Double stimuli-responsive behavior of graft copolymer with polyimide backbone and poly(N,N-dimethylaminoethyl methacrylate) side chains

Synthesis, Structure, Hydrodynamics and Thermoresponsiveness of Graft Copolymer with Aromatic Polyester Backbone at Poly(2-isopropyl-2-oxazoline) Side Chains

“…However, this issue requires additional research. The maximum time to establish an “equilibrium” state for APE-g-PiPrOx solutions was 11,000 s, which is comparable with values for APE-g-PEtOx with a close MM [ 46 , 47 ] and for polymer brushes with polyimide backbone and poly ( N , N -dimethylaminoethyl methacrylate) side chains [ 29 ], but noticeably less than for star-shaped PAOx [ 86 ]. For model PiPrOx-m, the times were noticeably lower, ranging from 2000 to 4000 s. The acceleration of self-organization processes for linear polymers compared to polymers of complex architecture was typical.…”

“…The graft-copolymer composition affords the design of systems stimuli-responsive properties, including solubility, viscosity, and supramolecular association [ 16 , 27 , 28 , 29 , 30 , 31 ]. Given their brush-like architecture, graft copolymers display distinct stimuli-responsive behaviors.…”

Synthesis, Characterization, and Investigation of Thermosensitive Star-Shaped Poly(2-isopropyl-2-oxazolines) Based on Carbosilane Dendrimers

“…This makes it possible to conclude that these particles are individual macromolecules of star. Their structure is probably similar to that of unimolecular micelles of “core–shell” type, whose arms are strongly folded. The scattering objects with middle R h‐m and large R h‐s hydrodynamic radii are supramolecular structures, which are often called micelle‐like aggregates and loose aggregates, accordingly.…”

Amphiphilic Molecular Brushes with Regular Polydimethylsiloxane Backbone and Poly-2-isopropyl-2-oxazoline Side Chains. 2. Self-Organization in Aqueous Solutions on Heating

“…The t eq and t eq (max) values obtained for the investigated molecular brushes are greater than the typical “settling” times for linear thermosensitive polymers [ 26 , 80 , 81 ]. For other molecular brushes, the t eq (max) values of similar order of magnitude were obtained: for APE- g -PAlOx, the time t eq (max) reached 11,000 s [ 31 , 63 ], for grafted copolymer of chitosan and poly(N, N-diethylacrylamide) (CS- g -PDEAA) it did not exceed 9000 s [ 10 ], and for copolymer with polyimide backbone and poly(N,N-dimethylaminoethyl methacrylate) side chains (PI- g -PDMAEMA) time t eq (max) ~ 10,000 s [ 63 ]. Note that the molar masses M of the compared samples differed strongly.…”

“…Consequently, there were two types of scattering objects with hydrodynamic radii R h-f (particles responsible for the fast mode) and R h-s (particles responsible for the slow mode). The existence of two or even more types of species in solutions of stimulus-sensitive molecular brushes was observed quite often [ 8 , 9 , 10 , 11 , 63 , 64 , 65 ], and the size and fraction of various particles depended on the grafting density of side chains, their length, and hydrophilic–hydrophobic balance, as well as on the polymer concentration and the medium acidity. In the case of the studied solutions, the radii R h-f and R h-s increased with dilution ( Figure 5 ), which probably reflects the concentration dependence of the translational friction coefficient f [ 66 , 67 , 68 , 69 ].…”