scholarly journals Cyclodextrins in polymer synthesis: Dimethyl-β-cyclodextrin as thermosensitive retardant for the radical polymerization of N-methacryloyl-L-tyrosine derivatives in water

e-Polymers ◽  
2002 ◽  
Vol 2 (1) ◽  
Author(s):  
Monir Tabatabai ◽  
Helmut Ritter ◽  
Monika Schmelzer
Keyword(s):  
Molecular Weight ◽  
Methyl Ester ◽  
Radical Polymerization ◽  
Ethyl Ester ◽  
Room Temperature ◽  
Water Soluble ◽  
Synthesis And Characterization ◽  
Organic Solution ◽  
Tyrosine Derivatives

AbstractThe synthesis and characterization of N-methacryloyl-L-tyrosine methyl ester (3a) and ethyl ester (3b), and their acetyl derivatives O-acetyl-N-methacryloyl- L-tyrosine methyl ester (4a) and ethyl ester (4b) are described. Monomers 3 and 4 were complexed with RAMEB (randomly methylated ß-cyclodextrin) yielding water soluble host-guest complexes 5a-d. The radical polymerization of monomers 3 and 4 was investigated in the presence as well as in the absence of RAMEB in aqueous medium at room temperature and also at 60°C. It is shown that the polymerization tendency of complexes 5a-d at room temperature is lower, leading to polymers of higher molecular weight, compared to the free monomers 3 and 4. Furthermore, the polymerization of monomers 3 and 4 was carried out in homogenous organic solution using 2,2’-azoisobutyronitrile as initiator, and the results are discussed.

Quadrol-Pd(II) complexes: phosphine-free precatalysts for the room-temperature Suzuki-Miyaura synthesis of nucleoside analogues in aqueous media

2022 ◽  
Author(s):  
Jose Luis Serrano ◽  
Sujeet Gaware ◽  
Jose Antonio Pérez de Haro ◽  
Jose Pérez ◽  
Pedro Lozano ◽  
...  
Keyword(s):  
Room Temperature ◽  
Aqueous Media ◽  
Water Soluble ◽  
Nucleoside Analogues ◽  
Synthesis And Characterization ◽  
First Time

Commercially available Quadrol, N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine (THPEN), has been used for the first time as N^N- donor neutral hydrophilic ligand in the synthesis and characterization of new water soluble palladium (II) complexes...

scholarly journals Synthesis and Characterization of Colored Polyureas

2004 ◽  
Vol 1 (1) ◽  
pp. 51-56 ◽  
Author(s):  
M. G. Patel ◽  
K. R. Desai ◽  
H. S. Patel
Keyword(s):  
Electrical Conductivity ◽  
Molecular Weight ◽  
Room Temperature ◽  
Average Molecular Weight ◽  
Conductometric Titration ◽  
Spectral Studies ◽  
Synthesis And Characterization ◽  
Disperse Dyes ◽  
Number Average Molecular Weight

Various disperse dyes based onm-phenylenediamine have been prepared. These dyes then polycondensation with 4,4'-Diphenyl methane diisocyanate. The resultant colored polyureas were characterized by N content, IR spectral studies, Number Average Molecular Weight (Mn) estimation by nonaqueous conductometric titration and thermogravimetry. All the polyureas were subjected to measure electrical conductivity at room temperature.

scholarly journals Synthesis and Characterization of New Mesomorphic Azo Compounds and Study their Photoluminesecence Properties

2016 ◽  
Vol 13 (2) ◽  
pp. 333-344
Author(s):  
Baghdad Science Journal
Keyword(s):  
Liquid Crystal ◽  
Optical Microscopy ◽  
Elemental Analysis ◽  
Room Temperature ◽  
Azo Compounds ◽  
Synthesis And Characterization ◽  
Photoluminescence Properties ◽  
Organic Solution ◽  
Polymeric Liquid

The preparation of a new Azo compounds of highly conjugated dimeric and polymeric liquid crystal to achieve the crystalline characteristics Which have structures assigned based on elemental analysis, IR 1HNMR and CHNS-O while mesogenic properties have been set for DSC and hot-stage polarizing optical microscopy. The compounds show enantiotropicnematic phase being displayed. The compounds show photoluminescence properties in the organic solution at room temperature, with the fluorescence band centered around 400 nm.

scholarly journals Synthesis and characterization of a new ZIF-67@MgAl2O4 nanocomposite and its adsorption behaviour

RSC Advances ◽  
2021 ◽  
Vol 11 (22) ◽  
pp. 13245-13255
Author(s):  
Mehdi Davoodi ◽  
Fatemeh Davar ◽  
Mohammad R. Rezayat ◽  
Mohammad T. Jafari ◽  
Mehdi Bazarganipour ◽  
...  
Keyword(s):  
Room Temperature ◽  
Magnesium Aluminate ◽  
Synthesis And Characterization ◽  
Magnesium Aluminate Spinel ◽  
Adsorption Behaviour ◽  
Zeolitic Imidazolate Framework ◽  
Simple Method

New nanocomposite of zeolitic imidazolate framework-67@magnesium aluminate spinel (ZIF-67@MgAl2O4) has been fabricated by a simple method at room temperature with different weight ratios.

scholarly journals Semi-Crystalline Hydrophobic Polyamidoamines: A New Family of Technological Materials?

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1018
Author(s):  
Massimo Marcioni ◽  
Jenny Alongi ◽  
Elisabetta Ranucci ◽  
Mario Malinconico ◽  
Paola Laurienzo ◽  
...  
Keyword(s):  
Maximum Stress ◽  
Water Resistance ◽  
Prolonged Exposure ◽  
Water Soluble ◽  
Synthesis And Characterization ◽  
Molecular Weights ◽  
New Family ◽  
Methylene Groups ◽  
Methane Flame

The hitherto known polyamidoamines (PAAs) are not suitable as structural materials because they are usually water-soluble or swellable in water. This paper deals with the synthesis and characterization of semi-crystalline hydrophobic PAAs (H-PAAs) by combining different bis-sec-amines with bis-acrylamides obtained from C6–C12 bis-prim-amines. H-PAAs were initially obtained in a solution of benzyl alcohol, a solvent suitable for both monomers and polymers. Their number average molecular weights, M¯n, which were determined with 1H-NMR by evaluating the percentage of their terminal units, varied from 6000 to >10,000. The solubility, thermal properties, ignitability and water resistance of H-PAAs were determined. They were soluble in organic solvents, semi-crystalline and thermally stable. The most promising ones were also prepared using a bulk process, which has never been previously reported for PAA synthesis. In the form of films, these H-PAAs were apparently unaffected by water. The films underwent tensile and wettability tests. They showed similar Young moduli (260–263 MPa), whereas the maximum stress and the stress at break depended on the number of methylene groups of the starting bis-acrylamides. Their wettability was somewhat higher than that of common Nylons. Interestingly, none of the H-PAAs considered, either as films or powders, ignited after prolonged exposure to a methane flame.

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