scholarly journals Effects of Surface Energy Reducing Agents on Adhesion Force in Liquid Bridge Microstereolithography

2020 ◽  
Vol 36 ◽  
pp. 101522
Author(s):  
Aslan Alamdari ◽  
Jeongwoo Lee ◽  
Myoeum Kim ◽  
Md. Omar Faruk Emon ◽  
Ali Dhinojwala ◽  
...  
Keyword(s):  
Surface Energy ◽  
Liquid Bridge ◽  
Adhesion Force ◽  
Reducing Agents

scholarly journals Correlation between Surface Energy and Adhesion Force of Polyethylene/Paperboard: A Predictive Tool for Quality Control in Laminated Packaging

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Danielle M. F. Madeira ◽  
Osvaldo Vieira ◽  
Luís Antonio Pinheiro ◽  
Benjamim de Melo Carvalho
Keyword(s):  
Quality Control ◽  
Surface Energy ◽  
Adhesion Force ◽  
Paper Industry ◽  
Peel Test ◽  
Practical Method ◽  
Test Method ◽  
Predictive Tool ◽  
Contact Angle Analysis ◽  
Poor Adhesion

Poor adhesion continues to be a problem for manufacturers of laminated packaging. Therefore, the aim of this research was to study the effect of flame treatment, the type of coating, and starch application on the adhesion force of polyethylene/paperboard. The force of adhesion was determined using the peel test method; the paper surface energy was assessed by contact angle analysis; and paperboard roughness was determined by profilometer. The flame treatment did not affect the surface roughness but significantly increased the paperboard surface energy. The paperboard coated with polar latex showed much higher surface energy than the paperboard coated with nonpolar latex. The adhesion force of polyethylene presented a linear correlation to the surface energy of the paperboard. Therefore, the surface energy of paperboard is an excellent indication of its adhesion force to polyethylene, and this represents a very reliable and practical method in terms of quality control in the paper industry for producing laminated packages.

Adhesion Force Between High Energy Surfaces in Vapor Atmosphere

1994 ◽  
Vol 366 ◽  
Author(s):  
Jerome Crassous ◽  
Jean-Luc Loubet ◽  
Elisabeth Charlaix
Keyword(s):  
Liquid Bridge ◽  
Adhesion Force ◽  
Van Der Waals ◽  
Surface Force ◽  
High Energy ◽  
Attractive Force ◽  
Experimental Measurements ◽  
Metallic Substrates ◽  
Energy Surfaces ◽  
Good Agreement

ABSTRACTWe report experimental measurements of the adhesion force between metallic substrates in undersaturated heptane vapor atmosphere, with a surface force apparatus. The attractive force between the substrates is strongly dependant of the condensation of a liquid bridge connecting the surfaces. The results show the importance of wetting phenomena for the maximum attractive force: we find that this maximum attraction varies as the power two-third of the curvature of the meniscus connecting the surfaces, in good agreement with the theory of Van der Waals wetting.

scholarly journals Adhesion of Individual Attachment Setae of the Spider Cupiennius salei to Substrates With Different Roughness and Surface Energy

2021 ◽  
Vol 7 ◽  
Author(s):  
Bastian Poerschke ◽  
Stanislav N. Gorb ◽  
Clemens F. Schaber
Keyword(s):  
Surface Energy ◽  
Glass Substrate ◽  
Adhesion Force ◽  
Adhesive System ◽  
Adhesive Contact ◽  
Contact Angles ◽  
Individual Variability ◽  
Van Der Waals Interactions ◽  
Smooth Surfaces ◽  
Cupiennius Salei

Dynamic adhesion is a key ability for animals to climb smooth surfaces. Spiders evolved, convergent to geckos, a dry adhesive system made of setae branching into smaller microtrichia ending as spatulae. Several previous studies concentrated either on the whole adhesive claw tuft on the spider´s foot that consists of attachment setae or on the single adhesive contact elements, the microtrichia with spatula-shaped tips. Here, the adhesion of single setae of the spider Cupiennius salei was examined and the morphology of the pretarsus and the fine structure of the setae were studied in further detail. Using individual setae fixed to force sensing cantilevers, their adhesion at different contact angles with a glass substrate was measured as well as their adhesive performance on substrates with different roughness and on smooth surfaces with different surface energies. The results show an individual variability of the adhesive forces corresponding to the seta morphology and especially to the seta tip shape. The tip shapes of the setae vary largely even in neighboring setae of the pretarsal claw tuft that comprises approximately 2,400 setae. Regarding surface energy of the substrate, the adhesion force on hydrophobic polytetrafluoroethylene was 30% of that on a hydrophilic glass substrate, which points to the importance of both van der Waals interactions and hydrogen bonds in spider adhesion.

Effect of Polymer Substrates on Nano Scale Hot Embossing

2003 ◽  
Vol 782 ◽  
Author(s):  
Jin-Hyung Lee ◽  
Hyun-Woo Lim ◽  
Jin-Goo Park ◽  
Eun-Kyu Lee ◽  
Yangsun Kim
Keyword(s):  
Surface Energy ◽  
Surface Properties ◽  
Process Development ◽  
Adhesion Force ◽  
Polymer Surface ◽  
Hot Embossing ◽  
Surface Characteristic ◽  
Direct Writing ◽  
Polymer Substrates ◽  
Nano Size

ABSTRACTHot embossing has been widely accepted as an alternative to photolithography in generating patterns on polymer substrates. The optimization of embossing process should be accomplished based on polymer surface properties. Therefore, in this paper, polymers with different surface characteristic were selected and the surface properties of each polymers such as surface energy and adhesion force were investigated by contact angle and AFM. Based on these results, the imprinted nano patterns were compared. Silicon molds with nano size patterns were fabricated by e-beam direct writing. Molds were coated with self-assembled monolayer (SAM) of (1, 1, 2, 2H –perfluorooctyl)-trichlorosilane to reduce the stiction between molds and polymer substrates. For embossing, pressure of 500 psi, embossing time of 5 min and temperature of above transition temperature were applied. Mr-I 8010 polymer (Micro Resist Technology), Polymethylmethacrylate (PMMA 495k) and LOR (polyaliphatic imide copolymer) were used as substrate for hot embossing process development in nano size. These polymers were spun coated on the Si wafer with the thickness of 150 nm. The nano size patterns obtained by hot embossing were identified by atomic force microscopy without breaking the pattern and compared based on the polymer surface properties. The mr-I 8010 which has the lowest surface energy and adhesion force shows the best demolding property.

The Effects of Surface Energy and Roughness on Adhesion Force

2006 ◽  
Vol 30 (11) ◽  
pp. 1335-1347 ◽  
Author(s):  
Jong-Joo Rha ◽  
Sik-Cheol Kwon ◽  
Yong-Soo Jeong
Keyword(s):  
Surface Energy ◽  
Adhesion Force

scholarly journals Laser-Induced Periodic Surface Structuring of Poly(trimethylene terephthalate) Films Containing Tungsten Disulfide Nanotubes

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1090 ◽  
Author(s):  
Javier Prada-Rodrigo ◽  
René I. Rodríguez-Beltrán ◽  
Sandra Paszkiewicz ◽  
Anna Szymczyk ◽  
Tiberio A. Ezquerra ◽  
...  
Keyword(s):  
Surface Energy ◽  
Young’S Modulus ◽  
Adhesion Force ◽  
Young's Modulus ◽  
Femtosecond Laser Pulses ◽  
Tungsten Disulfide ◽  
Heat Diffusion ◽  
Polar Component ◽  
Periodic Surface ◽  
Trimethylene Terephthalate

We report the study of the formation of Laser Induced Periodic Surface Structures (LIPSS), with UV femtosecond laser pulses (λ = 265 nm), in free-standing films of both Poly(trimethylene terephthalate) (PTT) and the composite PTT/tungsten disulfide inorganic nanotubes (PTT-WS2). We characterized the range of fluences and number of pulses necessary to induce LIPSS formation and measured the topography of the samples by Atomic Force Microscopy, the change in surface energy and contact angle using the sessile drop technique, and the modification in both Young’s modulus and adhesion force values with Peak Force-Quantitative Nanomechanical Mapping. LIPSS appeared parallel to the laser polarization with a period close to its wavelength in a narrow fluence and number of pulses regime, with PTT-WS2 needing slightly larger fluence than raw PTT due to its higher crystallinity and heat diffusion. Little change was found in the total surface energy of the samples, but there was a radical increase in the negative polar component (γ−). Besides, we measured small variations in the samples Young’s modulus after LIPSS formation whereas adhesion is reduced by a factor of four. This reduction, as well as the increase in γ−, is a result of the modification of the surface chemistry, in particular a slight oxidation, during irradiation.

scholarly journals van der Waals forces influencing adhesion of cells

2015 ◽  
Vol 370 (1661) ◽  
pp. 20140078 ◽  
Author(s):  
K. Kendall ◽  
A. D. Roberts
Keyword(s):  
Cell Adhesion ◽  
Surface Energy ◽  
Adhesion Molecules ◽  
Adhesion Force ◽  
Van Der Waals ◽  
Van Der Waals Forces ◽  
Surface Molecules ◽  
Molecular Adhesion ◽  
Surface Active ◽  
Water Cut

Adhesion molecules, often thought to be acting by a ‘lock and key’ mechanism, have been thought to control the adhesion of cells. While there is no doubt that a coating of adhesion molecules such as fibronectin on a surface affects cell adhesion, this paper aims to show that such surface contamination is only one factor in the equation. Starting from the baseline idea that van der Waals force is a ubiquitous attraction between all molecules, and thereby must contribute to cell adhesion, it is clear that effects from geometry, elasticity and surface molecules must all add on to the basic cell attractive force. These effects of geometry, elasticity and surface molecules are analysed. The adhesion force measured between macroscopic polymer spheres was found to be strongest when the surfaces were absolutely smooth and clean, with no projecting protruberances. Values of the measured surface energy were then about 35 mJ m −2 , as expected for van der Waals attractions between the non-polar molecules. Surface projections such as abrasion roughness or dust reduced the molecular adhesion substantially. Water cut the measured surface energy to 3.4 mJ m −2 . Surface active molecules lowered the adhesion still further to less than 0.3 mJ m −2 . These observations do not support the lock and key concept.

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