Evaluating the effect of hydroxyapatite nanoparticles on morphology, thermal stability and dynamic mechanical properties of multicomponent blend systems based on polylactic acid/Starch/Polycaprolactone

Abstract

A hybrid of hydroxyapatite (HA) nanoparticles and encapsulated triclosan (LATC) was utilized to improve the overall performance of Polylactic acid/ Starch/Polycaprolactone ternary blends. The morphological evaluations demonstrated that the starch component becomes gelatinized during the melt mixing process in the absence of LATC particles. However, once encapsulated triclosan particles were also added to the formulation, the granular structure of starch phase was retained indicating no gelatinization during the preparation process. In the case of nanocomposite samples, only 1 wt% of HA nanoparticles was found to exhibit a uniform distribution throughout the whole system whereas the higher concentrations resulted in the aggregation of nanoparticles dividing the system into HA-poor and HA-rich areas. Thermogravimetric analysis (TGA) was utilized to prove that those HA-rich areas were formed around the starch domains due to the strong chemical affinity. Moreover, TGA also showed that only 1 wt% of HA nanoparticles acts efficiently in delaying the initiation of thermal decomposition. Dynamic mechanical analysis results also confirmed that HA nanoparticles had a strong tendency to be absorbed onto the starch domains within the system. J. VINYL ADDIT. TECHNOL., 00:000-000,

Preparation and Characterization of Composite Blends Based on Polylactic Acid/Polycaprolactone and Silk

“…while a considerable decrease in the elastic modulus and tensile strength can be observed compared to neat PLA, therefore blending can modify the brittle structure of PLA. According to the data, tensile strength, and elastic modulus enhanced upon addition of 5% silk, while the elongation at break shows a decreasing trend, most probably because of the strong interactions between silk and polymer matrix, which is emanated from a lessened free-volume and restricted molecular mobility of the polymer chains. , The qualitative observations infer that the presence of silk in the polymer matrix resulted in the fragility of the composites and the elongation at break results further confirmed the observations, as the values of elongation decreased from 20 to 12.79% with an increase in silk content. In higher contents of silk (PLACLS7), elastic modulus and tensile strength both drastically decreased, which could be due to the agglomeration of silks, porous structure, and lack of affinity between the polymer and silk phases …”

Fabrication and properties of thermoplastic starch/montmorillonite composite using dialdehyde starch as a crosslinker

“…Starch has been used as a natural renewable polymer with wide applications due to its complete biodegradability, availability, modifiability and low cost. Some researchers have reported the production of biodegradable films using starch with the incorporation of advanced materials . Several results acquired are promising, as starch‐based films have been demonstrated to be odorless, colorless, tasteless, nontoxic and biologically degradable .…”

Dispersion of hydroxyapatite nanoparticles in natural rubber latex and poly lactic acid based matrices

“…However, when nanoparticle agglomerates were present in the polymer matrix, no such improvement was observed 39 . Furthermore, when adding fillers into polymer blends, the changes in thermal properties can be used to evaluate in which component of the blend the nanoparticles are localized 45 . In the current study, when HAp was added directly into the PLA solution (NRL/PLA‐D‐HAp), HAp agglomerates were observed and no change in thermal stability resulted when compared to the pure polymer.…”