Adhesion and Autohesion of Rubber Compounds: Effect of Surface Roughness

1995 ◽  
Vol 68 (1) ◽  
pp. 13-25 ◽  
Author(s):  
A. N. Gent ◽  
S-M. Lai
Keyword(s):  
Surface Roughness ◽  
Smooth Surface ◽  
Peel Strength ◽  
The Other ◽  
Rubber Compound ◽  
Rubber Compounds ◽  
Roughened Surface ◽  
Styrene Butadiene ◽  
Effect Of Surface ◽  
Strength Of Adhesion

Abstract Sheets of various rubber compounds were pre-molded using different mold surfaces: Mylar film, smooth steel, and roughened steel. Two sheets of the same compound were then bonded together by crosslinking them in contact. Measurements of peel strength were carried out over a range of temperatures from −40°C to + 130°C. When an uncured sheet was crosslinked in contact with a smooth fully-cured sheet, the peel strength was generally lower than the tear strength of either sheet and the degree of interlinking was inferred to be only about one-half of the degree of crosslinking. On the other hand, when a sheet was cured in contact with a rough surface the strength of adhesion was 2× to 3× higher than with a smooth surface, probably because of increased area for bonding. Thus, when a rubber compound was cured in contact with a fully-cured sheet having a roughened surface, the two effects largely cancelled out and the resultant bond was about as strong as the material itself. Examples are given for carbon-black-filled and unfilled compounds based on polybutadiene, a styrene-butadiene copolymer, and natural rubber.

Effect of Surface Roughness on the Total Hemispherical and Specular Reflectance of Metallic Surfaces

1964 ◽  
Vol 86 (2) ◽  
pp. 193-199 ◽  
Author(s):  
R. C. Birkebak ◽  
E. M. Sparrow ◽  
E. R. G. Eckert ◽  
J. W. Ramsey
Keyword(s):  
Surface Roughness ◽  
Black Body ◽  
Black Body Radiation ◽  
The Other ◽  
Angle Of Incidence ◽  
Metallic Surfaces ◽  
Specular Reflectance ◽  
Other Hand ◽  
Hemispherical Reflectance ◽  
Effect Of Surface

Measurements have been made of the hemispherical and specular reflectance of metallic surfaces of controlled roughness. The surfaces, which were ground nickel rectangles, were irradiated at various angles of incidence by a beam of black-body radiation, the temperature of which was also varied. The instrumentation which was devised to perform the experiments is described. The measurements show that beyond a certain surface roughness, the hemispherical reflectance is virtually independent of further increases in roughness. On the other hand, the specular reflectance decreases steadily with increasing roughness. Additionally, the hemispherical reflectance is found to be quite insensitive to the angle of incidence, while the specular reflectance increases with angle of incidence for the rougher surfaces.

Elastomer Blends

1974 ◽  
Vol 47 (3) ◽  
pp. 481-510 ◽  
Author(s):  
P. J. Corish ◽  
B. D. W. Powell
Keyword(s):  
Block Copolymers ◽  
Propylene Oxide ◽  
Polymer Chains ◽  
Rubber Compound ◽  
Repeat Units ◽  
Rubber Compounds ◽  
Broad Concept ◽  
Poly Propylene ◽  
Styrene Butadiene ◽  
Composite Article

Abstract Mixtures are difficult to define within the range of materials employed in the rubber and plastic industries. A composite article such as a tire is a mixture of wire (metal), textile cord (organic fiber), and rubber compounds. The rubber compound itself is a mixture of elastomer, filler, and, usually, extender. Moreover, the elastomer may be a mixture of two or more rubbers. On a smaller scale, the elastomer may contain ‘blocky’ segments or crystalline portions along the polymer chains which act as ‘reinforcing’ agents or stiffeners. These may be similar to the repeat units of the elastomeric part, e.g., isotactic—atactic block copolymers of poly(propylene) or poly(propylene oxide); or different from it, as in the stereo block styrene—butadiene thermoplastic copolymers. Two types of elastomer may of course, be copolymerized or one elastomeric type may be grafted onto another. Furthermore, certain catalysts could cause simultaneous homopolymerization of two monomers. All the foregoing systems are different facets of the broad concept of blends, but some selection is obviously needed. In this review, most emphasis will be placed on elastomer—elastomer blends including their preparation from the constituent elastomers. Reference will be made to elastomer—plastic blends prepared from separate materials and by block/graft type reactions. Blends of one plastic with another lie outside the scope of this review.

Effect of Surface Roughness on Fouling of Calcium Carbonate: An Experimental Investigation

2010 ◽  
Author(s):  
M. Izadi ◽  
D. K. Aidun ◽  
P. Marzocca ◽  
H. Lee
Keyword(s):  
Surface Roughness ◽  
Calcium Carbonate ◽  
Rough Surface ◽  
Smooth Surface ◽  
Rough Surfaces ◽  
Operating Conditions ◽  
Tubular Heat Exchanger ◽  
Analytical Microscopy ◽  
Deposit Layer ◽  
Effect Of Surface

The effect of surface roughness on the fouling behavior of calcium carbonate is experimentally investigated. The real operating conditions of a tubular heat exchanger are simulated by performing prolonged experiments with duration of 3 to 7 days. The solution used is a mixture of sodium bicarbonate and calcium chloride in de-ionized water with the concentration of 0.4 g/l of each. An on-line fouling evaluation system was developed such that the fouling resistance for a selected solution could be measured in real time. The experiments are repeated with the same procedure for 90/10 Cu/Ni tubes with different internal surface roughness. After the experiment the surface is analyzed by analytical microscopy to investigate the morphology of the deposit layer. Comparison of the experimental results of smooth and rough surfaces shows that a combination of aragonite and calcite polymorphs are formed on rough surface while only dendritic porous aragonite crystals are formed on smooth surface. Accordingly, the deposit layer formed on rough surface is denser and has a higher thermal resistance comparing to that formed on smooth surface. The fouling factor-time curves of smooth and rough surfaces obtained by the current experimental study agree with the results found by the analytical microscopy of the surface and show higher fouling resistances for rough surface. Experimental data is significantly important for the design, and formulating operating, and cleaning schedules of the equipment.

The Effect of Surface Roughness on Photoluminescence of Porous Silicon

2000 ◽  
Vol 638 ◽  
Author(s):  
Shunsuke Ogawa ◽  
Nobutomo Uehara ◽  
Masato Ohmukai ◽  
Yasuo Tsutsumi
Keyword(s):  
Surface Roughness ◽  
Porous Silicon ◽  
Blue Shift ◽  
The Other ◽  
Quantum Size ◽  
Silicon Nanostructure ◽  
Pl Emission ◽  
Ftir Absorption Spectra ◽  
Porous Silicon Nanostructure ◽  
Effect Of Surface

AbstractWe studied the effect of surface roughness of Si wafers on porous silicon by means of photoluminescence (PL), Fourier transformed infrared (FTIR) absorption and Raman spectroscopy. We prepared several kinds of Si wafers with a different surface roughness, and then the anodization was performed at a same condition. PL spectra show a blue shift with the increase of surface roughness. The particle size of porous silicon nanostructure becomes the smaller with increasing surface roughness at the same time. On the other hand, FTIR absorption spectra show no difference regardless of surface roughness. The PL emission dependent on the surface roughness originates from a quantum size effect. We infer that the surface roughness causes the concentration of the current during anodization in the area where the radius of the curvature at the surface is small.

scholarly journals The Effect of Surface Area of Silicas on Their Reinforcing Performance to Styrene-butadiene Rubber Compounds

2016 ◽  
Vol 51 (2) ◽  
pp. 128-137 ◽  
Author(s):  
Changseok Ryu ◽  
Sun Jung Kim ◽  
Do Il Kim ◽  
Shinyoung Kaang ◽  
Gon Seo
Keyword(s):  
Surface Area ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Rubber Compounds ◽  
Styrene Butadiene ◽  
Effect Of Surface

Investigation on Effect of Surface Roughness Pattern to Drag Force Reduction Using Rotary Rheometer

2005 ◽  
Vol 128 (1) ◽  
pp. 131-138 ◽  
Author(s):  
Chen Haosheng ◽  
Chen Darong ◽  
Li Yongjian
Keyword(s):  
Surface Roughness ◽  
Drag Force ◽  
Smooth Surface ◽  
Side Wall ◽  
Viscous Force ◽  
Longitudinal Groove ◽  
Pressure Drag ◽  
Side Walls ◽  
Force Reduction ◽  
Effect Of Surface

A drag force reduction experiment is performed on polyoxyethylene (PEO) water solution using a rotary rheometer. Longitudinal, transverse, and isotropic grooves are notched on the rotor’s surface to investigate the effect of surface roughness patterns. The experiment results show that higher drag force is generated on the surface with transverse grooves compared with the drag force on a smooth surface, while lower drag force is generated on the surface with longitudinal grooves. The drag force on the surface with isotropic grooves is between them. Forces on the side wall of the grooves play important roles in drag force reduction. They are numerically analyzed based on the Navier-Stokes equation using the finite volume method. The viscous force on the groove’s bottom plane is far less than the force on the corresponding plane of the smooth surface, but the drag force on the groove’s surface is compensated either by the pressure drag on the side walls of the transverse groove or by the viscous force on the side walls of the longitudinal groove. The pressure drag on side wall of transverse groove is always higher than the viscous force on side wall of longitudinal groove. The numerical results cope with the experiment results that only the surface with longitudinal grooves can reduce the drag force.

A Study on Heat History of Organic Accelerators in Rubber Stock (BR Base)

1970 ◽  
Vol 43 (4) ◽  
pp. 799-828
Author(s):  
I. Imase
Keyword(s):  
The Other ◽  
Frictional Heat ◽  
Rubber Matrix ◽  
Rubber Compound ◽  
Incremental Effect ◽  
Rubber Compounds ◽  
History Of ◽  
Curing Agents ◽  
Heat History ◽  
Rubber Stock

Abstract Rubber with some exceptions must generally undergo such processes as mastication, mixing, warming-up, extrusion, spreading, calendering, etc. prior to vulcanization under heat to obtain cured articles. Consequently the rubber matrix receives a heat history caused by mechanical frictional heat or the heat which cannot be avoided during these processes. On the other hand, when an uncured rubber compound, ready for vulcanization, containing such curing agents as sulfur, such activators as zinc oxide, and organic accelerators is heated during the processes or during storage between individual processes, each incremental effect of heat is accumulated with time. It is a well-known fact that this accumulation of heat can lead to the trouble of scorching, etc. As a cause for the trouble, organic accelerators seem to play the most important role. A few reports have been published on the action of accelerators under heat, but, to my knowledge, no report is available on the behavior of accelerators in rubber stocks, namely, on the change of the properties of uncured rubber compounds and on its influence on the properties of vulcanizates. This paper shall report these problems, though it describes only the results of the tests carried out under specific conditions.

Flashing Phenomena of Liquid Nitrogen in a Pressure Vessel Under Rapid Depressurizations

2015 ◽  
Author(s):  
Toshiaki Watanabe ◽  
Hironori Maehara ◽  
Makoto Nakamura ◽  
Hiromitsu Ohta ◽  
Shigeru Itoh
Keyword(s):  
Surface Roughness ◽  
Stainless Steel ◽  
Liquid Nitrogen ◽  
Pressure Vessel ◽  
The Other ◽  
Stream Of Consciousness ◽  
Cryogenic Fluids ◽  
Environmental Agreement ◽  
Device Technology ◽  
Effect Of Surface

In recent years in Japan, the demand of cryogenic fluids like a LH2, LNG is increasing because of the advance of fuel cell device technology, hydrogen of engine, and stream of consciousness for environmental agreement. The purpose of this study is to clarify some fundamental features of the flashing of cryogenic fluids. Experiments on flashing of liquid nitrogen were conducted to clarify the effect of surface roughness of a vessel. Two types of pressure vessel were used. One is a vessel made of stainless steel, the other is a vessel made of glass. In the case of glass vessel, many types of boiling have been observed. The degree of superheat at the start of boiling was found to depend strongly on the rate of depressurization.

INFLUENCE OF MASTICATION ON THE MICROSTRUCTURE AND PHYSICAL PROPERTIES OF RUBBER

2021 ◽  
Author(s):  
Koji Okamoto ◽  
Michiharu Toh ◽  
Xiaobin Liang ◽  
Ken Nakajima
Keyword(s):  
Physical Properties ◽  
Elastic Moduli ◽  
Large Diameter ◽  
The Other ◽  
Rubber Matrix ◽  
Interfacial Region ◽  
Rubber Compound ◽  
Atomic Force ◽  
Rubber Compounds ◽  
Isoprene Rubber

ABSTRACT The effects of the masticated state of isoprene rubber (IR) at the carbon black (CB) addition stage on subsequent mixing, microstructure, and physical properties in the case of a kneader with a characteristic large-diameter shaft are investigated by examining the mastication-time dependence. A sufficiently masticated IR shows a shorter black incorporation time, which results in an improved dispersion of CB and better physical properties. Observing the microstructure of a rubber compound using the atomic force microscope–based nanomechanical technique, poor CB dispersion is revealed for insufficient mastication. Specifically, large CB agglomerations surrounded by the interfacial rubber region with higher elastic modulus than that of a rubber matrix are formed. Such a large CB agglomeration, on the other hand, does not appear in rubber compounds with longer mastication times. The thickness of the interfacial region becomes shorter in these cases. These observations are further discussed by the concept of “rheological unit” introduced by Mooney et al. This study demonstrates that the microstructure of a rubber compound is highly heterogenous with rubber regions of different microscopic elastic moduli and that the microstructure has an influence on CB dispersion and the physical properties of rubber.

Sign in / Sign up

Export Citation Format

Share Document