Investigations of the 80/20 (wt/wt) PA6/ABS blends system in presence of SMA co-polymers as Reactive Compatibilizer and Encapsulated Multiwall Carbon Nanotubes (MWNTs)

Abstract

Introduction: The modification of a polymeric material with tailored properties was carried out either by blending with another polymer or by using suitable filler or by taking the advantages of both. The immiscible polymer blends were generally forming coarse and unstable phase morphology, which hamper mechanical properties of the materials. Therefore, it was essential to control and stabilize a desired type of morphology in order to generate polymeric materials with favourable properties through controlling composition, processing conditions, viscosity of the materials and can be compatibilized by using either reactive compatibilizer or filler or combination of both to reduce the interfacial tension. Methods: Keeping these aspects in mind, a novel strategy was introduced during melt-mixing of 80/20 (wt/wt) polyamide6 (PA6) and acrylonitrile-butadiene-styrene (ABS). Styrene maleic anhydride (SMA) co-polymer having 8, 14 and 50 wt% of maleic anhydride (MA) content was utilized as reactive compatibilizers for 80/20 (wt/wt) PA6/ABS blends system. Multiwall carbon nanotubes (MWNTs) were considered as a filler material to improve the stiffness and strength of the blends composites. To overcome the van der Waals’ forces of the MWNTs and achieve the uniform dispersion of the MWNTs in the blends phosphonium based modifier, namely octadecyl triphenyl phosphonium bromide (OTPB) was studied with Raman spectroscopy and transmission electron microscopic analysis (TEM). To restrict the MWNTs in one of the phase and/or at the interfaces and taking the advantages of the compatibilizer and filler, the MWNTs were encapsulated by the SMA (8, 14, 50) co-polymer. A simple solution method was adopted for the preparation of the SMA (8, 14, 50) encapsulated MWNTs. Results & Discussions: A detail morphological analysis was carried out in context to the migration of the MWNT along with a decrease in dispersed droplet size of ABS phase with varying interfacial energy differences between the matrix and the dispersed phase. The morphological observations were further substantiated by FTIR spectroscopy and DSC non-isothermal crystallization studies. To understand the morphological changes (refinement) in 80/20 (wt/wt) PA6/ABS binary blends in presence of SMA encapsulated MWNTs in context to melt-viscosity factor and thermodynamic aspect during melt-mixing. These observations were supported by the torque rheometry, FTIR analysis and TEM images. Conclusions: Dynamic mechanical thermal analysis (DMTA) concluded that all combinations enhances the storage modulus with decrease in Tg compared to the 80/20 (wt/wt) PA6/ABS blends. However, SMA encapsulated MWNTs enhances highest storage modulus, may be due to the better interfacial adhesion between filler and polymers. Hence, a novel compatibilization strategy was developed and evaluated for 80/20 (wt/wt) PA6/ABS blends using a hybrid compatibilizer involving MWNT. Keywords: PA6/ABS blends, Reactive and hybrid compatibilizers, Multi-wall carbon Nanotubes, Encapsulation Acknowledgment: Professor Arup Ranjan Bhattacharyya, MEMS and SAIF Indian Institute of Technology Bombay (IITB), Mumbai. References B.F. Jogi, M. Sawant, M. Kulkarni and P.K. Brahmankar, Dispersion and Performance Properties of Carbon Nanotubes (CNTs) Based Polymer Composites: A Review. Journal of Encapsulation and Adsorption Science, Scientific Research Publishing, 2012;(2):69–78. doi: 10.4236/jeas.2012.24010. G.S. Lohar, P.B. Tambe, B.F. Jogi, Influence of dual compatibilizer and carbon black on mechanical and thermal properties of PP/ABS blends and their composites. Composite Interfaces, Taylor and Francis, 2020;(12)1101–1136. https://doi.org/10.1080/09276440.2020.1726137. R.M. Dhajekar, B. F. Jogi and S.R. Nirantar, Preparation and Characterization of PAEK based Polymer Nanocomposites in the Presence of MMT Clay as Nanofiller to Study Tensile and Impact Properties. Materials Today: Proceedings, 2018;(5),6848–6854.