Poly-3-hydroxybutyrate/chitosan composite films and nonwoven mats.

Composite films and nonwoven mats of the poly-3-hydroxybutyrate and chitosan natural polymers were prepared and investigated. DSC and FTIR techniques were used to confirm that P(3HB) blending with chitosan resulted in a decrease in P(3HB) crystallinity to 47% and 62% in the films and nonwoven mats, respectively. Scanning electron microscopy showed that addition of chitosan induced changes in the surface morphology of the composite films and a reduction in the diameter of ultrafine fibers in the nonwoven mats from 800 nm to 460 nm. The values of water contact angle for films (53°) and nonwoven mats (50.6°) suggested that chitosan enhanced hydrophilic properties and moisture absorption capacity of the composite materials. On the other hand, P(3HB) showed its reinforcing ability and improved the physical/mechanical properties of chitosan. The work included studies of in vitro biodegradation of the composite specimens and their ability to maintain cell growth and attachment in NIH 3T3 fibroblast culture.