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

Dongmei Liu,Lei Feng,Ye Lin,Meiyuan Yang,Xiaozheng Duan,Danping Wang,Xueying Jing

doi:10.3390/polym13172866

Abstract

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 () of the ternary blends obey the relationship < < < , 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.

Highlights

Pluronics are a non-ionic poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEOn-PPOm-PEOn, where n and m are the numbers of the repeating units PEO and PPO, respectively) triblock copolymers, known as poloxamers [1]
We found that most Pluronic copolymers are segregated into the PEO/PPO homopolymer interface, which leads to a decayed correlation between the PEO and PPO homopolymers
The effects of the PEO-PPO-PEO triblock copolymer structure and concentration on the interfacial properties of PEO/PEO-PPO-PEO/PPO ternary blends are investigated by the method of dissipative particle dynamics (DPD) simulations

Summary

Introduction

Pluronics are a non-ionic poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEOn-PPOm-PEOn, where n and m are the numbers of the repeating units PEO and PPO, respectively) triblock copolymers, known as poloxamers [1]. Recent studies on PEO-PPO-PEO triblock copolymers involve the application of Pluronics in the development and application of more complex systems. PEO-PPO-PEO triblock copolymers exhibit better biocompatibility, which promotes their application in the development of food [8,9,10] and drugs with new and improved long-circulating properties [11]. Since most of their applications are related to their interfacial properties and micelle formation, to rationally design biocompatible composite materials, it is important to better understand the interfacial properties of the blend composed by PEO-PPO-PEO triblock copolymers

Methods

Results

Conclusion