DPD Study on the Interfacial Properties of PEO/PEO-PPO-PEO/PPO Ternary Blends: Effects of Pluronic Structure and Concentration

Using the method of dissipative particle dynamics (DPD) simulations, we investigated the interfacial properties of PEO/PEO-PPO-PEO/PPO ternary blends composed of the Pluronics L64(EO13PO30EO13), F68(EO76PO29EO76), F88(EO104PO39EO104), or F127(EO106PO70EO106) triblock copolymers. Our simulations show that: (i) The interfacial tensions (γ) of the ternary blends obey the relationship γF68 < γL64 < γF88 < γF127, which indicates that triblock copolymer F68 is most effective in reducing the interfacial tension, compared to L64, F88, and F127; (ii) For the blends of PEO/L64/PPO and the F64 copolymer concentration ranging from ccp = 0.2 to 0.4, the interface exhibits a saturation state, which results in the aggregation and micelle formation of F64 copolymers added to the blends, and a lowered efficiency of the L64 copolymers as a compatibilizer, thus, the interfacial tension decreases slightly; (iii) For the blends of PEO/F68/PPO, elevating the Pluronic copolymer concentration can promote Pluronic copolymer enrichment at the interfaces without forming the micelles, which reduces the interfacial tension significantly. The interfacial properties of the blends contained the PEO-PPO-PEO triblock copolymer compatibilizers are, thus, controlled by the triblock copolymer structure and the concentration. This work provides important insights into the use of the PEO-PPO-PEO triblock copolymer as compatibilizers in the PEO and PPO homopolymer blend systems.

Coarse-grained simulation of the self-assembly of lipid vesicles concomitantly with novel block copolymers with multiple tails

We carried out a series of coarse-grained molecular dynamics liposome-copolymer simulations with varying extent of copolymer concentration in an attempt to understand the effect of copolymer structure and concentration on vesicle self-assembly and stability.

Sphere-to-rod Transition of Block Copolymer in Solution Induced by Variation of Concentration

A short-chain triblock copolymer EO9-DMS7-EO9 was synthesized by couplingreaction of allyl-terminated poly(ethylene oxide) and Si–H-terminatedpoly(dimethylsiloxane). The structure and purity of synthesized copolymer wascarefully characterized. Self-assembly behavior of EO9-DMS7-EO9 triblockcopolymer in water was investigated. And it was found that along with theincrease of copolymer concentration, morphology of self-assembled aggregatestransits from sphere to rod. A plausible understanding of the morphologytransition for the investigated triblock copolymer was proposed

Sphere-to-Rod Transition of Tri-block Copolymer EO9-DMS7-EO9 in Solution

A short-chain triblock copolymer EO9-DMS7-EO9 was synthesized by coupling reaction of allyl-terminated poly(ethylene oxide) and Si–H-terminated poly(dimethylsiloxane). The structure and purity of synthesized copolymer was carefully characterized. Self-assembly behavior of EO9-DMS7-EO9 triblock copolymer in water was investigated. And it was found that along with the increase of copolymer concentration, morphology of self-assembled aggregates transits from sphere to rod.