Solubility, Miscibility and Processability of Thermosetting Monomers as Reactive Plasticizers of Polyetherimide

A relatively new way to improve processability of thermoplastics is via the use of crosslinkable monomers which can act as reactive plasticizers and reduce the viscosity in the early stage of processing and then polymerize and phase separate during the final stage of processing thus recovering the original thermoplastics properties. This preliminary research aims to study the applicability of a range of allylic and epoxy monomers as reactive plasticizers of polyetherimide (PEI) in terms of solubility and processability of the monomers. Solubility parameters were calculated based on group additivity approach showed that only triallyl isocyanurate (TAIC) should be miscible with PEI. However, T g of various concentrations of PEI/TAIC blends indicated immiscibility of the system in the presence of 10wt% PEI while miscibility of the components improve with increasing PEI content. The lower T g s of the PEI/TAIC blends compared with pure PEI suggested the improvement in processability of PEI with the presence of TAIC.