Poly(butylene terephthalate)/clay nanocomposite compatibilized with poly(ethylene‐co‐glycidyl methacrylate). I. Isothermal crystallization

Abstract

Poly(butylene terephthalate) (PBT)/clay nanocomposite was prepared by blending PBT and commercial modified montmorillonite clays via a extruder by using poly(ethylene-co-glycidyl methacrylate) (PEGMA) as a compatibilizer (PBT/PEGMA/Clay). PEGMA and clay were also blended with PBT to prepare PBT/PEGMA and PBT/Clay, respectively. The morphology was investigated by wide-angle X-ray diffraction (WAXD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The clays were aggregated together and phase separation was observed in PBT/Clay. The clays were exfoliated in PBT/PEGMA/Clay. The equilibrium melting temperature was estimated by linear and nonlinear Hoffman-Weeks relation. The influence of the PEGMA and clay on the PBT crystallizable ability was also investigated by Avrami model and undercooling (difference between crystallization and equilibrium melting temperature). Hoffman-Lauritzen relation was used to estimate chain fold surface free energy. The exfoliated silicates cause a large number nucleus center to enhance the crystallization in PBT/PEGMA/Clay. The presence of PEGMA can react with the PBT and an increase in viscosity would reduce molecular mobility and crystallization in PBT/ PEGMA. The aggregated clays have a confinement effect on the segmental motion of PBT and hinder the crystallization in PBT/Clay.

Process–structure–property relationships in poly(butylene terephthalate) nanocomposites

“…PEGMA can chemically react with PBT and increase the viscosity to reduce molecular mobility and crystallization in PBT/PEGMA (Huang, 2008a). The exfoliated silicates provided a large number of nucleation centers to enhance crystallization in PBT/PEGMA/clay nanocomposites.…”

Crystallization in Polymer Nanocomposites

“…In a recent report, Huang suggested that the clay layers were exfoliated in the PBT matrix in the presence of compatibilizer, and this resulted in an enhanced nucleation of PBT [46,47] .…”

Mechanical and thermal properties of impact modified PBT blends and impact modified PBT nanocomposites

“…They are reported to be the materials of 21st century, possessing unique property combinations that are not found in conventional composites [1,2]. Several researchers have studied polymer-clay nanocomposites based on poly(butylene terephthalate) (PBT) [1][2][3][4][5]. Impact modification of engineering thermoplastic polymers, especially polyesters and polyamides, has received considerable attention in recent years.…”

“…Impact modification of engineering thermoplastic polymers, especially polyesters and polyamides, has received considerable attention in recent years. In this category, PBT is of significant importance because of its unique combination of properties, such as rigidity, solvent resistance, good thermal stability, good chemical resistance, and rate of crystallization and it is widely used in various applications such as electronics and engineering materials [3][4][5]. In order to obtain the desired properties, PBT has been blended with many polymers or inorganic nanoparticles, which imparts the required properties for many applications [6][7][8][9][10][11].…”