4694-80-8Relevant articles and documents
Synthesis of pH- and thermoresponsive poly(2-n-propyl-2-oxazoline) based copolymers
Boerman, Marcel A.,Van Der Laan, Harry L.,Bender, Johan C. M. E.,Hoogenboom, Richard,Jansen, John A.,Leeuwenburgh, Sander C.,Van Hest, Jan C. M.
, p. 1573 - 1582 (2016/05/09)
Polymers that possess lower critical solution temperature behavior such as poly(2-alkyl-2-oxazoline)s (PAOx) are interesting for their application as stimulus-responsive materials, for example in the biomedical field. In this work, we discuss the scalable and controlled synthesis of a library of pH- and temperature-sensitive 2-n-propyl-2-oxazoline P(nPropOx) based copolymers containing amine and carboxylic acid functionalized side chains by cationic ring opening polymerization and postpolymerization functionalization strategies. Using turbidimetry, we found that the cloud point temperature (CP) is strongly dependent on both the polymer concentration and the polymer charge (as a function of pH). Furthermore, we observed that the CP decreased with increasing salt concentration, whereas the CP increased linearly with increasing amount of carboxylic acid groups. Finally, turbidimetry studies in PBS-buffer indicate that CPs of these polymers are close to body temperature at biologically relevant polymer concentrations, which demonstrates the potential of P(nPropOx) as stimulus-responsive polymeric systems in, for example, drug delivery applications.
Method for inhibiting hydrate formation
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, (2008/06/13)
A method for inhibiting the formation of clathrate hydrates in a fluid having hydrate forming constituents is disclosed. More specifically, the method can be used in treating a petroleum fluid stream such as natural gas conveyed in a pipe to inhibit the formation of a hydrate restriction in the pipe. The hydrate inhibitors used for practicing the method are substantially water soluble polymers formed from a cyclic imino ether. Some examples of such inhibitors include various N-acyl polyalkyleneimines, such as N-acyl substituted polyethyleneimine, N-acyl substituted polypropyleneimine, N-acyl substituted polybutyleneimine, N-acyl substituted polypentyleneimine and copolymers thereof. Also, such N-acyl substituted polyalkyleneimines can be used in various ratios with other substantially water soluble polymers and copolymers. Preferably, a solvent such as water, brine, alcohol, or mixtures thereof is used to produce an inhibitor solution or mixture to facilitate treatment of the petroleum fluid stream.