氧树脂(E–54)制得CE/CuO系列复合材料。测试了复合材料的力学性能、导热性能和耐酸碱腐蚀性能,讨论了复合材料性能得以改变的原因。结果表明,无机纳米CuO粒子的引入,有利于CE基体树脂的聚合,无机纳米CuO粒子含量为10.0%时,复合材料差示扫描量热峰顶温度由286.3℃降至223.6℃,下降21.9%;无机纳米CuO粒子质量分数为6.0%时,复合材料弯曲强度达到165.36 MPa,较纯CE基体树脂提高了95.34%,复合材料冲击强度达14.18 kJ/m²,较纯CE基体树脂提高了62.24%;随无机纳米CuO粒子含量的增加,复合材料导热性能得以改善,当无机纳米CuO粒子含量为10.0%时,复合材料热导率增大10.24倍;无机纳米CuO粒子引入量为7.0%时,复合材料强碱腐蚀率为0.155%,比纯CE基体树脂下降38.0%;复合材料强酸腐蚀率为0.072%,比纯CE基体树脂下降60.4%。     

Preparation and properties of novel resins based on cyanate ester and hyperbranched polysiloxane

A novel kind of high performance cyanate ester (CE) resins was developed by copolymerizing 2, 2′-bis(4-cyanatophenyl) iso-propylidene with hyperbranched polysiloxane (HBPSi). HBPSi was synthesized through the hydrolysis of 3-(trimethoxysilyl)propyl methacrylate. The effect of the stoichiometry between CE and HBPSi on the structure and property of modified CE resins was investigated systematically. Results show that the incorporation of HBPSi can not only effectively promote the curing reaction of CE, but also increase the apparent free volume fraction of the cured network, and thus brings significant influence on the performances of the resultant resin. The impact strength of modified CE resin with 15 wt% of HBPSi is 19.6 KJ/m², which is more than 2 times of that of pure CE resin. In addition, the toughened CE resin also exhibits better thermal stability, dielectric property and moisture resistance than original CE resin. The novel modified CE system successfully overcomes the key shortcomings of original CE resin, importantly, this work demonstrates that the new method proposed in this work for modifying CE resin by hyperbranched polymers maybe a right road to be used for developing high performance thermosetting resins.     

Preparation and properties of cyanate ester modified by epoxy resin and phenolic resin

Stiff and brittle cyanate ester (CE) resin was modified by copolymerizing it with epoxy resin (ER) and phenolic resin (PR) to improve its toughness and flexibility. The cure process of the modified CE resin was characterized by gel time curves and differential scanning calorimetry curves. The Fourier transform infrared spectra of the modified CE resin showed its chemical structure during the curing process. The mechanical properties, thermal behavior, dielectric properties, and morphology of the modified CE resins were investigated. The results showed that an increase in epoxy and phenolic resins resulted in improved flexibility while maintaining thermal stability. When the mass ratio of CE/ER/PR was 70 : 15 : 15 (w/w), flexural strength and impact strength of the modified CE resin increased from 113.6 MPa and 5.2 kJ/m² to 134.5 MPa and 16.7 kJ/m², respectively. Little of the thermal stabilityand dielectric properties was sacrificed in the modification of the CE. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3150–3156, 2007     

Novel high‐performance wave‐transparent aluminum phosphate/cyanate ester composites

Advanced wave‐transparent composites are the key materials for many cutting‐edge industries including aviation and aerospace, which should have outstanding heat resistance, low dielectric constant and loss as well as good mechanical properties. A novel kind of high‐performance wave‐transparent composites based on surface‐modified aluminum phosphate AlPO₄(KH‐550) and cyanate ester (CE) was first developed. The dielectric and dynamic mechanical properties of AlPO₄(KH‐550)/CE composites were investigated intensively. Results show that AlPO₄(KH‐550)/CE composites have decreased dielectric loss and higher storage moduli than pure CE resin; in addition, the composites with suitable AlPO₄(KH‐550) concentration remain the outstanding thermal property and low dielectric constant of pure CE resin. The reasons attributing to these results are discussed from the effects of AlPO₄(KH‐550) on the key aspects such as morphology, curing mechanism, and interfacial adhesion of composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

环氧树脂/石英纤维透波复合材料制备

为改善环氧树脂的介电性能及提升石英纤维的界面性能,使用缩水甘油醚基笼型倍半硅氧烷(G–POSS)和γ–氨丙基三乙氧基硅烷(KH–550)分别对环氧树脂和石英纤维进行改性。利用差示扫描量热法研究改性后环氧树脂的固化过程,并通过外推法确定了其固化工艺,根据固化工艺制备环氧树脂/石英纤维复合材料,分别对该复合材料的热稳定性、介电性能和弯曲性能进行表征,结果表明,使用G–POSS和KH–550改性后的环氧树脂/石英纤维复合材料热稳定性、介电性能和弯曲性能达到最佳,初始分解温度达到369.59℃,常温下在12~18 GHz的介电常数稳定在3.2~3.5之间,介电损耗角正切值在0.005~0.02之间,弯曲强度达到376.4 MPa,弯曲弹性模量为21.7 GPa。     

Liquid crystalline epoxy resin modified cyanate ester for high performance electronic packaging

A high performance modified cyanate ester (CE) resin system with significantly improved toughness, water resistance and dimensional stability was developed by copolymerizing CE resin with liquid crystalline epoxy resin (LCE) for electronic packaging. Four LCE/CE resins with different contents of LCE were prepared to systemically evaluate the effect of the content of LCE on the key properties of the modified system such as mechanical, dielectric and thermal properties as well as water resistance. Results reveal that the addition of LCE to CE can not only decrease the curing temperature of CE, but also significantly improve the integrated properties including mechanical and dielectric properties, thermal resistance as well as water resistance of cured resin. For example, compared with the whole exothermic peak of CE, that of LCE10/CE significantly shifts toward low temperature with a gap of about 15°C. On the other hand, the impact strength of cured LCE10/CE resin (22 kJ/m²) is about 2.1 times of that of CE resin; while the water absorption of the former is only 81.2% of that of the latter. In addition, cured LCE/CE resins also exhibit lower and more stable dielectric loss than CE resin over the whole frequency range from 10 to 10⁶ Hz. All these improvements in macro-performance by the addition of LCE to CE resin are not only ascribed to the cross-linked chemical structure, but also attributed to the rigid structure of liquid crystalline resin. The outstanding integrated properties of LCE/CE resins suggest great potential to be applied in the field of high performance electronic packaging.