Morphological, barrier and mechanical properties of films from poly (butylene succinate) reinforced with nanocrystalline cellulose and chitin whiskers using melt extrusion
Nanocomposites from biodegradable poly (butylene succinate) (PBS), blended with nanofillers chitin whiskers (CHW, 1–5%) and nanocrystalline cellulose (NCC, 1–5%), were synthesized using melt extrusion. Morphological studies using transmission electron microscopy showed the dispersion of nanofillers in the polymer matrix. The nanofillers restricted the mobility of polymer chains, and promoted nucleation and recrystallization of polymer as reflected by increase in degree of crystallinity (Xc) from 65.9 to 75.6%. Addition of NCC and CHW increased the tensile strength of PBS based films from 23.2 MPa to 32.9 MPa and 43.6 MPa, respectively. Decrease in oxygen transmission rate of PBS films from 737.7 to 280 cc/m2/day was observed by adding 3% NCC, which further reduced to 23.8 cc/m2/day by adding compatibilizer methylene diphenyl diisocyanate (MDI, 4%). Water vapor transmission rate of PBS films reduced from 83.8 to 49.4 g/m2/day with 3% NCC addition and addition of 4% MDI further reduced it to 30.8 g/m2/day. This research suggested potential of NCC and CHW as nanofillers for enhancement of mechanical and barrier properties of PBS based films used in biodegradable food packaging applications.