Morphology Development through an Interfacial Reaction in Ternary Immiscible Polymer Blends

Abstract

We studied the morphology development of ternary immiscible blends through an interfacial reaction between components. This phenomenon was observed in two ternary blend systems; one is composed of polyamide(6) (PA6), polycarbonate (PC), and poly[styrene-b-(ethylene-co-butylene)-b-styrene] (SEBS), and the other is composed of PA6, PC, and polystyrene (PS), where PA6 forms the continuous matrix in both blend systems. Maleinated SEBS (SEBS-gMA) or maleinated PS (PS-gMA) is incorporated with its unmodified polymer (un-SEBS and un-PS, respectively) at various ratios into the blends of PA6/PC. The blends of PA6/PC/un-SEBS and PA6/PC/un-PS show a similar phase formation in which the two dispersed polymers are stuck together in a PA6 matrix. The use of the maleinated polymers instead of their unmodified polymers in the blends of PA6/PC changes the phase formation drastically. The maleinated polymers react with amine end groups of PA6 at the interface during the melt mixing. Through this interfacial reaction, the domains of the maleinated polymers are dispersed in the PA6 matrix at about 100 nm in diameter, and at the same time the maleinated polymers encapsulate the PC domains. This means that the interfacial reaction induces the change of the formation of the domains composed of two dispersed phases. That is, the interfacial reaction changes the formation from “stack formation”, where the two dispersed polymers are stuck together, to “capsule formation”, where the PC domains are encapsulated by the other phase. Moreover, when both the unmodified and its maleinated polymers are incorporated together in a variety of ratios, the encapsulation by SEBS onto the PC domains gradually becomes incomplete as the ratio of the unmodified SEBS increases, whereas the encapsulation by PS of the PC is complete even when un-PS and PS-gMA are incorporated together. We discuss this morphology development in terms of the change of interfacial tensions between PA6 and maleinated polymers through the interfacial reaction. We assumed that the reduction of interfacial tension through the interfacial reaction is the driving force for this morphology development.

Encapsulation in Poly(ethylene terephthalate)/Polyamide-6/Phenoxy Ternary Blends

“…If a third polymer added moves to the interface between matrix and dispersed phase, and forms an encapsulating layer during melt mixing, it has potential to act as a compatibilizer. [1][2][3][4] This polymer should satisfy other prerequisites such as strengthening of the interface to become effective compatibilizer. Since simple encapsulation by third homopolymers generates two different weak interfaces between encapsulating polymer and matrix (or dispersed phase), the third must be carefully chosen to accomplish successful compatibilization.…”

A Chemo-Mechanical Model of Diffusion in Reactive Systems

“…In the bulk regions, where there is a persistently high amount of A and a lack of B and vice versa, the chemical reaction is complicated by the missing other reactant. This special kind of morphology formation was experimentally observed by [21].…”

“…Therefore we simulate here a segregating ternary system subjected to interfacial chemical reactions and phase coarsening. Such a kind of chemical reaction was experimentally studied by Horiuchi et al [21] to adjust morphologies in ternary immiscible polymer blends.…”

Toughening PA1010 with a functionalized saturated polyolefin elastomer

“…It is interesting to note that the elongation at break, MFI value and the critical content for brittle to tough transition both have extreme points at the grafting rate of 0.51%. It was reported 8,19 that the amino groups in nylon molecular chains can react with carboxyl of maleic anhydride and result in the formation of copolymer which functions as compatibilizer. This phenomenon is obviously related to the degree of such reaction.…”