Sulfur Vulcanization of Simple Model Olefins Part III: Vulcanization of 2,3-Dimethyl-2-Butene in the Presence of Different Metal Complexes

Abstract The mechanism of the sulfur vulcanization of rubber was studied by using 2,3-dimethyl-2-butene (C6H12) as a simple, low-molecular model alkene. Only equivalent allylic positions are present in this alkene. Treating C6H12 with a mixture of ZnO, S8 and the accelerator tetramethylthiuramdisulfide at 140°C yields a mixture of addition products (C6H11—Sn—C6H11). Similar reactions in the presence of various metal oxides instead of zinc oxide show poor vulcanization results. Experiments with various metal dithiocarbamate complexes show a reactivity towards vulcanization in the following sequence: Zn(detc)2>Cd(detc)2>Cu(detc)2>Pb(detc)2>Zn(dmtc)2>Ni(detc)2>Cu(dmtc)2.

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ZINC OXIDE VERSUS MAGNESIUM OXIDE REVISITED. PART 1

Rubber Chemistry and Technology ◽

10.5254/1.3672428 ◽

2012 ◽

Vol 85 (1) ◽

pp. 38-55 ◽

Cited By ~ 10

Author(s):

Manuel Guzmán ◽

Berta Vega ◽

Núria Agulló ◽

Ulrich Giese ◽

Salvador Borrós

Keyword(s):

Zinc Oxide ◽

Environmental Impact ◽

Natural Rubber ◽

Metal Oxides ◽

Environmental Effects ◽

Model Compound ◽

Rubber Industry ◽

Sulfur Vulcanization ◽

Activator System

Abstract Zinc oxide is a widely used compound in the rubber industry due to the excellent properties that it shows as activator, and consequently, its role in the mechanism of accelerated sulfur vulcanization has been extensively studied. Due to the increased concern about its environmental effects, several research studies have been carried out in order to substitute it with different metal oxides such us MgO. The effect of the activator system in order to minimize the environmental impact of the rubber goods has been explored. The work developed is presented in two parts. In Part 1, the influence of different mixtures of ZnO and MgO on the vulcanization of natural rubber has been investigated. In Part 2, model compound vulcanization has been used to study the role of MgO on the mechanism to gain a better understanding of the differences shown in Part 1.

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ZINC OXIDE VERSUS MAGNESIUM OXIDE REVISITED. PART 2

Rubber Chemistry and Technology ◽

10.5254/1.3672429 ◽

2012 ◽

Vol 85 (1) ◽

pp. 56-67 ◽

Cited By ~ 8

Author(s):

Manuel Guzmán ◽

Berta Vega ◽

Núria Agulló ◽

Salvador Borrós

Keyword(s):

Zinc Oxide ◽

Environmental Impact ◽

Natural Rubber ◽

Metal Oxides ◽

Environmental Effects ◽

Model Compound ◽

Rubber Industry ◽

Sulfur Vulcanization ◽

Activator System

Abstract Zinc oxide is a widely used compound in the rubber industry due to the excellent properties that it shows as an activator and, consequently, its role in the mechanism of accelerated sulfur vulcanization has been extensively studied. Due to the increased concern about its environmental effects, several research studies have been carried out in order to substitute it with different metal oxides such us MgO. The effect of the activator system in order to minimize the environmental impact of the rubber goods has been explored. The work developed is presented in two parts. In Part 1, the influence of different mixtures of ZnO and MgO in the vulcanization of natural rubber has been investigated. In Part 2 of the study, model compound vulcanization has been used to study the role of MgO on the mechanism to gain a better understanding of the differences shown in the first part.

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Sulfur Vulcanization of Simple Model Olefins, Part II: Characterization and Reactivity of Intermediate Vulcanization Products of 2,3-Dimethyl-2-Butene

Rubber Chemistry and Technology ◽

10.5254/1.3538672 ◽

1994 ◽

Vol 67 (2) ◽

pp. 252-262 ◽

Cited By ~ 18

Author(s):

P. Versloot ◽

J. G. Haasnoot ◽

J. Reedijk ◽

M. van Duin ◽

E. F. J. Duynstee ◽

...

Keyword(s):

Simple Model ◽

Molecular Model ◽

Intermediate Products ◽

Unsaturated Rubber ◽

Sulfur Vulcanization

Abstract In a study of the mechanism of the sulfur vulcanization of unsaturated rubber, 2,3-dimethyl-2-butene (C6H12) was used as a simple, low-molecular model alkene. Only equivalent allylic positions are present in this alkene. Treating C6H12 with a mixture of ZnO, S8 and the accelerator tetramethylthiuramdisulflde at 140°C for 20 minutes yields a mixture of addition products (C6H11—Sn—C6H11) and also intermediate products (C6H11—Sn—S(S)CN(CH3)2). The formation of C6H11—Sn—C6H11 from these intermediate products only proceeds in the presence of the zinc dimethyldithiocarbamate complex and free alkene.

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Sulfur Vulcanization of Simple Model Olefins, Part IV: Vulcanizations of 2,3-Dimethyl-2-Butene with TMTD and Activated Zinc Dithiocarbamate/Xanthate Accelerators at Different Temperatures

Rubber Chemistry and Technology ◽

10.5254/1.3538757 ◽

1995 ◽

Vol 68 (4) ◽

pp. 563-572 ◽

Cited By ~ 12

Author(s):

P. Versloot ◽

J. G. Haasnoot ◽

J. Reedijk ◽

M. van Duin ◽

J. Put

Keyword(s):

Simple Model ◽

Room Temperature ◽

Molecular Model ◽

Secondary Amines ◽

Temperature Range ◽

Intermediate Products ◽

Sulfur Vulcanization ◽

Different Temperatures

Abstract The mechanism of the accelerated sulfur vulcanization of rubber was studied by the use of 2,3-dimethyl-2-butene (C6H12, TME) as a simple, low-molecular model alkene. Treatment of TME with a mixture of ZnO, S8 and the classical accelerator TMTD at temperatures above 100°C yields a mixture of addition products ((C6H11—Sn—C6H11) ). In the temperature range of 50 up to 100 °C only intermediate products, C6H11—Sn—S(S)CN(CH3)2 are obtained. Room temperature vulcanization is feasible using highly reactive accelerators, such as xanthate derivatives. These derivatives result in formation of the crosslink precursors which are converted to the actual crosslink in the presence of zinc dithiocarbamates. The addition of (secondary) amines enhances the solubility of the dithiocarbamates, and therefore the reactivity of the xanthate/zinc dithiocarbamate combination.

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Schiff Base Metal Complexes Precursor for Metal Oxide Nanomaterial: A Review

Current Nanoscience ◽

10.2174/1573413716999201127112204 ◽

2020 ◽

Vol 16 ◽

Author(s):

Meghshyam K. Patil ◽

Vijay H. Masand ◽

Atish K. Maldhure

Keyword(s):

Schiff Base ◽

Metal Complexes ◽

Metal Oxides ◽

Base Metal ◽

Carbonyl Compounds ◽

Organic Transformations ◽

Iron Cobalt ◽

Methods Of Synthesis ◽

Schiff Base Metal Complexes ◽

Nickel Manganese

: Schiff bases and their complexes are versatile compounds, which have been synthesized from the condensation of carbonyl compounds with amino compounds and exhibit a broad range of applications in biological, medicinal, catalysis, and industrial purposes. Furthermore, Schiff base-metal complexes have been used as a precursor for the synthesis of different metal oxides, which includes oxides of iron, cobalt, copper, nickel, manganese, vanadium, cadmium, zinc, mercury, etc. and ferrites such as Fe3O4, ZnFe2O4, and ZnCo2O4. These metal oxides have been utilized for several applications, which includes as a catalyst for several organic transformations and for biological activity. This review encompasses different methods of synthesis of metal oxides using Schiff base metal complexes precursor, their characterization, and various applications in detail.

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A critical review of synthesis parameters affecting the properties of zinc oxide nanoparticle and its application in wastewater treatment

Applied Water Science ◽

10.1007/s13201-021-01370-z ◽

2021 ◽

Vol 11 (2) ◽

Author(s):

E. Y. Shaba ◽

J. O. Jacob ◽

J. O. Tijani ◽

M. A. T. Suleiman

Keyword(s):

Zinc Oxide ◽

Metal Oxides ◽

Zinc Oxide Nanoparticles ◽

Textural Properties ◽

Oxide Nanoparticles ◽

Zinc Oxide Nanoparticle ◽

Synthesis Parameters ◽

Metal Precursors ◽

Removal Of Heavy Metals ◽

Oxide Nanoparticle

AbstractIn this era, nanotechnology is gaining enormous popularity due to its ability to reduce metals, metalloids and metal oxides into their nanosize, which essentially alter their physical, chemical, and optical properties. Zinc oxide nanoparticle is one of the most important semiconductor metal oxides with diverse applications in the field of material science. However, several factors, such as pH of the reaction mixture, calcination temperature, reaction time, stirring speed, nature of capping agents, and concentration of metal precursors, greatly affect the properties of the zinc oxide nanoparticles and their applications. This review focuses on the influence of the synthesis parameters on the morphology, mineralogical phase, textural properties, microstructures, and size of the zinc oxide nanoparticles. In addition, the review also examined the application of zinc oxides as nanoadsorbent for the removal of heavy metals from wastewater.

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Effect of Calcination on the Basic Strength of Surface Modified Nano-Zinc Oxide Characterised by FTIR and Back Titration Methods

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1107.326 ◽

2015 ◽

Vol 1107 ◽

pp. 326-332

Author(s):

Abdul Rahim Yacob ◽

Kamaluddeen Suleiman Kabo

Keyword(s):

Zinc Oxide ◽

Metal Oxides ◽

Base Catalysis ◽

Nano Zinc Oxide ◽

Back Titration ◽

And Performance ◽

Nano Zinc ◽

Surface Modified ◽

Heterogeneous Base ◽

Basic Strength

The use of metal oxides in heterogeneous base catalysis has gained a large interest due to their application in many chemical and industrial processes and is environmental friendly. Basic metal oxides are commonly used and their structures, morphology and performance can be modified by method of preparation and thermal activation. In this study, surface modified amphoteric zinc oxide was prepared via hydration-dehydration method and characterised by TGA and FTIR. The basic strength at various temperatures is characterised by FTIR and back titration analyses. The results shows that surface modified zinc oxide has the highest basic strength of 1.453mmolg-1at 400°C making it a relatively good and suitable compound for use in heterogeneous basic catalysis. This result is also supported by FTIR spectra which show possible relationship between the Lewis O2-and increasing basic strength.

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The solubility of transition metal oxides in zinc oxide and the reflectance spectra of Mn2+ and Fe2+ in tetrahedral fields

Journal of Inorganic and Nuclear Chemistry ◽

10.1016/0022-1902(66)80318-4 ◽

1966 ◽

Vol 28 (2) ◽

pp. 397-405 ◽

Cited By ~ 118

Author(s):

C.H. Bates ◽

W.B. White ◽

R. Roy

Keyword(s):

Zinc Oxide ◽

Transition Metal ◽

Metal Oxides ◽

Transition Metal Oxides ◽

Reflectance Spectra

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Effect of Sulfur and Dicumyl Peroxide on Vulcanization of Natural Rubber with Tetramethylthiuram Disulfide and Zinc Oxide

Rubber Chemistry and Technology ◽

10.5254/1.3547330 ◽

1970 ◽

Vol 43 (6) ◽

pp. 1294-1310 ◽

Cited By ~ 9

Author(s):

S. P. Manik ◽

S. Banerjee

Keyword(s):

Zinc Oxide ◽

Stearic Acid ◽

Natural Rubber ◽

Reaction Mechanisms ◽

Elemental Sulfur ◽

Initial Rate ◽

Dicumyl Peroxide ◽

Tetramethylthiuram Disulfide ◽

Sulfur Vulcanization ◽

Salient Features

Abstract The salient features of both non-elemental sulfur vulcanization by TMTD and elemental sulfur vulcanization promoted by TMTD both in presence and absence of ZnO and stearic acid have been studied. TMTD increases the rate of DCP decomposition and lowers the crosslinking maxima due to DCP depending on its concentration. However, with higher amounts of TMTD the initial rate of crosslinking is increased with the increased amount of TMTD, while crosslinking maxima are still lowered due to reversion. ZnO or ZnO-stearic acid, however, seems to alter the entire course of the reaction. Both the crosslink formation and TMTD decomposition are much higher in presence of ZnO or ZnO-stearic acid, but stearic acid seems to have no effect. The reaction mechanisms for TMTD accelerated sulfuration in absence and presence of ZnO have also been studied.

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