The Change in the Crystal Structure of Zinc Oxide in a Binary ε-Caprolactam–Stearic Acid Melt

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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Studies on Dicumyl Peroxide Vulcanization of Styrene—Butadiene Rubber in Presence of Sulfur and 2-Mercaptobenzothiazole

Rubber Chemistry and Technology ◽

10.5254/1.3540436 ◽

1974 ◽

Vol 47 (2) ◽

pp. 266-281 ◽

Cited By ~ 3

Author(s):

C. K. Das ◽

S. Banerjee

Keyword(s):

Zinc Oxide ◽

Stearic Acid ◽

Crosslink Density ◽

Addition Reaction ◽

Styrene Butadiene Rubber ◽

Methyl Groups ◽

Butadiene Rubber ◽

First Order ◽

First Order Kinetics ◽

Styrene Butadiene

Abstract The effect of sulfur, MBT, zinc oxide, and stearic acid on the DCP vulcanization of SBR has been studied. DCP decomposition obeys first order kinetics in all cases, but its rate constant is higher in presence of MBT. Sulfur and MBT reduce the crosslink density due to DCP. In the mixes containing sulfur, MBT, zinc oxide, and stearic acid in presence of DCP the crosslink density is initially additive. Here oxidation of some pendent vinyl groups are effected by DCP, and these groups also take part in thiol addition reaction with MBT. The thiazole accelerated sulfuration of SBR proceeds fundamentally by the same mechanism as reported for NR, but the details show slight difference chiefly due to the presence of pendent vinyl groups and styrene units in the chain and due to the absence of pendent methyl groups in SBR.

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Preparation of Layered Potassium Titanate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1463 ◽

2008 ◽

Vol 368-372 ◽

pp. 1463-1464 ◽

Cited By ~ 1

Author(s):

Lu Ting Yan ◽

Wen Jie Si ◽

Feng Teng ◽

Yan Peng Zheng ◽

Chun Ai Dai

Keyword(s):

Crystal Structure ◽

High Temperature ◽

Solid State ◽

Stearic Acid ◽

Solid State Reaction ◽

Potassium Titanate ◽

Important Intermediate

Layered potassium titanate is an important intermediate in preparing titania nanosheets. Three methods including method of potassium stearate, method of stearic acid and method of high-temperature solid-state reaction were used to produce layered potassium titanate in this paper. XRD and SEM were used to characterize the crystal structure and shape. The result of experiments showed that method of potassium stearate was the most effective way to prepare the layered potassium titanate.

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Confocal Raman imaging, FTIR spectroscopy and kinetic modelling of the zinc oxide/stearic acid reaction in a vulcanizing rubber

Polymer ◽

10.1016/j.polymer.2012.12.021 ◽

2013 ◽

Vol 54 (2) ◽

pp. 685-693 ◽

Cited By ~ 12

Author(s):

Pellegrino Musto ◽

Domenico Larobina ◽

Salvatore Cotugno ◽

Paolo Straffi ◽

Giuseppe Di Florio ◽

...

Keyword(s):

Zinc Oxide ◽

Stearic Acid ◽

Ftir Spectroscopy ◽

Kinetic Modelling ◽

Raman Imaging ◽

Acid Reaction ◽

Confocal Raman

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Effect of the ligand in the crystal structure of zinc oxide: an x-ray powder diffraction, x-ray absorption near-edge structure, and an extended x-ray absorption fine structure study

MRS Communications ◽

10.1557/mrc.2016.14 ◽

2016 ◽

Vol 6 (2) ◽

pp. 93-97

Author(s):

María de los A. Cepeda-Pérez ◽

Cristina M. Reyes-Marte ◽

Valerie Ann Carrasquillo ◽

William A. Muñiz ◽

Edgar J. Trujillo ◽

...

Keyword(s):

Crystal Structure ◽

Zinc Oxide ◽

Fine Structure ◽

Powder Diffraction ◽

Structure Study ◽

Edge Structure ◽

X Ray ◽

Absorption Fine ◽

Image Position ◽

X Ray Absorption

Abstract

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Correlation between Microstructure and Chemical Composition of Zinc Oxide Gas Sensor Layers and Their Gas-Sensitive Properties in Chlorine Atmosphere

10.20944/preprints202011.0378.v1 ◽

2020 ◽

Author(s):

Marta Fiedot-Toboła ◽

Patrycja Suchorska-Woźniak ◽

Kamila Startek ◽

Olga Rac-Rumijowska ◽

Monika Kwoka ◽

...

Keyword(s):

Crystal Structure ◽

Zinc Oxide ◽

Chemical Composition ◽

Specific Surface ◽

Gas Sensor ◽

Photoelectron Spectroscopy ◽

Structural Defects ◽

X Ray ◽

Conductance Method ◽

The Impact

In the article we present the results concerning the impact of structural and chemical properties of zinc oxide in various morphological forms, on its gas-sensitive properties tested in an atmosphere containing a very aggressive gas such as chlorine. Two types of ZnO sensor layers obtained by two different technological methods were used. Their morphology, crystal structure, specific surface area, porosity, surface chemistry and structural defects were characterized, and then compared with gas-sensitive properties in a chlorine-containing atmosphere. To achieve this goal scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL) methods were used. The sensing properties of obtained active layers were tested by temperature stimulated conductance method (TSC). We have noticed that their response in chlorine atmosphere is not determined by the size of the specific surface or porosity. The obtained results showed that the structural defects of ZnO crystals play the most important role in chlorine detection. We demonstrated that the Cl2 adsorption is a concurrent process to oxygen adsorption. Both of them occur on the same active species (oxygen vacancies). They concentration is higher on the side planes of the zinc oxide crystal than the others. Thanks to the conducted studies authors demonstrated that to develop a new gas sensor devices not only changing of active layer chemical composition but also controlling its crystal structure and morphology could be used.

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Processing and characterization of natural rubber/stearic acid-tetra-needle-like zinc oxide whiskers medical antibacterial composites

Journal of Polymer Research ◽

10.1007/s10965-017-1433-y ◽

2018 ◽

Vol 25 (2) ◽

Cited By ~ 6

Author(s):

Xi Chen ◽

Zhifen Wang ◽

Jie Wu

Keyword(s):

Zinc Oxide ◽

Stearic Acid ◽

Natural Rubber

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Preparation and Characterization of Waterborne UV Lacquer Product Modified by Zinc Oxide with Flower Shape

Polymers ◽

10.3390/polym12030668 ◽

2020 ◽

Vol 12 (3) ◽

pp. 668 ◽

Cited By ~ 2

Author(s):

Yan Wu ◽

Xinyu Wu ◽

Feng Yang ◽

Jiaoyou Ye

Keyword(s):

Zinc Oxide ◽

Stearic Acid ◽

Erosion Resistance ◽

Hydrophobic Surface ◽

Zinc Stearate ◽

Raw Material ◽

Hydroxyl Group ◽

Vapor Molecule ◽

Poplar Wood ◽

Acid Vapor

In this paper, the waterborne UV lacquer product (WUV) was used as the main raw material, zinc oxide (ZnO) was used as the additive, and the stearic acid as the surface modifier. According to the method of spraying coating on the surface of poplar wood (Populus tomentosa), a simple and efficient preparation method was carried out to generate a super-hydrophobic surface and enhance the erosion resistance of the coating. By testing, the contact angle (CA) of water on the coating surface can reach 158.4°. The microstructure and chemical composition of the surface of coatings were studied by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The results showed that under acidic conditions, the non-polar long chain alkyl group of stearic acid vapor molecule reacted with the hydroxyl group in acetic acid, the metal ions of the ZnO were displaced to the stearic acid and generated globular zinc stearate (C36H70O4Zn). The hydrophobic groups –CH3 were grafted to the surface of zinc stearate (ZnSt2) particles and the micro/nano level of multistage flower zinc stearate coarse structure was successfully constructed on the surface of poplar wood, which endowed it with superhydrophobic properties. It is shown that the coating has good waterproof and erosion resistance.

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