Structure, thermal and mechanical properties of poly (ε-caprolactone)/organomodified clay bionanocomposites prepared in open air by in situ polymerization

Abstract

The first example of the usefulness of titanium (IV) butoxide, as initiators for open air in-situ intercalative polymerization of ε-caprolactone (ε-CL) in the presence of organoclay is herein reported. The bionanocomposites based on poly(ε-caprolactone) (PCL) were prepared by in-situ Ring Opening Polymerization (ROP) of ε-caprolactone in the presence of different organomodified montmorillonite clay (ODA-MMT) loading (1, 3 and wt%). Structural, thermal and mechanical characterizations of the resulting bionanocomposites were investigated. The presence of the nanoclay increased PCL crystallinity, melting temperature and thermal stability, whereas some decrease in T_g was observed. TEM analyses confirmed the good dispersion of ODA-MMT with 1 and 3 wt% content into the PCL polymer as already asserted by XRD diffraction. Finally, the Young's modulus of the PCL nanocomposites was higher compared to the neat PCL, while a decrease of stress and strain at break for materials with different filler content was observed.

Graphical Abstract

Keywords:

• MMT clay
• bionanocomposites
• poly(ε-caprolactone
• )
• titanium (IV) butoxide
• in-situ polymerization

Conflict of interest

The authors declare no conflict of interest.

Additional information

Funding

Financial support for cooperative research came from the Hassan II Academy of Science and Technology of Morocco/CSIC-Spain (Project AH11STC-nano 2011 – 2012 and 2010MA003), the MESRSFC and CNRST of Morocco (PPR program), and the bilateral scientific committee programs of collaboration between Morocco and Tunisia (n° 17/TM/20), and the Spanish Ministry of Science and Innovation (MICINN) through the project MAT2016-81138-R.