环氧树脂/滑石粉、纳米蒙脱土水下胶粘剂研究

主要研究了滑石粉、有机化处理蒙脱土作为填料对水下环氧胶粘剂拉伸剪切强度的影响及蒙脱土与滑石粉协同作用效果,依此推荐了水下环氧胶粘剂的组份。     

化妆品中滑石粉在国内外的监管概况

介绍了滑石粉的毒理信息,分析了中国、欧盟、美国和加拿大化妆品法规对化妆品中滑石粉及该原料中杂质石棉的有关要求,并对其安全性予以评价,以帮助监管机构和相关企业了解其危害,提升消费者对滑石粉的认知度。     

滑石粉处理阳离子染料废水的试验研究

研究滑石粉吸附去除水中阳离子染料的可行性.选取亚甲基蓝、结晶紫、中性红3种阳离子染料,考察染料废水浓度、滑石粉投加量、反应温度、搅拌时间等因素对滑石粉净化染料废水的影响,确定最佳吸附条件.结果表明,当染料质量浓度为0.015 g/L、滑石粉投加量为10g/L、温度为20℃、慢速搅拌时间为10 min时,3种染料废水的脱...     

微波消解-电感耦合等离子体质谱法测定儿童爽身粉中微量硼

利用微波消解前处理法,通过优化前处理和检测条件,针对儿童爽身粉(三岁以下)中不得检出硼酸和硼酸盐的规定,探索了一种电感耦合等离子体质谱(ICP-MS)法测定儿童爽身粉中的微量硼,实现了对硼元素在低质量浓度0~20 ng/mL范围内的准确定量。通过优化,最终选择HNO₃^-H₂O₂消解体系,消解程序为最终温度185℃,保持30 min,仪器分析模式为Nogas模式;同时考察了样品中共存离子的干扰情况。结果表明,Na⁺、K⁺、Ca²⁺、Mg²⁺、Fe²⁺、Al³⁺、Pb²⁺、Zn²⁺对硼的测定不产生干扰。该方法中硼的线性相关系数(r)为0.9999,检出限为0.02μg/g,定量限为0.07μg/g。在低、中、高三个质量浓度水平下的加标平均回收率为99.2%~101.4%。在阳性样品中,测定值的相对标准偏差RSD(n=6)为1.3%。实验结果表明,该方法准确、可靠、灵敏度高,适用于儿童爽身粉中硼酸和硼酸盐的测定,有助于加强对儿童爽身粉中硼酸和硼酸盐的风险管控。     

低温等离子体处理对PBO纤维润湿性的影响

为改善PBO纤维的润湿性,拓宽其应用领域,探究了空气低温等离子体处理对PBO纤维润湿性的影响。通过芯吸效应和接触角表征处理前后PBO纤维润湿性,并采用扫描电子显微镜SEM观察处理前后PBO纤维表面形貌,用X射线光电子能谱仪(XPS)对处理前后PBO纤维表面化学组成进行定性分析。实验结果表明,改性后PBO纤维芯吸高度大幅上升,接触角明显降低,并且在其表面产生明显刻痕,局部有剥离现象,改性后PBO纤维O、N元素含量均有所提高,PBO纤维润湿性明显增强。()     

Effect of side chain on wettability and adhesion performance of acrylic pressure-sensitive adhesives on thin silicon wafer

Acrylic pressure-sensitive adhesives (PSAs) need to show proper adhesion and improved wettability on the silicon wafer as the wafer becomes thinner. The acrylic copolymers were synthesized by solution radical polymerization of 2-ethylhexyl acrylate, ethyl acrylate, and acrylic acid with AIBN as an initiator. Adhesion performance and wettability of acrylic PSAs were studied depending on the content of lauryl side chains and the degree of crosslinking. The introduction of lauryl side chain was characterized by Fourier transform infrared spectroscopy. The adhesion performance of acrylic PSAs having lauryl side chain was investigated using contact angle, wettability, probe tack, peel strength, and cohesiveness tests. The wettability of acrylic PSAs was improved significantly with increasing the content of lauryl side chain.     

Evaluation of fiber wettability based on an immerging force measurement

This article provides a new approach to estimate the wettability of fibers based on the force analysis in immerging procedure. A fiber in horizontal is forced into and withdrawn from the liquid at a certain speed, and the force changes are detected simultaneously. The experimental results show that the force impulse can be found at fiber contacting with liquid and immersed into liquid, and its value depends on the wettability of the fiber. According to the force impulses of different fibers, the immerging behavior of the fibers can be obtained and categorized into four characteristics. Meanwhile, the wettability of the fibers can be evaluated with the wettability factor, w, derived from the fiber immerging curve, where w is the ratio of the force increment on fiber initially contacting with the liquid to the force increment on liquid surface closing with fiber immerging into the liquid, and with the contact angle, θ, calculated from the wettability factor (θ = π/(w+1)) supposed that the fiber is a circular cross section. The pulling‐out test for a fiber has also been conducted and the results are discussed briefly in this article. The force measurement indicates that the method can be used for various fibers with short length, or lower density than that of the liquid, or poor wettability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2659–2666, 2006     

基于光学测量的异形纤维润湿性差异研究

气液聚结过滤在过程工业领域具有广泛应用,纤维材料润湿性是影响聚结元件过滤性能的关键因素。基于光学测量法,本工作开展了单根三角形、三叶形和十字形纤维表面的液体润湿性差异研究,分析了液体接触角及体积的变化过程,考察了液体类型、纤维倾斜角度及异形度对润湿性的影响。结果表明,液体表面张力越小,接触角越小,润湿性越强,但液体的挥发性易导致实际接触角大于理论接触角。三甘醇、癸二酸二辛酯和硅油的接触角基本不随时间发生变化,水和乙醇的接触角随时间逐渐减小且由于乙醇挥发速率较高,导致减小速率更大。液体接触角随异形纤维的倾斜角度呈“V”形分布,即存在极小值点(倾斜角度为30°),使纤维润湿性达到最佳。当纤维异形度增大时,不同液体间的接触角差异缩小、整体润湿性提高,表明在制备预过滤层或排液层材料时,宜选择异形度较高的纤维。     

含氟丙烯酸酯共聚物涂膜表面润湿性的研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸β–羟乙酯(HEMA)、(甲基)丙烯酸高级酯(AAs)、含氟(甲基)丙烯酸酯(Fs)等单体为原料,HDI三聚体为固化剂,通过改变共聚物组成、氟碳链长、(甲基)丙烯酸高级酯烷烃链长等因素,合成了一系列的含氟丙烯酸酯共聚物。采用水、煤油和液压油接触角以及水滴滚动距离,表征了共聚物涂膜的表面润湿性,并探讨了其影响因素。结果表明,共聚物组成和结构、烷烃链长对水的接触角影响不大,而对水的滚动性能具有较大影响;氟碳链长以及氟单体的添加方式对油水接触角和水的滚动性能有较大影响;烷烃侧链的柔顺性对油的接触角影响较大,而对水几乎没有影响。     

Wettability reversal of reservoir rock surface through surfactant stabilized microemulsion

In the process of the tertiary recovery of oil and gas resources, it is necessary to use external fluids to displace the crude oil in the reservoir. Whether the crude oil on the surface of the rock can be effectively displaced and the wettability of the rock can be changed to avoid re-adsorption by the crude oil is directly related to the level of oil recovery. Therefore, it is critical to study the cleaning and wettability reversal of reservoir rock surface. Because microemulsions have outstanding performance in changing the wettability of rocks and solubilizing crude oil, this paper uses cetyl trimethyl ammonium bromide (CTAB) as a surfactant and n-butanol as a co-surfactant to prepare microemulsions. The performance of microemulsions with different microstructures on the cleaning and wettability changes of crude oil on the rock surface were studied. The results show that the water-in-oil (W/O) microemulsion has good cleaning efficiency, and the oil removal rate on the sandstone core surface can reach 79.65%. In terms of changing the wettability of the rock surface, W/O, bi-continuous phase (B.C.) and oil-in-water (O/W) microemulsions can change the core surface from lipophilic to hydrophilic. And the effects of the B.C. and O/W microemulsions are more obvious. The microemulsion system that was prepared based on cationic surfactants has a good application prospect in changing the wettability of the reservoir and cleaning the adsorbed crude oil.     

Characterization of non-uniform wettability on flame-treated polypropylene-film surfaces

The flame treatment of polypropylene (PP) film involves the use of impinging, conical flames to oxidize the surface of the PP.Depending on treatment conditions, the PP film can be exposed to an inhomogeneous environment because of the conical shape of the flames. This environment can lead to cross-web variations, or 'lanes', in the wettability of the film. We have developed a simple method to quantify these non-uniformities using the information provided by the Wilhelmy plate technique of dynamic contact angle measurement. Both surface-averaged and spatially resolved surface-energy data can be obtained by this technique. In the case of our PP film, the spatial nonuniformities were found to be caused by variations in surface chemistry, not topography. These nonuniformities are not observed on untreated PP. Use of this method enables a quantitative evaluation of the effects of flame-treatment process variables on treatment uniformity.     

Line tension and wettability effects on reduced gravity nucleate boiling heat transfer

Line tension has a significant influence on contact angle during boiling at normal gravity, but previous studies conducted at reduced gravity levels have not considered this parameter. Models were developed to study the validity of neglecting line tension and to examine the influence of contact angle on heat transfer in reduced gravity. It was shown that, although line tension may have an effect at normal gravity, line tension effects are insignificant in reduced gravity. A more non-wetting liquid on a solid surface has significantly increased heat transfer from the surface to a bubble due to a larger departure radius.     

The influence of metallic surface wettability on bacterial adhesion

The wettability of AISI 304 stainless steel with 2B and 2RB surface finishes expressed in terms of the solid surface free energy was investigated with respect to the cleaning process. It was shown that cleaning affects the wettability of a solid surface. Depending on the cleaning method, ranged from 43.4 to 277.8 mJ m^-2 for the 2RB surface and from 34.4 to 122.8 mJ m ² for the 2B surface. There was no direct relationship between the number of adhering bacteria and or the wettability of solids. However, it was found that the adhesion of Streptococcus thermophilus was driven by a balance between and The experimental results are as expected based on thermodynamic predictions when the spreading pressure is accounted for in the surface free energy of bacteria, determination.     

常压等离子体改善合成纤维吸湿性的研究

用氦气作为等离子体的气体源、对涤纶、锦纶6、高强度聚乙烯纤维,Twaron 1000芳纶4种合成纤维进行常压等离子体处理,改善纤维的吸湿性能。结果表明:常压等离子体处理,对涤纶和锦纶6的表面有一定的刻蚀作用,但对高强度聚乙烯纤维、Twaron 1000芳纶的表面没有明显影响;经常压等离子体处理后,合成纤维表面氧、氮有所增加,吸湿性能得到提高,强度没有显著变化。     

Factors affecting the wettability of polymer surfaces

The inconsistencies in contact angle data presented in the literature can be attributed to a number of factors. The awareness of these factors would allow novice researchers to make meaningful contact angle measurements and interpretations. In this survey the effects of surface roughness and heterogeneity, surface preparation and the presence of contaminants, the vapor environment, pressure and temperature, drop size, electrical charge, and heat transfer on the wettability of polymer surfaces were examined.     

Contact angle and wettability of hybrid surface-treated metal adherends

Adhesion performance of adhesively bonded metal joints with aluminum and stainless steel was much dependent on the surface treatment of the adherends. This work was aimed at optimizing hybrid surface treatments to improve wettability of metal surfaces and strength of adhesive metal joints, which was a combination of mechanical, chemical, and energetic surface treatment methods. The surface free energies and wettability of hybrid surface-treated metal adherends were measured for different treatment conditions with abrasion, grit blast, sulfuric acid etching, phosphoric acid anodizing, silane treatment, plasma treatment, and flame treatment. The surface morphology and chemical composition of the metal adherends were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy and the bond strengths of the single-lap joints composed of aluminum and stainless steel adherends were measured with respect to hybrid surface treatment conditions. From the experiments, an effective hybrid surface treatment condition was suggested for metal surfaces with super-hydrophilic characteristics. Also, the failure mode of adhesive metal joints was evaluated by photo-surface analysis method.     

Comparative clinical wettability of teeth and intraoral mucosa

The observed reduced adhesiveness of human intraoral mucosa, as compared with adjacent teeth, was determined for 14 healthy humans to correlate with differing measured intraoral contact angles for a variety of otherwise non-interacting test liquids on these two equally water-wettable surfaces under clinical conditions. Measurements were made on the front maxillary tooth surfaces and the-inner lower lip mucosal surfaces of the same subjects, either immediately upon first exposure of the oral tissues or after 30-60 s drying in ambient air. Lower critical surface tensions were found for wet mucosal surfaces (25.4 mN/m) than for wet tooth surfaces (31.2 mN/m). Exposure to air for up to 1 min increased the mucosal critical surface tensions by only 2 mN/m, and had even less influence on the measured properties of tooth surfaces. These data suggest that the observed 'bioabhesive' surface quality of oral mucosa, retaining negligible plaque, is associated with its critical surface tension in the zone near 25 mN/m, as found earlier for the natural fouling-resistant surfaces of dolphins and killer whales.     

液体成型用环氧树脂体系与碳纤维表面浸润性能研究

采用1,4-丁二醇二缩水甘油醚(BDDGE)、聚乙二醇二缩水甘油醚(PEGDGE)、双酚A聚氧乙烯醚06(BPE-06)3种活性环氧树脂稀释剂,分别制备了低黏度适合复合材料液体成型工艺(LCM)的环氧树脂体系,研究了体系与国产碳纤维(HF10)的表面浸润性。首先,研究了稀释剂结构、用量对环氧树脂体系与碳纤维湿润性的影响;其次,研究了稀释剂/树脂/固化剂体系的湿润温度、反应程度对树脂与碳纤维表面的浸润性影响。采用DCAT21表面/界面张力仪分析了树脂与碳纤维界面的前进接触角;采用Young-Dupre法,计算了树脂与碳纤维的热力学粘附功。结果表明,采用稀释剂降低黏度,可以有效改善树脂体系与碳纤维的浸润性;相同黏度时,不同结构稀释剂提高浸润性效果顺序为:PEGDGEBPE-06BDDGE;升高温度可以提高环氧树脂与碳纤维的浸润性;随着反应程度的提高,树脂体系与碳纤维的湿润性变好。     

Effects of surface flaws on the wettability of solids

Wetting hysteresis, or the variability of contact angle, is recognized to be caused by several phenomena. In particular, we consider it to be due to heterogeneity of the solid surface in contact with the liquid. Results describing the deformation of an initially straight triple line in the proximity of an isolated, small, energetic inhomogeneity are summarized. The theory is extended to describe the behaviour of a wetting front near a circular, high-energy (i.e. corresponding to zero intrinsic contact angle) flaw of dimensions comparable to those of the triple line distortion. A simple model is proposed to explain the breakaway of the isthmus of liquid connecting the flaw to the bulk liquid. Separation time is found to be proportional to ^-5, where 0 is the intrinsic contact angle of the solid/ liquid system. The behaviour of a triple line on a solid possessing a randomly distributed population of identical, small, circular flaws is considered. Contact angle hysteresis can thus be explained, as can the noise often observed in a (dynamic) Wilhelmy plate experiment. A simple statistical model is proposed in which random force fluctuations related to a moving triple line are shown to correspond to the Poisson process of probability theory.