Induced micellization and micellar transitions in aqueous solutions of non-linear block copolymer Tetronic® T904

NMR investigation of effect of dissolved salts on the thermoresponsive behavior of oligo(ethylene glycol)-methacrylate-based polymers

“…In this system above the LCST, the polymer segments tend to aggregate due to partial dehydration, which leads to attenuated motions of the backbone and side-chain segments. 23,45 Similar behavior has been observed for homopolymers of NIPAAm, however for that polymer a much more significant loss of intensity was observed on passing above the LCST. 34 In this study, the proton signals from PEMGA side chain could be clearly detected and remained relatively sharp above the LCST, indicating greater solubilization of poly(OEGMA(300)-co-TFEA) compared with PNIPAAm homopolymer at temperatures above the LCST.…”

“…The relationship between the LCST and copolymer composition for poly(OEGMA(475)-co-TFEA) in 0.5 M KCl is shown in Figure 5. The temperature is seen to depend very strongly and in a linear manner on the weight (or volume) fraction of the hydrophobic monomer, so that over the composition interval of 2-26 wt % TFEA the LCST decreases from around 73 to 45 C. The molecular weights of each copolymer are summarized in Supporting Information Table S2. Once again, these observations are in line with previous reports of the dependence of LCST on copolymer systems.…”

pH induced tuning of size, charge and viscoelastic behavior of aqueous micellar solution of Pluronic ® P104–anthranilic acid mixtures: A scattering, rheology and NMR study

“…Therefore, aggregation number is ascended. This indicates AA produced salting out effect inducing spherical to ellipsoidal micellar transition [56,57]. Hence, we conclude that the increasing concentration of AA and temperature display similar effect.…”

Glycine elicited self-assembly of amphiphilic star block copolymers with contradistinct hydrophobicities

“…Linear ABA type triblock copolymers (Pluronics ® ) comprise of poly (ethylene oxide) (PEO) and poly (propylene oxide) (PPO) blocks arranged end to end and have been extensively studied from viewpoint of their aqueous solution behaviour [4][5][6][7][8][9]. Tetronics ® , with an X-shaped structure made of an ethylene diamine central group bonded to four chains of PEO-PPO blocks are barely examined [10][11][12][13][14][15][16]. The unique structure of Tetronics ® imparts them with multistimuli responsiveness.…”

“…The decrease in pH can alter the extent of protonation of the ethylene diamine central group, perturbing the hydrophobic interaction that opposes the self-assembly process. On the contrary, higher pH neutralizes the charge on the two tertiary nitrogen atoms and promotes micellization [16,17].…”