A Boron-based Adhesion Aid for Efficient Bonding of Silicone Rubber and Epoxy Resin

We improved the adhesion between silicon based insulating materials and epoxy resin composites by adding the adhesion promoter cycloborosiloxane(BSi,cyclo-1,3,3,5,7,7-hexaphenyl-1,5-diboro-3,7-disiloxane).The experimental results show that the addition of BSi in the silicone rubber(SR)system significantly increases the tensile shear strength between BSi and epoxy resin(EP),reaching 309%of the original value.On this basis,the mechanism of BSi to enhance the adhesion effect was discussed.The electron deficient B in BSi attracted the electron rich N and O in EP to enhance the chemical interaction,combined with the interfacial migration behavior in the curing process,to improve the adhesion strength.This study provides the design and synthesis ideas of adhesive aids,and a reference for further exploring the interface mechanism of epoxy resin matrix composites.

Flame-retardant Mechanism of Magnesium Oxychloride in Epoxy Resin

Flame-retardant mechanism of magnesium oxychloride （M OC） in EP was in-vestigated by limiting oxygen index （LOI）, XRD, SEM, TG-DTG and DSC. The results show that MOC performed well as an inorganic flame-retardant in EP. When the content of MOC is 50%, the LOI of EP reaches 29.6% and mass of residual char reaches 9.6%. The flame retarde mechanism of MOC is due to the synergies of diluting, cooling, catalyzing char forming and obstructing effects.

Study on Camellia Oleifera Protein based Wood Adhesive by Epoxy Resin and Its Crosslinking Mechanism

Epoxy resin (EPR) was used to crosslink with Camellia oleifera Abel.protein to prepare wood adhesive,and the bonding performance and curing characteristics of which were mainly investigated,and the synthesis mechanism was also discussed by using model compounds.The experimental results show that EPR can significantly improve the bonding performance of Camellia oleifera Abel.protein-based adhesive,and the maximum of which reaches 0.72 MPa satisfies the strength requirement of Type II plywood in GB/T 17657-2013.After alkali treatment,the protein can more easily crosslink with EPR at low curing temperature,and the adhesive has high degree of crystallinity of curing products,high degree of crosslinking reaction,and high bonding strength.The reaction mechanism of EPR-modified Camellia oleifera Abel.protein adhesive can be divided into resinification phase and curing phase.

Determination of Water Diffusion Coefficients and Dynamics in Adhesive/Carbon Fiber Reinforced Epoxy Resin Composite Joints

To determinate the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints, energy dispersive X-ray spectroscopy analysis（EDX） is used to establish the content change of oxy- gen in the adhesive in adhesive/carbon fther reinforced epoxy resin composite joints. As water is made up of oxygen and hydrogen, the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints can be obtained from the change in the content of oxygen in the adhesive during humidity aging, via EDX analy-sis. The authors have calculated the water diffusion coefficients and dynamics in the adhesive/carbon fiber reinforced epoxy resin composite joints with the aid of beth energy dispersive X-ray spectroscopy and elemental analysis. The de- termined results with EDX analysis are almost the same as those determined with elemental analysis and the results al- so show that the durability of the adhesive/carbon fther reinforced epoxy resin composite joints subjected to silane cou- pling agent treatment is better than those subjected to sand paper burnishing treatment and chemical oxidation treat- ment.

600 Mesh Silicon Carbide Corona Protection Varnish with EPOXY/OMMT Nano-composite Adhesive

A new corona protection varnish was prepared by using epoxy/montmorillonite nanocomposite and pure epoxy resin as adhesives respectively.The adhesive with different amounts of organic montmorillonite（OMMT） was mixed with 1200 mesh silicon carbide（Si C） by different weight ratios.The surface states of the varnishes with various adhesives were observed by powerful optical microscope.Some properties of the varnishes were analyzed during the enduring time under 5kV/cm DC,such as the relation of change in nonlinear coefficient,natural surface resistivity,and surface temperature variation.The results showed that the amounts of OMMT had little effect on the natural surface resistance of the varnish but had important influence on the nonlinear property of the varnish.When the range of the OMMT content was 2wt% to 6wt%,the nonlinear coefficient of all materials with epoxy/OMMT nano-composite adhesive was higher than that with pure epoxy resin adhesive.The surface temperature of the varnish with epoxy/OMMT nanocomposite adhesive was all lower than that with the pure epoxy resin adhesive under high electrical field strength.

Preparation of the Heat Resistant Adhesive of NBR Modified BMI

A Kind of homogeneous resin , which can be used as thermal resistant adhesive and matrix for composite, was prepared by bis (4-maleimidophenyl) methane ( BMI), 4,4’ -diaminodiphenylmethane( DDM), aniline (An), phenol type epoxy resin ( F-51 ) and nitrile -butadiene rubber ( NRR) through solution copolymer-ization . The reaction from prepolymerization to curing of the resin system was studied. And the factors such as raw material ratio and curing temperature, which affect thermal resistance and adhesives of cured product, were also analyzed. SEM and IR spectra were utilized to discuss the mechanisms of toughness and reaction of modified BMI.

水利工程用环氧树脂改性聚氨酯丙烯酸酯性能研究

水利工程金属结构和水工建筑物常遭受腐蚀、高速含沙水流磨蚀破坏,需对其进行便捷有效的防护。利用环氧树脂对聚氨酯丙烯酸酯(PUA)进行改性提高PUA与基体黏结性能,采用紫外光(UV)固化技术制备PUA涂层。研究了环氧树脂改性PUA的化学结构及环氧树脂用量对PUA的力学性能、热稳定性能、耐溶剂性能和抗冲磨性能的影响。结果表明,环氧树脂改性PUA的拉伸强度随着环氧树脂用量增加,呈下降趋势,当加入5%时,PUA拉伸强度为103.0 MPa,材料呈强而脆的特性。环氧树脂加入提升了PUA的拉伸剪切强度,由0.25 MPa增至1.60 MPa。同时,环氧树脂改性PUA具有良好的耐水性能、耐溶剂性能、抗冲磨性能,5%环氧树脂改性PUA抗冲磨强度为800 h/(kg·m^(2))。

混凝土加固施工中的环氧树脂胶改性及效果研究

针对传统混凝土施工中环氧树脂胶质脆韧性不足和高温易流挂的问题,提出通过气相白炭黑(MSD)对传统环氧树脂结构胶进行改性。试验结果表明,在酚醛胺固化剂T-31掺量为15%,聚酰胺固化剂PA掺量为40%,硅烷偶联剂KH-792的掺量为3%,超细石英砂掺量为40%,纳米碳酸钙掺量为20%,MSD掺量为3%;短切碳纤维掺量为6%配比下制备的结构胶性能最佳。14 d压缩强度、拉伸强度、正拉粘接强度和拉伸抗拉强度分别为81、34、5.5和18.5 MPa。表现出良好的阻裂粘接性能,可以在桥梁混凝土加固中发挥重要作用。

无枝状结晶耐离子迁移覆盖膜的研究

挠性印制电路板(FPCB)的离子迁移主要受挠性覆铜板(FCCL)和覆盖膜胶层的影响,表现为线路间的枝状结晶。考察采用环氧胶、聚酰亚胺胶等胶黏剂制备覆盖膜的耐离子迁移性,观察耐离子迁移性测试后的试样形貌,发现不同类型胶黏剂制备的覆盖膜试样枝状结晶程度不一,其中普通环氧胶覆盖膜试样线路间枝状结晶严重。进一步通过胶黏剂配方研究,开发出一种无枝状结晶的环氧胶覆盖膜,性能满足IPC-4203标准要求。

混凝土外墙面装饰用改性环氧树脂胶粘剂制备及应用

为了提高建筑外墙装饰用混凝土胶粘剂性能。以环氧树脂为原料,以乙酸乙酯为稀释剂,以三苯基膦盐为固化剂制备了建筑外墙装饰用混凝土环氧树脂胶粘剂,并对其性能进行了测试表征。结果表明,冷环境下,随着温度降低混凝土与砖板粘接试件的粘接强度、剥离强度不断下降,冲击强度极速下降,而剪切强度变化并不显著;热环境下,随着温度升高试件的粘接强度、剪切强度、冲击强度并未显著变化,而剥离强度缓慢下降;湿环境下,随着湿度增加试件的粘接强度、剥离强度、剪切强度、剪切强度均明显下降;随着挠度增大,试件的抗压强度呈现为显著变大趋势;环氧树脂胶粘剂表观性能与环保性能表现优异,且整体承载力与抗压强度明显提高。

纳米纤维融合改性建筑结构胶制备及性能测试

为提高建筑结构胶性能,通过在传统建筑结构胶中加入纳米纤维材料,制备了一种具有较高应用性能的新型建筑用结构胶。新型建筑结构胶通过在微硅粉和纳米二氧化硅中加入纳米碳酸钙和纳米白炭黑,实现了对建筑结构胶环氧树脂结构胶的改性。当掺入的固定剂质量分数为50%,偶联剂4%,稀释剂10%,组合填料掺量为5%时,可获得抗压强度、抗拉强度等力学指标最佳的建筑结构胶。相对于加入传统的纳米二氧化硅,试验加入的组合填料对结构胶的改性更好。

环氧树脂胶粘剂化学改性方法研究进展

环氧树脂是一种应用广泛的胶粘剂材料,但传统环氧胶粘剂往往达不到如今多样化的性能需求,需要改性后使用。本文从环氧胶粘剂固化关键成分的角度,分类综述了近十年来环氧胶粘剂化学改性方法,如新型环氧树脂和固化剂的合成、复合改性等。结合近几年的研究热点,对环氧胶粘剂未来的发展方向进行了分析和展望。

纤维素基环氧树脂及其木材胶粘剂粘接性能研究

以碱活化的纤维素为原料,通过与环氧乙烷(EO)发生接枝液化反应,合成了液体纤维素基环氧树脂(PHECEP)。然后以E-51为基体树脂,胺类T31为固化剂,硅微粉、硅烷偶联剂KH-560和PHECEP为改性剂,制备纤维素基环氧树脂胶粘剂,并对其进行力学性能、热性能和耐化学性等测试。研究结果表明:在PHECEP掺入量为20%时,抗冲击强度从2.9 kJ/m^(2)提升到50.9 kJ/m^(2);当PHECEP掺入量为5%时,室温下固化7 d的纤维素基胶粘剂拉伸剪切强度比纯E-51提高了171.1%。掺入PHECEP后,实际拉伸剪切强度高于测试中的强度,并且在小分子溶剂中耐受性更优良。通过PHECEP/E-51材料的力学性能、干湿粘接强度、热稳定性和耐化学性等性能的综合评判,得到相对最优的木材胶粘剂配方为:5%PHECEP(相对于E-51质量而言),1%的KH-560、60%的硅微粉和18%的T31固化剂(分别相对于PHECEP和E-51总质量而言)。

环氧树脂胶粘剂对混凝土裂缝修复性能的影响研究

研究使用环氧树脂胶粘剂修复混凝土裂缝问题,分析环氧树脂胶粘剂对于混凝土结构力学性能的影响,使用丁腈橡胶改性环氧树脂,增加环氧树脂韧性,并与稀释剂、固化剂混合制备修复混凝土的环氧树脂,将该环氧树脂灌注在预制裂缝的混凝土试件中,通过万能试验机等设备测试修复前后试件的抗压、抗折强度变化,并验证丁腈橡胶用量对于修复效果的影响。结果表明,使用改性环氧树脂修复混凝土多种形式的裂缝,能够提升混凝土抗压、抗折强度的恢复率,降低液体向混凝土入渗的速度,提升混凝土的性能,同时在环氧树脂中添加丁腈橡胶8 phr能够提升修复的耐水性。

缓凝粘合剂在建筑结构缓粘结预应力混凝土中的应用

为研究建筑结构缓粘结预应力混凝土中缓凝粘合剂的应用配比,将固化剂与硅胶按照2∶100的比例配制成胶液,浇注后使其固化获得制备好的硅胶模具,应用试验材料制备缓凝粘合剂,设计10种邻苯二甲酸二丁酯与环氧树脂的混合比例,制备10种不同的样品,分2批配制缓凝砂浆,用于包裹预应力筋,当混凝土试块浇筑9 d后,对缓粘结预应力筋实施张拉操作。依照配比的顺序共制备30个缓粘结预应力混凝土试件。结果表明,当邻苯二甲酸二丁酯加入量为25、20 g,环氧树脂加入量为120、125 g时,缓粘结预应力混凝土试件的力学性能与抗震性能均较好。

环氧/聚酯复合树脂导电银浆的制备与研究

通过环氧树脂与聚酯树脂共混方法,研究了不同共混树脂银浆的流变、导电和力学特性。采用流变仪对树脂银浆的触变性和触变恢复率进行了探讨,进而讨论了流变性对印刷膜层的影响。原位电阻测试法对树脂银浆热固化电阻变化情况进行了监测,结果显示银浆中环氧树脂的含量对电阻有较大的影响。采用推力测试方法对树脂银浆在Al_(2)O_(3)基板的附着强度进行了评价,并评测了树脂银浆的热冲击性能。研究结果显示C-1银浆在环氧树脂和聚酯树脂含量比为1∶0.6时,粘度适中,10 s后触变恢复率58.03%,印刷表面平整;200℃固化30 min电阻为2Ω左右,附着强度约为10 N/mm^(2),经260℃热冲击附着强度无明显劣化,综合性能较优,适用于电子元器件的工艺要求。

一种无溶剂型电子封装用导电胶的研制

为了解决导电胶黏剂因综合性能不足而导致大规模应用的受限,本文以酚醛环氧、多官能环氧为导电胶树脂基体,选用了4,4′-二氨基二苯砜(DDS)作为固化剂,片状银粉作为导电填料,通过调节银粉和固化剂的用量,制备了有良好流变性、导电性、力学性能的导电胶。通过分析测试,得到导电胶的黏度为32 800 mPa·s,触变指数为4.0,体积电阻率为4.34×10^(-4)Ω·cm,剪切强度为17 MPa,热导率为3.96 W/(m·K),Cl^(-)、Na^(+)和K^(+)分别仅为6.79×10^(-5)、6.31×10^(-5)和<10^(-5)。该导电胶综合性能优异,可应用于电子元器件及其他导电导热功能性材料的粘接。

高温环境下建筑加固用环氧树脂结构胶粘接性能分析

研究高温环境下建筑加固用环氧树脂结构胶粘剂粘接性能。采用环氧树脂、低分子聚酰胺、丁基缩水甘油醚以及不同掺量的KH-550硅烷偶联剂,制备3种建筑加固用环氧树脂结构胶试件。结果表明,在高温环境下,偶联剂添加量分别为4%与6%的试件拉剪强度、粘接强度更好。添加2%偶联剂试件在较高温度下粘接性能下降幅度相对较大;添加4%偶联剂试件的导热性能较强,说明环氧树脂结构胶粘剂在添加4%偶联剂时粘接性能最佳。

电机封装用改性环氧树脂胶粘剂绝缘与导热性分析

为提升环氧树脂胶粘剂的导热性能,为电机绝缘封装材料建立一个优良的导热环境,研究通过KH560偶联剂对h-BN导热材料实施改性处理,并将经过改性处理的h-BN导入桐马环氧胶结剂并制备出h-BN/EP复合材料。为验证该材料的应用性能,采用扫描电子显微镜、稳态热流仪等设备来分析该材料的表现微观形貌、导热性能和绝缘性能。经试验研究发现,当h-BN填量达到30%时,复合材料的导热率可达到0.424W/(m·K),相较纯环氧树脂增加了170.2%,且击穿电场与纯环氧树脂相当。说明该材料在有效提升环氧树脂导热性能的同时保留了其优良的绝缘性能,具有一定的应用价值。