CR/MMA-AA自交联型接枝共聚物的合成与粘接性能研究

在交联单体Ｎ－羟甲基丙烯酰胺（Ｎ－ＭＡＡ）存在下,研究了氯丁橡胶（ＣＲ）／甲基丙烯酸甲酯（ＭＭＡ）－丙烯酸（ＡＡ）三元接枝共聚及产物性能,结果表明,在引发剂 为１．６￣２．０％,Ｎ－ＭＡＡ用量为２．２￣２．６％,ＡＡ（ＡＡ＋ＭＭＡ）（质量比）为１４％,反应时间为５ｈ,反应温度为８０￣８５℃时,产物的性能较优。对产物还进行了红外光谱表征和粘接性能测试。     

生体功能性医用材料止血功能的研究报告

对不同分子量、不同脱乙酰度、不同添加成分的甲壳素复合材料———五种生体功能性医用材料的止血功能进行了体外动态凝血和血小板粘附的探索试验和比较分析。     

生物材料表面改性抗细菌粘附的方法研究

为了减少生物材料中心的感染（BCI）,采用N2低温等离子体沉积（LTP）、二次等离子体、紫外（UV）辐照与化学方法相结合的实验技术,对人工心瓣用Dacron材料进行了改性。在其材料表面引入聚乙二醇（PEG）,利用PEG的“化学放大”作用再引入肝素(Hep),经表皮葡萄球菌（SE）体外动态粘附实验比较,紫外辐照与化学方法相结合的8改性抗细菌粘附效果最好,细菌粘附减少90％,二次等离子体改性次之,细菌粘附减少80％,N2低温等离子体沉积后抗细菌粘附效果有一定的提高。     

Application of the Blister Test in Study of Epoxy Adhesive

Shaft-loaded blister test technique is used as an effective quantitative tool to measure adhesion strength. Investigation on conductive adhesive was done by modified blister test. It is found that shaftloaded blister test can be a good solution for the debonding of thin film adhesion. The intrinsic stable interface debonding process has been proved an attractive alternative to the conventional adhesion measurement techniques. In our study, epoxy matrix adhesive was studied using blister test technique in comparison with the traditional test-lap shear test. Adhesion strength was studied as a function of surface treatment and the metallization of substrate. It was found that surface conditions of substrate have significant impact on adhesion behaviour. The oxidation of surface is responsible for the poor adhesion. Activating chemical treatment and Plasma cleaning on substrate surface has been found to be a way of dreamatically improving adhesion strength of electronic conductive adhesive.     

陶瓷涂层的力学性能测试

机械损伤是否产生取决于损伤驱动力及损伤抗力 ,对于陶瓷涂层而言 ,区别于单质固体的是 ,其损伤驱动力及损伤抗力二者都与材料本身相关 ,二者都受涂层与基体材料间的热学及力学匹配、涂层与基体材料的弹塑性性能、涂层的厚度及显微组织、以及涂层与基体界面的粗糙度等因素的影响。因此 ,涂层的热—机械行为的完整表征必须借助于基于破坏机制的损伤图才能完成。这种损伤图将相关参数有机地结合在一起 ,从而定出损伤安全区。而建立这种损伤图 ,必须有可靠的实验技术以测定涂层及界面的断裂韧性。而这种测试技术仍处于发展阶段 ,迄今并无完善的方法。作者正在研究及发展的多应变开裂及失稳试验 ,可能是目前最为简便易行而可靠的方法。本文略述测试与损伤图相关的参数的试验方法。     

Radio frequency plasma processing to produce chromium sputter targets

Production of thick chromium layers on copper substrates used for sputter targets provides a number of technological challenges. These challenges were addressed using radio frequency (RF) plasma spray technology. The efforts were focused on several objectives. The coatings should be as dense as possible with residual stresses low enough to avoid strong substrate bending and to prevent adhesive and/or cohesive failure of the coating. In addition, the deposition efficiency should be maximized. Different parameters were varied to find the optimum spraying conditions. Two different powder grain sizes, −90+45 μm and −63+20 μm, were used. First, a spheroidization study was performed to select the most suitable chamber pressure, the optimum plasma power, and a reasonable range of the powder feed rate. During deposition of the coatings, the powder feed rate, the spray distance, the substrate roughness, and the substrate cooling mode were optimized. The substrates were noncooled, gas cooled, or directly water cooled, respectively. The water-cooled samples showed no substrate bending; however, the thermal stresses occurring were strong enough to cause coating failure in adhesion or cohesion. Noncooled samples showed the best adhesion properties, while substrate bending could be kept within acceptable limits.     

Thermal spraying and adhesion of oxides onto graphite

Surface treatment of graphite (Cg), which is based on thermal spraying of oxides (Al₂O₃, ZrO₂), is proposed to reduce graphite reactivity and permeability toward oxygen. The study of coating adhesion allows recognition of the parameters that favor mechanical and chemical bonds. It also indicates the pretreatment of graphite, which leads to Cr₃C₂ or SiC bond coats. Different graphite-oxide systems were examined and showed that adhesion particularly depends on the thermal expansion coefficient mismatch between Cg, oxide, and the bond coat. Therefore, a post-treatment based on an impregnation with enamel of the porous oxide is essential to obtain effective protection of the graphite against the external environment.     

Interface reaction between nickel-base self-fluxing alloy coating and steel substrate

The interface reaction between a nickel-base, self-fluxing alloy coating and a steel substrate has been investigated to examine the formation of “pores,” which are observed along the interface of used boiler tubes. It was found that lumpy precipitates form along the interface instead of pores after heating at high temperatures and that the precipitates are of Fe₂B boride. The adhesion strength of the coating is not decreased by the formation of Fe₂B precipitates along the interface because of the increase of the adhesion due to interdiffusion.     

潮湿细粒物料的透筛粘附模型

从吸附理论的角度研究了潮湿细粒煤（水的质量分数为７％～１４％）在普通振动筛上分选时筛孔的堵塞机理;分析了细粒物料特性。如粒度及粒度分布、物料的团聚性等对透筛过程的影响;提出了潮湿细粒的物透筛粘附模型。结果变为：细粒物料的外在水分含量和粒度分布是影响筛分的主要因素;但当筛分理参数确定后,外在水分含量则显得更为重要。     

电晕放电处理对涤纶织物粘接性能的影响

本文通过光电子能谱和表面润湿实验来研究经电晕放电处理后的涤纶织物的表面性能,探讨了弱界面层和化学结构两种理论在粘合中的应用.