Influence of Moisture Content of Carbon Black on Rubber Properties

1941 ◽  
Vol 33 (9) ◽  
pp. 1183-1185
Author(s):  
Leonard H. Cohan ◽  
C. R. Johnson
Keyword(s):  
Carbon Black ◽  
Moisture Content

Effect of Moisture on Curing Rate of GR-S

1945 ◽  
Vol 18 (1) ◽  
pp. 141-148 ◽  
Author(s):  
H. A. Braendle ◽  
W. B. Wiegand
Keyword(s):  
Carbon Black ◽  
Moisture Content ◽  
Storage Time ◽  
Laboratory Scale ◽  
Water Addition ◽  
Moisture Retention ◽  
Effect Of Moisture ◽  
Mixed Stock ◽  
Temperature Storage

Abstract 1. Moisture content of uncured GR-S compounds must be reckoned with because of its effect on curing rate and the serious consequence of overcure. 2. Excessively dry polymer (below about 0.15 per cent water) will, in general, be slow curing (Figure 2). 3. Mixed stock with less than 0.5 per cent water will, in general, be slow curing and erratic in curing rate (Figure 5). 4. The normal moisture range of carbon black does not affect the curing rate of GR-S (Figure 4). 5. The normal moisture content of carbon black is not available to the polymer for stabilizing its curing rate. 6. Mixed stock which is dry and slow curing may be conditioned to stable curing rate by storage under humid conditions. A moisture content of 0.5 to 1.0 per cent is indicated. This moisture content seems also to iron out differences in curing rate between polymers. 7. Since conditioning of mixed stocks is not always feasible on the factory scale, the stabilization of cure by direct water addition during mixing should be given consideration. 8. Laboratory-scale tests on a GR-S tread compound indicate that an addition of about 2.5 to 5 per cent water (on the polymer) during mixing will result in a mixed-stock moisture content giving minimal cure variation for normal-curing and slow-curing (very dry) polymers for periods of stock layover up to about 3 weeks. 9. Any additions of water as suggested above will, on the factory scale, require adjustment, since moisture retention is a function of the compounding ingredients, mixing cycle and temperature, storage time, and humidity conditions actually obtaining.

Influence of Moisture Content of Carbon Black on Rubber Properties

1942 ◽  
Vol 15 (1) ◽  
pp. 216-219
Author(s):  
Leonard H. Cohan ◽  
C. R. Johnson
Keyword(s):  
Carbon Black ◽  
Moisture Content ◽  
Mean Value ◽  
Average Deviation ◽  
Maximum Accuracy ◽  
Series Of Experiments ◽  
The Mean ◽  
Adsorbed Moisture

Abstract The moisture content of carbon black should be kept approximately constant if maximum accuracy in rubber testing is to be attained. In this laboratory we have found it convenient to equilibrate blacks at about 30 per cent humidity, under which condition most rubber channel blacks adsorb 1.5 to 2.0 per cent water. In the case of most of the properties of tread stocks, this precaution decreases the average deviation from the mean value in any series of experiments. In the case of extrusion tests, the effect of adsorbed moisture is so great that the use of a standard moisture content, or at least the determination of moisture content at the same time as the black is milled for extrusion, is necessary if reproducible results are to be expected.

scholarly journals THE USE OF MODIFIED SUGARCANE BAGASSE IN NATURAL RUBBER COMPOUNDING

2020 ◽  
Vol 45 (6) ◽  
Author(s):  
A.K. Akinlabi ◽  
R.N. Laleye ◽  
S. B. Akinfenwa ◽  
A.M Mosaku ◽  
A. A. Falomo ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Moisture Content ◽  
Natural Rubber ◽  
Sugarcane Bagasse ◽  
Agricultural Waste ◽  
Natural Rubber Latex ◽  
Total Solid Content ◽  
Pixe Analysis ◽  
Better Than

Natural rubber (NR) is a renewable agricultural resource which has gained fast technological innovation due to some inherent properties and its renewability. Compounding of natural rubber with modified and unmodified nano-sized agricultural waste is of interest because it is economical, environmentally friendly, cheap and readily available, hence, the trial of sugarcane bagasse as an additive in Natural Rubber compounding. The sugarcane bagasse was sourced locally, milled to fine powder and sieved to <100µm in size. Characterization of Natural rubber latex viz-a-viz: Dry rubber content (DRC), Total solid content (TSC), Ash content, Moisture content were carried out. The Sugarcane bagasse was modified via Hydroxylation using 10% Sodium hydroxide (NaOH). The modified sugarcane baggase (MSB) and unmodified sugarcane baggase (USB) were characterized viz-a-viz: their pH, moisture content, Fourier transform infrared spectroscopy and micro-pixe analysis. The extent of modification was determined via titration. The NR was thereafter compounded with USB, MSB, CB, admix of MSB with CB and admix of USB with CB to give five vulcanizates, labeled A – E ( A- 40 parts CB, B- 40 parts USB, C- 40 parts MSB, D- 20 CB : 20 USB while E was 20 CB : 20 MSB). The vulcanizates were then subjected to physico-mechanical tests viz-a-viz: Tensile strength, Modulus Elasticity, Hardness, Elongation @ break and Yield elongation. The result revealed that mix A (control) with 40 CB has the highest Tensile strength compared to the other mixes, which was followed by mixes E >D >C while B gave the least tensile strength, showing that carbon black acted better than modified sugarcane bagasse and better than unmodified sugarcane bagasse. Compatibility of the unmodified and hydroxylated sugarcane bagasse with natural rubber and carbon black was also established. The extent of the solubility of the mixes in ethanol, kerosene and petrol were investigated to determine the extent of crosslinking and mix A was very resistant to all the solvents followed by mixes C then E then D while mix B dissolves readily.

Effect of Moisture on GR-S Rate of Cure and Physical Properties

1946 ◽  
Vol 19 (3) ◽  
pp. 773-780
Author(s):  
Ian C. Rush
Keyword(s):  
Carbon Black ◽  
Moisture Content ◽  
Physical Properties ◽  
Testing Methods ◽  
Stress Strain ◽  
Moisture Contents ◽  
Strain Data ◽  
Water Curing ◽  
Effect Of Moisture ◽  
The Individual

Abstract Moisture has been discussed as a factor which may give rise to variable rates of cure of GR-S. This moisture may be present in GR-S itself or in the compounding ingredients used. Accordingly, a program was initiated in the spring of 1944 to establish the influence of moisture, not only on the rate of cure of GR-S, but also on its physical properties. Since that time two papers have been published on this subject by other investigators. The results reported here verify some of the conclusions drawn by these investigators but seem to be at variance with others. In this study various proportions of water were added in the following ways : by premixing with carbon black, by adding directly on the mill rolls at the completion of normal milling, and by soaking GR-S crumb in water. Curing curves were obtained for each batch, and were used to evaluate the rate of cure. To eliminate day-to-day variations in physical properties due to error in testing methods, three batches of different moisture contents were mixed and tested on the same day. This same group was then remixed and tested on successive days until at least three batches had been tested for each moisture content and each method of addition. The averages of the individual results (stress-strain data and percentage moisture retained) on batches to which the same percentage of water was added, were then considered free from day-to-day variations.

A Preparation of High Resolution Standards for Electron Microscopy. Part II

1971 ◽  
Vol 29 ◽  
pp. 160-161
Author(s):  
Akira Tanaka ◽  
David F. Harling
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Carbon Black ◽  
Single Crystal ◽  
Dark Field ◽  
Graphitized Carbon Black ◽  
Graphitized Carbon ◽  
Dark Field Imaging ◽  
Crystal Films ◽  
Micro Holes

In the previous paper, the author reported on a technique for preparing vapor-deposited single crystal films as high resolution standards for electron microscopy. The present paper is intended to describe the preparation of several high resolution standards for dark field microscopy and also to mention some results obtained from these studies. Three preparations were used initially: 1.) Graphitized carbon black, 2.) Epitaxially grown particles of different metals prepared by vapor deposition, and 3.) Particles grown epitaxially on the edge of micro-holes formed in a gold single crystal film.The authors successfully obtained dark field micrographs demonstrating the 3.4Å lattice spacing of graphitized carbon black and the Au single crystal (111) lattice of 2.35Å. The latter spacing is especially suitable for dark field imaging because of its preparation, as in 3.), above. After the deposited film of Au (001) orientation is prepared at 400°C the substrate temperature is raised, resulting in the formation of many square micro-holes caused by partial evaporation of the Au film.

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.

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