Lower critical solution temperature of poly

Maderek, E. Schulz, V. Wolf, B. A., "Lower Critical Solution Temperatures of Poly(decyl methacrylate) in Hydrocarbons," Eur. Polym. J., 19, 963 (1983). 

Kataoka K, Miyazaki H, Okano T, and Sakurai Y. Sensitive glucose-induced change of the lower critical solution temperature of poly[N, N-dimethylacrylamide-co-3-acrylamido[phenylhoronic acid] in physiological saline. Macromolecules 1994 27 1061-1062. 

Yoo, M.K., Sung, Y.K., Lee, Y.M. et al. 2000. Effect of polyelectrolyte on the lower critical solution temperature of poly(N-isopropyl acrylamide) in the poly(NlPAAm-co-acrylic acid) hydrogel. Polymer. 41 5713-5719. 

LES Lessard, D.G., Ousalem, M., and Zhu, X.X., Effect of the molecular weight on the lower critical solution temperature of poly(A,A/-diethylacrylamide) in aqueous solutions. Can. J. Chem., 79, 1870,2001. 

HU2 Huber, S., Hutter, N., and Jordan, R., Effect of end group polarity upon the lower critical solution temperature of poly(2-isopropyl-2-oxazoline). Colloid Polym. Sci., 286, 1653,2008.1... 

Lee, S. B. Song, S. C. Jin, J. I. Sohn, Y. S. A new class of biodegradable thermosensitive polymers. 2. Hydrolytic properties and salt effect on the lower critical solution temperature of poly(organophosphazenes) with methoxypoly(ethylene glycol) and amino acid esters as side groups. Macromolecules 1999, 32, 7820-7827. 

Madbouly Wolf, 2002, Equilibrium phase behavior of polyethylene oxide and of its mixtures with tetrahydronaphthalene or/and p ly (ethylene oxide-block-dimethylsiloxane), /, Chem. Phys., Vol. 117, No. 15, PP. 7357-7363 Maderek et al. 1983, High-temperature demixing of poly(decyl methacrylate) solutions in isooctane and its pressure-dependence, Makromol. Chem., Vol. 184, No. 6, PP. 1303-1309 Lower critical solution temperatures of poly(decyl methacrylate) in hydrocarbons, Eur. Polym.., Vol. 19, No. 10, PP. 963-965 Patterson Robard, 1978, Thermodynamics of polymer compatibility. Macromolecules, Vol. 11, No. 4, 690-695... 

ZE1 Zeman, L., Biros, J., Delmas, G., and Patterson, D., Pressure effects in polymer solution phase equilibria. I. The lower critical solution temperature of poly isobutylene and polydimethylsiloxane in lower alkanes, J. Phys. Chem., 76, 1206, 1972. 

Cowie, J. M. G. and McEwen, 1. J. (1976) Influence of microstracture on the upper and lower critical solution temperatures of poly(methyhnethacrylate) solutions, J Chem Soc Faraday Trans 1 Phys Chem Condensed Phases, 72,526-533, doi 10.1039/F19767200526. 

Suwa K, Morishita K, Kishida A et al. Synthesis and functionalities of poly(N-vinylalkylamide). V. Control of a lower critical solution temperature of poly(N-vinylalkylamide). J Polymer Sci 1997 35 3087-3094. 

Lee, S.B., Song, S.C., Jin, J.I., Sohn, Y.S. Surfactant effect on the lower critical solution temperature of poly(oiganophosphazBnes) with methoxy-poly(ethylene glycol) rmd tunino acid esters as side groups. CoUoid Pdym. Sd. 278(11), 1097-1102 (2000). doi 10.1007/s003960000368... 

SCF technology has spread quickly from molecules such as naphthalene to more complex substances such as polymers, biomolecules, and surfactants. Supercritical fluids can be used to reduce the lower critical solution temperature of polymer solutions in order to remove polymers from liquid solvents(6.26 The technology has been extended to induce crystallization of other substances besides polymers from liquids, and has been named gas recrystallization(4). In other important applications, SCF carbon dioxide has been used to accomplish challenging fractionations of poly(ethylene glycols) selectively based on molecular weight as discussed in this symposium, and of other polymers(. ... 

Interesting properties can be engineered into these materials by copolymerization. Copolymerization of 2-ethylacrylic acid or MAA with iV-[4-(phe-nylazo)phenyl]methacrylamide, a photosensitive monomer, results in polymers in which the interaction with lipid biolayers can be photoregulated [10, 11]. Thermally reversible polymers can be produced from poly(iV-isopropylacryla-mide), which is a water-soluble polymer at room temperature. The LCST (lower critical solution temperature) of the homopolymer is 32 °C at this temperature a reversible phase separation occurs. This LCST can be adjusted by copolymerization with more or less hydrophilic monomers. 

LIP Li, P.-F., Wang, W., Xie, R., Yang, M., Ju, X.-J., and Chu, L.-Y., Lower critical solution temperatures of thermo-responsive poly(A -isopropylaciylamide) copolymers with racemate or single enantiomer groups, Polym. Int, 58, 202, 2009. 

XUE Xue, W., Huglin, M.B., and Jones, T.G.J., Parameters affecting the lower critical solution temperature of linear and crosslinked poly(lV-ethylacrylamide) in aqueous media, A/ocrawo/. Chem. Phys., 204, 1956, 2003. 

Although most polymers tend to accumulate at the fluid interface, reports involving the transfer of polymeric micelles (micellar shuttle) between two immiscible phases have been pubHshed. Poly(N-isopropylacrylamide) (PNIPAM), a thermally responsive polymer, is insoluble and can undergo a conformation change above its lower critical solution temperature of 32 ° C. The thermo reversible miceUization—demicellization process and micellar shuttle of PNIPAM-PEO diblock copolymer at a water-IL interface were investigated by dissipative particle dynamics (DPD) simulations (Soto-Figueroa et al, 2012). Simulation results confirm that the phase transfer behavior of polymeric micelles is controlled by the temperature effect that changes the diblock copolymer from hydrophilic to hydrophobic (as shown in Fig. 33). 

Plumper, F. A., Schmalz, A., Ballauf, M. and Muller, A. H. E. (2007) Tuning the thermoresponsiveness of weak polyelectrolytes by pH and hght Lower and upper critical-solution temperature of poly(N,N-dimethylaminoethyl methacrylate),/ Am Chem Soc, 127,14538-14539, doi 10.1021/ja074720i. 

Photochemical modification of the lower critical solution temperature of cinnamoylated poly(N-2-hydroxypropylmethacrylamide) in water. Macrotnol. Rapid Commun.,... 

Park, J.-S. and Kataoka, K. (2006) Precise control of lower critical solution temperature of thermosensitive poly(2-isopropyl-2-oxazoUne) via gradient copolymerization with 2-ethyl-2-oxazoline as a hydrophilic comonomer. 

With less than 3.3 wt% CO2 sorption, the miscible blend of poly(deuterated styrene) and PVME phase separated at 115 °C lower than the control blend [73]. The exposure of the miscible PMMA/PVF2 blend to increasing CO2 pressure showed an increase in xu to zero and the onset of phase separation (at 35 °C) [74]. At high CO2 pressure, PVF2 crystallization occurred within the PMMA-rich matrix. The upper critical solution temperature of poly(dimethyl siloxane)/poly(ethyl methyl siloxane) showed an increase with increasing CO2 pressure [75]. It was noted that high pressure He (with very low solubility) yielded a decrease in the ucst. The sorption of modest levels of CO2 (up to 160 bar) decreased the lower critical solution temperature of deuterated polybutadiene/polyisoprene blends [76]. Each of these examples shows a decrease in miscibility with increasing CO2 pressure. 

Duan et alP also reported the synthesis of poly(A -isopropylacrylamide)-silica composite microspheres by using inverse Pickering suspension polymerization with various sizes of silica particles as stabilizers. Figure 1.14 shows examples of such microgels stabilized by silica particles with mean diameters of 53, 301, 500 and 962 nm. To generate these nanocomposite structures, droplets of an aqueous solution of 7V-isopropylacrylamide were first dispersed in toluene and then stabilized by silica particles. The monomer was subsequently polymerized to obtain polymer silica composite microspheres. It was also observed that the thermo-responsive behavior of the polymer was not affected in the presence of silica, as a lower critical solution temperature of 32 °C for the poly(A -isopropylacrylamide) was also observed in the polymer-silica microspheres. 

The phase transition temperatures (lower critical solution temperature, LCST) of the pol5miers were obtained from the change in the transmittance of their aqueous solutions (Figure 1). The aqueous solution of the obtained pol5uner was prepared and its transmittance at 500 nm was monitored with increase in the ambient temperature. Both of poly-NIPA and poly-NEA showed a sudden decrease in the transmittance at 37.5 and 69.2 °C, respectively. The result shown in Figure 1 clearly suggests the thermosensitivity of the pol5mers, and the obtained LCST values are close to those reported for poly-NIPA (34.8 °C) [8] and poly-NEA (72 °C) [9]. 

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