稻草刨花板基材表面润湿性能的研究

通过实验,对稻草刨花板表面自由能以及不同配比的脲醛树脂(UF)和异氰酸酯(MDI)混合胶液对稻草刨花板表面的润湿性能进行了测量和分析。试验结果表明,稻草刨花板的表面自由能高于稻草原料,不同配比的UF和MDI混合胶液在稻草刨花板表面的接触角是随着时间的延长而减小最后逐渐趋于稳定。     

低温氩等离子体表面改性提高PET亲水性

为了提高PET材料表面的亲水性,应用低温氩等离子体对PET进行表面处理。对不同等离子体处理工作参数(放电功率、放电时间、工作气压)下PET薄膜表面的水接触角变化进行了规律性和原理分析。用IR和SEM分析了处理前后PET薄膜表面形态的变化。实验结果表明:不同等离子体处理工作参数下PET薄膜表面的水接触角的变化呈现不同的规律性;经等离子体处理后PET薄膜表面CO和CC键的数量增加,酯基数量减少,显著提高了薄膜的亲水性;但是低温氩等离子体处理后的PET薄膜放置一段时间后时效性问题比较明显。     

低密度聚乙烯的毛细管流变性能

为研制低密度聚乙烯(LDPE)纤维,确定合理的纺丝工艺参数,利用毛细管流变仪研究LDPE材料的流变性能.研究结果表明:LDPE剪切黏度随剪切速率的增大而降低,随温度的升高而降低,非牛顿指数n小于1,随温度的升高而变大;当LDPE纺丝在加工温度为205℃时,非牛顿指数n为0.498,最接近牛顿流体.在150～250℃温度范围内,LDPE的黏流活化能在10 ～13 J/mol之间,且黏流活化能随剪切速率增加而降低,稠度系数K随温度升高而降低,属于假塑性流体,在纺丝过程中可以通过调节温度和剪切速率来改变LDPE熔体的可纺性.     

两种秸秆表面润湿性研究

研究测定了异氰酸酯、脲醛树脂和酚醛树脂胶粘剂对高粱秆与玉米秆表面的接触角,并通过测量不同表面张力的液体对秸秆表面的接触角,推算出秸杆表面的自由能.结果表明:秸秆的表面自由能比木材要低得多,属于低能表面固体.     

YEAST FLOCCULATION: A NEW METHOD FOR CHARACTERISING CELL SURFACE INTERACTIONS

Flocculation is a property of yeast cells that has been traditionally used in industrial fermentations, especially in the brewing and wine industries. It is a cell wall interaction and an increase in flocculation is strongly correlated with an increase in cell surface hydrophobicity . Methods to assay yeast cell surface hydrophobicity are only qualitative and while electrostatic interactions can play an important role, they are not always taken into account . In this work, a simple and accurate method based on contact angle measurements is described to determine yeast cell surface hydrophobicity. With this method, it is possible to quantify yeast cell surface hydrophobicity by determining the free energy of interaction between cells and water molecules. Several yeast strains with different flocculation characteristics have been used to validate the method .     

用矿物质去除脱墨浆中微细胶粘物的可行性

介绍了测定接触角的薄层吸液技术及应用接触角计算表面张力及Gibbs自由能变化的公式.最后以Gibbs自由能变化来判断某种矿物质对某些胶粘物有无粘附作用,从而选择何种矿物质可解决微细胶粘物的沉积问题.     

Method For Studying Surface Topography and Roughness of Onion and Garlic Skins For Coating Purposes

Surface topography and roughness of garlic and onion skins were studied by atomic force microscopy in order to estimate the surface area. Image-processing and Arc/Info software were used to interpret the data. The calculated ratio between apparent and measured surfaces (roughness factor) deviated from 1.11 to 1.15 for untreated and chloroform-treated onion skin, respectively. For garlic, higher values were detected for the untreated skin. The higher the roughness factor, when the coating solutions are easily spread on the fruit or vegetable surfaces, the better the adhesion between coating and skin. A knowledge of true surface areas can help to better estimate required coating-solution volumes.     

硬质合金表面粗糙度对金刚石涂层附着力影响的研究

采用不同粒度的金剐石粉研磨硬质合金基体表面,然后采用酸碱两步法处理基体,清洗后利用热丝化学气相沉积法（HFCVD）沉积金刚石涂层。扫描电镜观察表面金刚石形貌,洛氏硬度压痕法评价涂层结合情况。实验结果表明适当的表面粗糙度可以有效地提高膜基结合水平。     

烟用商标纸与胶黏剂的相互作用及其对粘合强度影响

对典型烟用商标纸和包装胶性能进行分析,研究了胶黏剂在商标纸粘合部位表面液滴的接触角和宽度的变化,探讨了上胶开放时间对商标纸­包装胶组合粘合强度的影响。结果表明,包装胶滴加到商标纸表面上时,无论印刷面还是非印刷面,随着时间的延长,接触角不断减小,液滴宽度不断增加,液滴接触角和宽度达到平稳的时间不同,液滴接触角的降低是扩展和渗透共同作用的结果,而液滴宽度变化只和扩展有关。不同的商标纸-包装胶组合,液滴接触角和宽度的变化不同,上胶开放时间窗口也不同,与胶黏剂的黏度和固含量及商标纸的扩展和渗透性有一定的联系。水对商标纸的润湿性与胶黏剂明显不同,不宜采用水在纸张表面的润湿性来判断胶黏剂的行为。     

卷烟接装胶的吸收性及对粘合性能的影响

本研究在对比分析接装胶性能基础上,通过动态接触角法、动态渗透法、斜面滚球法和90°剥离强度实验法等,对接装胶在接装纸表面的吸收性、渗透性、初粘性和粘合强度进行了研究。结果表明,接装胶在接装纸非印刷面的接触角随时间的变化及动态渗透情况与水不同,高黏度接装胶在多孔性接装纸非印刷面的吸收速率低,高固含量接装胶的动态渗透特征参数t_max和t₉₅小。上胶开放时间对接装胶的初粘性和最终粘合强度均有影响,随着上胶开放时间延长,因接装纸表面对接装胶的吸收,初粘性呈现先上升后下降的趋势,即存在一个最大初粘性的开放时间窗口,低于该时间点封合,不会影响粘合强度,但高于该时间点封合,可能会发生粘合不良问题。     

透气拒水非织造复合材料的研究

本文基于表面能原理对材料的拒水性能作了分析 ,并研究了经过整理的非织造复合材料的性能 ,结果证明该整理工艺是可行的 ,能起到改善非织造复合材料透气性的作用。     

圆柱形衬底金刚石涂层的制备与表征研究

采用偏压增强热丝化学气相沉积法（BE—HFCVD）,以WC—Co硬质合金圆柱体为衬底沉积金刚石薄膜。研究了提高金刚石薄膜形核密度和涂层附着力的新型复合衬底预处理方法,研究结果表明。采用新型复合衬底预处理工艺后,衬底表面凸凹不平,粗糙度达到366nm,相比未采用预处理工艺的表面粗糙度94．5nm,可以大大提高金刚石形核密度,并且处理后钻的成分含量从6％减低到0．4％,在很大程度上提高了金刚石涂层与衬底之间的附着强度。研究结果还表明制备的金刚石涂层均匀且具有较好的表面质量。     

涤纶纤维表面复合改性对其亲水性的影响

为了改善涤纶纤维分子缺乏亲水基团亲水性能差的问题,文章采用等离子体和硅烷偶联剂对其进行复合改性,并对涤纶试样的表面微观形貌、表面接触角、质量变化、单丝强度、官能团等进行测试和分析。结果表明:等离子体处理可以显著改善涤纶的表面亲水性,表面接触角相比无处理之前降低58.5°,但在存放过程中涤纶纤维表面的极性基团变少,表面接触角逐渐增大;经等离子体和硅烷偶联剂复合改性后,表面接触角降低46.3°,维持在85.7°左右。这些改性方式均使涤纶表面亲和作用提升,浸润性得到改善,同时对涤纶纤维质量和单丝强度的影响都很小。     

超疏水导电聚酯织物的制备及其性能

为使织物兼具疏水与导电的性能,使用自制碳黑杂化同质聚酯浆料,先对聚酯织物进行导电整理,再采用溶剂诱导结晶（SINC）的方法在导电织物的表面构造微观粗糙结构,然后用甲基三氯硅烷（MTS）修饰,制备出耐水洗超疏水导电聚酯织物。研究了浆料中聚酯、碳黑的含量以及溶剂诱导结晶处理条件对织物导电及疏水性能的影响,借助场发射扫描电子显微镜、差式扫描量热仪、X射线衍射仪、接触角测量仪等对织物导电、润湿性能、耐用性及表面结构的微观形貌与结晶特点进行表征。结果表明,制备的疏水导电聚酯织物表面电阻率数量级在10 ²～10^３Ω,与水的接触角大于150°,超声水洗12 h后织物表面电阻率数量级不变,与水的接触角不小于140°。     

防水涂布纸涂料配方及防水性能的研究

选取三种典型涂料用抗水剂,通过分析涂布后纸页的Cobb值、静态接触角、油墨吸收性能、拉毛速度等重要指标,研究了防水涂布纸涂料配方及纸张表面防水性能。确定最佳涂料配方。研究表明：底涂配方采用^#2抗水剂且用量为0.5份,面涂涂料采用^#1抗水剂且用量为7．5份时涂布纸具有良好的防水效果和表面性能。采用电子探针（EPMA）进行表面结构分析表明添加^#1抗水剂在涂层表面形成了结构致密的防水涂层。     

Surface modification of nylon fabric and its optimization for improved adhesion in rubber composites

Nylon-6,6 fabric was treated with formic acid for surface roughening and was subjected to Resorcinol Formaldehyde Latex treatment for making rubber composites. Physicochemical effects of surface roughening of nylon were evidenced using scanning electron microscope (SEM), Fourier Transform Infrared spectroscope (FTIR) and differential scanning calorimeter (DSC). Further, the treatment effect on interfacial adhesion was quantified through peel strength test. The process parameters of the formic acid treatment were optimized using Box-Behnken method through geometrical surface roughness obtained through Kawabata evaluation system for micro-surface roughness of nylon to ensure good interfacial adhesion with rubber. Surface modification conditions of 11.2% formic acid concentration, 70 °C temperature and 30 min time were found to yield optimum condition at which surface roughness (SMD) was found to be of 20.1 μm. SEM analysis confirmed the presence of heterogeneous appearance like cracks, etches and micro-rough surfaces on the treated Nylon-6,6 fibre surface. FTIR analysis showed changes in –C = O stretching and –N–H stretching. No significant change was noted in the DSC curve. The peel strength between the rubber and treated fabric was improved to 150% in warp and 124% in weft directions, respectively with reference to the control fabric.     

Importance of surface tension characterization for food, pharmaceutical and packaging products: a review

This article reviews the various theoretical approaches that have been developed for determination of the surface tension of solids, and the applications to food industrial products. The surface tension of a solid is a characteristic of surface properties and interfacial interactions such as adsorption, wetting or adhesion. The knowledge of surface tension is thus of great interest for every domain involved in understanding these mechanisms, which recover a lot of industrial investigations. Indeed, it is the case for the packaging industry, the food materials science, the biomedical applications and the pharmaceutical products, cleaning, adhesive technology, painting, coating and more generally all fields in relation with wettability of their systems. There is however no direct method for measurements of surface tension of solids, except the contact angle measurements combined with an appropriate theoretical approach are indirect methods for estimation of surface tension of solids. Moreover, since the publication by Young (1805) who developed the basis of the theory of contact angle some two hundred years ago, measurements and interpretations are still discussed in scientific literature, pointing out the need to better understand the fundamental mechanisms of solid-liquid interfacial interactions. Applications of surface tension characterization in the field of food materials science are detailed, especially for packaging and coating applications, which recover different actual orientations in order to improve process and quality.     

低温等离子体处理对PET膜性能的影响

选用低温等离子体处理对PET膜进行表面改性.通过扫描电镜、XPS、表面接触角以及表面自由能分析,测试表征了等离子体处理前后膜表面物理形貌结构、化学组分构成以及表面性能的变化情况.研究结果表明,等离子体处理对PET膜产生刻蚀作用,等离子体处理后的样品表面氧/碳、氮/碳含量比有所增加,膜表含氧极性基团如C—O/C—N、C O、C O—O等的含量增加,膜表亲水性有明显改善,表面自由能明显提高.     

硅酸钠表面施胶改善纸张防水性能的机理探讨

分别利用硅酸钠、硅酸钠与淀粉复配进行纸张表面施胶,表面施胶体系中有机硅油用量控制为3%(相对于硅酸钠绝干质量);探讨了施胶量和施胶体系对纸张孔隙率、纸张平均孔径、表面平滑度、Cobb₃₀值和表面接触角的影响;依据毛细管现象公式,探讨及分析了表面施胶纸张的防水机理;利用扫描电镜(SEM)观察分析了表面施胶纸张的表面形貌。结果表明,硅酸钠-淀粉复配体系中,淀粉最佳用量为33%;随着表面施胶体系施胶量的增加,表面施胶纸张的孔隙率和平均孔径均下降;经硅酸钠和硅酸钠-淀粉复配表面施胶后,纸张的表面接触角较原纸大幅提高且硅酸钠-淀粉复配体系对纸张抗水性的改善效果优于硅酸钠。此外,研究还发现,纸张平均孔径的降低、表面接触角的增加及胶层在纸张表面的覆盖是硅酸盐及其复配体系表面施胶纸张产生抗水性的主要原因。     

《家具表面软/硬质覆面材料剥离强度的测定》行业标准解读

随着科学技术的发展,应用于家具及其他木制品表面的覆面材料种类越来越多,要求越来越高。而行业标准QB/T 3655-1999《家具表面软质覆面材料剥离强度的测定》和QB/T 3656-1999《家具表面硬质覆面材料剥离强度的测定》是于1999年发布实施至今,其适用范围、有些技术要求已不能满足行业需要。为此,对这两个行业标准的修订过程和新近发布实施的QB/T 4448-2013《家具表面软质覆面材料剥离强度的测定》和QB/T 4449-2013《家具表面硬质覆面材料剥离强度的测定》标准的主要技术内容进行了解读,并就如何正确认识和使用这两项新标准提出了建议