Results 131 to 140 of about 57,276 (400)

Advances in Metal‐Free Transamidation: A Sustainable Approach to Amide Bond Formation

Chemistry – An Asian Journal, EarlyView.
This review highlights the recent developments of transamidation reactions under metal‐free reaction conditions. Various amines including weak nucleophilic amines such as aromatic amines have been used to achieve the transamidation reactions under mild and relatively green reaction conditions. Abstract The amide functionalities are a crucial functional
Niharan Sivaraj, Toshifumi Dohi, Fateh V. Singh   +2 more
wiley   +1 more source

Thermo‐mechanical properties of flexible and rigid polyurethane (PU)/Cu composites

Polymer Composites, Volume 44, Issue 1, Page 401-412, January 2023., 2023
Synthesis of flexible and rigid polyurethane (PU)/copper composites and its thermal, mechanical properties analysis, and comparison. Abstract In this article, flexible and rigid polyurethane (PU)/copper (Cu) composites are prepared via a simple and cost‐effective solution casting process.
Patcharapon Somdee, Manauwar Ali Ansari, Kálmán Marossy   +2 more
wiley   +1 more source

Homochiral Acyl Isocyanates as Diagnostic NMR Probes for the Enantiomeric Purity of Chiral Alcohols

Sultan Qaboos University Journal for Science, 2000
The first reported acyl and sulfonylisocyanates were developed and tested in reactions with chiral alcohols to afford diastereomeric carbamates. NMR analysis of these investigates the chemical shift discrimination that would allow these activated ...
Gregory H. P. Roos, Anthony R. Donovanb
doaj   +1 more source

The fire toxicity of polyurethane foams [Review] [PDF]

, 2016
Polyurethane is widely used, with its two major applications, soft furnishings and insulation, having low thermal inertia, and hence enhanced flammability.
A Tewarson, AA Stec, AA Stec, AA Stec, AV Wisnewski, B Andersson, B Bott, B Schartel, BC Levin, BC Levin, BC Levin, BH Chun, BP Kavanagh, D Allan, DA Purser, DA Purser, DA Purser, DG Farrar, DG Farrar, DT Gottuk, E Braun, Fire Test Procedure Code, G Hartzell, G Kimmerle, G Rein, H Henneken, H Singh, HL Kaplan, HL Kaplan, J Chambers, J Hietaniemi, J Michal, J Voorhees, JH Saunders, JL Neviaser, KT Paul, L Schnipper, L Shufen, M Blais, M Christy, M Paabo, M Ravey, MA Garrido, P Blomqvist, P Blomqvist, PL Piirilä, R Herrington, RA Anderson, SV Levchik, T Hertzberg, T Rogaume, TR Hull, V Babrauskas, V Babrauskas, V Babrauskas, V Babrauskas, V Barbrauskas, V Barbrauskas, WD Vilar, WD Woolley, WD Woolley, WM Pitts, X Guo, Y Alarie   +63 more
core   +1 more source

Technical lignin‐derived liquid polyols for flexible polyurethane foam in automotive seating

Biofuels, Bioproducts and Biorefining, EarlyView.
Abstract In this study, three different technical lignins from different biomass sources (softwood, hardwood, and wheat straw) and isolation processes (kraft, hydrolysis, and organosolv) were used to synthesize liquid lignin polyols by oxyalkylating lignin with propylene carbonate, a safe and environmentally friendly solvent.
Kevin Dunne, Enoch Kofi Acquah, Tara Allohverdi, Rachel Schenck, Mojgan Nejad   +4 more
wiley   +1 more source

Nitrogen Chemistry Significant to Primordial Systems Semiannual Report, 1 Jul. - 31 Dec. 1966 [PDF]

Deoxygenation of benzoyl cyanide, studies of vinyl nitrenes and diene isocyanates, and other aspects of nitrogen chemistry significant to primordial biological ...
Boyer, J. H.
core   +1 more source

New urea-absorbing polymers for artificial kidney machines [PDF]

, 1975
Etherified polymer is made from modified cellulose derivative which is reacted with periodate. It will absorb 2 grams of urea per 100 grams of polymer.
Hsu, G. C., Marsh, H. E., Jr., Mueller, W. A.   +2 more
core   +1 more source

Purine Chemistry in the Early RNA World at the Origins of Life: From RNA and Nucleobases Lesions to Current Key Metabolic Routes

ChemBioChem, EarlyView.
In the nascent processes of the beginnings and evolution of life, nucleobases and especially purines, ribonucleos(t)ides and primitive RNAs have been continuously modified. A RNA‐peptide world and key metabolic pathways probably have emerged from the corresponding chemical modifications resulting from adenine deamination, purine alkylation and ...
Jean‐Luc Décout, Marie‐Christine Maurel   +1 more
wiley   +1 more source

Occupational allergic and irritant contact dermatitis in workers exposed to polyurethane foam

International Journal of Occupational Medicine and Environmental Health, 2014
Objectives: To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4'-diphenylmethane diisocyanate (MDI).
Marta Kieć-Świerczyńska, Dominika Świerczyńska-Machura, Dorota Chomiczewska-Skóra, Ewa Nowakowska-Świrta, Beata Kręcisz   +4 more
doaj  

Evaluation of respiratory exposure to 4,4-methylene diphenyl diisocyanate (MDI) vapors in foam injection workers in a household appliance manufacturing company: An Occupational Carcinogen

Asian Pacific Journal of Environment and Cancer, 2019
Background: Appliance manufacturing boom is very high hand customers always have a great deal of attention to products that have low energy consumption, therefore the use of isocyanates MDI as a thermal insulation in the body of the refrigerator and is ...
Ahmad Nikpey, Hamzeh Saeidabadi, Salman Sheikhi, Saeed Yari, Tayyebeh Jaddi Madarsara   +4 more
doaj   +1 more source