The Role of In Situ Crosslinked Polysiloxane/Polylactide Micro-Networks on the PLA Brittle-Ductile Transition
Year: 2026
Type: preprint
Abstract: Polylactide (PLA) has garnered significant attention as a potentially sustainable substitute for conventional petrochemical polymers. This attention is attributed to several factors, including its renewable origin, biodegradability, and its compatibility with conventional polymer processing techniques. However, its inherent fragility restricts its broader utilization as an engineering plastic. In this study, the investigation focused on the thermally activated reactive modification of PLA with two functional polysiloxanes of varying molecular architectures. This modification was explored as a toughening strategy, with the objective of promoting the brittle-to-ductile (BD) transition through the formation of a locally entangled polysiloxane/PLA micro-network within the PLA matrix. Extraction, thermal, spectroscopic, and morphological analyses were conducted to confirm the formation of a crosslinked phase. The micromechanical deformation mechanisms of pristine and toughened PLA under tension, bending, and impact forces are discussed, revealing that the dispersion level, size of dispersed phase, molecular weight, and reactivity of the introduced soft phase strongly influence rheological and mechanical performance, leading to markedly improved mechanical performance. For instance, impact strength reaches ∼37 kJ/m2 at 1 wt% MOD1 and elongation at break increases to 90% at 5 wt% MOD2.
Source: ChemRxiv
Language: English
Subfield: Biomaterials
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7212004841