皮革园区废水集中治理方案

论述了皮革园区皮革废水的性质,根据制革行业污水的特点提出并论述了污水采用“五水分流分治、企业厂内治理与集控区综合治理相结合的治污模式”的处理要求及其达标保证措施.     

钢材表面处理工艺对环氧涂层附着力的影响

海洋工程涂层保护性能的强弱与涂装作业前钢材表面处理质量的好坏有直接关系。基于此,寻找那些可以使钢材表面获得高附着力的表面处理工艺是相当有必要的。环氧涂层为本文的实验对象,通过试验数据分析钢材表面采用的不同喷砂工艺和粗糙度的关系,继而进一步分析粗糙度的变化对环氧涂层附着力变化的影响。     

表面处理剂对隔热层粘接性能的研制

为提高隔热层粘接强度,采用材料拉伸强度测试方法,研究了空气湿度、处理剂浓度对常温固化磷酸盐胶黏剂粘接隔热层力学性能的影响.研究表明.当处理剂浓度为5%,空气湿度为70%.处理剂处理的隔热层可以在20～1200℃达到隔热层深层破坏,而且粘接强度还得到较大提高,表明该处理剂可以显著提高隔热层的粘接强度.     

Surface Roughness on Adhesion of Silver Colloids to a Polyimide Substrate

The adhesion of silver colloids to a polyimide (PI) substrate was investigated in this study. This issue would be of concern when one tried to print electronic circuits on a flexible PI substrate. To enhance the adhesion between them, the PI surface was first roughened by using the sandblasting technique, and varying degrees of roughness were achieved using various sizes of alumina particles and various air pressures for sandblasting. The adhesion strength of silver colloids to the PI substrate after sintering was then measured according to both ASTM D4541 and ASTM 3359 standards. The results indicated that adhesion strength increased proportionally with surface roughness; however, this enhancement effect was lessened when the roughness was above 880 nm. Sintering temperature was also beneficial in increasing adhesion to the substrate; however, the electrical resistance of the silver colloids after sintering also increased with the degree of roughness. This implied that the packing of silver colloids was also affected by surface roughness. Consequently, values of surface roughness were optimal when adhesion strength and electrical resistivity were balanced.     

Treatment of Leather Plant Effluent by Membrane Separation Processes

Abstract

A scheme is proposed for the treatment of the leather plant effluent using membrane based separation processes. The effluent coming out from the various upstream units of the leather plant (except chrome tanning) are combined and a two step pressure driven membrane processes involving nanofiltration (NF) and reverse osmosis (RO) are adopted after a pretreatment consisting of gravity settling, coagulation, and cloth filtration. The entire membrane separation scheme is validated by conducting experiments under a continuous cross flow mode. A detailed parametric study for cross flow experiments is investigated to observe the effects of the operating conditions, i.e., the transmembrane pressure drop and the cross flow velocity on the permeate flux and quality for both NF and RO. Using a combination of osmotic pressure and solution diffusion model for both NF and RO, the effective osmotic pressure coefficient, solute diffusivity, and the solute permeability through the membrane are obtained by optimizing the experimental permeate flux and concentration (in terms of total dissolved solids) values for this complex industrial effluent. The BOD and COD values of the finally treated effluent are well within the permissible limits (in India).     

面向社会和行业急需进行合成革专业方向的建设

本文分析了合成革行业的发展现状和社会对合成革专业人才的需求现状,从合成革专业方向建设的角度,提出了具体的解决方案,并且介绍了我校合成革专业方向的课程体系设置,以期更好地培养出满足社会需求的专业人才。     

A comparative study on the use of photoreagents for the enhancement of adhesion on heavy-duty leather (Salz leather)

This paper aims to expand on work presented by us in previous publications regarding the enhancement of adhesion on leather substrates with photoreagent type primers. Two new reagents were synthesized: 3,5-dihydroxyphenyl-4-azidobenzoate (7) and 4,4′-ethylene-1,1′-diphenyl azide (8) and used as an intimate mixture with commercial polyurethane adhesive (Solibond PU39), to enhance the adhesion of Salz leather surfaces. The molecular design of the primer molecule was intended to provide 2- and 3-point fixation between the substrate and adhesive.

The strength of adhesive joints do not seem to be highly dependent on the molecular structure of the primers investigated in respect to the type of OH groups present (aliphatic or aromatic), both confer high adhesive strengths under dry and wet testing conditions. Cyanuric chloride (CNCl)₃ a commercially used primer when tested under the same conditions for comparison purposes, gave good results but with a high standard deviation.

Overall, the azide primers generate good, reliable joint strengths under extreme testing conditions and we believe they present negligible technological problems to industrial scale implementation.     

How Compliance Compensates for Surface Roughness in Fibrillar Adhesion

Fibrillar interfaces play an important role in the ability of many small animals to adhere to surfaces. Surface roughness is generally deleterious to adhesion because it hinders the ability of mating surfaces to make contact, but fibrillar surfaces compensate for surface roughness by virtue of their enhanced compliance. We examine the relationship between roughness and compliance by analyzing the mechanics of detaching an array of fibrils from a substrate. The theory of Johnson, Kendall, and Roberts is used to describe the interfacial adhesion of each fibril, and roughness is modeled by making the fibril length a random variable subject to a probability distribution. We solve for the mean force response of a fibrillar array as a function of the displacement of the entire array. From these results we extract the mean fibrillar pull-off force and work to separate the fibrillar array and substrate. We show how the mean fibrillar pull-off force decreases with increasing roughness-height standard deviation: the relationship is linear for small height standard deviation, and the pull-off force trails off to zero for very rough surfaces. Conversely, the work of separation is shown to be unaffected by small roughness-height standard deviation, although it decreases toward zero for rougher surfaces. The effects of roughness may be offset by increasing fibrillar compliance; for small roughness-height standard deviation, we show that the reduction in pull-off force is inversely proportional to the normalized compliance. We also show that the work of separation increases linearly with the compliance when the compliance is large compared with the roughness-height standard deviation.     

How Compliance Compensates for Surface Roughness in Fibrillar Adhesion

Fibrillar interfaces play an important role in the ability of many small animals to adhere to surfaces. Surface roughness is generally deleterious to adhesion because it hinders the ability of mating surfaces to make contact, but fibrillar surfaces compensate for surface roughness by virtue of their enhanced compliance. We examine the relationship between roughness and compliance by analyzing the mechanics of detaching an array of fibrils from a substrate. The theory of Johnson, Kendall, and Roberts is used to describe the interfacial adhesion of each fibril, and roughness is modeled by making the fibril length a random variable subject to a probability distribution. We solve for the mean force response of a fibrillar array as a function of the displacement of the entire array. From these results we extract the mean fibrillar pull-off force and work to separate the fibrillar array and substrate. We show how the mean fibrillar pull-off force decreases with increasing roughness-height standard deviation: the relationship is linear for small height standard deviation, and the pull-off force trails off to zero for very rough surfaces. Conversely, the work of separation is shown to be unaffected by small roughness-height standard deviation, although it decreases toward zero for rougher surfaces. The effects of roughness may be offset by increasing fibrillar compliance; for small roughness-height standard deviation, we show that the reduction in pull-off force is inversely proportional to the normalized compliance. We also show that the work of separation increases linearly with the compliance when the compliance is large compared with the roughness-height standard deviation.     

提高PUF表面涂层附着力的几种方法

采用了几种不同的表面处理方法,溶剂擦拭法、不饱和聚酯原子灰裱糊改性法、Ar~+直流等离子体表面轰击改性法以及Ar/O_2射频等离子体表面轰击改性法等, 提高了聚氨酯泡沫塑料(PUF)与聚酯涂层的附着力。而原子灰腻子表面改性具有简单易行和适用性较好,射频Ar/O_2等离子体表面改性尽管依赖于专用的设备,但具有最好的效果。     

表面处理对剑麻纤维表面状况及热性能的影响

采用含氟防水剂和硅烷偶联剂对剑麻纤维进行表面处理。通过扫描电镜(SEM)、热重分析(TG)、红外光谱(IR)、X-射线光电子能谱(XPS)和表面张力试验等手段表征了处理前后的剑麻纤维表面状况和热性能的变化。结果表明．防水剂与剑麻纤维的作用主要以化学作用为主,并使得剑麻纤维束的结合力减弱,但是防水剂能有效地降低剑麻纤维的吸水性。KH-550与剑麻纤维的作用主要以物理作用为主,并使得剑麻纤维束结合得更紧。     

Surface Activation and Adhesion Properties of Wood-Fiber Reinforced Thermoplastic Composites

Four surface activation methods were evaluated on a series of wood-fiber reinforced thermoplastic composites (WPCs) as a means to improve the adhesion of a water-based acrylic coating. Treatments with chromic acid and oxygen plasma performed best, increasing the acrylic coating peel load to WPCs by 170 and 122%, respectively, and yielding adhesion levels equivalent to or higher than those obtained on wood. The benzophenone/ultraviolet and flame treatments also improved the coating adhesion by 100 and 64%, respectively, but did not reach the adhesion levels achieved on wood. For both the chromic acid and oxygen plasma treatments, the WPC formulation impacted the treatment efficacy. Profilometry and scanning electron microscopy (SEM) showed that the chromic acid treatment acted mainly by roughening WPC surfaces. While surface oxidation was not evident from attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), the improved wettability of WPCs with water suggested that the oxygen plasma treatment oxidized WPCs.     

Surface Activation and Adhesion Properties of Wood-Fiber Reinforced Thermoplastic Composites

Four surface activation methods were evaluated on a series of wood-fiber reinforced thermoplastic composites (WPCs) as a means to improve the adhesion of a water-based acrylic coating. Treatments with chromic acid and oxygen plasma performed best, increasing the acrylic coating peel load to WPCs by 170 and 122%, respectively, and yielding adhesion levels equivalent to or higher than those obtained on wood. The benzophenone/ultraviolet and flame treatments also improved the coating adhesion by 100 and 64%, respectively, but did not reach the adhesion levels achieved on wood. For both the chromic acid and oxygen plasma treatments, the WPC formulation impacted the treatment efficacy. Profilometry and scanning electron microscopy (SEM) showed that the chromic acid treatment acted mainly by roughening WPC surfaces. While surface oxidation was not evident from attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), the improved wettability of WPCs with water suggested that the oxygen plasma treatment oxidized WPCs.     

制鞋材料的表面处理

综述了常用鞋帮鞋底材料的性质,以及如何根据不同材质运用不同方式进行表面处理。     

难粘高分子材料的表面处理技术

本文综述了聚乙烯、聚丙烯、聚四氟乙烯等难粘材料的表面处理技术的发展状况和新进展 。     

Some Contributions of Surface Analysis to the Development of Adhesion Theories

A concise historical account of the development of adhesion theories and a critical discussion of their contemporary relevance are given.

The pioneering work of McBain and Hopkins in 1925 led to the development of the modern adsorption and mechanical theories of adhesion. Somewhat later, there were important contributions from Russia where workers introduced the electrostatic theory (Deryaguin) and the diffusion theory of adhesion (Voyutskii).

Recent developments in contact mechanics, molecular dynamics, and, in particular, surface analysis have provided considerable insight into the nature of the interface and interfacial region in adhesive joints. These suggest that adsorption, mechanical, and even diffusion effects cannot be completely isolated from one another. It is argued that each theory is best regarded as emphasising a different aspect of a more comprehensive model which, in principle, relates molecular dispositions in the region of the interface to macroscopic properties of an adhesive joint.     

Some Contributions of Surface Analysis to the Development of Adhesion Theories

A concise historical account of the development of adhesion theories and a critical discussion of their contemporary relevance are given.

The pioneering work of McBain and Hopkins in 1925 led to the development of the modern adsorption and mechanical theories of adhesion. Somewhat later, there were important contributions from Russia where workers introduced the electrostatic theory (Deryaguin) and the diffusion theory of adhesion (Voyutskii).

Recent developments in contact mechanics, molecular dynamics, and, in particular, surface analysis have provided considerable insight into the nature of the interface and interfacial region in adhesive joints. These suggest that adsorption, mechanical, and even diffusion effects cannot be completely isolated from one another. It is argued that each theory is best regarded as emphasising a different aspect of a more comprehensive model which, in principle, relates molecular dispositions in the region of the interface to macroscopic properties of an adhesive joint.     

无机盐和粉体材料表面处理技术

本文综述无机盐和粉体材料表而处理的机理、方法、处理剂的选择和工业开发与应用。     

基材表面处理对聚氨酯合成革剥离强度的影响

选择不同树脂和用量的硅烷偶联剂KH550对涤纶纤维平纹基材进行表面处理,研究了不同处理工艺对聚氨酯合成革剥离强度的影响。结果表明,对涤纶纤维平纹基材来说,聚氨酯溶液打底胶处理的基材合成革剥离强度更高;随着硅烷偶联剂加入量的提高,合成革剥离强度提高。     

表面处理对NR粘合性能的影响

研究机械打磨、硫酸处理和次氯酸钠处理3种表面处理方法对NR粘合性能的影响.结果表明:经过硫酸适当处理后,NR硫化胶与水的表面接触角明显减小,表面润湿性改善,牯合性能显著提高;硫酸处理NR硫化胶的粘合性能优于机械打磨和次氯酸钠处理的NR硫化胶.