THESIS - ROC CH ... - FINAL - resubmission.pdf - University of Guelph

6.0 PART III: EXTRUSION OF SPI FILMS INCORPORATED WITH EXTRACTED SOY
FIBERS
6.1 INTRODUCTION
Application limits of protein films have always been due to their low mechanical strength
coupled with high moisture sensitivity. These inherent flaws could be eliminated with the use of
suitable reinforcing fillers to enhance material properties. A recent green alternative of fiber
reinforcement is with the use of natural cellulose fibers. By individualizing plant fibers at the
nano to micro levels, crystalline rich domains can be concentrated to increase the efficacy of
reinforcement. Nanocomposite films utilizing cellulose nanofibers have been previously reported
with promising effects on material enhancements (López-Rubio et al. 2007; Wang and Sain
2007a; Wang and Sain 2007b; Wang et al. 2006). This study investigates the use of the
previously extracted soy fibers as reinforcing fillers on extruded soy protein films to create a
completely sustainable biocomposite film. The extrusion process was examined and composite
SPI/cellulose blend films were characterized.
6.2 MATERIALS
Soy protein Isolate (SUPRO 760) as obtained from Section 4.2 was used for extrusion.
Cellulose fibers from soy pods and stems were obtained as in Section 5.0. The extracted SNF
and SMF specimens were used as reinforcing fibers. Glycerol was obtained as described in
Section 4.2.
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