The Organic Nature of Carbon Black Surfaces

1958 ◽  
Vol 31 (4) ◽  
pp. 941-952
Author(s):  
Jules V. Hallum ◽  
Harry V. Drushel
Keyword(s):  
Carbon Black ◽  
Functional Groups ◽  
Chemical Interaction ◽  
Hydroxyl Groups ◽  
Carbon Blacks

Abstract Evidence is presented for the existence of quinone groups and aromatic hydroxyl groups on the surface of carbon black particles. This evidence is based largely upon polarographic analyses of slurries of carbon blacks. A mechanism for the chemical interaction of carbon blacks with elastomers is proposed on the basis of these functional groups.

Antioxidant Properties of Carbon Black in Unsaturated Elastomers. Studies with cis-Polybutadiene

1965 ◽  
Vol 38 (3) ◽  
pp. 636-646
Author(s):  
J. T. Gruver ◽  
K. W. Rollmann
Keyword(s):  
Antioxidant Activity ◽  
Carbon Black ◽  
Antioxidant Properties ◽  
Chain Scission ◽  
Oxygen Absorption ◽  
Hydroxyl Groups ◽  
Carbon Blacks ◽  
Crosslinking Reactions ◽  
Absorption Measurements

Abstract The thermal antioxidant behavior of carbon black was studied in vulcanized cis-polybutadiene and related to the surface chemistry of the black. Continuous and intermittent stress relaxation and oxygen absorption measurements were employed to determine the antioxidant ability of the carbon blacks. The blacks were characterized by the surface concentrations of oxygen-containing functional groups, using methods described in the literature. Antioxidant activity was found to be highest in carbons containing relatively large amounts of bound oxygen. These carbons are also acidic and decompose peroxides by the ionic mechanism. This was demonstrated with cumyl peroxide. However, even though the acidity and ability to decompose cumyl peroxide to phenol and acetone could be destroyed by methylation, this treatment did not seriously impair the antioxidant activity, so that the role of acidic groups appears to be minor. Evidence is presented which suggests strongly that the antioxidant behavior of carbon blacks is due to surface quinones, possibly hydrogen-bonded with adjacent hydroxyl groups. Measurements made on samples vulcanized in peroxide and sulfur curing systems indicate that the antioxidant behavior of carbon black is independent of the method of vulcanization in the absence of other antioxidants. A characteristic feature of the antioxidant action of carbon blacks is their tendency to repress the oxidative crosslinking reactions, the relative amount of compensation of chain scission by crosslinking being smaller than in gum vulcanizates.

Scorching of Rubber Mixes. I. Structural Changes in Unfilled and Filled Stocks

1962 ◽  
Vol 35 (2) ◽  
pp. 509-516
Author(s):  
B. A. Dogadkin ◽  
A. V. Dobromyslova ◽  
O. N. Belyatskaya ◽  
T. A. Gyul'-Nazarova
Keyword(s):  
Carbon Black ◽  
Functional Groups ◽  
Significant Influence ◽  
Fine Particle ◽  
Structural Changes ◽  
Ph Value ◽  
Important Influence ◽  
The Other ◽  
Flow State ◽  
Carbon Blacks

Abstract 1. In the process of scorching there takes place a combination of the sulfur with the rubber. The flow of unfilled stocks heated at 120° ceases at the instant of combination of ∼0.5% sulfur reckoned on the stock. 2. In carbon black filled stocks there is an increase in the rate of combination of sulfur with rubber and a decrease in the time for which the stock is in the flow state, as the pH value of the carbon black added to the stock increases. 3. In processing a stock on the mill in the presence of fine-particle carbon black there is formed a rubber-carbon black gel, the amount of which hardly changes in the process of heating the stock in the plastimeter at 120°; only at the instant of cessation of the flow of the stock does its solubility decrease perceptibly. 4. In filled stocks in which a rubber-carbon black gel is formed in the course of treatment on the mill, the limiting amount of bound sulfur combined at the instant of cessation of the flow of the stock is less than in stocks in which no rubber-carbon black gel is formed. 5. Alteration in the amount of oxygen-containing functional groups upon the surface of the carbon black does not cause any important influence upon the amount of rubber-carbon black gel, but significantly alters the rate of combination of sulfur with rubber and the tendency of the stock to premature vulcanization. 6. Thus the phenomenon of premature vulcanization is governed for the most part by the reaction of the rubber with the sulfur and the other vulcanizing agents. In stocks with fine-particle carbon blacks there is also a significant influence from the formation of the rubber-carbon black gel in the processing of the stock on the mill.

scholarly journals INVESTIGATION OF REACTIONS OF INTERACTION OF CELLULOSE NITRIC ESTERS WITH CARBOXYLIC ACID CHLORIDES

2021 ◽  
Vol 64 (5) ◽  
pp. 30-34
Author(s):  
Svetlana M. Romanova ◽  
Liliya A. Fatykhova
Keyword(s):  
Carboxylic Acid ◽  
Functional Groups ◽  
Electrophilic Substitution ◽  
Chemical Interaction ◽  
Cellulose Nitrate ◽  
Water Soluble ◽  
Hydroxyl Groups ◽  
Gel Chromatography ◽  
Acid Chlorides ◽  
Cellulose Nitrates

The chemical interaction of high-nitrogen cellulose ether with acetic, propionic, butyric and isobutyric acids has been studied. The general laws and features of the electrophilic substitution of functional groups of cellulose nitroesters are revealed. The preferred directions of the chemical interaction of cellulose nitrate with carboxylic acid chlorides are established: O-acylation of nitrate and hydroxyl groups; O-acylation of the glucopyranose ring; O-acylation of the ether bond with depolymerization of the chain of an SC molecule; hydrolysis of nitrate groups; destruction of the chain of a macromolecule of nitric acid ester with the formation of water-soluble organic compounds. The structure, properties and possibilities of using synthesized mixed cellulose ethers were studied. Effective methods have been developed for the chemical modification of cellulose nitrates with carboxylic acid chlorides. The probable directions of the reaction of the interaction of cellulose nitrates with electrophilic reagents are predicted based on quantum-chemical calculations of point charges on the atoms of the reacting molecules. The reactivity of highly substituted cellulose nitrates in reactions with carboxylic acid chlorides has been established. The optimal conditions for the interaction of cellulose nitrates with carboxylic acid chlorides have been identified and a mathematical model of the reaction kinetics has been constructed. The possibility of a directed change in the composition of chemically modified cellulose nitrates depending on the synthesis conditions has been established. As a result of the combined use of physicochemical research methods, the chemical composition was determined and the structure of the synthesized compounds was determined: cellulose acetyl nitrates, cellulose propionyl nitrates, cellulose butyryl nitrates, and cellulose isobutyryl nitrates. Using gel chromatography, it was found that the molecular weight characteristics of the synthesized samples are directly dependent on the conditions of their synthesis. It was found that electrophilic substitution of the functional groups of cellulose nitrate proceeds more intensively in the pyridine medium.

scholarly journals Mechanical Properties of Graphene Oxide Coupled by Multi-Physical Field: Grain Boundaries and Functional Groups

Crystals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 62
Author(s):  
Xu Xu ◽  
Zeping Zhang ◽  
Wenjuan Yao
Keyword(s):  
Mechanical Properties ◽  
Graphene Oxide ◽  
Grain Boundaries ◽  
Functional Groups ◽  
Oxygen Content ◽  
Tensile Fracture ◽  
Hydroxyl Groups ◽  
Molecular Configuration ◽  
Spatial Design ◽  
Out Of Plane

Graphene and graphene oxide (GO) usually have grain boundaries (GBs) in the process of synthesis and preparation. Here, we “attach” GBs into GO, a new molecular configuration i.e., polycrystalline graphene oxide (PGO) is proposed. This paper aims to provide an insight into the stability and mechanical properties of PGO by using the molecular dynamics method. For this purpose, the “bottom-up” multi-structure-spatial design performance of PGO and the physical mechanism associated with the spatial structure in mixed dimensions (combination of sp2 and sp3) were studied. Also, the effect of defect coupling (GBs and functional groups) on the mechanical properties was revealed. Our results demonstrate that the existence of the GBs reduces the mechanical properties of PGO and show an “induction” role during the tensile fracture process. The presence of functional groups converts in-plane sp2 carbon atoms into out-of-plane sp3 hybrid carbons, causing uneven stress distribution. Moreover, the mechanical characteristics of PGO are very sensitive to the oxygen content of functional groups, which decrease with the increase of oxygen content. The weakening degree of epoxy groups is slightly greater than that of hydroxyl groups. Finally, we find that the mechanical properties of PGO will fall to the lowest values due to the defect coupling amplification mechanism when the functional groups are distributed at GBs.

Radiotracer Studies of Carbon Black Surface Interactions with Organic Systems. I. Experimental Approach and Initial Results from Chemisorption and Vinyl Polymerization Studies

1968 ◽  
Vol 41 (2) ◽  
pp. 382-399 ◽  
Author(s):  
Marvin L. Deviney ◽  
Lawrence E. Whittington
Keyword(s):  
Carbon Black ◽  
Functional Groups ◽  
Reaction Mechanisms ◽  
Hydrogen Abstraction ◽  
Surface Interactions ◽  
Carbon Surface ◽  
Organic Systems ◽  
Carbon Black Surface ◽  
Basic Reaction ◽  
Black Surface

Abstract Radiotracer techniques have been applied to the study of interactions of carbon black surface functional groups with two chosen organic systems. The basic reaction mechanisms demonstrated in this study may have implications in elastomer reinforcement. Direct radiochemical evidence supports the conclusions of Hallum and Drushel (based on less direct polarographic data) that surface quinonic groups exhibit hydrogen abstraction activity toward tertiary hydrogens in paraffinic hydrocarbons. Studies on the system carbon black and styrene using tritium radiotracer have provided direct evidence that phenolic hydrogens participate in the polymerization acceleration and graft polymer formation reaction and are transferred to the growing polystyrene chains as postulated by Donnet. Several methods have been developed for specifically labelling certain oxygenated functional groups on the carbon surface with tritium and for tritium labelling carbon black in aromatic hydrogen positions. The techniques developed in this work and the basic reaction mechanisms derived will permit this investigation to be extended into a radiochemical study of carbon black surface interactions with elastomer related systems of interest to the rubber industry.

A Carbon Black Structure-Concentration Equivalence Principle. Application to Stress-Strain Relationships of Filled Rubbers

1971 ◽  
Vol 44 (1) ◽  
pp. 199-213 ◽  
Author(s):  
Gerard Kraus
Keyword(s):  
Carbon Black ◽  
Primary Structure ◽  
Equivalence Principle ◽  
Chemical Activity ◽  
Cross Linking ◽  
Surface Chemical ◽  
Deformation Structure ◽  
Carbon Blacks ◽  
Filled Rubbers ◽  
Dependent Factor

Abstract It is shown that various modulus values of carbon black reinforced rubber are functions of the product of the actual black loading and a structure dependent factor. The structure factor appears to be a linear function of the so-called 24M4 value of the dibutylphthalate absorption and is independent of elongation, temperature, and degree of cross-linking over the ranges covered by the data reported. An interpretation of the results is offered based on the idea of polymer occluded in the interstices of primary structure aggregates and thereby shielded from deformation. Structure-concentration equivalence can only be demonstrated with carbon blacks differing in (primary) structure alone. Deviations are observed whenever the carbon blacks compared vary significantly in specific surface area and surface chemical activity.

Effect of Palm Kernel Meal as Melamine Urea Formaldehyde Adhesive Extender for Plywood Application: Using a Fourier Transform Infrared Spectroscopy (FTIR) Study

2011 ◽  
Vol 121-126 ◽  
pp. 493-498 ◽  
Author(s):  
Huei Ruey Ong ◽  
Reddy Prasad ◽  
Md. Maksudur Rahman Khan ◽  
Md. Najmul Kabir Chowdhury
Keyword(s):  
Fourier Transform ◽  
Functional Groups ◽  
Chemical Interaction ◽  
Urea Formaldehyde ◽  
Palm Kernel ◽  
Fourier Transform Infrared ◽  
Blue Shift ◽  
Hot Press ◽  
Kernel Meal ◽  
Palm Kernel Meal

Increased demand for wood adhesives, environmental concerns, and the uncertainty of continuing availability of petrochemicals have led to recent attention on protein-based adhesives. This study was conducted to investigate the physico-chemical interaction of palm kernel meal (PKM) with melamine urea formaldehyde (MUF) resins in adhesive formulation by using Fourier Transform Infrared (FTIR) Spectroscopy. The effect of hot press on PKM extender has been investigated by FTIR and blue shift is observed due to the hot press indicating that the functional groups (such as C=O, -OH and NH) are become more free in the samples. In the case of PKM-MUF blend bonding interactions observed where, PKM played the role as an extender. Red shift of C=O and N-H groups stretching in PKM-MUF-Wood blend is observed which suggests the interaction of these functional groups through hydrogen bonding. The results suggest that PKM extender-based MUF adhesive resins have potential application for the production of exterior plywood.

PERMEABILITY STUDIES: III. SURFACE AREA MEASUREMENTS OF CARBON BLACKS

1948 ◽  
Vol 26a (2) ◽  
pp. 29-38 ◽  
Author(s):  
J. C. Arnell ◽  
G. O. Henneberry
Keyword(s):  
Electron Microscope ◽  
Low Temperature ◽  
Carbon Black ◽  
Surface Area ◽  
Satisfactory Agreement ◽  
Nitrogen Adsorption ◽  
Average Particle ◽  
Carbon Blacks ◽  
Permeability Studies ◽  
Nitrogen Adsorption Isotherms

The modified Kozeny equation has been found to be satisfactory for the measurement of the specific surfaces of carbon blacks having average particle diameters ranging from 0.01 to 0.1 μ to within ±10%. Comparative data were obtained from electron microscope counting and from low temperature nitrogen adsorption isotherms. The three methods examined gave results that were in satisfactory agreement, except when the carbon black was porous, and then the adsorption value was extremely large.

CARBON BLACK FOR RACING AND MOTORCYCLE TIRE TREADS. PERFORMANCE MODEL DEVELOPMENT

2011 ◽  
Vol 84 (4) ◽  
pp. 493-506
Author(s):  
Irene S. Yurovska ◽  
Michael D. Morris ◽  
Theo Al
Keyword(s):  
Carbon Black ◽  
Critical Role ◽  
Model Development ◽  
Aggregate Size ◽  
Rolling Resistance ◽  
Performance Model ◽  
Average Life ◽  
Carbon Blacks ◽  
Truck Tires ◽  
And Performance

Abstract Racing tires and motorcycle tires present individual segments of the tire market. For instance, while the average life of car and truck tires is 50 000 miles, the average life of race tires is 100 miles. Because tires play a critical role in a race, technical demands to assure safety and performance are growing. Similarly, tires have a large influence on safety, handling/grip, and performance of the rapidly growing world fleet of motorcycles, due to the fact of only two wheels being in contact with the ground. Thus, the common feature of both market segments is that the typical tire compromise of wear, rolling resistance, and traction is strongly weighted toward traction. Most of the recent efforts of rubber scientists have been directed toward lowering rolling resistance of the tread compounds, which left a certain void in the science of compounding for racing and motorcycle treads. Particularly, the industrial assortment of polymers and fillers used for motorcycle treads is commonly different from that used for car or truck treads, but it is not known how the filler properties affect the hysteresis–stiffness compromise. The objective of this study is to evaluate the effects of the carbon black characteristics on the important properties of a typical racing and motorcycle tire tread compound. More than 50 individual carbon blacks were mixed in a SBR formulation. The acquired data were statistically analyzed, and a linear multiple regression model was developed to relate rubber properties (responses), such as static modulus, complex dynamic modulus, hysteresis, and viscosity to the key carbon black characteristics (variables) of surface area, structure, aggregate size distribution, and surface activity. Prediction profiles created from the model demonstrate rubber performance limits for the range of carbon blacks tested, and indicate the niches to provide required combinations of the rubber properties.

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