Ultraviolet–Visible Spectroscopy: A Qualitative Tool to Predict Dispersion and Interphase Characteristics in Carbon-Based Particulate Filled Poly (Lactic Acid) Composites

Abstract

Abstract Properties of polymer composites depend to a large extent on the characteristics of dispersion and interphase layers. In this work, poly (lactic acid) composites (PLAC) were prepared via the dissolution–dispersion method (DD) and oligomeric–dispersion method (OD). Ultraviolet–Visible spectroscopy (UV–VIS) was used to determine the dispersion and interphase characteristics within the PLAC. An increase in absorbance at a higher wavelength within the absorbance spectra was observed for PLAC prepared by DD and OD, which can be attributed to the formation of strong adlayers as well as “near to homogenous dispersion” for carbon-based particulate filled composites. An increase in absorbance was observed for PLAC prepared by OD in comparison to DD and can be attributed to modifications occurring at interphase regions. PLAC using carbon black, multiwalled carbon nanotubes in poly (lactic acid) were prepared via DD and OD and further characterized by UV–VIS. To study the “hybrid effect,” composites with 2.5 weight percent of carbon black with varied concentration of multiwalled carbon nanotubes and nanocellulose fibers were prepared via DD and OD, further characterized for UV–VIS. This manuscript portrays the role of UV–VIS to determine dispersion as well as the interphase characteristics for poly (lactic acid) filled carbon composites.