TITLE:
Polycaprolactone and Poly(Lactic Acid) Filled with Low Content of Oxidized Carbon Nanotubes-Hydroxyapatite (o-CNT-HAp) Hybrid Filler: Effect of Proportion between o-CNT/HAp and Type of Polymer on the Properties and Interaction
AUTHORS:
Isabella Carneiro Gonçalves, Kaio Alves Brayner, Enzo Erbisti Garcia, Gerson Alberto Valencia Albitres, Luis Claudio Mendes
KEYWORDS:
Polycaprolactone, Poly(lactic Acid), Oxidized Carbon Nanotubes, Hydroxyapatite, Composite
JOURNAL NAME:
Materials Sciences and Applications,
Vol.17 No.7,
July
24,
2026
ABSTRACT: Multiwall carbon nanotubes are known as multifunctional materials due to their nanometric nature and specific physical and chemical properties. Their oxidation induces structural chemical modification leading to better interaction with polymers. In this context, it was studied the effect of low content (0.05 wt.%) of hybrid filler constituted of oxidized carbon nanotubes (o-CNT)/hydroxyapatite (HAp) at different proportions added to the sustainable polyesters-polycaprolactone (PCL) and poly(lactic acid) (PLA). Properties and polymer-filler interaction were assessed. By spin-spin relaxation times, T1 showed no expressive variation for PCL and composites while spin-lattice relaxation times revealed that T2 changed for PLA-o-CNT-HAp(2:1). Thermogravimetry showed that there was no significant alteration in thermal stability of PCL and composites but PLA-o-CNT-HAp(2:1) revealed a slight increase in thermal stability. Only PLA-o-CNT-HAp(2:1) exhibited increase of crystalline melting temperature and decrease of degree of crystallinity whereas no change was achieved for PCL composites. Owing to the low content of fillers, the rheological measurement was driven by polymer matrices. The results suggested that the chemical structure of polymer matrix and the arrangement of the hybrid fillers jointly or to some extent influenced the chemical interaction and properties of the composites.