ChemInform Abstract: Activated Alumina Balls under Neat Conditions: A Green Catalyst for the Synthesis of Spiro-Heterocyclic Scaffolds by Ring-Opening versus Annulation of the Isatin Moiety.

ChemInform ◽  
2016 ◽  
Vol 47 (31) ◽  
Author(s):  
Animesh Mondal ◽  
Biplab Banerjee ◽  
Asim Bhaumik ◽  
Chhanda Mukhopadhyay
Keyword(s):  
Ring Opening ◽  
Activated Alumina ◽  
Green Catalyst

Synthesis and characterization of polyvinylmethylsiloxanes by cationic polymerization using a solid green catalyst

e-Polymers ◽  
2017 ◽  
Vol 17 (5) ◽  
pp. 439-448 ◽  
Author(s):  
Djamal Eddine Kherroub ◽  
Mohammed Belbachir ◽  
Saad Lamouri
Keyword(s):  
Ring Opening ◽  
Polymeric Materials ◽  
Synthesis And Characterization ◽  
Green Catalyst ◽  
Characterization Methods ◽  
H Nmr ◽  
New Strategy ◽  
Cationic Ring Opening Polymerization ◽  
C Nmr

AbstractThe present work is devoted to the synthesis and characterization of vinylsiloxane polymers produced by the use of an activated natural catalyst known as Maghnite-H+. The cationic ring opening polymerization of pentavinylpentamethylcyclopentasiloxane (V5D5) made it possible to obtain the desired polymeric materials. Through this study, we have adapted a new strategy of synthesis of a siloxane polymer with relatively high molecular mass, using a solid initiator activated by sulfuric acid, which has enabled us to combine the ecological aspect of synthesis and the effectiveness of the catalyst in this kind of reaction. Structural [infrared (IR), proton and carbon nuclear magnetic resonance (1H NMR and 13C NMR)], thermal differential scanning (DSC) and chromatographic (GPC) characterization methods have allowed the products obtained to be identified and their various properties to be focused on. The kinetic study was made to determine the order of the reaction. The proposed reaction mechanism shows the advantages of Maghnite-H+.

CuO Nanoparticles as a Simple and Efficient Green Catalyst for the Aziridine Ring‐Opening: Examination of a Broad Range of Nucleophiles

2020 ◽  
Vol 5 (15) ◽  
pp. 4525-4529
Author(s):  
Rana Chatterjee ◽  
Sougata Santra ◽  
Nirnita Chakraborty Ghosal ◽  
Kousik Giri ◽  
Grigory V. Zyryanov ◽  
...  
Keyword(s):  
Ring Opening ◽  
Cuo Nanoparticles ◽  
Aziridine Ring ◽  
Green Catalyst

scholarly journals Synthesis of bio-based poly limonene oxide with green catalyst

2021 ◽  
pp. 271-280 ◽  
Author(s):  
Chahrazed Bendiabdallah ◽  
Fatiha Reguieg ◽  
Mohammed Belbachir
Keyword(s):  
Reaction Time ◽  
1H Nmr ◽  
Ring Opening ◽  
Ring Opening Polymerization ◽  
Green Catalyst ◽  
Sheet Silicate ◽  
Silicate Clay ◽  
Limonene Oxide ◽  
Cationic Ring Opening Polymerization

In the present work, the polymerization of limonene oxide (LO) catalyzed by Maghnite H+ (Mag- H+) is investigated. Mag-H+ is Algerian montmorillonite sheet silicate clay exchanged with protons. The poly limonene oxide (PLO) is obtained by cationic ring opening polymerization in bulk and with solvent. The effect of the reaction time, the temperature and the amount of catalyst are studied and discussed in order to find the optimal reactions conditions. The polymerization in solution at 0 °C with 5% by weight of catalyst leads to the best yield 61.34% for a reaction time of 1h. The structure of the obtained products is characterized by XRD, 1H-NMR, 13C-RMN, ATR-FTIR, DSC and TGA.

scholarly journals A new approach for the polymerization of tetraphenyltetramethylcyclotetrasiloxane by an environmentally friendly catalyst called Maghnite-H+

2018 ◽  
Vol 7 (4) ◽  
pp. 296-305 ◽  
Author(s):  
Djamal Eddine Kherroub ◽  
Mohammed Belbachir ◽  
Saad Lamouri
Keyword(s):  
Ring Opening ◽  
Polymerization Reaction ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Average Molecular Mass ◽  
Green Catalyst ◽  
New Approach ◽  
X Ray ◽  
Cationic Ring Opening Polymerization ◽  
C Nmr

Abstract This work is devoted to the study of the cationic ring opening polymerization of tetraphenyltetramethylcyclotetrasiloxane (D4Ph,Me), using a solid green catalyst prepared by the activation of a natural clay by sulfuric acid (Maghnite-H+). This treatment leads to the spacing of the montmorillonite sheets due to the substitution of the existing interlayer cations by the protons of the acid. This consequence is clearly shown on the X-ray diffraction (XRD) spectrum. The polymerization reaction proceeded in bulk and under mild conditions. Various tests were carried out by changing the temperature, the time and the catalyst mass content in order to increase, at the same time, the yield of the reaction and the average molecular mass of the polyphenylmethylsiloxane (PPMS) obtained. The structure of the PPMS obtained was identified by infrared (IR), 1H nuclear magnetic resonance (NMR) and 13C NMR analyses over different periods of time. The thermal behavior was investigated by differential scanning calorimetry (DSC) analysis. At the end, in order to show the role played by the Maghnite-H+ during the various reaction stages, a reaction mechanism was proposed.

Amino-functional polyethers: versatile, stimuli-responsive polymers

2020 ◽  
Vol 11 (24) ◽  
pp. 3940-3950 ◽  
Author(s):  
Patrick Verkoyen ◽  
Holger Frey
Keyword(s):  
Ring Opening ◽  
Review Article ◽  
Stimuli Responsive ◽  
New Class ◽  
Stimuli Responsive Polymers ◽  
Responsive Polymers

Amino-functional polyethers have emerged as a new class of “smart”, i.e. pH- and thermoresponsive materials. This review article summarizes the synthesis and applications of these materials, obtained from ring-opening of suitable epoxide monomers.

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