Characterization of Polymer Adsorption on Disordered Filler Surfaces by Transversal 1H NMR Relaxation

1997 ◽  
Vol 70 (5) ◽  
pp. 747-758 ◽  
Author(s):  
H. Lüchow ◽  
E. Breier ◽  
W. Gronski
Keyword(s):  
Surface Roughness ◽  
Carbon Black ◽  
1H Nmr ◽  
Nmr Relaxation ◽  
Rubber Matrix ◽  
Adsorption Sites ◽  
Bound Rubber ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Tan Δ

Abstract The transversal 1H NMR relaxation of the bound rubber shell of carbon black loaded elastomers can be decomposed into three relaxation regimes corresponding to the loosely bound rubber, the rubber that is immobilized on the carbon black surface and a third component of intermediate mobility. The relaxation time T2 of the intermediate component is related to the end-to-end distance of polymer segments between adsorption sites on the carbon black surface, by converting the relaxation times to length scales on the basis of recent work on NMR relaxation of elastomeric networks. From measurements on SBR loaded with carbon black N 220, a distance of 2.3 nm was obtained in agreement with characteristic dimensions of crystallite sizes and surface roughness as determined by atomic force and scanning tunneling microscopy. The analysis was applied to novel inversion blacks which give lower tan δ/60°C, and rolling resistance without affecting tan δ/0°C and wet skid behavior. These blacks were found to possess a higher density of adsorption sites and a greater surface roughness as compared to standard carbon blacks. In addition to the surface characterization, the analysis of the mobile component of the compound allowed the estimation of the density of entanglement couplings between the rubber matrix and the bound rubber shell.

New Studies on the Surface Properties of Carbon Blacks

1990 ◽  
Vol 63 (5) ◽  
pp. 747-778 ◽  
Author(s):  
J. A. Ayala ◽  
W. M. Hess ◽  
A. O. Dotson ◽  
G. A. Joyce
Keyword(s):  
Carbon Black ◽  
Hydrogen Content ◽  
Surface Reactivity ◽  
Moisture Adsorption ◽  
Carbon Blacks ◽  
Surface Sites ◽  
Bound Rubber ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Polymer Interaction

Abstract A series of carbon blacks of widely varying morphology and microstructure were analyzed for surface compositional properties employing SIMS, XPS/ESCA, and GC-MS. These studies were supported by bulk analyses for hydrogen and oxygen content. Surface reactivity was assessed by means of inverse gas chromatography, moisture adsorption, and oxidation in an oxygen plasma. To directly assess carbon-black-polymer interaction, the carbon blacks were evaluated in SBR and IIR compounds for stress-strain and dynamic properties as well as bound rubber. The major findings of these studies are: 1. The combined results of hydrogen content, SIMS, and pyrolysis-GC-MS suggest a complex hydrogen functionality at the carbon-black surface, which governs the level of interaction with elastomers. 2. SIMS analyses have shown that the hydrogen functionality at the carbon-black surface is preserved after an 1173 K heat treatment in an inert atmosphere. 3. Gas-solid chromatography results indicate that this technique may be very useful to determine the degree of heterogeneity of a carbon-black surface. It also provides a tool to characterize the nature of the surface sites which are responsible for such a heterogeneity. 4. Moisture-adsorption rates provides a means to explore the reactivity of carbon-black-surface sites. Initial rates of adsorption can be well explained by a second-order-rate mechanism. 5. Bound-rubber development (SBR) and oxygen content per square meter of carbon-black-surface area were directly proportional to the hydrogen content of the black. The hydrogen content is considered to be the primary compositional factor relating to carbon-black-surface activity, while bound rubber and oxygen levels are specific measures of surface reactivity. 6. The slope of the stress-strain curves (or the modulus value) in the λ=1 to 3 region divided by the black networking factor, η (E′ at 2% ptp ÷ at 25% ptp), is sensitive to changes in black-polymer interaction. This ratio (σ/η or M/η) shows an excellent correlation with black hydrogen content and bound rubber (SBR). 7. The σ/η values for SBR and IIR are highly correlated, although the values for SBR are two to three times higher, and there was no measurable bound rubber for any of the IIR compounds. 8. The σ/η values for IIR (λ=2−3) and the oxygen/m2 values were found to be the best discriminators for black-polymer interaction in explaining within-grade treadwear variations in SBR/BR multisection radial-passenger treads.

The Effect of Carbon Black Surface Properties and Structure on Rheometer Cure Behavior

1972 ◽  
Vol 45 (1) ◽  
pp. 129-144 ◽  
Author(s):  
G. R. Cotten
Keyword(s):  
Carbon Black ◽  
Surface Chemistry ◽  
Acid Concentration ◽  
Crosslink Density ◽  
Rubber Matrix ◽  
Total Acid ◽  
Cure Behavior ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Filler Structure

Abstract The cure behavior of SBR and NR compounds was examined using the Monsanto Rheometer. The three cure parameters—induction period (td), rate of crosslinking reaction (k2) and maximum increase in torque (ΔL)—were derived from the Rheometer torque curves. The data so obtained were used to calculate Westlinning's αF-values. It was shown that (1) k2 decreases with increasing total acid concentration at the carbon black surface and (2) the value of αF is related to the filler structure and the crosslink density of the rubber matrix. It was also demonstrated that the crosslink density, as measured by ΔL, is influenced by the surface chemistry of carbon black. In SBR stocks the crosslink density increases with increasing total acid concentration, while in NR compounds the reverse is true. These findings were confirmed by examining the tensile properties of regular and oxidized HAF-LS black in SBR and NR compositions. Thus the effect of carbon black surface chemistry on crosslink density can be estimated, for a given recipe, from the value of k2. An empirical relationship between the cure parameters (αF and k2) and filler structure (as measured by extrusion shrinkage) was derived and tested on a wide range of carbon blacks. This relation gives a much better correlation coefficient than the simple relation between extrusion shrinkage and αF alone. Thus by full use of the Rheometer data, the extrusion shrinkage or other structure-related properties of carbon black filled stocks can be predicted.

Carbon-Black-Elastomer Interaction

1991 ◽  
Vol 64 (1) ◽  
pp. 19-39 ◽  
Author(s):  
J. A. Ayala ◽  
W. M. Hess ◽  
F. D. Kistler ◽  
G. A. Joyce
Keyword(s):  
Carbon Black ◽  
Surface Activity ◽  
Chemical Reactivity ◽  
Surface Reactivity ◽  
Moisture Adsorption ◽  
Carbon Blacks ◽  
Bound Rubber ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Polymer Interaction

Abstract A number of different techniques were applied to measure carbon-black-surface reactivity and the level of black-polymer interaction in four different elastomer systems (SBR, IIR, NR, and NBR) representing differences in unsaturation, crystallinity and polarity. Known within-grade surface activity variations were based on partial graphitization of an N121-type carbon black. The surface activity of different black grades was studied as a function of variations in both surface area and DBPA. Direct measurements of carbon-black-surface reactivity were based on hydrogen analysis, SIMS, IGC, and moisture adsorption. In-rubber measurements included bound rubber, SIMS of cut surfaces, and an interaction parameter, σ/η, which is derived from the slope (σ) of the stress-strain curve at low elongations, and (η), the ratio of dynamic modulus (E′) at 1% and 25% DSA. The following trends were observed: 1. The σ/η values provided a good measure of black-polymer interaction in all four polymer systems for either the within-grade or across-grade comparisons. 2. Higher σ/η values were indicated for SBR and NBR, followed by NR and IIR in that order. 3. SBR indicated the greatest sensitivity for bound-rubber measurements in terms of distinguishing within-grade variations in black-polymer interaction, followed by IIR, NR, and NBR in that order. 4. Positive SIMS on dry carbon black indicates the presence of complex hydrocarbon structures suitable for chemical reactivity at the carbon-black surface. 5. SIMS analyses on the dry carbon blacks exhibited intensity variations in the negative hydrocarbon fragments which were in line with the within-grade variations in hydrogen content. 6. SIMS analyses on the cut-rubber compound surfaces showed overall variations in intensity which were proportional to the range and level of the bound-rubber measurements. The most meaningful variations were recorded for SBR and IIR. 7. Heats of adsorption derived from IGC measurements with different adsorbates showed an excellent correlation with black-polymer interaction for the within-grade studies. Measurements across grades did not correlate as well with the in-rubber measurements, but the best results were obtained using styrene as the adsorbate. 8. The within-grade moisture adsorption measurements showed excellent agreement with IGC and the other techniques for the N121 series of heat-treated carbon blacks.

Interaction Between Rubber and Carbon Black Studied by ToF-SIMS

2002 ◽  
Vol 75 (4) ◽  
pp. 627-634 ◽  
Author(s):  
P. Bertrand ◽  
L.-T. Weng ◽  
W. Lauer ◽  
R. Zimmer
Keyword(s):  
Carbon Black ◽  
Thin Layer ◽  
Polymer Chain ◽  
Surface Concentration ◽  
Tof Sims ◽  
Bound Rubber ◽  
Polymer Chain Conformation ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Styrene Butadiene

Abstract In order to study the rubber—carbon black filler interaction, different styrene-butadiene rubbers were adsorbed from solution on carbon black. Afterwards, the samples were washed to keep only the thin layer of bound rubber. The surface of these samples was characterized by ToF-SIMS. It was found that the carbon black surface was completely covered by the polymer, except for pure 1,4-polybutadiene where a non-uniform adsorption was seen. Moreover, the ToF-SIMS data showed that the parameters related to the polymer aromaticity and unsaturation decreased after adsorption. These results indicated a change in polymer chain conformation at the surface upon adsorption on carbon black. This was explained by a preferential interaction between phenyl (and in a weaker manner, 1,2-vinyl) groups with the carbon black surface. Indeed, when these groups tend to orientate toward the filler surface, their surface concentration seen by ToF-SIMS is expected to decrease.

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.

scholarly journals Grafting onto carbon black having few functional group 4. Reaction of epoxy resin with imidazoline groups introduced onto carbon black surface.

1991 ◽  
Vol 64 (4) ◽  
pp. 267-274 ◽  
Author(s):  
Norio TSUBOKAWA ◽  
Kazuhito YANADORI ◽  
Yasuo SONE
Keyword(s):  
Carbon Black ◽  
Epoxy Resin ◽  
Functional Group ◽  
Group 4 ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Grafting Onto

scholarly journals Radical Grafting from Carbon Black. Graft Polymerization of Vinyl Monomers Initiated by Peroxyester Groups Introduced onto Carbon Black Surface

1988 ◽  
Vol 20 (3) ◽  
pp. 213-220 ◽  
Author(s):  
Norio Tsubokawa ◽  
Kazuhiro Fujiki ◽  
Yasuo Sone
Keyword(s):  
Carbon Black ◽  
Graft Polymerization ◽  
Vinyl Monomers ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Grafting From

scholarly journals Analysis of Activation Process of Carbon Black Based on Structural Parameters Obtained by XRD Analysis

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 153
Author(s):  
Sang-Min Lee ◽  
Sang-Hye Lee ◽  
Jae-Seung Roh
Keyword(s):  
Carbon Black ◽  
Early Stage ◽  
Structural Parameters ◽  
Xrd Analysis ◽  
Activation Process ◽  
Co2 Gas ◽  
Carbon Black Surface ◽  
Black Surface ◽  
Last Stage ◽  
Pore Properties

In the present study, carbon black activated by CO2 gas was examined through XRD analysis, especially with regard to changes in its structural parameters. Based on the results, its activation process was thoroughly analyzed. The activation process was controlled by isothermally activating the carbon black inside a reaction tube through which CO2 gas flowed. With this approach, the degree of activation was varied as desired. At an early stage of the activation process, the amorphous fraction on the carbon black surface was preferentially activated, and later the less-developed crystalline carbon (LDCC) region inside the carbon black particles started to be activated. The latter process was attributable to the formation of pores inside the carbon black particles. As the activation process proceeded further, the more-developed crystalline carbon (MDCC) region started to be activated, thereby causing the pores inside the carbon black particles to grow larger. At the last stage of the activation process, La was found to be decreased to about 40 Å. This implied that the edges of the graphite crystals had been activated, thus causing the internal pores to grow and coalesce into larger pores. Activated conductive Super-P with enhanced pore properties is expected to have wide applications.

Sign in / Sign up

Export Citation Format

Share Document