耐高温保护膜压敏胶的制备及性能研究

王 虎¹，胡 维²，林克华³，陈其辉¹，洪茂椿¹，傅和青^1,2

（1.中国科学院福建物质结构研究所，福建 福州 350002；2.华南理工大学化学与化工学院，广东 广州  510640；3.福建友谊胶粘带集团有限公司，福建 福州  350300）

【摘  要】以丙烯酸丁酯（BA）、丙烯酸-2-乙基己酯（2-EHA）、甲基丙烯酸甲酯（MMA）、丙烯酸月桂酯（LA）为原料，β-羧乙基丙烯酸酯（β-CEA）为内交联剂，γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH-570）为改性剂，三甲基六亚甲基二异氰酸酯（TMDI）为固化剂，乙酸乙酯为溶剂，制备了一种高性能耐高温的溶剂型丙烯酸酯保护膜压敏胶。研究了内交联剂β-CEA、改性剂KH-570、单体LA和固化剂TMDI的添加量对保护膜压敏胶性能的影响。研究结果表明：当β-CEA的添加量为5%时，保护膜压敏胶的水接触角为75.2°，润湿性能最佳；当KH-570的添加量为2.5%时，保护膜压敏胶的吸水率最低为3.5%；随着单体LA和固化剂TMDI含量的增加，保护膜压敏胶的耐高温性能显著提高。当配方中w(β-CEA)=5%、w(KH-570)=2.5%、w(LA)=7%、w(TMDI)=2.0%时，保护膜压敏胶的水接触角为75.2°，吸水率为3.5%，初粘力为6号球，持粘力为24 h，180°剥离力为4.0 N/25 mm，在100 ℃下放置8 h后无残胶，在80 ℃、90%RH的条件下放置100 h不发泡。

【关键词】压敏胶；耐高温；丙烯酸酯；保护膜

新型双酚S衍生四官能度环氧树脂的制备及固化性能

杨志坚¹，李  鲲¹，范克凡¹，赵富贵¹，赵维维²，程  珏¹，张军营¹

（1.北京化工大学，碳纤维及功能高分子教育部重点实验室，北京  100029；2.异质多界面电磁功能结构胶接及封装联合实验室，中国航空工业集团公司济南特种结构研究所，山东济南  250023）

【摘  要】四官能度环氧树脂因其交联密度高而具有良好的耐温性和优异的力学性能，其中AG-80是综合性能较佳的高性能复合材料基体树脂。但是，结构特点导致AG-80存在韧性差、黏度高、储存不稳定、交联程度受限等问题，这在一定程度上限制了AG-80的使用工艺和固化性能的发挥。为了解决这些问题，本文设计并采用两步法合成了一种新型的四官能度环氧树脂——双酚S四官能度缩水甘油醚(SEP)。通过红外、核磁、质谱等确定了SEP的结构，采用差示扫描量热仪、热机械分析仪、动态热机械分析仪、热重分析仪等分析了SEP的固化行为及固化物的性能。研究结果表明：⑴与AG-80相比，SEP环氧树脂在25 ℃下的黏度更低，为52.56 Pa·s，这表明SEP环氧树脂具有更好的加工流动性。采用甲基六氢苯酐为固化剂时，SEP的固化温度比AG-80环氧树脂低，且储存更加稳定。⑵对比研究了SEP和AG-80改性双酚A环氧树脂（E-51）的性能，当SEP的质量分数为30%（SEP-30）时，其拉伸强度达到85.77 MPa，冲击强度达到18.74 kJ/m²；而AG-80在相同固化温度下的拉伸强度为68.25 MPa，冲击强度为12.61 kJ/m²，表明SEP体系的拉伸强度和冲击强度均比AG-80体系的高。通过SEM断面形貌进一步确定，SEP共混体系具有比AG-80体系更好的力学性能。⑶所有SEP共混体系的T_d5比AG-80体系的高。800 ℃下的SEP体系的残碳率最高达到16.9%，而AG-80体系在800℃下的残碳率最高达到9.9%，这表明SEP具有比AG-80更好的热稳定性。⑷与AG-80环氧树脂相比，SEP环氧树脂表现出更好的力学性能和耐热性能，为同时实现增强、增韧提供了可能，并使其有望在航空航天等高温领域得到较大的应用。

【关键词】四官能度环氧树脂；机械性能；热稳定性；甲基六氢苯酐

仿生聚天冬酰胺衍生物聚合物胶粘剂的制备及其性能

刘  华¹，蔡桂娣¹，王  博²

(1.山东宏旭化学股份有限公司，山东东营  257200；2.吉林工程技术师范学院生物质功能材料交叉学科研究院，吉林省秸秆基功能材料重点实验室，吉林长春  130012)

【摘  要】用于组织固定和伤口护理的生物胶粘剂的开发仍然是一个挑战。本研究采用聚琥珀酰亚胺为基体，引入三种不同组合的多巴胺(DOPA)、乙醇胺(EA)和疏水氨基辛烷(OA)，合成了聚天冬酰胺衍生物，并通过连续氨解反应分别制备了聚天冬酰胺衍生物PolyAspAm(DOPA/EA)和PolyAspAm(DOPA/OA/EA)胶粘剂。研究结果表明：⑴不同含水量的PolyAspAm(DOPA/EA)胶粘剂在玻璃基材上的拉伸剪切强度具有较大差异，且含水量降低，拉伸剪切强度变大。当PolyAspAm(DOPA/EA)胶粘剂中水分含量降低到7%时，拉伸剪切强度明显升高到0.6 MPa。⑵PolyAspAm(DOPA/OA/EA)胶粘剂在不同基材上的拉伸剪切强度均大于PolyAspAm(DOPA/EA)胶粘剂。在常用基材如玻璃、塑料基材（PMMA）和锡箔纸上，PolyAspAm(DOPA/OA/EA)胶粘剂的拉伸剪切强度可分别达到(0.36±0.032) MPa、(0.28±0.021) MPa和(0.29±0.024) MPa。⑶PolyAspAm(DOPA/OA/EA)胶粘剂具有较好的粘接稳定性，对玻璃基材应用14 d后，拉伸剪切强度达到最高值(0.65±0.029) MPa。⑷在PolyAspAm(DOPA/OA/EA)聚合物中引入物质的量为5%的高碘酸钠，可以提高胶粘剂的内聚力，对玻璃基材的拉伸剪切强度从(0.36±0.032) MPa提高到(0.51±0.039) MPa。

【关键词】生物胶粘剂；多巴胺；聚天冬酰胺；仿生；疏水

聚氨酯胶与玻璃界面粘接分子动力学研究

沈鹤飞¹，韩晓辉¹，尹承泽²，王  睿¹，郑自芹²，梁景恒²

(1.中车青岛四方机车车辆股份有限公司，山东青岛  266111；2.中国兵器工业第五二研究所烟台分所有限责任公司，山东烟台  264003)

【摘  要】为了研究界面分子对聚氨酯密封胶与玻璃界面的作用机制，本研究建立了聚氨酯胶/玻璃界面的微观结构模型。采用分子动力学模拟方法，从分子尺度上解释聚氨酯胶/玻璃粘接界面作用机制。研究了水分子和底涂剂主要成分对两者界面的影响，并通过拉伸剪切试验进行了验证。模拟研究结果表明：界面中水和底涂剂的添加能够提升聚氨酯胶在玻璃表面的吸附速率，其中底涂剂在聚氨酯分子向SiO₂表面运动的过程中充当了桥梁的作用，促使聚氨酯分子更快地吸附在SiO₂表面。通过计算三种构型的相互作用能发现，界面中水分子和底涂剂的存在会显著提升界面的结合能，使得聚氨酯分子更容易与SiO₂表面形成优良的粘接界面。拉伸剪切试验结果表明，高湿和底涂两种表面处理工艺确实能够改善胶接接头中聚氨酯胶和玻璃基材之间的界面结合性，试验结果与模拟结论相符。界面中水分子和底涂剂通过多种类型的相互作用，如远程的范德华力和近程的氢键、化学键等促进界面紧密结合，提升了聚氨酯胶/玻璃胶接接头的粘接性能。

【关键词】聚氨酯密封胶；界面作用机制；分子动力学模拟

温度对石英纤维增强中温固化环氧树脂复合材料性能的影响

鹿海军^1,2，张杜鹃^1,2，李亚锋^1,2

(1.中国航空制造技术研究院复合材料技术中心，北京  101300；2.先进复合材料重点实验室，北京  100095)

【摘  要】研究了温度对石英纤维增强中温固化环氧树脂复合材料性能的影响，对材料导热、热膨胀系数、力学性能以及介电性能等进行了表征。研究结果表明：组成复合材料的树脂和纤维在导热、热膨胀性能上具有明显差异，这是引起材料在受热过程中产生内应力的关键因素；干态条件下，在-50~80 ℃范围内，复合材料的强度随温度升高而降低，模量无显著变化，复合材料的力学性能稳定性良好；吸湿后材料的力学强度、模量均显著降低，长期湿热环境对复合材料树脂、纤维及二者界面均会产生显著破坏；不同温度下恒温后，AC319树脂和QW280/AC319复合材料的介电常数和损耗均随温度升高而增大，且介电损耗的变化幅度高于介电常数，材料极性基团的可动性（偶极取向能力）是决定树脂及复合材料介电常数和损耗的关键因素；树脂和复合材料的介电常数在升温跟踪过程中表现出相反的变化规律，树脂的介电常数先增后减最后趋于稳定，而复合材料的介电常数则先减后增再趋于稳定，主要由复合材料的界面层所致。

【关键词】温度；复合材料；力学性能；介电性能

球栅阵列（BGA）器件底填胶空洞测试方法及评估要求

张  晟，张晨晖，金  星，刘志丹

（西安导航技术研究所，陕西 西安  710068）

【摘  要】基于星载产品对导热绝缘胶可靠性应用，开展了球栅阵列（BGA）器件底填胶空洞测试方法及空洞率评估的准则研究。采用菊花链网络结构试验件，通过导热绝缘胶填充工艺验证，明确了空洞的来源过程，及各过程的主要影响因素。阐述了空洞对端机模块的影响机理及后果，根据空洞位置建立了3种空洞类型。采用工业射线计算机层析成像检测（CT）断层扫描成像系统及像素面积统计法，实现了大尺寸金属封装BGA器件底填胶空洞率的计算。研究结果表明：环境试验对空洞率有一定程度的增大影响，但该增大对菊花链试验件电性能基本没有影响；验证了菊花链试验件具有经受热循环、正弦振动、随机振动及热真空环境应力的能力，导热绝缘胶填充空洞率可以满足菊花链器件试验要求；明确了BGA器件导热绝缘胶填充空洞率的可靠性评估准则及判据示例，为填充工艺优化改进提供了指导依据。

【关键词】导热绝缘胶；BGA器件；菊花链；空洞率；工业CT；环境试验；评估准则

抗冲击UV固化密封胶的制备与性能研究

汪尧双，陆信航，王世伟，谢守华

（国光电器股份有限公司，广东省电声电子技术研发与应用企业重点实验室，广东 广州  510800）

【摘  要】通过使用不同的丙烯酸酯单体制备了不同的UV密封胶，对比了不同单体对胶粘剂力学性能、耐温性能、抗冲击力以及耐水性能的影响。研究结果表明：单体表面张力与胶粘剂对PC/PC剪切力成反比，胶粘剂耐温性能与单体的玻璃化转变温度（T_g）成正比，向胶粘剂中添加高T_g稀释剂单体，可以显著提升胶粘剂的耐温性能；胶粘剂的抗冲击性能受两方面影响，一方面受胶粘剂与基材的粘接力影响，另外一方面胶粘剂需要同时具备高屈服强度和高断裂伸长率，选用25%含量的丙烯酸异冰片酯（IBOA）单体抗冲击强度能达到最大化；胶粘剂单体中醚键含量越多，吸水率越高，耐水性越差，添加25%含量的双环戊烯基丙烯酸酯（DCPA）单体胶粘剂的耐水性能较好。

【关键词】抗冲击性；耐水性；稀释剂单体；UV密封胶

膨化聚四氟乙烯密封材料应用性能研究

李  言¹，窦 鹏¹，惠  鑫¹，任  杰²，龚海波²

（1. 中国航空制造技术研究院，北京  100024；2. 中国航空工业集团公司成都飞机设计研究所，四川 成都  610091）

【摘  要】对比分析了四种膨化聚四氟乙烯材料(A~D)的力学性能、尺寸收缩率、压缩应力松弛和密封性能，探讨了材料均匀性对密封效果的影响，并探究了材料均匀性与密封性能的构效关系。研究结果表明：密封材料C的拉伸强度、耐介质稳定性、高温抗压缩应力松弛性和短/长时密封效果均为最佳，其基本应用性能最好；密封材料A的尺寸收缩率、压缩应力松弛和短时密封效果均优于密封材料B，但是，密封材料A在多次重复密封试验中发生了泄漏；密封材料B的长时密封效果优于密封材料A。材料均匀性是决定膨化聚四氟乙烯密封材料长期密封效果的重要因素。在力学性能、尺寸收缩率、压缩应力松弛和力学性能结果相差不大时，材料均匀性越差，多次重复密封性能越差。因此，未来工程上在选取膨化聚四氟乙烯密封材料时，在参考材料基本应用性能指标的基础上，不同厂家材料的均匀性也是需要考虑的关键因素。

【关键词】膨化聚四氟乙烯；密封材料；密封效果；应用性能；材料均匀性

热熔压敏胶配方对自黏高分子防水卷材与后浇混凝土剥离强度的影响

贺 电

（中石化巴陵石油化工有限公司橡胶部，湖南 岳阳  414014）

【摘  要】以苯乙烯-异戊二烯-苯乙烯（SIS）、增黏树脂、增塑剂为原料，制备得到SIS热熔压敏胶。将其均匀涂布在HDPE片材上，制得所需自黏高分子防水卷材。考察了不同种类的SIS牌号、增黏树脂、增塑剂及其加入量对热熔型自黏高分子防水卷材与后浇混凝土剥离强度的影响，优化了自黏高分子防水卷材热熔压敏胶配方。研究结果表明：制备自黏高分子防水卷材热熔压敏胶的理想原料为SIS-1716、氢化C5石油树脂和聚异丁烯PB-950；最佳配方为100份总质量中，SIS-1716为30份，增黏树脂为53~55份，增塑剂PB-950为15~17份。此配方下制备的自黏高分子防水卷材与后浇混凝土的剥离强度可达3.60 N/mm以上。

【关键词】热熔压敏胶；配方；自黏；高分子防水卷材；剥离强度；影响

改善苯乙炔基封端聚酰亚胺加工性能的研究进展

刘彩召，张    松，张    斌，孙明明，张绪刚，李坚辉

(黑龙江省科学院石油化学研究院，黑龙江 哈尔滨    150040)

【摘  要】作为一类综合性能优异的有机高分子材料，聚酰亚胺广泛应用于航空航天、精密器械、汽车、电子电器等诸多领域。苯乙炔基封端聚酰亚胺具有耐温等级高、机械性能好、阻燃性优异、固化时无小分子释放等优点，但也存在熔融温度高、熔体黏度大、溶解度低等缺陷，限制了其应用范围。本文对改善苯乙炔基封端聚酰亚胺加工性能的研究现状进行了综述，并对其未来发展方向进行了展望。

【关键词】低黏度；溶解性；苯乙炔基；聚酰亚胺；加工性能

Preparation and performance study of high temperature resistance pressure sensitive adhesive for protective film

Wang Hu¹, Hu Wei²,Lin Kehua³, Chen Qihui¹, Hong Maochun¹,Fu Heqing^1,2

(1.Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, China; 2.School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou  510640, Guangdong, China; 3.Fujian Youyi Adhesive Tape Group Co., Ltd., Fuzhou  350300, Fujian, China)

【Abstract】With butyl acrylate (BA), 2-ethylhexyl acrylate (2-EHA), methyl methacrylate (MMA), and lauryl acrylate (LA) as raw materials, β-carboxyethyl acrylate (β-CEA) as internal crosslinking agent, γ-methacryloxypropyl trimethoxysilane (KH-570) as modifier, trimethylhexamethylene diisocyanate (TMDI) as curing agent and ethyl acetate as solvent, a kind of solvent-based acrylate pressure sensitive adhesive with high performance and high temperature resistance for protective film was prepared.The effects of addition amount of internal crosslinking agent β-CEA, modifier KH-570, monomer LA and curing agent TMDI on the performance of pressure sensitive adhesive for protective film were investigated. The research results showed that when the addition amount of β-CEA was 5%, the water contact angle of pressure sensitive adhesive for protective film was 75.2°, and the wetting performance was the best. When the addition amount of KH-570 was 2.5%, the water absorption rate of pressure sensitive adhesive for protective film was the lowest as 3.5%. With the increase of the content of monomer LA and curing agent TMDI, the high temperature resistance of pressure sensitive adhesive for protective film was significantly improved. In the formula, when w(β-CEA)=5%,w(KH-570)=2.5%, w(LA)=7% and w(TMDI)=2.0%,the water contact angle of pressure sensitive adhesive for protective film was 75.2°, the water absorption rate was 3.5%, the initial tack was No.6 ball, the holding power was 24 h, 180°peeling force was 4.0 N/25 mm, there was no residual after 8 h at 100 ℃, and it was not foamed at 80 ℃ and 90%RH for 100 h.

【Keywords】pressure sensitive adhesive; high temperature resistance; acrylate; protective film

Preparation and curing properties of new tetrafunctional epoxy resin derived from bisphenol S

Yang Zhijian¹,Li Kun¹,Fan Kefan¹,Zhao Fugui¹,Zhao Weiwei²,Cheng Jue¹,Zhang Junying¹

（1. Key Laboratory of Carbon Fiber and Functional Polymer, Ministry of Education, Beijing University of Chemical Technology, Beijing  100029, China; 2. Heterostructure Multi-Interface EFS Bonding & Encapsulation Technology Joint Laboratory, AVIC Research Institute for Special Structures of Aeronautical Composites, Ji’nan  250023, Shandong, China）

【Abstract】Tetrafunctional epoxy resin has good temperature resistance and excellent mechanical properties because of its high crosslinking density, among which AG-80 is the matrix resin of high-performance composite material with good comprehensive performance. However, the structural characteristics of AG-80 lead to problems such as poor toughness, high viscosity, unstable storage, and limited degree of crosslinking, which to a certain extent limits the use process and curing performance of AG-80. In order to solve these problems, a new type of tetrafunctional epoxy resin — bisphenol S tetrafunctional glycidyl ether (SEP) was designed and synthesized by two-step method in this paper. The structure of SEP was determined by infrared, nuclear magnetism resonance, mass spectrometry, and the curing behavior of SEP and the properties of cured product were analyzed by differential scanning calorimeter, thermo mechanical analyzer, dynamic thermo mechanical analyzer, thermogravimetric analyzer, etc.. The research results showed that: (1)Compared with AG-80, the viscosity of SEP epoxy resin was lower at 25 ℃, as 52.56 Pa·s, indicating that SEP epoxy resin had better processing flowability. When methyl hexahydrophthalic anhydride was used as the curing agent, the curing temperature of SEP was lower than that of AG-80 epoxy resin, and storage was more stable. (2)A comparative study was conducted on the properties of SEP and AG-80 modified bisphenol A epoxy resin (E-51). When the mass fraction of SEP was 30% (SEP-30), its tensile strength reached 85.77 MPa and impact strength reached 18.74 kJ/m². The tensile strength and impact strength of AG-80 at the same curing temperature were 68.25 MPa and 12.61 kJ/m², respectively, indicating that the tensile strength and impact strength of SEP system were higher than those of AG-80 system. Through SEM cross-sectional morphology, it was further determined that the SEP blending system had better mechanical properties than the AG-80 system. (3)The T_d5 of all SEP blending systems was higher than that of AG-80 system. The maximum carbon residue rate of SEP system at 800 ℃ was 16.9%, while the maximum carbon residue rate of AG-80 system at 800 ℃ was 9.9%, indicating that SEP had better thermal stability than AG-80. (4)Compared with AG-80 epoxy resin, SEP epoxy resin exhibited better mechanical and heat resistance properties, which provided the possibility of achieving reinforcement and toughening simultaneously, and had the potential to be widely used in high-temperature fields such as aerospace.

【Keywords】tetrafunctional epoxy resin; mechanical property; thermal stability; methyl hexahydrophthalic anhydride

Preparation and properties of biomimetic polyaspartamide derivative adhesive

Liu Hua¹, Cai Guidi¹, Wang Bo²

(1. Shandong Hongxu Chemical Co., Ltd., Dongying257200, Shandong, China;2. Jilin Provincial Key Laboratory of Straw-Based Functional Materials, Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University, Changchun  130012, Jilin, China)

【Abstract】The development of bio-adhesive for tissue fixation and wound care still remains a challenge. In this study, three different combinations of dopamine (DOPA), ethanolamine (EA) and hydrophobic amino octane (OA) were introduced, polyaspartamide derivatives were first synthesized by using polysuccinimide as the matrix, and then polyaspartamide derivatives PolyAspAm(DOPA/EA) and PolyAspAm(DOPA/OA/EA) adhesive were prepared through continuous ammonolysis reaction. The research results showed that: (1) The tensile shear strength of PolyAspAm(DOPA/EA) adhesive with different water contents on glass substrate was quite different, and the tensile shear strength increased with the decrease of water content. When the water content of PolyAspAm(DOPA/EA) adhesive decreased to 7%, the tensile shear strength increased significantly to 0.6 MPa. (2) The tensile shear strength of PolyAspAm(DOPA/OA/EA) adhesive on different substrates was greater than that of PolyAspAm(DOPA/EA) adhesive. On common substrates such as glass, plastic substrate (PMMA) and tin foil, the tensile shear strength of PolyAspAm(DOPA/OA/EA) adhesive could reach (0.36±0.032) MPa, (0.28±0.021) MPa and (0.29±0.024) MPa, respectively. (3) PolyAspAm(DOPA/OA/EA) adhesive had good bonding stability. After 14 days of application to glass substrate, the tensile shear strength reached the highest value as (0.65±0.029) MPa. (4) The introduction of 5% sodium periodate into PolyAspAm(DOPA/OA/EA) polymer could improve the cohesion of the adhesive, the tensile shear strength on glass substrate increased from (0.36±0.032) MPa to (0.51 ±0.039) MPa.

【Keywords】bio-adhesive; dopamine; polyaspartamide; biomimetic; hydrophobic

Molecular dynamics study on the bonding of polyurethane sealant to glass interface

Shen Hefei¹, Han Xiaohui¹,Yin Chengze², Wang Rui¹, Zheng Ziqin²,Liang Jingheng²

(1.CRRC Qingdao Sifang Co., Ltd., Qingdao 266111, Shandong, China; 2. Yantai Branch of China Ordnance Industry No.52 Research Institute Co., Ltd., Yantai  264003, Shandong, China)

【Abstract】In order to study the action mechanism of interface molecules on the interface between polyurethane sealant and glass, a microstructure model of polyurethane sealant/glass interface was established. The molecular dynamics simulation method was used to explain the action mechanism of polyurethane sealant/glass bonding interface at the molecular scale. The influence of water molecules and the main components of primer on the interface between them was studied, and verification was carried out through tensile shear test. The simulation research results showed that the addition of water and primer in the interface could improve the adsorption rate of polyurethane sealant on the glass surface, in which the primer acted as a bridge during the movement of polyurethane molecules towards the SiO₂ surface, promoting the faster adsorption of polyurethane molecules on the SiO₂ surface. By calculating the interaction energy of three configurations, it was found that the presence of water molecules and primer in the interface significantly enhanced the interfacial bonding energy, making it easier for polyurethane molecules to form an excellent bonding interface with the SiO₂ surface. The tensile shear test results showed that two surface treatment processes of high humidity and primer could indeed improve the interfacial bonding between polyurethane sealant and glass substrate in the bonding joint, and the test results were consistent with the simulation conclusions. The water molecules and primer in the interface promoted close interfacial bonding through various types of interactions, such as long range van der Waals force and short range hydrogen bond, chemical bond, improving the bonding performance of polyurethane sealant/glass bonding joint.

【Keywords】polyurethane sealant; interface action mechanism; molecular dynamics simulation

Effect of temperature on the properties of quartz fiber reinforced medium-temperature curing epoxy resin composite material

Lu Haijun^1,2, Zhang Dujuan^1,2,Li Yafeng^1,2

(1.AVIC MTI Composite Technology Center, Beijing  101300, China; 2.AVIC BIAM Key Laboratory of Advanced Composites, Beijing  100095, China)

【Abstract】The effect of temperature on the properties of quartz fiber reinforced medium-temperature curing epoxy resin composite material was studied, and the thermal conductivity, thermal expansion coefficient, mechanical properties and dielectric properties of material were characterized. The research results showed that the resin and fiber composing composite material had obvious differences in thermal conductivity and thermal expansion properties, which were the key factors causing internal stress in the material during heating. Under dry condition, in the range of -50~80 ℃, the strength of composite material decreased with the increase of temperature, the modulus did not change significantly, and the mechanical properties of composite material were stable. The mechanical strength and modulus of material decreased significantly after moisture absorption, and the long-term humid and thermal environment would cause significant damage to the resin, fiber and the interface of composite material. After constant temperature at different temperatures, the dielectric constant and loss of AC319 resin and QW280/AC319 composite material increased with temperature, and the change range of dielectric loss was higher than that of dielectric constant, the mobility of polar groups in the material (dipole orientation ability) was the key factor to determine the dielectric constant and loss of resin and composite material. The dielectric constant of resin and composite material showed opposite changes in the process of temperature tracking, the dielectric constant of resin increased first, then decreased and finally stabilized, while the dielectric constant of composite material decreased first, then increased and finally stabilized, mainly due to the interface layer of composite material.

【Keywords】temperature; composite material; mechanical property; dielectric property

Test method and evaluation requirements for underfill voids of ball grid array (BGA) device

Zhang Sheng, Zhang Chenhui, Jin Xing, Liu Zhidan

(Xi'an Research Institute of Navigation Technology, Xi′an 710068, Shaanxi, China)

【Abstract】Based on the reliability application of satellite-borne products for thermal insulation adhesive, the study of test method and evaluation for underfill voids of ball grid array (BGA) device was carried out. Using the daisy-chain network structure test piece, the source process of the voids and main influencing factors of each process were identified through the verification of thermal insulation adhesive filling process. The impact mechanism and consequences of voids on the end machine module were elaborated, and three types of voids were established based on voids position. The calculation of underfill voids rate of large-sized metal packaged BGA device was achieved using an industrial ray computed tomography (CT) imaging system and pixel area statistical method. The research results showed that environmental test had a certain degree of increasing effect on voids rate, but this increase had little effect on the electrical performance of the daisy-chain test piece. It was verified that the daisy-chain test piece had the ability to withstand thermal cycle, sinusoidal vibration, random vibration and thermal vacuum environmental stress, and the void filling rate of thermal insulation adhesive could meet the test requirements of daisy-chain device. The reliability evaluation criteria and examples of the criterion for void filling rate of BGA device with thermal insulation adhesive were clarified, which provided a guide for the optimization and improvement of the filling process.

【Keywords】thermal insulation adhesive; BGA device; daisy-chain; voids rate; industrial CT; environmental test; evaluation criteria

Preparation and performance study of impact resistance UV-curing sealant

Wang Yaoshuang, Lu Xinhang, Wang Shiwei, Xie Shouhua

（Guangdong Provincial Key Laboratory of Electroacoustic Electronic Technology R&D and Application, GuoGuang Electric Company Limited, Guangzhou  510800, Guangdong, China）

【Abstract】Different UV sealants were prepared by using different acrylate monomers, and the effects of different monomers on the mechanical properties, temperature resistance, impact resistance and water resistance of adhesive were compared. The research results showed that the surface tension of monomer was inversely proportional to the shear force of adhesive on PC/PC, and the temperature resistance of adhesive was directly proportional to the glass transition temperature (T_g) of monomer. Adding a high T_g diluent monomer to the adhesive could significantly improve the temperature resistance of adhesive. The impact resistance of adhesive was affected by two aspects. On the one hand, it was affected by the adhesion between adhesive and substrate. On the other hand, the adhesive needed to have both high yield strength and high elongation at break. The impact strength with 25% content of isobornyl acrylate (IBOA) monomer could be maximized. The more ether bond content in the adhesive monomer, the higher water absorption, and the worse water resistance. The water resistance of adhesive with 25% content of dicyclopentenylacrylate (DCPA) monomer was relatively good.

【Keywords】impact resistance; water resistance; diluent monomer; UV sealant

Study on application performance of expanded polytetrafluoroethylene sealing material

Li Yan¹, Dou Peng¹, Hui Xin¹,Ren Jie ², Gong Haibo²

(1.AVIC Manufacturing Technology Institute, Beijing 100024, China; 2.AVIC Chengdu Aircraft Design & Research Institute, Chengdu  610091, Sichuan, China)

【Abstract】The mechanical properties, dimensional shrinkage rate, compressive stress relaxation and sealing performance of four kinds of expanded polytetrafluoroethylene material (A-D) were compared and analyzed, the effect of material uniformity on the sealing effect was discussed, and the  structure-activity relationship between material uniformity and sealing performance was investigated. The research results showed that the tensile strength, medium resistance stability, high-temperature resistance to compressive stress relaxation and short/long-term sealing effect of sealing material C were all the best, and its basic application performance was the best. The dimensional shrinkage rate, compressive stress relaxation and short-term sealing effect of sealing material A were better than those of sealing material B. However, sealing material A leaked in several repeated sealing tests. The long-term sealing effect of sealing material B was better than that of sealing material A. Material uniformity was an important factor in determining the long-term sealing effect of expanded polytetrafluoroethylene sealing material. When there was no significant difference in mechanical properties, dimensional shrinkage rate, compressive stress relaxation and mechanical performance results, the worse the material uniformity, the worse the multiple repeated sealing performance. Therefore, when selecting expanded polytetrafluoroethylene sealing material in future engineering, based on the basic application performance indicators of material, the uniformity of material from different manufacturers was also a key factor to be considered.

【Keywords】expanded polytetrafluoroethylene; sealing material; sealing effect; application performance; material uniformity

Effects of hot melt pressure sensitive adhesive formulation on peeling strength of self-adhesive polymer waterproof roll material with post-cast concrete

He Dian

(Rubber Department, Sinopec Baling Petrochemical Co., Ltd., Yueyang  414014, Hunan, China)

【Abstract】Using styrene-isoprene-styrene (SIS), tackifying resin and plasticizer as raw materials, SIS hot melt pressure sensitive adhesive was prepared. It was evenly coated on HDPE sheets, and the required self-adhesive polymer waterproof roll material was obtained. The effects of different types of SIS grade, tackifying resin, plasticizer, and their addition amounts on the peeling strength of hot melt type self-adhesive polymer waterproof roll material with post-cast concrete were investigated, the formulation of hot melt pressure sensitive adhesive for self-adhesive polymer waterproof roll material was optimized. The research results showed that the ideal raw materials for preparing hot melt pressure sensitive adhesive for self-adhesive polymer waterproof roll material were SIS-1716, hydrogenated C5 petroleum resin, and polyisobutylene PB-950. The optimal formulation was 30 portions of SIS-1716, 53-55 portions of tackifier resin, and 15-17 portions of plasticizer PB-950 in the total mass of 100 portions.The peeling strength of self-adhesive polymer waterproof roll material prepared under this formula with post-cast concrete could reach over 3.60 N/mm.

【Keywords】hot melt pressure sensitive adhesive; formulation; self-adhesive; polymer waterproof roll material; peeling strength; effect

Research progress in improving the processability of phenylethynyl-terminated polyimide

Liu Caizhao, Zhang Song, Zhang Bin, Sun Mingming, Zhang Xugang, Li Jianhui

(Institute of Petrochemistry Heilongjiang Academy of Sciences, Harbin　　150040,Heilongjiang, China)

【Abstract】As a kind of organic polymer material with excellent comprehensive performance, polyimide is widely used in aerospace, precision instruments, automobiles, electronics and other fields. Phenylethynyl-terminated polyimide has the advantages of high temperature resistance, good mechanical properties, excellent flame retardance, and no release of small molecules during curing. However, there are also many defects such as high melting temperature, high melt viscosity and low solubility, which limit their application range. In this paper, the research status of improving the processability of phenylethynyl-terminated polyimide was reviewed, and its future development direction was prospected.

【Keywords】low viscosity; solubility; phenylethynyl group; polyimide; processability