Solvent-free and biocompatible multiphased organic-inorganic hybrid nanocomposites

Author(s)

da Silva, Laura C. E. ^[1] ; Germiniani, Luiz G. L. ^[1] ; Plivelic, Tomas S. ^[2] ; Goncalves, Maria C. ^[1]

Affiliation

^[1] Univ Campinas UNICAMP, Inst Chem, POB 6154, BR-13083970 Campinas, SP - Brazil

^[2] Lund Univ, Max Lab 4, POB 118, S-22100 Lund - Sweden

• Document type: Journal article
• Source: SOFT MATTER; v. 14, n. 9, p. 1709-1718, MAR 7 2018.
• Web of Science Citations: 3

Abstract

Biocompatible chemically cross-linked organic-inorganic (O-I) hybrid nanocomposites were developed using a new atoxic, simple and fast, solvent-free pathway. Poly(e-caprolactone) (PCL) and poly(ethylene glycol) (PEG), which are both biocompatible, were used as the organic moieties (at different PCL/PEG ratios), while in situ synthesized polysilsesquioxanes made up the inorganic moiety. The O-I hybrid nanocomposites' molecular structures were characterized using solid-state Si-29 NMR, TGA and ATR-IR. Results showed an unusually high condensation yield of approximately 90% and two distinct silsesquioxane structures. No traces of the remaining isocyanate groups were found. Advanced morphological characterization of the ternary O-I hybrids was performed using a combination of electron microscopy and X-ray scattering techniques such as SEM, TEM, ESI-TEM, WAXS and temperature-dependent SAXS. Results showed the occurrence of spherical nanoparticles, associated with polysilsesquioxane, and ordered network grains, associated with PCL and/or PEG chains crosslinked by silsesquioxane cages. As a consequence, a four-phased nanostructured morphology was proposed. In this model, PCL and PEG are undistinguishable, while polysilsesquioxane nanoparticles are uniformly distributed throughout a homogeneous cross-linked matrix, which shows gel-like behavior. Moreover, a mobile phase made up of unbound polymer chains occurs at the grain interface. (AU)

• FAPESP's process: 17/50274-0 - Structural characterization of multicomponent biodegradable polymeric systems by synchrotron X-ray scattering and transmission electron microscopy
• Grantee: Maria do Carmo Gonçalves
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/02414-5 - Topical and absorbable biomaterials for the local nitric oxide release
• Grantee: Marcelo Ganzarolli de Oliveira
• Support Opportunities: Research Projects - Thematic Grants