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

cellulose and SPI. This high interfacial interaction seen should be expected as both cellulose
and SPI have many groups to form hydrogen bonds (Chen and Liu 2008; Wu et al. 2009).
Tensile Strength (Mpa)
8
7
6
5
4
3
2
1
0
Figure 6.6: Tensile strength with respect to fiber content and relative humidity
The elastic modulus results shown in Figure 6.7 are similar to the findings seen with
tensile strength. With the increase in humidity, stiffness is decreased due to the plasticization
effects of water. This again should be caused by the hydrophilic nature of the films leading to
water absorbed. Comparing SMF and SNF fibers showed that at 43 and 58% RH, there were no
significant differences. The greatest improvement in elasticity was shown with the addition of
SMF’s at 0.25% w/w SMF/SPI. At 43% RH, the SMF0.25 specimens had a greater elastic
modulus of 85.26 ± 5.14 MPa in comparison to the control specimens at 65.55 ± 3.56 MPa.
Similar to tensile tests, notable improvement was also seen at 84% RH where SMF0.25
specimens yielded an improvement of about 20 MPa with 45.21 ± 7.72 MPa in comparison to
23.36 ± 3.45 MPa from SPI control films.
0 CNF 0.25 CF 0.25 CF 0.5 CF 1 CF 2.5
Fiber Content (% w/w SPI)
77
43% RH
60% RH
84% RH