Third Day Poster Session, 17 June 2010 - NanoTR-VI

More documents

Recommendations

Info

Poster Session, Thursday, June 17 Theme F686 - N1123 Preparation and Characterization of Corn Zein Nanocomposite Films for Food Packaging Applications Il KURTULU 1 , Onur ÖZÇALIK 1,2 and Funda TIHMINLIOLU 1,2,* 1 Department of Chemical Engineering, zmir Institute of Technology, zmir 35430, Turkey 2 Materials Science and Engineering Interdisciplinary Master’s Programme , zmir Institute of Technology, zmir 35430, Turkey Abstract – Potential of novel corn zein-nanocomposite (CZNC) stand-alone films for gas and water vapor barrier applications in food packaging was investigated. Nanocomposites were prepared by dispersing organomodified layered silicate (OMLS) nanoclays within corn zein biopolymer matrix utilizing solution intercalation and melt intercalation methods together. Characterization results showed exfoliated structures of nanoclays within the zein matrix. Improvements in mechanical, thermal and water vapor barrier properties due to exfoliated nanoclays were obtained. Biopolymers offer a noticeable potential of replacing conventional petroleum based polymers in food packaging materials. In the last decades extensive research on biobased materials have been conducted and today biopolymer applications began to be used instead of conventional polymers in the industry. Recent advances in nanotechnology and nanocomposite applications are also remarkable and attractive for biopolymer materials. Food packaging holds an indispensable part of modern life. As distinct from the past, most of the food products used today are being consumed far from their origin and also after months as well for most of the products. Since introduction of cheap and useful thermoplastics such as polyethylene and polypropylene in 1950s, polymers replaced conventional packaging materials such as glass or metal and introduced new solutions and high standards for food packaging. Today the amount of polymeric food packaging waste generated is a serious problem. The amount of waste generated is huge, and recovery of polymeric materials is very low even compared to glass and metal packaging wastes. For example, in the case of polypropylene; which is used in single and multi-layer packaging with other polymers so characterized as a material hard to separate and identify in the waste; the recovery ratio is just about 0.25% according to EPA 2006 statistics [1]. Advances in the biopolymeric materials field, which are capable of complete degradation in the nature, made biopolymers advantageous alternatives over non-degradable conventional polymers. Protein based biopolymers including corn zein can be processed in to films and have excellent barrier to gases and moderate barrier to water vapor. Characteristic disadvantages of biopolymers such as low mechanical strength and dependency of their characteristics to moisture should be improved by utilization of nanocomposite applications that draw attention in many fields of material science. Nanocomposite applications enabled researchers and industry to produce a new era of polymeric composite materials with enhanced mechanical, barrier, thermal and functional properties. Ordered dispersion of nano-sized particles, named exfoliated structures, lead to significant improvements in polymer properties that can not be achieved by conventional composites. Although there are some studies concerning the utilization of nanocomposite applications of protein based polymers such as wheat gluten and soy protein [2,3,4], to our knowledge there is no study related to corn zein nanocomposite films. In this study, novel corn zein nanocomposite stand-alone films were developed to examine their feasibility with varying nanoclay content as an alternative food packaging material for barrier needs. The (OMLS) content of the samples was changed from 0% to 5% (weight clay/weight corn zein). Desirable barrier properties of zein films were enhanced by using two widely used nanocomposite production techniques; solution and melt intercalation; together. First solution intercalation method was used in the preparation of the samples. Sonication was utilized for the dispersion of OMLS nanoclays within the corn zein biopolymer chains. Then the prepared solution was poured in to icy water and corn zeinnanocomposite precipitates were collected and kneaded after they dry in an oven with controlled humidity. In the later part of the preparation, a twin-screw extruder suitable for nanocomposite applications with L/D ratio of 40 and 10 heating zones integrated with a granule blade was used to process the organoclay intercalated precipitates in to granules. Finally, the nanocomposite compounds were pressed in hot press (Carver) in order to obtain the films to be cut in the required dimensions for the analysis. Results of the study showed good dispersion of nanoclays, predicted as successful intercalated and exfoliated structures depending on the clay content characterized by XRD analysis. Mechanical tests showed increased Young Modulus in CZNC and decreases in elongation at break values as was reported by many researchers for nanocomposites. The water vapor permeability of the CZNC showed significant decreases depending on the clay content. Enhanced properties in characterized films are believed to be due to the presence of ordered dispersed clay nanoparticle layers with large aspect ratios and good interaction of clays with corn zein chains in the polymer matrix. *Corresponding author: fundatihminlioglu@iyte.edu.tr [1] Marsh , K., Bugusu, B., 2007. “Roles, Materials, and Environmental Issues”, Journal of Food Science. Vol. 72, pp. 39-55 [2] Chen, P. and Zhang, L., 2006. “Interaction and Properties of Highly Exfoliated Soy Protein/ Montmorillonite Nanocomposites”, Biomacromolecules,7 (6), pp. 1700-1706 [3] Yu, J., Cui, G., Wei, M., Huang J., 2007, “Facile Exfoliation of Rectorite Nanoplatelets in Soy Protein Matrix and Reinforced Bionanocomposites Thereof”, Journal of Applied Polymer Science, Vol. 104, 3367–3377 [4] tunc, S., Angellier, H., Cahyana, Y., Chalier, P., Gontard, N., Gastaldi, E., 2007, “Functional properties of wheat gluten/montmorillonite nanocomposite films processed by casting”; Journal of Membrane Science, Vol.289, pp.159– 168 6th Nanoscience and Nanotechnology Conference, zmir, 2010 737
P P to Poster Session, Thursday, June 17 Theme F686 - N1123 Thermal and Mechanical Properties of Layered Silicate Chitosan Nanocomposite Films 1 1 Hale OguzluP Pand UFunda TihminliogluUP P* 1 PDepartment of Chemical Engineering, zmir Institute of Technology, Gulbahce-Urla 35430,zmir,Turkey Abstract-This study investigated thermal, chemical, morphological and mechanical properties of layered silicate chitosan nanocomposite films. The films were prepared by solvent casting method with using different clay contents. Films were characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and Transmission Electron Microscopy (TEM). Furthermore, dynamic mechanical analysis (DMA) of the films was performed and storage modulus, loss modulus, damping and glass transition temperature were measured. Mechanical properties of the chitosan composites were enhanced with the addition of clay. Melt behavior and degradation temperatures did not change significantly with addition of clay. Morphological studies showed partially exfoliated/ intercalated nanocomposites structures. In recent years, many researches have been aimed to improve biodegradable properties of polymeric materials, thus; the use of natural polymers has grown extensively. [1] Chitosan is the most abundant natural polymer found in the exoskeletons of crustaceans and insects and in the cell wall of fungi and microorganisms which is the deacetylated product of chitin, poly(N-acetyl-D-glucosamine), The disadvantage of chitosan based-materials is poor physical properties according to synthetic polymers. [2] Therefore, the reinforcing fillers such as layered silicates can be used to in order to improve physical properties of chitosan films. The most widely used layered silicates are clays having nano-scale dimensions shown in Figure 1.a Developing chitosan nanocomposites by inserting chitosan chains into interlayer of clay can improve its mechanical properties. Figure 1. (a)The crystal structure of silicate layers (b) three main morphology achievable in nanocomposites structure [3] In the generation of nanocomposites, two specific characteristics of layered silicates play an important role. The first one is the ability of silicate sheets to disperse into individual layers while the second characteristic is the probability to modify their surface chemistry through ion exchange reactions with organic and inorganic cations. [4]. Depending on the surface properties, level of dispersion and the strength of interfacial interactions between the polymer matrix and layered silicate (modified or not), three different types of polymer/layered silicate composite structure are achievable which can be seen in Figure 1.b To enhance dispersion the following experimental procedure was applied. Firstly chitosan solution was in aqueous acetic acid solution. The solution was mixed and clay solutions with various clay contents were prepared by dispersing appropriate amounts of clays. After swollen of clays, sonication process was applied Clay solutions were added slowly into the chitosan solutions. The 2 %, 4 %, 8 % and 10 % (w/w) clay chitosan solutions were obtained. The final solutions were stirred and placed into sonicator. Finally, the films were dried at 50 °C 1 -1 The FTIR spectra between 600 cm-P 4000 cmP Pof the nanocomposites were recorded using Shimadzu-FTIR 8400 spectrometer. The structure of nanocomposites and the state of intercalation of the clay were characterized by Phillips X’Pert Pro MRD with Cu K radiation (=1.54 nm) under a voltage of 40 kV and a current of 40 mA. Degradation temperature of the samples were measured by differential scanning calorimetry DSC, TA instruments Q10 under nitrogen flow of 50 mL/min. Glass transition temperatures, loss modulus, storage modulus and damping of the films were measured by dynamic mechanical analyzer, TA instruments. From the XRD experiments, the basal spacing of the clays in polymer nanocomposites were determined around 2.0 nm. Partial exfoliation and intercalation of the clays were obtained. Thermal results of the composites were tabulated in In Table 1. The endothermic peaks indicate the water loss, while exothermic peaks indicate the degradation temperatures of polymer and polymer nanocomposites. Degradation temperatures of chitosan based nanocomposites were lower than the degradation temperature of pure chitosan. Moreover, the mechanical properties were improved with the addition of clay. Table1.Thermal properties of pure chitosan and chitosan/clay nanocomposites Endothermic Peak Exothermic Peak Samples °C (DRminR) °C (DRmaxR) Pure CS 123.85 297.56 CS/2 wt % clay 125.55 282.13 CS/4 wt % clay 121.89 268.42 CS/8 wt % clay 129.26 286.28 CS/10 wt % clay 124.50 283.89 In conclusion, the results of the study showed that good dispersion of clays, predicted as partially exfoliated and intercalated morphology depending on the clay content as characterized by XRD and TEM. The improvement in mechanical properties of the nanocomposites was obtained. The thermal properties of the nanocomposites films did not change significantly with the addition of the clay. *Corresponding author: HTfundatihminloglu@iyte.edu.trT [1] M. Kolybaba et al. Science ,297, 5582, (2002) [2] N.V. Majeti and R. Kumar, React. and Funct. Polymers.46, 1–27 (2000) [3] G.Choudalakis and A.D. Gotsis European Poly. Journal 45, 4 (2009) [4] S. S.Ray and M. Okamotov,Progress in Polymer Science, 28, 11 (2003) 6th Nanoscience and Nanotechnology Conference, zmir, 2010 738
Page 1 and 2:
Poster Presentations 3rd Day 17 Jun
Page 3 and 4:
Poster Session, Thursday, June 17 T
Page 5 and 6:
Ultraviolet light detection charact
Page 7 and 8:
Page 9 and 10:
P P mP P vs. P = P,P P (1) P and Po
Page 11 and 12:
P P mP P vs. P = P,P P (1) P and Po
Page 13 and 14:
P P and Poster Session, Thursday, J
Page 15 and 16:
Page 17 and 18:
P P and 770 772 774 776 778 780 782
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
P 25, Poster Session, Thursday, Jun
Page 25 and 26:
P P TOBB Poster Session, Thursday,
Page 27 and 28:
P is P P is is is P,P is Poster Ses
Page 29 and 30:
U Neslihan P P P Poster Session, Th
Page 31 and 32:
Page 33 and 34:
P P Poster Session, Thursday, June
Page 35 and 36:
P Poster Session, Thursday, June 17
Page 37 and 38:
P on P via P P were P up Poster Ses
Page 39 and 40:
P ·cm. PVP P PsP P P P P and Poste
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
P Erkan Poster Session, Thursday, J
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
P P P P and Poster Session, Thursda
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
T Peptide T P P,P P,P P and TT2429T
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Page 75 and 76:
P T Additional T The Poster Session
Page 77 and 78: Poster Session, Thursday, June 17 T
Page 83 and 84: P Poster Session, Thursday, June 17
Page 87 and 88: P P Poster Session, Thursday, June
Page 89 and 90: Poster Session, Thursday, June 17 H
Page 93 and 94: P P P P P Poster Session, Thursday,
Page 105 and 106: P P P P P P Poster Session, Thursda
Page 109 and 110: P P P R2R PIN(80) P P gP P Ozlem P
Page 115 and 116: P on P P to P coordinated P Poster
Page 117 and 118: P P P P P,P P,P (P R Rm Poster Sess
Page 123 and 124: P P Institute P P Department Poster
Page 125 and 126: and P CP Poster Session, Thursday,
Page 127: P P scattering P Yusuf P P Correspo
Page 131 and 132: P P and Poster Session, Thursday, J
Page 133 and 134: P P P Poster Session, Thursday, Jun
Page 137 and 138: P P P and P (.cm). Poster Session,
Page 139 and 140: P P tilt P and P edition Poster Ses
Page 141 and 142: P P and P Poster Session, Thursday,
Page 145 and 146: P P for P for P edit. P Poster Sess
Page 151 and 152: P P ionic P P , P Poster Session, T
Page 153 and 154: P P light Poster Session, Thursday,
Page 161 and 162: P and Poster Session, Thursday, Jun
Page 165 and 166: P P Poster Session, Thursday, June
Page 173 and 174: P P Department NanoscienceT P Poste
Page 179 and 180:
Page 181 and 182:
P P P P Poster Session, Thursday, J
Page 183 and 184:
P P P Poster Session, Thursday, Jun
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
0T 0T 0T 0T As P P P P were Poster
Page 197 and 198:
Page 199 and 200:
P P P P Poster Session, Thursday, J
Page 201 and 202:
Page 203 and 204:
Page 205 and 206:
Page 207 and 208:
Page 209 and 210:
Page 211:
Poster Session, Thursday, June 17 A
show all

Third Day Poster Session, 17 June 2010 - NanoTR-VI

Create successful ePaper yourself

Delete template?

Save as template?