Development of Functionalized Polylactide Thin Films Using Poly(methylhydrogenosiloxane) Sol-Gel Process with...

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• Biobased polylactide (PLA) is a promising material but requires surface modification for advanced applications.
• Hydrophilization of polymer surfaces is crucial for improving biocompatibility and reducing biofouling.
• Developing scalable platforms for surface functionalization is essential for industrial viability.

Purpose of the Study:

• To develop a scalable method for hydrophilizing polylactide (PLA) films.
• To graft novel hydrophilic compounds onto PLA surfaces via a polysiloxane gel platform.
• To evaluate the impact of surface modification on wettability, biocompatibility, and antifouling properties.

Main Methods:

• PLA films were coated with poly(methylhydrogenosiloxane) (PMHS) via sol-gel condensation.
• Hydrophilic alkene-containing molecules (triethylene glycol monomethyl allyl and allylcarboxybetaine) were covalently grafted using hydrosilylation.
• Surface characterization included FTIR, XPS, and AFM.
• Wettability was assessed using water contact angle (WCA) measurements.
• Biocompatibility and antifouling properties were evaluated through protein adsorption, bacterial adhesion, and cytotoxicity tests.

Main Results:

• Homogeneous PMHS coating on PLA films was confirmed with low surface roughness (RMS = 0.29 nm).
• Hydrophilization significantly reduced water contact angles from 80° (native PLA) to 38° (TEGMEA-grafted) and 42° (ACB-grafted).
• Functionalized PLA films showed significantly reduced protein adsorption and bacterial adhesion.
• Cytotoxicity tests confirmed that the surface modification did not compromise PLA's inherent biocompatibility.

Conclusions:

• The polysiloxane gel serves as an effective platform for scalable surface hydrophilization of PLA films.
• Covalent grafting of hydrophilic compounds enhances wettability and provides significant antifouling properties.
• This surface functionalization strategy holds great potential for biomedical applications requiring biocompatible and non-fouling materials.