Polymers in Aqueous Media

Chain-Growth Associative Thickeners. Preparation of hydrophobically modified, water-soluble polymer in aqueous media by a chain-growth mechanism presents a unique challenge in that the hydrophobically modified monomers are surface active and form micelles (50). Although the initiation and propagation occurs primarily in the aqueous phase, when the propagating radical enters the micelle the hydrophobically modified monomers then polymerize in blocks. In addition, the hydrophobically modified monomer possesses a different reactivity ratio (42) than the unmodified monomer, and the composition of the polymer chain therefore varies considerably with conversion (57). The most extensively studied monomer of this class has been acrylamide, but there have been others such as the modification of PVAlc. Pyridine (58) was one of the first chain-growth polymers to be hydrophobically modified. This modification is a post-polymerization alkylation reaction and produces a random distribution of hydrophobic units. 

J. E. Glass, ed.. Polymers in Aqueous Media, Performance through Association, Advances in Chemistry 223, American Chemical Society, Washington,... 

Borated starch compositions are useful for controlling the rate of cross-linking of hydratable polymers in aqueous media for use in fracturing fluids. The borated starch compositions are prepared by reacting, in an aqueous medium, starch and a borate source to form a borated starch complex. This complex provides a source of borate ions, which cause crosslinking of hydratable polymers in aqueous media [1552]. Delayed crosslinking takes place at low temperatures. 

RF Ofstead, Cl Posner. Semicrystalline poly(vinyl alcohol) hydrogels. In J Glass, ed. Polymers in Aqueous Media. Washington, DC American Chemical Society, 1989, pp 61-72. 

Phase transitions of aqueous polymer solutions have been the subject of several earlier reviews [97-104], In this review, we will focus primarily on the collapse of neutral water-soluble polymers in aqueous media and the var-... 

Peters A, Schosseler F, Candau SJ (1989) In Glass J (ed) Polymer in aqueous media performance through association. Advances in chemistry series 223. American Chemical Society, Washington, DC, p 45... 

Preparation of hydrophobically modified, water-soluble polymer in aqueous media by a chain growth mechanism presents a unique challenge in that the hydrophobically modified monomers are surface active and form micelles. 

Poly(N-isopropylacrylamide) (PNIPAM) is the most studied thermosensitive polymer in aqueous media. It is soluble in water at low temperatures but becomes insoluble when the temperature is increased above a certain temperature ( 32 °C) (lower critical solution temperature), which is related to the coil-to-globule transition [64, 65]. In the case of a polymer network, a volume change occurs reversibly within a narrow temperature range. The properties of such microgels can be varied to a great extent by the introduction... 

Kulicke, W.-M., and Nottelmann, H. (1989). Structure and swelling of some synthetic, semisynthetic, and biopolymer hydrogels. In Polymers in Aqueous Media, Glass, J. E. (Ed.), Advances in Chemistry 223, pp. 15-44. Am. Chem. Soc., Washington, DC. 

Glass JE (ed) (1989) Polymers in aqueous media. Adv chemistry series 223, Am Chem Soc, Washington DC... 

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