A new method for quantifying the blocking of coated paperboard

Blocking is undesired adhesion between two surfaces when subjected to pressure and temperature constraints. Blocking between two coated paperboards in contact with each other may be caused by inter-diffusion, adsorption, or electrostatic forces occurring between the respective coating surfaces. These interactions are influenced by factors such as the temperature, pressure, surface roughness, and surface energy. Blocking potentially can be reduced by adjusting these factors, or by using antiblocking additives such as talc, amorphous silica, fatty acid amides, or polymeric waxes. We developed a method of quantifying blocking using a rheometer. Coated surfaces were put in contact with each other with controlled pressure and temperature for a definite period. We then measured the work necessary to pull the two surfaces apart. This was a reproducible way to accurately quantify blocking. The method was applied to determine the effect external factors have on the blocking tendency of coated paperboards, i.e., antiblocking additive concentration, film thickness, temperature, and humidity.

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Paraffin Deposition from Refined Wax-Solvent Systems

Society of Petroleum Engineers Journal ◽

10.2118/2503-pa ◽

1970 ◽

Vol 10 (01) ◽

pp. 17-24 ◽

Cited By ~ 21

Author(s):

Charles C. Patton ◽

Burton M. Casad

Keyword(s):

Molecular Weight ◽

Surface Roughness ◽

Surface Energy ◽

Pipe Wall ◽

Cold Spot ◽

Solution Composition ◽

Solvent Systems ◽

Paraffin Waxes ◽

Deposit Weight ◽

Coated Surfaces

Abstract Paraffin deposition from several relined wax-solvent systems was studied by using a coldspot test apparatus The purpose of the investigation was to determine the effect of surface roughness, plastic coatings and solution composition on the plastic coatings and solution composition on the amount of deposition. No correlation was observed between surface roughness and deposit weight. The wax composition determined whether or not a given deposit remained on a given surface. Normal paraffin waxes of lower molecular weight formed paraffin waxes of lower molecular weight formed deposits that sloughed or slid off smooth steel or plastic coated surfaces and flaked off roughened plastic coated surfaces and flaked off roughened steel or plastic coated surfaces. Wax of a higher molecular weight, containing more microcrystalline material, formed deposits that did not slide or flake off either smooth or roughened steel or plastic coated surfaces. Plastic coatings decreased deposit weights by 30 percent or more for the higher molecular weight wax due to thermal insulation. Deposit weight decreased with stirring rate and increased with time and temperature differential. Introduction Why paraffin adheres to a surface has long been a point of discussion. Two theories that have evolved are summarized as follows. WETTABILITY OR FREE SURFACE ENERGY "As paraffin is deposited on a surface, it is held in place by adsorption forces. These adsorption forces are dependent upon the bee surface energy possessed by both the paraffin and the surface. As possessed by both the paraffin and the surface. As the free surface energy of the plate or surface is reduced, a resultant decrease in the adsorption force holding the paraffin to the plate or surface takes place. This causes a decrease in the amount of paraffin which can be retained on the plate surface for the flow conditions present." SURFACE ROUGHNESS "The results obtained in this investigation indicate that wax does not adhere to the pipe wall but is held in place by surface roughness and/or irregularities. As a wax particle grows along the pipe wall and out into the oil stream, the force pipe wall and out into the oil stream, the force tending to move it out of the tubing would increase. The smoother the surface, the more easily the embryonic deposit would be removed from the surface… Thus, it is concluded that wax does not adhere to steel but that deposits which form on steel surfaces are held in place by surface roughness." Or stated more concisely, "Paraffin deposition on metallic or nonparaffinic plastic surfaces at a given temperature is governed by surface roughness." The purpose of this investigation was to determine the effect of surface roughness, plastic coatings and solution composition on paraffin deposition from refined wax-solvent systems. Transparent refined systems were used so that the process could be studied visually. A cold spot test apparatus similar to that used by Hunt and Jorda was used. EXPERIMENTAL DESCRIPTION OF APPARATUS The deposition tests were carried out and a coldspot tester shown in Fig. 1. This apparatus consists of a double-walled glass test cell, cell lid, cold-spot probe, magnetic stirrer and two constant temperature water circulation systems. The probe face plate temperature was measured throughout each test with a 1/16-in. OD thermocouple that was inserted through the edge of the plate so that the thermocouple bead was positioned at its center. The thermocouple used was a shielded iron-constantan couple with a floating bead. A thermometer was used to measure solution temperature. SPEJ P. 17

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Synthesis, Quantification, and Characterization of Fatty Acid Amides from In Vitro and In Vivo Sources

Molecules ◽

10.3390/molecules26092543 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2543

Author(s):

Ruidong Ni ◽

Suzeeta Bhandari ◽

Perry R. Mitchell ◽

Gabriela Suarez ◽

Neel B. Patel ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Fatty Acid ◽

Apis Mellifera ◽

Chemical Synthesis ◽

Acid Amide ◽

Fatty Acid Amides ◽

Fatty Acid Amide

Fatty acid amides are a diverse family of underappreciated, biologically occurring lipids. Herein, the methods for the chemical synthesis and subsequent characterization of specific members of the fatty acid amide family are described. The synthetically prepared fatty acid amides and those obtained commercially are used as standards for the characterization and quantification of the fatty acid amides produced by biological systems, a fatty acid amidome. The fatty acid amidomes from mouse N18TG2 cells, sheep choroid plexus cells, Drosophila melanogaster, Bombyx mori, Apis mellifera, and Tribolium castaneum are presented.

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GC Analysis of Primary Fatty Acid Amides in Animal Fat

European Journal of Lipid Science and Technology ◽

10.1002/ejlt.202000323 ◽

2021 ◽

pp. 2000323

Author(s):

Milica Jovanovic ◽

Sigurd Schober ◽

Martin Mittelbach

Keyword(s):

Fatty Acid ◽

Gc Analysis ◽

Fatty Acid Amides ◽

Animal Fat

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Effect of Water Temperature, pH Value, and Film Thickness on the Wettability Behaviour of Copper Surfaces Coated with Copper Using EB-PVD Technique

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.60.124 ◽

2019 ◽

Vol 60 ◽

pp. 124-141 ◽

Cited By ~ 1

Author(s):

Naser Ali ◽

Joao Amaral Teixeira ◽

Abdulmajid Addali

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Film Thickness ◽

Water Temperature ◽

Ph Value ◽

Surface Wettability ◽

Copper Surfaces ◽

Force Microscopy ◽

Atomic Force ◽

Static Contact

This research investigates the effect of surface roughness, water temperature, and pH value on the wettability behaviour of copper surfaces. An electron beam physical vapour deposition technique was used to fabricate 25, 50, and 75 nm thin films of copper on the surface of copper substrates. Surface topographical analysis, of the uncoated and coated samples, was performed using an atomic force microscopy device to observe the changes in surface microstructure. A goniometer device was then employed to examine the surface wettability of the samples by obtaining the static contact angle between the liquid and the attached surface using the sessile drops technique. Waters of pH 4, 7, and 9 were employed as the contact angle testing fluids at a set of fixed temperatures that ranged from 20°C to 60°C. It was found that increasing the deposited film thickness reduces the surface roughness of the as-prepared copper surfaces and thus causing the surface wettability to diverge from its initial hydrophobic nature towards the hydrophilic behaviour region. A similar divergence behaviour was seen with the rise in temperature of water of pH 4, and 9. In contrast, the water of pH 7, when tested on the uncoated surface, ceased to reach a contact angle below 90o. It is believed that the observed changes in surface wettability behaviour is directly linked to the liquid temperature, pH value, surface roughness, along with the Hofmeister effect between the water and the surface in contact.

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Rough Air-Soft Elastohydrodynamic Lubrication

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.420.30 ◽

2013 ◽

Vol 420 ◽

pp. 30-35

Author(s):

Khanittha Wongseedakaew ◽

Jesda Panichakorn

Keyword(s):

Surface Roughness ◽

Film Thickness ◽

Modulus Of Elasticity ◽

Contact Region ◽

Elastohydrodynamic Lubrication ◽

Multilevel Methods ◽

Inlet Temperature ◽

Film Pressure ◽

Air Inlet ◽

Air Film

This paper presents the effects of rough surface air-soft elastohydrodynamic lubrication (EHL) of rollers for soft material under the effect of air molecular slip. The time independent modified Reynolds equation and elasticity equation were solved numerically using finite different method, Newton-Raphson method and multigrid multilevel methods were used to obtain the film pressure profiles and film thickness in the contact region. The effects of amplitude of surface roughness, modulus of elasticity and air inlet temperature are examined. The simulation results showed surface roughness has effect on film thickness but it little effect to air film pressure. When the amplitude of surface roughness and modulus of elasticity increased, the air film thickness decreased but air film pressure increased. However, the air inlet temperature increased when the air film thickness increased.

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The Surface-Roughness of Bearing-Surfaces and its Relation to Oil Film Thickness at Breakdown

Proceedings of the Institution of Mechanical Engineers ◽

10.1243/pime_proc_1949_161_011_02 ◽

1949 ◽

Vol 161 (1) ◽

pp. 73-79 ◽

Cited By ~ 8

Author(s):

A. Cameron

Keyword(s):

Surface Roughness ◽

Film Thickness ◽

Hydrodynamic Theory ◽

Quantitative Relation ◽

Metal Contact ◽

Initial Contact ◽

Frictional Drag ◽

Average Roughness ◽

Finished Steel ◽

Oil Film

In this paper the relation of surface roughness of bearing surfaces to allowable film thickness is studied quantitatively with a simple Michell pad apparatus. The pads used were faced with white metal and ran against mild steel collars. The lubricants studied were water, soap solution, paraffin, and light oil. There was little difference in the frictional behaviour of any of the lubricants, except that the aqueous lubricants would not run with very finely finished steel surfaces. The onset of metal to metal contact was detected by an increase in the frictional drag, and also by the change in electrical conductivity between the pad and collar—an extremely sensitive method. The paper shows that there is, at any rate for this system, a quantitative relation between the total surface roughness of the rubbing surfaces and the calculated oil film thickness both at the initial metal to metal contact and seizure. Initial contact occurs when the outlet film thickness, calculated from normal hydrodynamic theory, falls to three times the maximum surface roughness and seizure occurs when it is double the average roughness.

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Effect of Rolling Velocity and Maximum Hertzian Pressure on Fluid Film in Steady State EHL Line Contact with Rough Surface and Linear Piezoviscosity

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.1371 ◽

2014 ◽

Vol 592-594 ◽

pp. 1371-1375

Author(s):

Nitesh Talekar ◽

Punit Kumar

Keyword(s):

Surface Roughness ◽

Steady State ◽

Film Thickness ◽

Rough Surface ◽

Computer Code ◽

Fluid Film ◽

Line Contact ◽

Rolling Velocity ◽

Load Carrying ◽

Lubricated Contact

Consideration of surface roughness in steady state EHL line contact is the first step towards understanding the lubrication of rough surface problem. Current paper investigates the use of sinusoidal waviness in the contact; more precisely it gives performance of real fluid in EHL line contact. The effect of various parameters like rolling velocity (U) and maximum Hertzian pressure (ph) on surface roughness by using properties of linear and exponential piezo-viscosity is taken into consideration to evaluate behavior of pressure distribution of load carrying fluid film and film thickness. Full isothermal, Newtonian simulation of EHL problem gives described effects. Spiking or fluctuation of pressure and film thickness curves is expected to show presence of irregularities on the surface chosen and amount of fluctuation depends on certain parameters and intensity of irregularities present. Rolling side domain of-4.5 ≤ X ≤ 1.5 with grid size ∆X=0.01375 is selected. A computer code is developed to solve Reynolds equation, which governs the generation of pressure in the lubricated contact zone is discritized and solved along with load balance equation using Newton-Raphson technique.

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Film thickness averaging in compressible lubricating films having stationary surface roughness.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.55.2864 ◽

1989 ◽

Vol 55 (519) ◽

pp. 2864-2872

Author(s):

Yasunaga MITSUYA ◽

Takefumi HAYASHI

Keyword(s):

Surface Roughness ◽

Film Thickness ◽

Stationary Surface

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Mechanical characterization of porous asphalt mixes modifying the asphalt with fatty acid amides -FAA-

Ingeniería e Investigación ◽

10.15446/ing.investig.v37n1.57158 ◽

2017 ◽

Vol 37 (1) ◽

pp. 43 ◽

Cited By ~ 3

Author(s):

Vanessa Senior Arrieta ◽

Jorge Eliecer Córdoba Maquilon

Keyword(s):

Fatty Acid ◽

Mechanical Characterization ◽

Experimental Methodology ◽

Chemical Additives ◽

Asphalt Mixes ◽

Porous Asphalt ◽

Fatty Acid Amides ◽

Pavement Structures ◽

And Performance

Porous asphalt mixes (PAM), form a special road surface for asphalt pavement structures, have a special particle size distribution that lets infiltrate to the runoff storm water through of it because of its voids content about 20 %. Many researchers conducted studies and have concluded that the use of modified asphalts is completely necessary to design PAM. Organic and chemical additives and special procedures as foamed asphalt have enhanced the performance of PAM, during their service life. This paper is focused on the mechanical characterization of PAM and how the asphalt modified with fatty acid amides, influenced on their behavior and performance. Based on an experimental methodology with laboratory tests aimed at establishing a comparison between porous asphalt mixes, using for its design and production a penetration 60-70 pure asphalt and another one asphalt modified with fatty acid amides.

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