Eight well-defined poly(glycidol)−poly(propylene oxide)−poly(glycidol) (PG−PPO−PG) block copolymers with PG contents from 20 to 84 wt % and fixed molecular weight of the middle PPO block of 2000 were prepared. The copolymers are considered as analogues to the commercially available Pluronic, poly(ethylene oxide)−poly(propylene oxide)−poly(ethylene oxide) (PEO−PPO−PEO), block copolymers in which the PEO blocks are substituted by blocks of linear PG. They were prepared by means of anionic polymerization of ethoxyethyl glycidyl ether (protected glycidol) followed by cleavage of the protective groups. The resulting products bear hydroxyl groups in each repeating glycidol unit. In aqueous solution all studied copolymers were found to self-associate above a certain critical concentration (cmc), which depends on the PG content and temperature. The cmc values were found to decrease with increasing temperature and decreasing the content of the hydrophilic component less strongly than those of the corresponding Pluronic copolymers. According to the thermodynamic data, the substitution of the PEO blocks by blocks of linear PG reduces the enthalpic barrier to aggregation. The latter is entropically less favored compared to that of the Pluronics. The turbidity measurements reveal three types of transmittance vs temperature curve patterns. Two of them have been observed for some Pluronic copolymers. The third type, characterized by an increase of transmittance with increasing temperature, is exhibited only by the copolymers of higher (above 50 wt %) PG content. This behavior as well as other findings that deviate from the expectations can be understood with the well-documented in the present study fact that the interactions of the constituent blocks with water change with temperature in opposite manners.

A number of diblock and triblock copolymers of ethylene oxide and 1,3-didodecyloxy-2glycidyl-glycerol (DDGG), an epoxide monomer bearing a lipid-mimetic anchor, were synthesized via anionic polymerization. The copolymers were characterized by 1 H nuclear magnetic resonance spectroscopy and gel permeation chromatography. Their self-association in aqueous environment was studied by simultaneous static and dynamic light scattering, and the particles were visualized by means of cryogenic transmission electron microscopy. The weight-average molecular weights, the radii of gyration, the second virial coefficients, the diffusion coefficients, and the hydrodynamic radii of the particles were determined. The particles were of nanodimensions with weight-average molecular weights up to tens of millions and consisted of hydrophobic poly(DDGG) and hydrophilic PEG chains in the core and corona, respectively. The results indicate formation of PEG-water domains randomly distributed in the cores. Dynamic light scattering of selected copolymers carried out in extended temperature and concentration intervals revealed a formation of dense particles. The density of the particles was found to increase with a temperature increase.

A number of ABA and BAB triblock copolymers of ethoxyethyl glycidyl ether (EEGE) and propylene oxide (PO) were prepared by sequential anionic polymerization. The copolymers were characterized by nuclear magnetic resonance and gel permeation chromatography. The total numberaverage molecular weights were in the range 1000-9000, whereas the degrees of polymerization of the PPO and PEEGE blocks varied from 2 to 34 and from 3 to 17, respectively. The copolymers were comprised of blocks with different lower critical solution temperatures (LCSTs) in aqueous media. Their selfassociation in aqueous environment was studied by cloud point (CP) measurements, dye solubilization, light scattering, 1 H nuclear magnetic resonance, and scanning electron microscopy. Although the behavior of the copolymers was found to depend on their architecture, the PO/EEGE ratio, and the degrees of polymerization of the different blocks, the role of the PEEGE blocks was decisive: it is PEEGE that determines the LCST properties of the copolymers as well as their CP and critical micelle concentration values. The copolymers form nanosized particles as revealed by light scattering. The aggregates exhibit different temperature behavior depending on the copolymer architecture. The aggregates of the copolymers of a normal, i.e., ABA, architecture were found to undergo a secondary aggregation at certain temperatures, whereas those of the BAB copolymers gradually increased in size with increasing temperature. The difference is attributed to the different arrangement of the chains in the corona regions, directly affecting the continuity and thickness of the corona.