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

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5.1f. The colloidal suspension was opaque and water retention was observed to be lower than SNF as the presence of syneresis was more apparent with quicker onset of phase separation. However, the hydrophilic nature of the fibers increasing water retention was evident during HPH processing. With each pass through the HPH, the resultant fiber suspension increased in viscosity requiring increasing amounts of water for processing. This indicated the improvement towards the individualization of cellulose microfibrils with mechanical treatment. Preliminary trials subjected SMF fibers to ultrasonic treatment to see the potential for further liberation of cellulose fibers. Dilute suspension of SMF in water was subjected to ultrasonic treatment at 40% power output. At 1-5 min, dispersion is increased along with slight evidence of gel-like matter surrounding larger fiber particles. From 5-10 min, the established dispersion is destroyed yielding aggregates with trapped air pockets that float to the surface. Increasing the length of treatment up to 20 min yielded no different results. Furthermore, applying physical pressure and shear on SMF suspensions between two surfaces expels the high amount of water retained. This yields an aggregated clump which does not readily re- disperse back in water. These findings suggest that the aggregation of fibers is highly susceptible to shear. The high energy and shear experienced by the ultrasonic treatment enhances aggregation but cannot further defibrillate the micro-sized fibers to nanometer dimensions. This aggregation behaviour of SMF’s correlates with previous trials with SNF’s whereby a broken gelled structure was re-assembled via ultrasonic treatment. 5.4.2 MORPHOLOGICAL ANALYSIS The SMF suspensions under light microscopy showed clumps of fibers bundled together (Figure 5.2). The size of some fibers can be observed in the micro range with diameters that are well below 6 µm with some lengths up to approximately 100 µm. According to the particle types 52
compiled by Moon et al. (2011), this clearly shows that the chemo-mechanical treatments successfully separated the SF to micron sizes just smaller than the MCC particle type. However, the presence of micron sized fibers denotes the inefficiency of the process towards the complete individualization of all SF to nanometer ranges. a Figure 5.2: Light optical microscopy images of SMF suspensions at low (a) and high (b) magnification. SEM images of the chemical and mechanically treated fibers throughout the extraction steps are shown in Figure 5.3. The images of both the left and right columns are of the same specimen but with different magnifications. The progressive breakdown of the soy fibers was evident, although large particles of plant material could still be observed throughout all chemical treatment steps with cell wall structures well defined. After acid hydrolysis, many holes within the cell wall structure were observed which could indicate the progressive breakdown of the structures. But any further evidence of structural breakdown was not apparent with the chemical treatments. This is in large contrast to findings reported by Alemdar and Sain (2008), whereby b 53
Page 1 and 2:
A Study on the Extrusion of Soy Pro
Page 3 and 4:
ACKNOWLEDGEMENTS My research would
Page 5 and 6:
4.3.9 Statistical Analysis.........
Page 7 and 8:
LIST OF TABLES Table 2.1: Compariso
Page 9 and 10:
Figure 5.2: Light optical microscop
Page 11 and 12: 1.0 INTRODUCTION The production of
Page 13 and 14: einforcement material. Research int
Page 15 and 16: via centrifugation into four fracti
Page 17 and 18: zones are synonymous to feeding, tr
Page 19 and 20: Ralston (2008) investigated the ext
Page 21 and 22: onding between hydroxyl groups and
Page 23 and 24: Table 2.2: Summary of cellulose par
Page 25 and 26: through the use of enzymes have pro
Page 27 and 28: matrix such as soy protein (Wang et
Page 29 and 30: 4) Explore the extraction process f
Page 31 and 32: 4.3 METHODS 4.3.1 SAMPLE PREPARATIO
Page 33 and 34: a Figure 4.2: a) Schematic of extru
Page 35 and 36: length at break by the initial grip
Page 37 and 38: 4.4 RESULTS AND DISCUSSION 4.4.1 SP
Page 39 and 40: Further experiments were carried ou
Page 41 and 42: Figure 4.5: Film with rough texture
Page 43 and 44: extrusion screw to continuously bre
Page 45 and 46: stopped which fixes the spherical s
Page 47 and 48: 4.4.3 MECHANICAL PROPERTIES Mechani
Page 49 and 50: Elongation at break (%) Figure 4.10
Page 51 and 52: Table 4.5: Water vapor permeability
Page 53 and 54: 4.4.5 FTIR ANALYSIS The main absorb
Page 55 and 56: 4.4.6 CONCLUSION The extrusion of S
Page 57 and 58: 5.3 METHODS 5.3.1 CELLULOSE EXTRACT
Page 59 and 60: For mechanical treatments, the obta
Page 61: initial soy biomass; SNF and SMF. T
Page 65 and 66: RSH: 5min HPH: 20 passes, 4000 - 60
Page 67 and 68: SMF micrographs, the presence of fi
Page 69 and 70: process as described. However, it m
Page 71 and 72: a peak at 22.6° is representative
Page 73 and 74: chemical and mechanical treatment h
Page 75 and 76: 6.3 METHODS 6.3.1 SAMPLE PREPARATIO
Page 77 and 78: 6.3.3 FILM CONDITIONING Similar to
Page 79 and 80: increased in size. At fiber concent
Page 81 and 82: 6.4.2 MORPHOLOGY AND STRUCTURE Due
Page 83 and 84: SEM images of the cryo-fractured su
Page 85 and 86: Table 6.1: Mechanical properties of
Page 87 and 88: cellulose and SPI. This high interf
Page 89 and 90: concentrations at isolated sites. A
Page 91 and 92: Similar to Section 4.4.5, dominatin
Page 93 and 94: Further analysis of the Amide II ba
Page 95 and 96: specimens that have been cryo-crush
Page 97 and 98: crushing. Conversely, this could al
Page 99 and 100: 7.0 EXPLORATORY WORK WITH TIO 2 NAN
Page 101 and 102: 7.3.2 COMPOUNDING AND EXTRUSION Com
Page 103 and 104: smaller size of P90, the ability to
Page 105 and 106: Table 7.1: Mechanical Strength of T
Page 107 and 108: Modulus of Elasticity (MPa) 120 110
Page 109 and 110: (21 nm) particle was seen to have a
Page 111 and 112: 7.4.3 MECHANICAL PROPERTIES OF TIO2
Page 113 and 114:
Tensile Strenght (MPa) 12 11 10 9 8
Page 115 and 116:
Modulus of Elasticity (MPa) 200 180
Page 117 and 118:
8.0 CONCLUSIONS AND RECOMMENDATIONS
Page 119 and 120:
The viability of introducing a comp
Page 121 and 122:
acting as a coupling agent for furt
Page 123 and 124:
Cherian BM, Leao AL, Souza SFD, Tho
Page 125 and 126:
Kacurakova M, Capek P, Sasinkova V,
Page 127 and 128:
Pääkkö M, Ankerfors M, Kosonen H
Page 129:
Wang N, Ding E, Cheng R (2008) Prep
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THESIS - ROC CH ... - FINAL - resubmission.pdf - University of Guelph

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