THERMOREVERSIBLE CROSS-LINKING OF RUBBER COMPOUNDS: FROM PROOF-OF-CONCEPT TOWARD AN INDUSTRIAL PROCESS

2018 ◽  
Vol 91 (2) ◽  
pp. 492-508 ◽  
Author(s):  
L. M. Polgar ◽  
J. Keizer ◽  
R. Blom ◽  
B. Niemeijer ◽  
T. de With ◽  
...  
Keyword(s):  
Carbon Black ◽  
Material Properties ◽  
Industrial Process ◽  
Mineral Oil ◽  
Diels Alder ◽  
Cross Linking ◽  
Proof Of Concept ◽  
Rubber Compounds ◽  
Internal Mixer ◽  
Batch Mixer

ABSTRACT It is demonstrated that the concept of thermoreversible cross-linking of functionalized maleic anhydride grafted ethylene–propylene (EPM-g-MA) rubber using Diels–Alder chemistry is limited neither to laboratory scale using a solvent route nor to gum rubber. The use of an internal mixer is the first step toward an industrial process, since it greatly reduces the processing time and allows for a solventless process for the furan-functionalization and subsequent bismaleimide cross-linking of EPM rubber. Practical rubber compounds were prepared by mixing thermoreversibly cross-linked EPM with carbon black and mineral oil in the same batch mixer. This resulted in reinforcement of the rubber without affecting the thermoreversible character of the cross-linking. The pendant furan groups of the (non)cross-linked EPM-g-furan interact with the carbon black filler. Finally, crystalline EPM rubber compounds were prepared, which show excellent material properties and property retention over multiple reprocessing cycles.

Online Method for Characterization of the Homogeneity of Rubber Compounds Filled with Non-Conductive Carbon Black

2006 ◽  
Vol 79 (4) ◽  
pp. 610-620 ◽  
Author(s):  
H. H. Le ◽  
M. Tiwari ◽  
S. Ilisch ◽  
H-J. Radusch
Keyword(s):  
Carbon Black ◽  
Electrical Conductance ◽  
Rubber Compound ◽  
Mixture Ratio ◽  
Dispersion Process ◽  
Filled Rubber ◽  
Rubber Compounds ◽  
Conductance Method ◽  
Internal Mixer

Abstract In the present work, the effect of carbon black (CB) type on the electrical conductance of CB filled rubber compounds measured online in the internal mixer and the corresponding CB dispersion were investigated. The CB dispersion is strongly affected by the specific surface area and structure of CB which can be directly monitored by use of the online electrical conductance method. The effect of CB mixture ratio of a high conductive CB and a non-conductive one on the online electrical conductance was investigated for CB filled rubber compounds. By addition of a small amount of a high-conductive CB type into a non-conductive CB filled rubber compound, a characteristic online conductance - time characteristic is observed that is a result of the formation of a joint network of the two CB types. It could be shown, that such a characteristic is suitable to monitor the dispersion process of the non-conductive CB in the rubber compound.

RECYCLING BEHAVIOR OF THERMOREVERSIBLY DIELS–ALDER CROSSLINKED EPM

2021 ◽  
Author(s):  
Alexander T. Zdvizhkov ◽  
Martin Van Duin ◽  
Francesco Picchioni
Keyword(s):  
Carbon Black ◽  
Mechanical Strength ◽  
Air Flow ◽  
Negative Influence ◽  
Antioxidant Effect ◽  
Diels Alder ◽  
Rubber Compounds ◽  
Recycling Behavior

ABSTRACT The recyclability of thermoreversibly Diels–Alder (DA) crosslinked EPM has been studied. The retro DA reaction dominates over the dehydration–aromatization process of the DA adduct. Moreover, a negative influence of air occurred as a result of a crosslinking in air flow. Nevertheless, rubber compounds prepared from EPM-g-furan and carbon black can be recycled several times without losing mechanical strength, a feature attributed to a strong antioxidant effect of the carbon black.

Oxidation of Unvulcanized Cold Rubber Influence of Adsorption by Carbon Black

1952 ◽  
Vol 25 (3) ◽  
pp. 557-572
Author(s):  
C. W. Sweitzer ◽  
Francis Lyon
Keyword(s):  
Carbon Black ◽  
Surface Chemistry ◽  
Carbon Films ◽  
Cross Linking ◽  
Additional Information ◽  
Rubber Compounds ◽  
Repressive Effect ◽  
Solvent Systems ◽  
Dilute System

Abstract Previous investigations have shown a large difference between the amount of rubber insolubilized by carbon black in dilute solvent systems and in standard mill mixes. The purpose of this study, after reconciling these extremes, was to evaluate the role of adsorption in the insolubilization of rubber in mill-mixed compounds. An adsorption test was employed which eliminated the solvent effect of the dilute system and the mastication effect in mill mixing. Results showed that carbon black, depending on the temperature and atmosphere conditions imposed on the rubber carbon films, represses the scission, cross-linking, and gelation reactions of GR-S X-478. This repressive effect is ascribed to the adsorption and inactivation by the carbon black of the oxidized intermediates through which these various reactions proceed. The magnitude of this effect was found to vary with the type, loading, and surface chemistry of the carbon. This approach not only offers promise as a means for predicting the behavior of carbon black in rubber compounds, but also, because of its applicability to the study of all rubber-carbon systems, offers possibilities of providing additional information on the mechanism of the carbon-rubber bond.

Moisture Effects on TESPD-Silica/CB/SBR Compounds

2005 ◽  
Vol 78 (1) ◽  
pp. 84-104 ◽  
Author(s):  
Kwang-Jea Kim ◽  
John VanderKooi
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Silica Surface ◽  
Cross Linking ◽  
Water Molecules ◽  
Cure Rate ◽  
Moisture Effects ◽  
Mooney Viscosity ◽  
Heat Build Up ◽  
Internal Mixer

Abstract Moisture was treated on a silica surface and it was added into bis(triethoxysilylpropyl)disulfide (TESPD)/carbon black (CB)/S-SBR compound and mixed in an internal mixer. The effects of moisture were investigated with respect to the temperature rise during mixing, processability, cure characteristics, and mechanical properties and two-pass (2P) mixings were compared with conventional three-pass (3P) mixings. Addition of the moisture treated silica into the compound lowered the heat generation during mixing, lowered the drop temperature, decreased the scorch time, lowered the heat build up, lowered the tanδ (E″/E′), increased the Mooney viscosity, increased the torque rise (MH-ML), increased the elongation modulus, increased the blow out time, and increased the deformation%. The properties of each compound were gradually increased with the level of moisture and the 2P mixing procedure generated less heat during mixing and exhibited better mechanical properties than the 3P mixing one. The addition of water molecules improved the silane reaction with silica surface via improved hydrolysis and resulted in an increased level of cross-linking. It also seemed hydrolyzes the benzothiazolesulfenamide accelerator and resulted in a faster scorch and an increased cure rate.

Online Characterization of the Effect of Mixing Parameters on Carbon Black Dispersion in Rubber Compounds Using Electrical Conductivity

2004 ◽  
Vol 77 (1) ◽  
pp. 147-160 ◽  
Author(s):  
H. H. Le ◽  
S. Ilisch ◽  
B. Jakob ◽  
H.-J. Radusch
Keyword(s):  
Electrical Conductivity ◽  
Carbon Black ◽  
Mixing Parameters ◽  
Rubber Compounds ◽  
Mixing Regime ◽  
Internal Mixer ◽  
Optimal Mixing ◽  
Insight Into ◽  
Carbon Black Dispersion

Abstract The influences of mixing parameters on the carbon black dispersion can be characterized using the electrical conductivity online measured from internal mixer. As a measure for monitoring the development of carbon black dispersion, a normalized conductivity with regard to the conductivity measured at the BIT (black incorporation time) has been suggested. It is observed that in spite of different mixing parameters, the mixtures possessing the same normalized conductivity factor K/KBIT deliver the same carbon black dispersion and the same mechanical properties. Based on normalized conductivity, a deeper insight into the mixing kinetics can be provided to find an optimal mixing regime.

scholarly journals The Use of Copper Oxides as Cross-Linking Substances for Chloroprene Rubber and Study of the Vulcanizates Properties. Part II. The Effect of Filler Type on the Properties of CR Products

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6528
Author(s):  
Aleksandra Smejda-Krzewicka ◽  
Piotr Kobędza ◽  
Krzyssztof Strzelec ◽  
Agnieszka Adamus-Włodarczyk
Keyword(s):  
Carbon Black ◽  
Oxygen Index ◽  
Copper Oxides ◽  
Cross Linking ◽  
Curing Agent ◽  
Rubber Compounds ◽  
Curing Characteristics ◽  
Chloroprene Rubber ◽  
Dynamical Properties ◽  
The Cross

The properties of rubber materials are dependent on the characteristics of the elastomer matrix, the filler type, the cross-linking agent, the number of ingredients, and their interactions. In the previous article, we showed that chloroprene rubber can be efficiently cross-linked with copper(I) oxide or copper(II) oxide. During the processing of rubber compounds, the incorporation of a filler and a curing substance are two substantial parameters, such as the homogeneity of mixing and cross-linking that significantly affect the properties of the vulcanizates. Therefore, this work aimed to evaluate the curing characteristics, mechanical and dynamical properties, morphology, and flammability of the composites containing chloroprene rubber cross-linked with Cu2O or CuO and filled with different fillers (silica, carbon black, montmorillonite, kaolin, chalk). It was found that the type of filler and curing agent had a significant impact on the degree of cross-linking of the chloroprene rubber and the properties of its vulcanizates. The degree and speed of the cross-linking of filled CR were higher when the CR was cured with copper(II) oxide. Among the fillers used, the presence of carbon black or silica ensured the highest degree of CR cross-linking and the most useful properties. The flammability tests indicated that all produced vulcanizates were characterized by a high oxygen index, which allows them to be classified as non-flammable materials.

RHEOLOGICAL BEHAVIOR AND MECHANICAL PROPERTIES OF RUBBER COMPOSITES BASED ON NATURAL RUBBER LOADED WITH MINERAL OILS AND PYROLYTIC CARBON BLACK

2021 ◽  
Author(s):  
Sonja Stojanov ◽  
◽  
Mirjana Jovičić ◽  
Ilija Bobinac ◽  
Olga Govedarica ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
Natural Rubber ◽  
Physical Adsorption ◽  
Pyrolytic Carbon ◽  
Mineral Oil ◽  
Slight Reduction ◽  
Physical Interaction ◽  
Waste Products ◽  
Rubber Compounds

This paper aims to investigate the effect of the addition of mineral oil and pyrolytic carbon black on crosslinking the natural rubber and the mechanical properties of the crosslinked products. A rheometer determined curing characteristics at a temperature of 150 °C. The mechanical properties of prepared vulcanized composites were determined. By adding mineral oil to rubber compounds, the vulcanization reaction starts later, and it takes slightly more time to achieve the optimal vulcanization time. The addition of mineral oil to the rubber mixture achieves better dispersion of pyrolytic carbon blacks in the matrix and thus increases the physical interaction between the filler and rubber. Pyrolytic carbon black (pCB) is obtained by recycling waste products and contains a higher proportion of impurities. Due to impurities, PCB has a smaller surface area for the physical adsorption of rubber molecules than standard carbon black, and it can be assumed that this has led to a decrease in the crosslinking density. The addition of mineral oil to rubber compounds results in a slight reduction in mechanical properties. The type of carbon black has a much more significant influence on the mechanical properties of vulcanized composites based on natural rubber.

An Investigation of the Effect of Taurit Filling of Rubber Mixes for the Coating of Radial Lorry Tyre Breakers

2017 ◽  
Vol 44 (11) ◽  
pp. 21-24
Author(s):  
R.R. Mindubaev ◽  
A.M. Mokhnatkin ◽  
V.P. Dorozhkin ◽  
E.G. Mokhnatkina
Keyword(s):  
Carbon Black ◽  
Particle Distribution ◽  
Elastic Recovery ◽  
Dynamic Strength ◽  
Carbon Black Particle ◽  
Test Results ◽  
Rubber Compound ◽  
Rubber Compounds ◽  
Black Particle ◽  
Internal Mixer

The results of investigating the effect of the shungite analogue Taurit (grade TSD) on the properties (measured on an RPA 2000 instrument) of a breaker rubber mix and of a rubber compound based on synthetic isoprene rubber SKI-3 are set out. Different methods of introducing Taurit have been tested: 10 parts into the rubber at the stage of its production; 10 parts into the standard rubber mix at the first stage of mixing; 10 parts into the rubber subjected to preliminary mechanical plasticisation in a laboratory internal mixer at a temperature of 100°C. The introduction of Taurit into the rubber in small quantities in order to reduce the proportion of rubber constituent in the rubber mix has also been tested. The test results have been compared with results for standard rubber mixes and rubber compounds. When Taurit is introduced into rubber at the stage of its production, the cohesive strength of the rubber mix and the rate of its vulcanisation and also the dynamic modulus components G′ and G″ are increased. When Taurit is introduced into plasticised rubber, again G′ and G″ are increased, there is an increase in plasticity, and the elastic recovery of the rubber mix is reduced. The breaker rubber compound from this mix has the best adhesion to metal cord and the highest dynamic strength. Data on the Payne effect indicate a better carbon black particle distribution when Taurit is introduced into the rubber at the stage of its production. Reduction in the proportion of rubber constituent in the rubber mix leads to a deterioration in the carbon black particle distribution.

Study on the Effect of the Temperature Rise of Rubber Compound on Tread Rubber Quality during Mixing Process

2013 ◽  
Vol 750-752 ◽  
pp. 806-810
Author(s):  
Ke Juan Chen ◽  
Sha Xu ◽  
Da Liang Xu
Keyword(s):  
Carbon Black ◽  
Temperature Rise ◽  
Process Condition ◽  
Process Conditions ◽  
Rubber Compound ◽  
Rotor Speed ◽  
Two Stage ◽  
Rubber Compounds ◽  
Mooney Viscosity ◽  
Internal Mixer

With the method of two-stage mixing, two different tread rubbers have been mixed in internal mixer under the different process conditions. After the experiments, test the temperature rise of rubber compound, mooney viscosity and carbon black disperisity. Study the effect of process condition change on the temperature rise of two kinds of rubber compounds and analyze the relationships between the rubber temperature rise and mooney viscosity, carbon black dispersity. The study finds that the temperature rise of rubber compound has a relationship with the rotor speed of internal mixer, rubber viscosity and filling factors, but when the temperature rise of rubber compound is steady, the carbon black dispersity of rubber compound also can be steady. After two-stage mixing, carbon black dispersity of rubber compounds have been improved obviously. These results also imply that rotor speed of internal mixer and filling factor are very important to carbon black dispersity of rubber compounds.

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