Study of Dynamic Rheological, Dynamic Mechanical and Creep Properties of Acrylonitrile Styrene Acrylate (ASA)/Zn⁺²poly(ethylene-co-methacrylic acid) Ionomer Blend

Abstract

A new class of blend system comprising weather resistant acrylonitrile/styrene/acrylate (ASA) terpolymer and Zn-ionomer was developed. Based on Zn-ionomer content, the blend system either forms 'mushroom' or 'brush' type conformation which affected dynamic rheology, DSC, DMA and creep properties differently. Formation of ionic crosslinkings by Zn-ionomer in 'brush regime' as well as limited ionic crosslinkings in 'mushroom regime' resulted in different nature molecular chain relaxation response. The DSC endotherm peak and glass transition temperature were also influenced by the type of conformation and ion-dipole interaction between the blend components. The tan d from DMA study also reflected the similar trend. The creep deformation behavior of the blend was found to be dependent on highly deformable Zn-ionomer content and with temperature. The Findley model analysis suggests the ionic crosslinkings may be the possible reason for controlled creep deformation of the blend.

Mechanical, rheological, and electrical properties of multiwalled carbon nanotube reinforced ASA/Na‐ionomer blend

“…The advantages of ionomer like ionic character, antistatic property, and metal adhesion have encouraged Datta et al . to study the ASA/Na‐ionomer blend and ASA/Zn‐ionomer blend . The ionomer chains are physically attached on the polyacrylate rubber phase of ASA because of similar types of chemical structure of Zn‐ionomer and Na‐ionomer.…”

“…After the critical content of ionomer, both the ASA/Na‐ionomer and the ASA/Zn‐ionomer blends transformed into “brush” type morphology, where ionomer chains formed “standing” type superstructures. The dynamic rheological measurement of both the blend systems also established this type of molecular chain conformation switchover, which was also observed by the SEM and AFM images . The mushroom and brush conformation were explained by two and three humps, respectively, in the loss modulus curves.…”

Thermal, dynamic mechanical, and creep behavior of carbon nanotube reinforced ASA/Na‐ionomer blend

“…When the ionomer content was less than 30%, the ionomer chains were present in “lying” condition on ASA matrix phase, and above 30% ionomer content (the “brush” regime), the ionomer chains were present in “standing” condition; both were verified by the scanning electron microscopy (SEM) images . Both the “mushroom” and “brush” conformations were presented pictographically in literature . The ionomer chains are grafted on the polymer backbone comprising PSAN of ASA and were designated as “Arm.” The ionic aggregates of ionomer formed ionic crosslinks in “standing” position due to the close proximity of the ionomer chains, and these ionic crosslinks divided the “Arm” into two parts—“Arm I” and “Arm II.” The “Arm I” originated from the ionic crosslink and formed free dangling arm, and the “Arm” portion between the backbone and the ionic crosslink was designated as “Arm II.”…”

“…The ASA and ionomer blend systems have been recently studied by Datta et al They investigated the mechanical and thermal behaviors, morphology, linear and non‐linear rheology, and dynamic mechanical and creep behaviors of the ASA/Na‐ionomer blend system and ASA/Zn‐ionomer blend system . Conformational transition from the “mushroom” structure to “brush” structure was observed when the ionomer content was more than 30% in the ASA/ionomer blend system.…”

“…Both the “mushroom” and “brush” conformations were presented pictographically in literature . The ionomer chains are grafted on the polymer backbone comprising PSAN of ASA and were designated as “Arm.” The ionic aggregates of ionomer formed ionic crosslinks in “standing” position due to the close proximity of the ionomer chains, and these ionic crosslinks divided the “Arm” into two parts—“Arm I” and “Arm II.” The “Arm I” originated from the ionic crosslink and formed free dangling arm, and the “Arm” portion between the backbone and the ionic crosslink was designated as “Arm II.”…”