ABSTRACT Poly(lactic acid) (PLA) is a biodegradable, bioresorbable and hydrophobic synthetic polymer used in many commercial biomedical applications. In biomedical engineering, the hydrophobicity of polymers induces protein and lipid interactions, whereas hydrophilicity adds antifouling characteristics. This study focused on modifying commercial PLA using lithium tetrahydridoaluminate (LiAlH 4 ) and vinyl acetate to reduce the hydrophobicity of PLA. From gel permeation chromatography and nuclear magnetic resonance (NMR) data, it is observed that around 4% of the vinyl groups used were grafted on the modified PLA. A new bond of C═C and an increase of ─C═O groups in the modified PLA are noticed from FTIR and NMR analyses. Increased T g value suggests more crosslinking in the structures of modified PLA. T m , crystallinity and crystallite sizes are also decreased due to modifications. The reduced average water contact angle (a decrease of 6° from pristine PLA) indicates a reduction in hydrophobicity of the PLA, which may arise from a more accessible amorphous polar region. Proposed modifications could provide alternative ways to synthesize PLA‐based biomaterials applicable to tissue regeneration and the controlled release of bioactive molecules, where the hydrophobic‐hydrophilic balance is a primary concern.
Mukta et al. (Tue,) studied this question.