Untitled

Chiu, S. C.; Kwei, T. K.; Pearce, Eli M.

doi:10.1023/a:1010171509415

Cited by 2 publications

(3 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If so, one would expect each (homogeneous) polymer blend to have a single glass transition temperature. 64,65 Figure 7 shows an overlay of c p upon cooling for blends of different composition. Those blends containing less than 40 wt % or more than 87 wt % of PNIPAM can indeed be described by a single, composition-dependent T g , seen as a stepwise decrease in c p upon cooling.…”

Section: Resultsmentioning

confidence: 99%

“…All PNIPAM 187000 /PEO 300 blends are transparent at room temperature, and they remain transparent upon heating up to 150 °C as observed by optical microscopy, thus suggesting miscibility within the entire composition range up to 150 °C. If so, one would expect each (homogeneous) polymer blend to have a single glass transition temperature. , Figure shows an overlay of c p upon cooling for blends of different composition. Those blends containing less than 40 wt % or more than 87 wt % of PNIPAM can indeed be described by a single, composition-dependent T g , seen as a stepwise decrease in c p upon cooling.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Influence of Macromolecular Architecture on the Thermal Response Rate of Amphiphilic Copolymers, Based on Poly(N-isopropylacrylamide) and Poly(oxyethylene), in Water

et al. 2007

View full text Add to dashboard Cite

The effect of poly(oxyethylene), PEO, on the thermal response rate of aqueous solutions of poly(N-isopropylacrylamide), PNIPAM, block and graft copolymers has been discussed. The PNIPAM-b-PEO/water system reveals thermoresponsive properties similar to the PNIPAM/water system. In PNIPAM-g-PEO/water solutions, however, PEO provides hydrophilic channels, facilitating the diffusion of water molecules through the collapsed polymer aggregate at temperatures above the demixing temperature of the aqueous copolymer solution. As a result, the thermal response of the aqueous PNIPAM-g-PEO system is significantly faster than in the case of either pure PNIPAM or PNIPAM-b-PEO, indicating the influence of the macromolecular architecture. An attempt has also been made to correlate the thermal response kinetics of the aqueous solutions of different copolymers with the miscibility of the polymer constituents, i.e., PEO and the thermoresponsive PNIPAM backbone, which can vitrify during phase separation.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Influence of Macromolecular Architecture on the Thermal Response Rate of Amphiphilic Copolymers, Based on Poly(N-isopropylacrylamide) and Poly(oxyethylene), in Water

et al. 2007

View full text Add to dashboard Cite

show abstract

“…One such favorable interaction is hydrogen bonding that has been reported for many polymer blends 3–7. Although a considerable amount of research work has been performed on the contribution of hydrogen bonding to the phase behavior of polymer blends,8–13 there is lack of mechanistic understanding of effects of hydrogen bonding on the phase state of polymer blends.…”

Section: Introductionmentioning

confidence: 99%

Competitive hydrogen bonding mechanisms underlying phase behavior of triple poly(N‐vinyl pyrrolidone)–poly(ethylene glycol)–poly(methacrylic acid‐co‐ethylacrylate) blends

Kireeva

Shandryuk

Kostina

et al. 2007

J of Applied Polymer Sci

View full text Add to dashboard Cite

Differential scanning calorimetry (DSC) of triple blends of high molecular weight poly(N‐vinyl pyrrolidone) (PVP) with oligomeric poly(ethylene glycol) (PEG) of molecular weight 400 g/mol and copolymer of methacrylic acid with ethylacrylate (PMAA‐co‐EA) demonstrates partial miscibility of polymer components, which is due to formation of interpolymer hydrogen bonds (reversible crosslinking). Because both PVP and PMAA‐co‐EA are amorphous polymers and PEG exhibits crystalline phase, the DSC examination is informative on the phase state of PEG in the triple blends and reveals a strong competition between PEG and PMAA‐co‐EA for interaction with PVP. The hydrogen bonding in the triple PVP–PEG–PMAA‐co‐EA blends has been established with FTIR Spectroscopy. To evaluate the relative strengths of hydrogen bonded complexes in PVP–PEG–PMAA‐co‐EA blends, quantum‐chemical calculations were performed. According to this analysis, the energy of H‐bonding has been found to diminish in the order: PVP–PMAA‐co‐EA–PEG(OH) > PVP–(OH)PEG(OH)–PVP > PVP–H2O > PVP–PEG(OH) > PMAA‐co‐EA–PEG(O) > PVP–PMAA‐co‐EA > PMAA‐co‐EA–PEG(OH). Thus, most stable complexes are the triple PVP–PMAA‐co‐EA–PEG(OH) complex and the complex wherein comparatively short PEG chains form simultaneously two hydrogen bonds to PVP carbonyl groups through both terminal OH‐groups, acting as H‐bonding crosslinks between longer PVP backbones. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

show abstract

Untitled

Cited by 2 publications

References 10 publications

Influence of Macromolecular Architecture on the Thermal Response Rate of Amphiphilic Copolymers, Based on Poly(N-isopropylacrylamide) and Poly(oxyethylene), in Water

Influence of Macromolecular Architecture on the Thermal Response Rate of Amphiphilic Copolymers, Based on Poly(N-isopropylacrylamide) and Poly(oxyethylene), in Water

Competitive hydrogen bonding mechanisms underlying phase behavior of triple poly(N‐vinyl pyrrolidone)–poly(ethylene glycol)–poly(methacrylic acid‐co‐ethylacrylate) blends

Contact Info

Product

Resources

About