Polycaprolactone-Polyaniline Blend: Effects of the Addition of Cysteine on the Structural and Molecular Properties

Author(s)

Kogikoski, Jr., Sergio ; Liberato, Michelle S. ; Factori, Irina M. ; da Silva, Emerson R. ; Oliveira, Cristiano L. P. ; Ando, Romulo A. ; Alves, Wendel A.

• Document type: Journal article
• Source: Journal of Physical Chemistry C; v. 121, n. 1, p. 863-877, JAN 12 2017.
• Web of Science Citations: 8

Abstract

Organic molecule conjugates usually arrange themselves into complex multiphase systems that are sensitive to processing and focal chemical environment. Moreover, these conjugates are able to self-assemble at different scales, varying from nano- to macroscale. In addition, intermolecular interactions introduce structural variations its the molecular packing and large-scale ordering, which directly affects different physicochemical properties of the materials. Herein, we study the synthesis of polymer blends based on poly(epsilon)-caprotactone (PCL) with polyanilirie-(PANT), doped with the amino acid N-acetyl-L-cysteine (NAC). Samples were prepared either through solution casting or via electrospinning methods. The materials were characterized regarding their morphological, structural, and, molecular properties at different length scales. From the results obtained, the relationship between changes in blend properties and different NAC concentrations was determined. Deep structural details have been unveiled by using different characterization techniques, including X-rays microcomputed tomography (Micro-CT), small- and wide-angle scattering (SAXS and WAXS), and differential scanning calorimetry (DSC). Our findings indicated that NAC enhances organization and crystallinity index of the blonds and that a close relationship appears between the synthesis method and the internal micronanostructure. It is also shown that NAC modifies the molecular properties of PANI. Through spectroscopic techniques (UV-vis and resonant Raman), it was shown that NAC favors the formation of different forms of PANI. In addition, thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) showed the formation of a supramolecular structure maintained by sulfur-pi (SH-pi) intermolecular interactions between PANT and NAC. (AU)

• FAPESP's process: 12/15481-1 - Functional polymer matrices prepared by electrospinning: Studies of structural properties and biodegradation processes
• Grantee: Michelle da Silva Liberato
• Support type: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/12674-6 - Structural investigations on model systems based on amphiphilic peptides
• Grantee: Emerson Rodrigo da Silva
• Support type: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 12/01933-8 - Biomimetic electrospun matrixes: possible application in NO detection
• Grantee: Sergio Kogikoski Junior
• Support type: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 15/24018-1 - Polymer-Peptide Conjugates for hydrogel formulation and its usage in detection
• Grantee: Wendel Andrade Alves
• Support type: Regular Research Grants
• FAPESP's process: 08/57805-2 - Institute of Bioanalytics
• Grantee: Lauro Tatsuo Kubota
• Support type: Research Projects - Thematic Grants
• FAPESP's process: 13/12997-0 - Hierarchical self-organization of peptide amphiphiles: fundamental mechanisms and potential applications
• Grantee: Wendel Andrade Alves
• Support type: Regular Research Grants