共查询到20条相似文献,搜索用时 109 毫秒
1.
2.
3.
丁羟胶玻璃化温度的模拟计算 总被引:3,自引:0,他引:3
丁羟胶的玻璃化转变温度(Tg)预测对丁羟推进剂的贮存、运输和使用具有重要的参考意义。根据丁羟胶的主要性质搭建合理的无定形端羟基聚丁二烯(HTPB)结构模型,选用COMPASS力场、在恒温恒压(NPT)系综下,采用分子动力学(MD)方法模拟计算HTPB在不同温度时的比体积。研究结果表明,比体积与温度的关系曲线斜率在Tg处会发生转折;模拟计算得到的Tg为208.00K,采用差示扫描量热(DSC)法实测得到的Tg为194.86K,两种结果在误差允许范围内基本一致,表明MD法可以用来预测丁羟胶的Tg。 相似文献
4.
湿度对丁羟推进剂及其粘接性能的影响研究 总被引:11,自引:0,他引:11
付东升 《化学推进剂与高分子材料》2006,4(4):43-45
固体火箭发动机燃烧室内绝热层、人工脱黏层及推进剂药柱,均为高分子材料复合体系。在成型及贮存过程中,湿度是影响丁羟推进剂药柱性能及各界面的联合粘接强度的首要因素。探讨了绝热层、衬层及推进剂药柱在不同环境湿度下的吸湿特性,通过模拟实际生产过程的环境湿度,研究了丁羟推进剂药柱性能及各界面的联合粘接强度变化状况。 相似文献
5.
介绍了胶接件的表面处理以及胶黏剂的配制、涂胶、晾置、黏合和固化等因素对粘接强度的影响。表面处理介绍了常用方法,重点描述表面粗糙度与粘接强度的关系。胶黏剂的配制介绍了温度平衡、组分调整与预混、混合调配和配制顺序。涂胶介绍了涂胶方法和注意事项。晾置介绍了不同种类胶黏剂的晾置时间。黏合介绍了粘合方法和时机。固化介绍了固化方式、方法和固化条件三要素,重点描述固化温度、时间和压力与粘接强度的关系。 相似文献
6.
7.
综述了高拉伸强度高延伸率丁羟弹性体的几种改性方法。用自制的二聚脂肪酸二异氰酸酯(DDI)为固化剂制备的丁羟弹性体胶片具有优异的力学性能,最大拉伸强度达9.02 MPa,该强度下的延伸率达1 000%。指出以DDI为高性能固化剂的"DDI固化体系"是制备高拉伸强度高延伸率丁羟弹性体最为有效的途径,使用具有不同官能度的液体端羟基聚丁二烯进行复配的"丁羟双模体系"将是高强度高延伸率丁羟推进剂的主要研究方向。 相似文献
8.
9.
YW—1胶属双组份磷酸盐高强度耐热结构胶,在一定的结构粘接下,能获得很高的粘接强度,并能承受较高的温度。充分利用这些特点,能解决各方面的同题。多年来,已较普遍地应用于: 1、各种金属切削刀具(包括石油、煤炭地资钻头)。 2、各种专用精密量具。 3、冲压模(导柱、导套、凸模的粘接)。 4、铸件砂眼、气孔、裂纹的粘补。 5、设备制造及粘接修复。 6、重大废品的挽回等方面。粘接强度的高低,直接影响到应用,影响粘接强度的因素很多,主要的有下列几个方面: 一、粘接接头结构对粘接强度的影响 相似文献
10.
提高聚氨酯胶对玻璃钢粘接强度的研究 总被引:3,自引:0,他引:3
为了提高聚氨酯粘胶剂对玻璃钢的粘接强度,在聚氨酯胶粘剂配方中添加固化催化剂,在玻璃钢表面涂刷KH-550偶联剂,并且进行加速老化试验考核。结果表明,以上措施提高了粘接强度,能满足长期工作的需求。 相似文献
11.
12.
简述了推进剂与衬层界面黏结机理及造成界面附近推进剂软化的原因,总结了国内外关于影响端羟基聚丁二烯(HTPB)/异佛尔酮二异氰酸酯(IPDI)推进剂与衬层界面黏结性能因素以及改善界面黏结性能的技术途径的研究成果,提出了改善该类推进剂与衬层界面黏结性能的建议. 相似文献
13.
14.
以二官能团PUA(聚氨酯丙烯酸酯)为基体树脂、四氢呋喃丙烯酸酯为稀释单体、γ-缩水甘油醚基丙基三甲氧基硅烷(KH-560)为偶联剂、HCPK(1-羟基环己基苯基甲酮)为光引发剂和nano-SiO2(纳米二氧化硅)为填料,成功制备出一种UV(紫外光)固化胶。将UV固化胶用于PC(聚碳酸酯)塑料片材的胶接,并以该胶接件的T型剥离强度作为考核指标,采用单因素试验法优选出制备UV固化胶的较佳配方。结果表明:当w(二官能团PUA)=64%、w(HCPK)=3.0%、w(KH-560)=1.00%、w(四氢呋喃丙烯酸酯)=30%和w(nano-SiO2)=2.0%时,UV固化胶的剥离强度达到甚至超过市售同类产品(loctite3106)。 相似文献
15.
《Journal of Adhesion Science and Technology》2013,27(5):627-645
An acrylic adhesive was developed for forming strong, water resistant structural joints with polyolefins. This two-component, lightly crosslinked, methyl methacrylate (MMA) based adhesive consisted of an anaerobic curing system in one part with a copper (II) salt catalyst in the other. Bonds formed with low density polyethylene (LDPE) resulted in substrate failure upon block shear testing throughout the open time of the adhesive (45 min). The interdiffusion of the monomers into the substrates, and their subsequent polymerization was followed using several infrared spectroscopy (IR) techniques. The interphase of mixed LDPE and adhesive was determined to be as thick as 1.7 mm using IR microscopy. It was concluded that the strong adhesion in the aforementioned joints was the result of the interpenetration of the adhesive into the substrates. 相似文献
16.
17.
18.
Jingxin Na Liang Cai Shizhen Tao Yakun Yan 《Journal of Adhesion Science and Technology》2016,30(2):131-144
Traditional material joining techniques are facing enormous challenges due to the widely use of new materials in engineering. Therefore, the application of bonding technique in engineering becomes more and more important. In order to facilitate evaluation of the adhesive joint strength, a simple and efficient adhesive joint strength evaluation method which applies to engineering application was proposed in this paper. Tensile and shear stresses were selected as the main research objects in the method considering the complex working conditions that many adhesive structures may face in engineering. Butt joint, single-lap joint and several groups of scarf-joint specimens with different adhesive angles were fabricated. Numerous repetitive tensile tests were conducted to determine the adhesive failure stresses under different conditions. The adhesive failure stress envelope was fitted based on the experimental data and the evaluation method of adhesive joint strength was developed in detail. Finally, verification experiments were designed to determine the validity and reliability of the evaluation method. 相似文献
19.