Abstract:

Based on the strong hydrophobicity of polylactic acid (PLA) fiber, the surface modification of PLA fiber grafted with polyvinylpyrrolidone (PVP) was researched. The mechanical properties and structure of modified PLA fibers were characterized by the electronic universal strength testing machine, an infrared spectrometer and a scanning electron microscope. And the weight loss of fiber hydrolysis, water absorption and the grafting ratio of modified PLA fiber were determined. Results showed that PLA fiber after NaOH hydrolysis and acid hydrolysis were successfully grafted by polyvinylpyrrolidone (PVP), while PVP grafting rate of PLA fiber hydrolyzed by NaOH solution was lower than that of PLA fiber hydrolyzed by the acid hydrolysis. The water absorptions of two kinds of PLA fibers with different PVP grafting ration were obviously improved, and were 6.44 times and 8.97 times that of original PLA fiber, respectively. However, the mechanical properties of the modified PLA fiber were declined.

Key words: polylactic acid fiber, hydrophilic modification, polyvinylpyrrolidone, water absorption