|
| ||
|
|
||
Brush Polymers (brush + polymer)
Selected AbstractsNovel Brush Polymers with Phosphorylcholine Bristle Ends: Synthesis, Structure, Properties, and BiocompatibilityADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Gahee Kim Abstract New brush polymers with various numbers of bristle ends incorporating phosphorylcholine (PC) moieties are synthesized. The polymers are thermally stable up to 175,°C and form good-quality films with conventional spin-, roll-, and dip-coating, and subsequent drying processes. Interestingly, all these brush polymers, as a PC-containing polymer, demonstrate a stable molecular multi-bilayer structure in thin films that arise due to the efficient self-assembly of the bristles for temperatures <55,°C and PC-rich surfaces, and therefore successfully mimic natural cell-membrane surfaces. These brush-polymer films exhibit excellent water wettability and water sorption whilst retaining the remarkable molecular multi-bilayer structure, and thus have hydrophilic surfaces. These novel multi-bilayer structured films repel fibrinogen molecules and platelets from their surfaces but also have bactericidal effects on bacteria. Moreover, the brush-polymer films are found to provide comfortable surface environments for the successful anchoring and growth of HEp-2 cells, and to exhibit excellent biocompatibility in mice. These newly developed brush polymers are suitable for use in biomedical applications including medical devices and biosensors that require biocompatibility and the reduced possibility of post-operative infection. [source] Surfactant-Induced Helix Formation of Cylindrical Brush Polymers with Poly(L -lysine) Side ChainsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 10 2008Nikhil Gunari Abstract The complex formation of oppositely charged surfactants with some polypeptides is known to induce , -sheet or helix formation. Here, we report on the complex formation of cylindrical brush polymers with poly(L -lysine) side chains and sodium dodecylsulfate (SDS). With increasing amount of added surfactant the cylindrical polymers first adopt a helical conformation with a pitch of approximately 14,24 nm followed by a spherically collapsed structure before eventually precipitation occurs. CD measurements suggest that the helix formation of the cylindrical brush polymers is driven by the hydrophobicity of the , -sheets formed by the PLL side chain,SDS complexes. [source] Novel Brush Polymers with Phosphorylcholine Bristle Ends: Synthesis, Structure, Properties, and BiocompatibilityADVANCED FUNCTIONAL MATERIALS, Issue 10 2009Gahee Kim Abstract New brush polymers with various numbers of bristle ends incorporating phosphorylcholine (PC) moieties are synthesized. The polymers are thermally stable up to 175,°C and form good-quality films with conventional spin-, roll-, and dip-coating, and subsequent drying processes. Interestingly, all these brush polymers, as a PC-containing polymer, demonstrate a stable molecular multi-bilayer structure in thin films that arise due to the efficient self-assembly of the bristles for temperatures <55,°C and PC-rich surfaces, and therefore successfully mimic natural cell-membrane surfaces. These brush-polymer films exhibit excellent water wettability and water sorption whilst retaining the remarkable molecular multi-bilayer structure, and thus have hydrophilic surfaces. These novel multi-bilayer structured films repel fibrinogen molecules and platelets from their surfaces but also have bactericidal effects on bacteria. Moreover, the brush-polymer films are found to provide comfortable surface environments for the successful anchoring and growth of HEp-2 cells, and to exhibit excellent biocompatibility in mice. These newly developed brush polymers are suitable for use in biomedical applications including medical devices and biosensors that require biocompatibility and the reduced possibility of post-operative infection. [source] Surfactant-Induced Helix Formation of Cylindrical Brush Polymers with Poly(L -lysine) Side ChainsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 10 2008Nikhil Gunari Abstract The complex formation of oppositely charged surfactants with some polypeptides is known to induce , -sheet or helix formation. Here, we report on the complex formation of cylindrical brush polymers with poly(L -lysine) side chains and sodium dodecylsulfate (SDS). With increasing amount of added surfactant the cylindrical polymers first adopt a helical conformation with a pitch of approximately 14,24 nm followed by a spherically collapsed structure before eventually precipitation occurs. CD measurements suggest that the helix formation of the cylindrical brush polymers is driven by the hydrophobicity of the , -sheets formed by the PLL side chain,SDS complexes. [source] One- and Two-Component Bottle-Brush Polymers: Simulations Compared to Theoretical PredictionsMACROMOLECULAR THEORY AND SIMULATIONS, Issue 7 2007Hsiao-Ping Hsu Abstract Scaling predictions for bottle-brush polymers with a rigid backbone and flexible side chains under good solvent conditions are discussed and their validity is assessed by a comparison with Monte Carlo simulations of a simple lattice model. It is shown that typically only a rather weak stretching of the side chains is realized, and then the scaling predictions are not applicable. Also two-component bottle brush polymers are considered, where two types (A,B) of side chains are grafted, assuming that monomers of different kind repel each other. In this case, variable solvent quality is allowed. Theories predict "Janus cylinder"-type phase separation along the backbone in this case. The Monte Carlo simulations, using the pruned-enriched Rosenbluth method (PERM) give evidence that the phase separation between an A-rich part of the cylindrical molecule and a B-rich part can only occur locally. The correlation length of this microphase separation can be controlled by the solvent quality. This lack of a phase transition is interpreted by an analogy with models for ferromagnets in one space dimension. [source] | ||||||||||