Sub-100 nm Cocontinuous Structures Fabricated in Immiscible Commodity Polymer Blend with Extremely Low Volume/Viscosity Ratio

Abstract

Sub-100 nm cocontinuous structures were prepared successfully in poly(vinylidene fluoride)/poly(Llactic acid) (PVDF/PLLA) blend with extremely low volume/viscosity ratio by melting blending. The reactive compatibilizer with poly(methyl methacrylate) (PMMA) side chains and random epoxide groups plays an important role in the formation and the size decrease of these structures. On one hand, PMMA side chains exhibit excellent entanglement with PVDF; on the other hand, the epoxide groups can react with carboxyl group of PLLA. The resultant comb-like compatibilizer exhibits greater capacity to maintain the stress balance on two sides. The repulsion state of the binary brushes enlarges the interface curvature radius, dominating the formation of cocontinuous structures.

Improvement of PLLA Ductility by Blending with PVDF: Localization of Compatibilizers at Interface and Its Glycidyl Methacrylate Content Dependency

“…By means of volume fraction calculation, it can be validated that the matrix and dispersed phases are PLLA and PVDF respectively. As shown in many reports, PVDF/PLLA is a typical immiscible blend system, exhibiting big domains and poor interface [ 8 , 15 , 36 , 37 ]. In this work, however, the interfacial adhesion between them has been enhanced remarkably due to the existence of reactive compatibilizers, which can be seen from the emulsified interface.…”

“…According to SEM, TEM and DMA results, we can describe the migration of compatibilizers and the resultant mechanical performance as follows. When the compatibilizers are blended with PVDF and PLLA, they tend to stay in the PVDF phase because of the excellent miscibility between them [ 8 , 15 , 20 , 41 , 42 , 43 , 44 ]. This is the reason for the disappearance of the PVDF glass transition peak in DMA curves (black curve in Figure 6 B) and the absence of micelles in Figure 5 A.…”

“…As a typical example, it has been blended with flexible polymers [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. In these multicomponent blend systems, phase separation always occurs due to the poor miscibility of them [ 14 , 15 ]. Both physical and chemical compatibilizations have been employed to improve the compatibility of them [ 16 , 17 ].…”

Reactive Comb Polymer Compatibilized Immiscible PVDF/PLLA Blends: Effects of the Main Chain Structure of Compatibilizer

“…It is obvious that the side chains take the critical role for the final compatibilization by the respective entanglements of each graft with the molecular chains of the component while the main chain simply bonds to the side chains to form one molecular structure [21][22][23][24][25][26]. Therefore, investigations have been focused on the length of the side chain and the graft density of the comb compatibilizers effects on the compatibilizations [27][28][29][30][31]. Attention has seldom been paid to the main chain effects on the compatibilization effects.…”

Porous Fibers Templated by Melt Blowing Cocontinuous Immiscible Polymer Blends

“…This approach leverages cocontinuous morphologies obtained by melt blending two immiscible polymers as a template for the porous structure. Cocontinuous morphologies, in which both polymers form interpenetrating continuous phases, form in immiscible binary polymer blends over small compositional windows around the phase inversion point. − On either side of the phase inversion point, droplet-in-matrix morphologies are observed where the isolated minority phase droplets are dispersed in a continuous majority phase. The phase inversion point and width of the cocontinuous composition window depend on several factors, such as the melt viscosity, viscosity ratio and interfacial tension. − By considering these factors, suitable compositions for generating a cocontinuous morphology by melt blending have been identified for many model binary polymer blends.…”