Rubber Chemicals from Cyclic Amines. II Dithioamines and Sulfenamides as Accelerators and Curing Agents

1968 ◽  
Vol 41 (3) ◽  
pp. 721-735 ◽  
Author(s):  
Eiichi Morita ◽  
John J. D'Amico ◽  
Evan J. Young
Keyword(s):  
Thermal Analyses ◽  
Empirical Relation ◽  
Basic Structure ◽  
Cure Rate ◽  
Structural Variations ◽  
Cyclic Amine ◽  
Cure Characteristics ◽  
Cyclic Amines ◽  
Curing Agents ◽  
Derivatives Of

Abstract Dithioamines and sulfenamides derived from various cyclic amines were evaluated as accelerators and vulcanizing agents. Structural variations of these compounds are correlated with their scorch delaying properties, accelerating activity and vulcanization efficiency, employing the Mooney Viscometer and the Monsanto Oscillating Disk Rheometer. The relative cure characteristics differed with changes in the basic structure of the compounds, and with the size and type of the cyclic amine moiety. However, the piperidine derivatives consistently showed longer scorch delay and slower mean cure rate than the corresponding derivatives of pyrrolidine, hexamethylenimine or heptamethylenimine. In the case of the thiazolyl sulfenamides, the type of substitution in the thiazolyl group also influenced scorch delay. An empirical relation was observed between the effect of concentration of the thiazolyl sulfenamides on scorch delay and the results of differential thermal analyses of sulfenamide and sulfur blends.

Rubber Chemicals from Cyclic Amines. IV. Thiocarbamyl Amine Disulfide Curing Agents

1971 ◽  
Vol 44 (4) ◽  
pp. 881-888 ◽  
Author(s):  
E. Morita ◽  
J. J. D'Amico
Keyword(s):  
Crosslink Density ◽  
Cure Rate ◽  
Cyclic Amines ◽  
Curing Agents

Abstract The cure properties of thiocarbamyl amine disulfide (I) as vulcanizing agents are influenced by the ionic and steric nature of both R and R′. The relative effects of various R and R′ are analogous to those of R and R′ in thiuram disulfides and dithioamines, respectively. However, the cure properties of I are dominated by the type of R rather than R′. Among the types of R investigated relatively longer scorch delay, slower cure rate and lower crosslink density are obtained, when R is morpholino or 3-azabicyclo(3.2.2)non-3-yl.

Rubber Chemicals from Cyclic Amines. III. Iminocarbodithioates as Accelerators and Curing Agents

1968 ◽  
Vol 41 (3) ◽  
pp. 736-751
Author(s):  
Eiichi Mortia ◽  
John J. D'Amico ◽  
Evan J. Young
Keyword(s):  
Chemical Structure ◽  
Ring Size ◽  
Cure Characteristics ◽  
Cyclic Amines ◽  
Curing Agents ◽  
Kinetics Of ◽  
Kinetics Of Vulcanization

Abstract Evaluations of cyclic iminocarbodithioates as accelerators and vulcanizing agents are described. The starting amines include morpholine and 3-azabicyclo-[3.2.2]nonane and vary in ring size from tetra- to octamethylenimine. The chemical structure of these compounds is correlated with their cure characteristics and the kinetics of vulcanization. Basicity and ring size of the amine moiety govern the activity of the iminocarbodithioates.

Bicyclization of aza-compounds by positive halide ions. I. Cyclic amines

1985 ◽  
Vol 63 (6) ◽  
pp. 1170-1172 ◽  
Author(s):  
R. M. Elofson ◽  
F. F. Gadallah ◽  
J. K. Laidler
Keyword(s):  
Electrochemical Oxidation ◽  
Halide Ions ◽  
Cyclic Amine ◽  
Reaction Conditions ◽  
Specific Reaction ◽  
Cyclic Amines ◽  
Bicyclic Compounds

Cyclic amines are oxidized to the bicyclic compounds by electrochemical oxidation. The presence of halide ions is found necessary for the reaction to proceed and to produce any bicyclic products. It is postulated that a positive halide species, X(+), is produced electrochemically and stabilized under the specific reaction conditions. The X(+) ion forms a complex with the parent cyclic amine which decomposes to the bicyclic product and HX. An analogy between the Hofer–Moest reaction to produce C(+) and this reaction to produce X(+) is postulated

Synthesis and spreading behaviour of some reactive derivatives of long-chain alcohols and carboxylic acids

1984 ◽  
Vol 62 (3) ◽  
pp. 574-579 ◽  
Author(s):  
David A. Holden
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Surface Activity ◽  
Azo Compounds ◽  
Single Chain ◽  
Bulk Solid ◽  
Potential Applications ◽  
Curing Agents ◽  
Derivatives Of ◽  
Long Chain

Procedures are described for the synthesis of several azides, diimides, and azodiformates from long-chain alcohols and fatty acids. These reactive compounds have potential applications as thermal and photochemical curing agents, and as surface-modifying agents for the preparation of filled plastics and chromatographic packings. The surface activity of the compounds was characterized by investigations of their spreading behaviour in monolayers on water. Unlike the single-chain azides and azo compounds, which give well-defined monolayers at all temperatures, monolayers of diacyl diimides and dialkyl azodiformates with two long-chain substituents are unstable with respect to collapse to the bulk solid. The photoreaction of monolayers of octadecanoyl azide to give a mixture of products derived from an intermediate isocyanate was demonstrated by ir and mass spectrometry.

scholarly journals Photochemical rearrangements of substituted thiochromanone sulfoxides

1976 ◽  
Vol 54 (3) ◽  
pp. 455-470 ◽  
Author(s):  
I. W. J. Still ◽  
P. C. Arora ◽  
M. S. Chauhan ◽  
M.-H. Kwan ◽  
M. T. Thomas
Keyword(s):  
Reaction Mechanisms ◽  
Hydrogen Abstraction ◽  
Structural Variations ◽  
Photochemical Behavior ◽  
Photochemical Rearrangements ◽  
Derivatives Of

The photochemical behavior of a number of substituted derivatives of thiochroman-4-one 1-oxide has been examined. In contrast to the analogous sulfones these sulfoxides undergo a variety of photochemical rearrangements. At least three distinct pathways have been recognized; β-hydrogen abstraction or rearrangement to cyclic sulfenates, which then undergo further reaction by homolysis of the S—O bond, appearing to be particularly favorable processes. In a small number of examples, photochemical deoxygenation is observed as a competing reaction. Mechanisms which attempt to account for the influence of structural variations on the particular pathway followed have been proposed.

Synthesis of amino derivatives of caranol by the addition of cyclic amines to 3-carene oxides

1992 ◽  
Vol 28 (2) ◽  
pp. 173-177 ◽  
Author(s):  
I. V. Fedyunina ◽  
V. V. Plemenkov ◽  
G. Sh. Bikbulatova ◽  
L. E. Nikitina ◽  
I. A. Litvinov ◽  
...  
Keyword(s):  
Cyclic Amines ◽  
Amino Derivatives ◽  
Derivatives Of

New Accelerators for Vulcanization of Rubber—Part III: Synthesis, Characterization, and Evaluation of Some 2-Mercaptobenzimidazole Derivatives

1985 ◽  
Vol 58 (4) ◽  
pp. 713-727 ◽  
Author(s):  
D. Pal ◽  
A. Khamrai ◽  
B. Adhikari ◽  
T. Dutta ◽  
Mrinal M. Maiti ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Antioxidant Properties ◽  
Antioxidant Compounds ◽  
Dual Function ◽  
Cure Characteristics ◽  
Aging Resistance ◽  
Rubber Part ◽  
Derivatives Of ◽  
Better Than

Abstract Five derivatives of 2-mercaptobenzimidazole containing S—N bonds have been synthesized and evaluated for their action as accelerator-antioxidant in NR gum stocks. All these compounds exhibit varying degree of accelerating efficiency; some of them, viz. MBSTP, MBSPT, and MBDSPT, offer excellent cure characteristics and vulcanizate properties comparable to some of the best commercially available curatives such as CPTD. Substitution at the N or S atom of the MB molecule does not affect adversely its antioxidant properties; rather, an improvement in aging resistance has been achieved. The degree and nature of substitution play an important role in the antioxidation properties of these MB derivatives. Thus, disubstitution offers better antioxidation characteristics than monosubstitution, and the latter, in turn, is better than unsubstituted MB. Some discussion on correlation of reactivities of these MB derivatives and their cure synergism with CPTD have been reported. It was observed that these new accelerator—antioxidant compounds show very little cure synergism with CPTD but do show promise as dual-function curatives for natural rubber.

Amine Structure-Foam Behavior Relationship and Its Predictive Foam Model Used for Amine Selection for Design of Amine-based Carbon Dioxide (CO2) Capture Process

2020 ◽  
Vol 1 (1) ◽  
pp. 43-57
Author(s):  
Pailin Muchan ◽  
Jessica Narku-Tetteh ◽  
Teeradet Supap ◽  
Raphael Idem
Keyword(s):  
Surface Tension ◽  
Model Development ◽  
Foam Formation ◽  
Plant Design ◽  
Structural Variations ◽  
Capture Process ◽  
Foam Volume ◽  
Cyclic Amines ◽  
Amine Solution ◽  
Foam Model

Background: The use of an amine solution to capture CO2 from flue gases is one of the methods applied commercially to clean up the exhaust gas stream of a power plant. One of the issues in this process is foaming which should be known in order to select a suitable amine for design. Objectives: In this work, all possible types of amines used for CO2 capture, namely, alkanolamines, sterically hindered alkanolamines, multi-alkylamines and cyclic amines, were investigated to elucidate their chemical structure–foaming relationships. Methods: Foam volume produced by each type of 2M amine solution with its equilibrium CO2 loading was measured at 40°C using 94 mL/min of N2 flow. Results: Amines with a higher number or a longer chain of the alkyl group exhibited higher foam volume because of alkyl group’s ability to decrease the surface tension while increasing the viscosity of the solution. An increase in the number of hydroxyl or amino groups in the amine led to the reduction of foam formation due to the increase in surface tension and a decrease in viscosity of the solution. The predictive foam models for non-cyclic and cyclic-amines developed based on the structural variations, surface tension and viscosity of 29 amines predicted the foam volume very well with average absolute deviations (AAD) of 12.7 and 0.001%, respectively. The model accurately predicted the foam volume of BDEA, which was not used in model development with 13.3 %AD. Conclusion: This foam model is, therefore, indispensable in selecting a suitable amine for an amine-based CO2 capture plant design and operation.

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