A study on solution properties of poly(N,N‐diethylacrylamide‐co‐acrylic acid)

Abstract

Poly(N,N-diethylacrylamide) (PDEA), poly (acrylic acid) (PAA), and a series of (N,N-diethylacrylamide-co-acrylic acid) (DEA-AA) random copolymers were synthesized by the method of radical polymerization. The measurement of turbidity showed that the phase behaviors of the brine solutions of the copolymers changed dramatically with the mole fraction of DEA (x) in these copolymers. Copolymers cop6 (x ¼ 0.06) and cop11 (x ¼ 0.11) in which acrylic acid content was higher presented the upper critical solution temperature (UCST) phase behaviors similar to PAA. Copolymer cop27 (x ¼ 0.27) presented the lower critical solution temperature (LCST) behavior similar to PDEA. While copolymer cop18 (x ¼ 0.18) in which acrylic acid content was moderate presented both UCST and LCST behaviors. The solution properties of the polymers were investigated by measurements of viscosity, fluorescence, and pH. It is reasonable to suggest that the sharp change of the phase behavior may be attributed to the interaction between acrylamide group and carboxylic group in the (DEA-AA) copolymers.

Transformer Hydrogels: A Review

“…Consequently, a focus is on creating nonionic UCST hydrogels and also dual LCST‐ and UCST‐responsive hydrogels . For example, by combining AAm or AAc with NIPAM, diethylacrylamide or vinylacetamide, hydrogels showing both LCST and UCST responsiveness can be formed. Other examples of hydrogels showing dual thermoresponsivity are copolymers of poly(ethylene glycol) and poly(acrylamide‐ co ‐acrylonitrile), and poly(imidazoled glycidyl methacrylate‐ co ‐diethyleneglycol methyl ether methacrylate) .…”

Fabrication and characterization of bifunctional spherical polyelectrolyte brushes

“…[41][42][43][44][45] Adding comonomer to alter the hydrophilic/ hydrophobic balance of polymers is one of the effective ways. [46] In this work, we incorporated AA monomer into thermo-sensitive polymer chains to adjust the hydrophilic/ hydrophobic balance of PNIPAM and PDEA chains.…”

Upper or lower critical solution temperature, or both? Studies on cationic copolymers of N-isopropylacrylamide

“…Some examples of other copolymers with such behaviour in aqueous systems exist, however. [48][49][50] Bis(trifluoromethane)sulfonimide (NTf 2 ) is known to turn many polycations insoluble in water. 51 This anion was recently used to modify the thermal response of a weak polycation, poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA).…”

“…Other investigators have shown that it is possible to influence the T c of analogous polymers by ionic strength. [48][49][50]54 By introducing a hydrophobic anion and simultaneously changing the ionic strength with a simple salt it should be possible to change the thermal response of the copolymers over a wide range of temperatures.…”