Preparation and characterization of polyethersulfone membranes with p-toluenesulfonic acid and polyvinylpyrrolidone additives

Desalination ◽  
2008 ◽  
Vol 233 (1-3) ◽  
pp. 218-226 ◽  
Author(s):  
Nowon Kim ◽  
Chung-Sook Kim ◽  
Yong-Taek Lee
Keyword(s):  
Holzforschung ◽  
2018 ◽  
Vol 72 (11) ◽  
pp. 933-942 ◽  
Author(s):  
Qianli Ma ◽  
Liheng Chen ◽  
Ruibin Wang ◽  
Rendang Yang ◽  
J.Y. Zhu

AbstractLignin nanoparticles (LNPs) from renewable lignocelluloses can be a valuable building block for a variety of applications and could contribute to the economic development in rural agricultural communities. Current technologies for producing LNPs are not cost effective and use toxic solvents. In this study, LNPs were produced by fractionating poplar wood at ≤80°C with a recyclable hydrotropep-toluenesulfonic acid (p-TsOH) in an aqueous system. The dissolved lignin was separated as LNPs simply by diluting the spent liquor (SL) to the minimal hydrotrope concentration (HCmin) of 11.5%. Thep-TsOH, a solid acid, can be easily recycled by re-concentrating the diluted SL after lignin separation. The LNP size, morphology, and surface charge were controlled by the dilution ratio, speed, pH, and ionic strength of the LNP sol. The LNPs were analyzed by dynamic light scattering (DLS) and found to be fairly stable in terms of mean particle size and surface charge over a period of 2 weeks. Fractionation conditions also affected LNP properties.


2002 ◽  
Vol 06 (09) ◽  
pp. 571-577 ◽  
Author(s):  
Tamer E. Youssef ◽  
Michael Hanack

A general synthesis of unsymmetrically substituted dienophilic nickel phthalocyanines is described. The desired nickel phthalocyanine complexes [3,4,10,11,17,18-hexakis(2-ethyl-hexyloxy)tribenzo(b,g,i]-24,27-di-hydro-24,27-epoxynaphthalo[q]porphyrazinato]nickel(II) (4) and dodeca alkoxy-substituted PcNi (5) were synthesized using a statistical approach by the condensation of 1,2-dicyano-4,5-bis(2-ethylhexyloxy)benzene (1) or 1,2-dicyano-3,4,5,6-tetrakis(2-ethylhexyloxy)benzene (2) and 6,7-dicyano-1,4-dihydro-1,4-epoxy-1,4-dimethylnaphthalene (3) in the presence of nickel(II) acetate. Reaction of 4 or 5 with tetraphenyl-cyclopentadieneone (9) lead to the phthalocyanine-tetracyclone adducts 10 and 11, respectively, which are precursors for intermediate adducts 12 and 13 containing isobenzofuran moiety as diene subunits. The dimer 14 was synthesized from 4 and the isobenzofuran intermediate 12. Dehydrogenation of the Diels-Alder product 14 to the fully conjugated derivative 15 was carried out successfully with p-toluenesulfonic acid.


e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Ana-Maria Pană ◽  
Lucian-Mircea Rusnac ◽  
Geza Bandur ◽  
Mihaela Silion ◽  
Călin Deleanu ◽  
...  

AbstractThis paper presents the synthesis and characterization of two oligomers based on monosaccharides (D-glucose and D-mannose). The oligomers were obtained by the polycondensation of two diacids derived from monosaccharides (3- O-benzyl-5,6-(bis(maleyloxy))-1,2-O-isopropylideneglucofuranose and 1-O-benzyl- 5,6-(bis(maleyloxy))-2,3-O-isopropylidenemannofuranose, respectively), with propane-1,3-diol in the presence of p-toluenesulfonic acid. The oligomers were characterized using FTIR and NMR spectroscopy, HPLC-MS and DSC. The copolymerization of the oligomers with 2-hydroxy-propyl acrylate was studied by DSC to evaluate the possibility of obtaining cross-linked copolymers.


2018 ◽  
Vol 1156 ◽  
pp. 684-689 ◽  
Author(s):  
Rengasamy Chithiravel ◽  
Kandasamy Rajaguru ◽  
Shanmugam Muthusubramanian ◽  
Nattamai Bhuvanesh

2000 ◽  
Vol 19 (10) ◽  
pp. 1940-1949 ◽  
Author(s):  
Christophe Eychenne-Baron ◽  
François Ribot ◽  
Nathalie Steunou ◽  
Clément Sanchez ◽  
Franck Fayon ◽  
...  

2007 ◽  
Vol 107 (6) ◽  
pp. 3925-3932 ◽  
Author(s):  
Duk Ki Kim ◽  
Kyung Wha Oh ◽  
Hee Jun Ahn ◽  
Seong Hun Kim

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