Light Phenomena on Elongating Vulcanized Rubbers

1950 ◽  
Vol 23 (2) ◽  
pp. 332-337
Author(s):  
A. Van Rossem
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Carbon Black ◽  
Barium Sulfate ◽  
High Speed ◽  
Filler Particle ◽  
Light Effect ◽  
Dark Room ◽  
Rubber Filler

Abstract A description is given of a light phenomenon, first observed by W. C. Smith, when carrying out tear tests on some loaded vulcanized rubbers in a dark room. This phenomenon has been studied more systematically by high-speed extension tests. It appears that this light effect has nothing to do with the choice of accelerators, but with the compounding ingredients of loaded vulcanized rubbers. In general, those compounding ingredients which belong to the filler class, such as whiting, talc, and ground barium sulfate, show this light phenomenon very distinctly, while vulcanized rubbers with reinforcing compounding ingredients, such as zinc oxide, titanium dioxide, and carbon black, do not show any light effect when quickly extended. In accordance with this, Kalite and Calcene, which behave as reinforcing compounding ingredients, do not show any light phenomenon. It seems probable, that, on elongating the vulcanized rubbers containing fillers, the adhesion of rubber-filler particle is broken, and electrical charges appear on an extremely large surface, which lead to innumerable discharges into surrounding vacuoles, causing the general light phenomenon observed.

Ion-Exchange Paper—X-Ray Emission Procedure for Determination of Microgram Quantities of Mercury

1964 ◽  
Vol 47 (2) ◽  
pp. 391-394
Author(s):  
William B Link ◽  
Keith S Heine ◽  
J H Jones ◽  
Percy Wattlington
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Emission Spectroscopy ◽  
Barium Sulfate ◽  
Magnesium Stearate ◽  
Magnesium Carbonate ◽  
Acid Solutions ◽  
X Ray ◽  
Aqueous Acid

Abstract A method has been developed for determining 1 μg of mercury in 100 ml of aqueous acid solution with a precision of ± 0.25 μg. In the method, the mercury is adsorbed by anion resinloaded paper and determined by X-ray emission spectroscopy. The method gave 75—125% recoveries of 1 μg of mercury from acid solutions containing 10 g of sodium sulfate, sodium chloride, iron oxide, magnesium carbonate, and calcium carbonate, and satisfactory recoveries from the HCl extract of carbon, barium sulfate, chromic oxide, bentonite, kaolin, talc, titanium dioxide, and magnesium stearate. Substantial changes in flow rate or acid concentration seem to have little effect on mercury absorption from HC1 solution. Mercury in zinc oxide or bismuth oxychloride cannot be determined by this technique.

The Reinforcing Action and Other Properties of Titanium Fillers in Rubber Stocks

1933 ◽  
Vol 6 (1) ◽  
pp. 106-110
Author(s):  
W. H. Bodger ◽  
F. H. Cotton
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Tensile Properties ◽  
Barium Sulfate ◽  
High Grade ◽  
Reinforcing Agent ◽  
Aging Properties ◽  
Low Volume ◽  
Titanium White ◽  
Better Than

Abstract (1) The reinforcing properties of a high-grade titanium white, containing 74 per cent barium sulfate in intimate combination with the oxide, are slightly better than those of “White Seal” zinc oxide in mixes vulcanized with diphenylguanidine. (2) Titanium dioxide is generally inferior to titanium white as a reinforcing agent, and at high loadings gave poor tensile properties, especially in compounds accelerated with mercaptobenzothiazole. (3) The titanium fillers are incapable of behaving as activators of organic accelerators, as zinc oxide does, and from 3 to 5 per cent of zinc oxide is required in the majority of titanium stocks containing organic accelerators. (4) The aging properties of compounds reinforced with titanium fillers are generally similar to those conferred by zinc oxide, but are inferior to the latter at low volume loadings. (5) Better pigmentary and water-resisting properties are conferred by titanium dioxide than by titanium white, and both these fillers are superior to zinc oxide in these respects.

Breakage of Rubber-Filler Linkages and Energy Dissipation in Stressed Rubber

1955 ◽  
Vol 28 (2) ◽  
pp. 540-556
Author(s):  
A. F. Blanchard
Keyword(s):  
Tensile Strength ◽  
Energy Dissipation ◽  
Carbon Black ◽  
Filler Particle ◽  
Particle Diameter ◽  
Interfacial Area ◽  
Synthetic Rubber ◽  
Common Distribution ◽  
Energy Dissipated ◽  
Rubber Filler

Abstract The marked softening of reinforced rubber by applied stress can be interpreted in terms of a range of strengths of secondary linkages formed by rubber-filler attachments, and this can be described by one common distribution parameter K for several grades and types of filler in natural rubber, and also for at least one type of carbon black in Krylene (GR-S) synthetic rubber. Linkages of this type are of little significance in reinforcement, judged by tensile strength or abrasion resistance. The fact that the filler particle diameter had no influence in these experiments on the energy dissipated in breaking secondary linkages, or their number as reflected by their stiffening action, may be considered a serious objection to the presumption that specific surface or interfacial area determines linkage formation in rubber and, hence (supposedly), the reinforcement. There is evidence of primary (strong) linkages introduced by carbon blacks, and these are likely to have a more important role in determin- ing the breaking, tearing, and abrasion of rubber.

Limiting Law of the Reinforcement of Rubber

1945 ◽  
Vol 18 (2) ◽  
pp. 292-305 ◽  
Author(s):  
Hugh M. Smallwood
Keyword(s):  
Molecular Structure ◽  
Experimental Data ◽  
Particle Size ◽  
Zinc Oxide ◽  
Carbon Black ◽  
Filler Particle ◽  
Rubber Matrix ◽  
Volume Loading ◽  
Volume Percentage ◽  
Filler Particles

Abstract 1. Analysis shows that, subject to certain limitations, the modulus of a loaded stock (M*) depends on the modulus of the rubber matrix (M), according to the equation: M*=M(1+2.5ϕ) where 100ϕ is the volume percentage of filler. When these limitations are fulfilled, the effect of compounding on modulus is, therefore, independent of the particle size of the filler. The assumptions on which this equation is founded are as follows: (1) the filler particles are spherical; (2) there is complete adhesion between rubber and filler; (3) the elongation is small; (4) the filler is completely dispersed; (5) the volume loading is small; (6) the filler particles are sufficiently large that the molecular structure of the rubber may be neglected. 2. The stresses about a filler particle have been derived mathematically. 3. Experimental data check the calculations for the following fillers: P-33, Thermax, and whiting. Catalpo clay presents some anomalies because of its acicular particles. 4. Carbon black does not conform to the calculations. This is attributed to the fact that it is strongly flocculated in rubber. 5. Zinc oxide (Kadox or XX zinc oxide), which should conform, because it is well dispersed in rubber, causes abnormally large increases in modulus, presumably because of alteration of the type of cure and consequent alteration of the modulus of the rubber matrix.

Extraction and identification of fillers and pigments from pyrolyzed rubber and tire samples

1996 ◽  
Vol 54 ◽  
pp. 174-175
Author(s):  
P. Sadhukhan ◽  
J. B. Zimmerman
Keyword(s):  
Zinc Oxide ◽  
Electron Microscope ◽  
Carbon Black ◽  
Natural Rubber ◽  
Transmission Electron Microscope ◽  
Rolling Resistance ◽  
Synthetic Polymers ◽  
Nitrogen Atmosphere ◽  
Transmission Electron ◽  
Curing Agents

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.

Development and production experience of the multilayer curtain-coated linerboard of Ji’an PM No. 3,

TAPPI Journal ◽  
2014 ◽  
Vol 13 (2) ◽  
pp. 17-25
Author(s):  
JUNMING SHU ◽  
ARTHAS YANG ◽  
PEKKA SALMINEN ◽  
HENRI VAITTINEN
Keyword(s):  
Titanium Dioxide ◽  
High Speed ◽  
Food Packaging ◽  
Production Efficiency ◽  
Positive Impact ◽  
Low Cost ◽  
Board Structure ◽  
Flexographic Printing ◽  
Curtain Coating ◽  
Coating Formulations

The Ji’an PM No. 3 is the first linerboard machine in China to use multilayer curtain coating technology. Since successful startup at the end of 2011, further development has been carried out to optimize running conditions, coating formulations, and the base paper to provide a product with satisfactory quality and lower cost to manufacture. The key challenges include designing the base board structure for the desired mechanical strength, designing the surface properties for subsequent coating operations, optimizing the high-speed running of the curtain coater to enhance production efficiency, minimizing the amount of titanium dioxide in the coating color, and balancing the coated board properties to make them suitable for both offset and flexographic printing. The pilot and mill scale results show that curtain coating has a major positive impact on brightness, while smoothness is improved mainly by the blade coating and calendering conditions. Optimization of base board properties and the blade + curtain + blade concept has resulted in the successful use of 100% recycled fiber to produce base board. The optical, mechanical, and printability properties of the final coated board meet market requirements for both offset and flexographic printing. Machine runnability is excellent at the current speed of 1000 m/min, and titanium dioxide has been eliminated in the coating formulations without affecting the coating coverage. A significant improvement in the total cost of coated white liner production has been achieved, compared to the conventional concept of using virgin fiber in the top ply. Future development will focus on combining low cost with further quality improvements to make linerboard suitable for a wider range of end-use applications, including frozen-food packaging and folding boxboard.

Mycosynthesis of bimetallic zinc oxide and titanium dioxide nanoparticles for control of Spodoptera frugiperda

2021 ◽  
pp. 104910
Author(s):  
Jayaraman Kumaravel ◽  
Kandhasamy Lalitha ◽  
Murugan Arunthirumeni ◽  
Muthugounder Subramanian Shivakumar
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Spodoptera Frugiperda ◽  
Titanium Dioxide Nanoparticles

Ionic Crosslinking of Carboxylated SBR

1983 ◽  
Vol 56 (5) ◽  
pp. 942-958 ◽  
Author(s):  
Kyosaku Sato
Keyword(s):  
Zinc Oxide ◽  
Carbon Black ◽  
Elevated Temperatures ◽  
Ion Clusters ◽  
Ionic Crosslinking ◽  
Reinforcing Fillers ◽  
Ionic Bonds ◽  
Tan Δ ◽  
And Shifts ◽  
Ionic Crosslinks

Abstract 1. Ionic bonding of carboxylated SBR with zinc oxide is detectable by means of measurements of the temperature dependence of tan δ. There is an α peak in the region of 60°C at 3.5 Hz. The position and shape of the α peak are strongly dependent on the state of cure of the vulcanizates. Without permanent crosslinking, the α peak is a plateau; as the crosslink density increases, the α peak becomes sharper and shifts to lower temperatures. The presence of carbon black causes the α peak to shift to higher temperatures, regardless of the presence of permanent crosslinks. 2. Ionic bonds in carboxylated SBR reacted with zinc oxide are in the form of ion clusters which function as crosslinks at room temperature. The ionic crosslinks provide carboxylated SBR with high tensile strength in the absence of reinforcing fillers. The presence of carbon black causes the 300% modulus to increase. The ionic crosslinks are labile, and the strength is lost at moderately elevated temperatures. A mixed cure system consisting of both sulfur and zinc oxide provides higher heat resistance than either of the single cure systems.

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