Enhancing the compatibility and compost-aging behaviour of PLA/PHBV blends through functionalization

Document Type

Article

Source of Publication

Polymer

Publication Date

7-15-2026

Abstract

With the increasing need for sustainable materials, improving biodegradable polymer blends has become critical for environmentally acceptable applications. This study explores the enhancement of polylactic acid (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) blends by functionalizing PHBV to improve their compatibility, thermal properties, and biodegradation performance. DSC, TGA, FTIR, and SEM were used to comprehensively characterize the samples before and after a 44-day composting test. 1H and 13C NMR spectroscopy, complemented by diffusion-ordered spectroscopy (DOSY), were employed to assess the chemical environments and molecular mobility within the blends. Functionalization with 1,1′-carbonyldiimidazole (CDI) improved miscibility and phase homogeneity, as confirmed by SEM and FTIR analyses. NMR analysis revealed the appearance of new chemical environments associated with CDI-induced interfacial interactions, while DOSY measurements indicated distinct diffusion behaviour between functionalized and non-functionalized blends, reflecting differences in molecular mobility and blend heterogeneity. DSC results showed an increase in PLA crystallinity from 41% in the non-functionalized blend to 47% in the CDI-modified blend. TGA analysis further indicated enhanced thermal stability, with the PLA degradation temperature increasing from 344 °C to 362 °C. Post-biodegradation analysis showed that the blends retained a more ordered microstructure, with PLA chains displaying enhanced crystallization, most likely due to controlled degradation of the CDI-functionalized PHBV phase. FTIR measurements further supported this selective degradation mechanism and indicated increased degradation resistance. These findings demonstrate that CDI functionalization of PHBV improves compatibility, thermal stability, and biodegradation behaviour in PLA-based systems, highlighting their potential for biodegradable material applications.

ISSN

0032-3861

Publisher

Elsevier BV

Volume

359

Disciplines

Materials Science and Engineering

Keywords

Biodegradability, Biopolymer, NMR, PHB, PLA, Polymer blend, Polymer functionalization

Scopus ID

105039596188

Indexed in Scopus

yes

Open Access

no

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