This study focuses on the thermoformability of biopolymer films derived from corn starch and filled with montmorillonite-based nanoclay fillers. Biopolymer films with nanoclay concentrations from 0 to 5 wt% were prepared by solution casting and followed by thermoforming. The result shows that nanoclay addition improves the formability (dimensional stability and plugging property) of thermoformed specimen and also depends on the nanocomposite structure and clay concentration. Improved product stability with optimized properties was observed at 2–3 wt% nanoclay concentration due to exfoliated structure and better nanoclay particle dispersion in the polymeric matrix. Thermogravimetric analysis and dynamic mechanical analysis show maximum of 27℃ increased decomposition temperature, 12% increased storage modulus and 4℃ increased Tg at 5 wt% nanoclay-filled biopolymer film. Tensile result shows 13% increased strength, two-fold increased modulus and 29% reduced elongation for 3 wt% nanoclay-filled biopolymer series.
XieFLuckmanPMilneJ. Thermoplastic starch: Current development and future trends. J Renew Mater2014; 2: 95–106.
2.
XieFHalleyPJAvérousL. Rheology to understand and optimize processibility, structures and properties of starch polymeric materials. Prog in Polym Sci2012; 37: 595–623.
3.
BerruezoMLuduenaLNRodriguezE. Preparation and characterization of polystyrene/starch blends for packaging applications. J Plast Film Sheet2014; 30: 141–161.
4.
Alvarez-ChavezCREdwardsSMoure-ErasoR. Sustainability of bio-based plastics: General comparative analysis and recommendations for improvement. J Clean Prod2012; 23: 47–56.
5.
TangXAlaviS. Recent advances in starch, polyvinyl alcohol based polymer blends, nanocomposites and their biodegradability. Carbohyd Polym2011; 85: 7–16.
6.
WangXLYangKKWangYZ. Properties of starch blends with biodegradable polymers. Polym Rev2003; 43: 385–409.
LiuHYuLXieF. Gelatinization of cornstarch with different amylose/amylopectin content. Carbohyd Polym2006; 65: 357–363.
9.
LiMLiuPZouW. Extrusion processing and characterization of edible starch films with different amylose contents. J Food Eng2011; 106: 95–101.
10.
GasparMBenkoZDogossyG. Reducing water absorption in compostable starch-based plastics. Polym Degrad Stabil2005; 90: 563–569.
11.
Gonzalez-GutierrezJPartalPGarcia-MoralesM. Development of highly-transparent protein/starch-based bioplastics. Bioresource Technol2010; 101: 2007–2013.
12.
Da RózALCarvalhoAJFGandiniA. The effect of plasticizers on thermoplastic starch compositions obtained by melt processing. Carbohyd Polym2006; 63: 417–424.
13.
HuangM-FYuJ-GMaX-F. Studies on the properties of Montmorillonite-reinforced thermoplastic starch composites. Polymer2004; 45: 7017–7023.
14.
Schwach ESixJ-LAvérousL. Biodegradable blends based on starch and poly(lactic acid): Comparison of different strategies and estimate of compatibilization. J Polym Environ2008; 16: 286–297.
15.
MullerPKapinEFeketeE. Effects of preparation methods on the structure and mechanical properties of wet conditioned starch/montmorillonite nanocomposite films. Carbohyd Polym2014; 113: 569–576.
16.
FerreiraWHKhaliliRRFigueiraMJMJr. Effect of organoclay on blends of individually plastized thermoplastic starch and polypropylene. Ind Crops Prod2014; 52: 38–45.
DeanKYuLWuDY. Preparation and characterization of melt-extruded thermoplastic starch/clay nanocomposites. Compos Sci Technol2007; 67: 413–421.
19.
SchlemmerDAngelicaRSSalesMJA. Morphological and thermomechanical characterization of thermoplastic starch/montmorillonite nanocomposites. Compos Struct2010; 92: 2066–2070.
20.
Majdzadeh-ArdakaniKNavarchianAHSadeghiF. Optimization of mechanical properties of thermoplastic starch/clay nanocomposites. Carbohyd Polym2010; 79: 547–554.
21.
CyrasVPManfrediLBTon-ThatM-T. Physical and mechanical properties of thermoplastic starch/montmorillonite nanocomposite films. Carbohyd Polym2008; 73: 55–63.
22.
MullerCMPLaurindoJBYamashitaF. Effect of nanoclay incorporation method on mechanical and water vapor barrier properties of starch-based films. Ind Crops Prod2011; 33: 605–610.
23.
Slavutsky AMBertuzziMA. A phenomenological and thermodynamic study of the water permeation process in corn starch/MMT films. Carbohyd Polym2012; 90: 551–557.
24.
AlmasiHGhanbarzadehBEntezamiAA. Physiochemical properties of starch-CMC-nanoclay biodegradable films. Int J Biol Macromol2010; 46: 1–5.
25.
Magalhaes NFand Andrade CT. Thermoplastic corn starch/clay hybrids: Effect of clay type and content on physical properties. Carbohyd Polym2009; 75: 712–718.
26.
GaoWDongHHouH. Effects of clays with various hydrophilicities on properties of starch-clay nanocomposites by film blowing. Carbohyd Polym2012; 88: 321–328.
27.
MullerCMOLaurindoJBYamashitaF. Composites of thermoplastic starch and nanoclays produced by extrusion and thermopressing. Carbohyd Polym2012; 89: 504–510.
28.
LiuW-CHalleyPJGilbertRG. Mechanism of degradation of starch, a highly branched polymer, during extrusion. Macromolecules2010; 43: 2855–2864.
29.
Kalambur SRizviSSH. An overview of starch-based plastic blends from reactive extrusion. J Plast Film Sheet2006; 22: 39–58.
30.
DangaKMYoksanR. Development of thermoplastic starch blown film by incorporating plasticized chitosan. Carbohyd Polym2015; 115: 575–581.
31.
Jagadeesh DReddyDJPRajuluAV. Preparation and properties of biodegradable films from wheat protein isolate. J Polym Environ2011; 19: 248–253.
32.
MoralesRACandalMVSantanaOO. Effect of the thermoforming process variables on the sheet friction coefficient. Mater Des2014; 53: 1097–1103.
33.
TabatabaeiSHAjjiA. Structure-orientation-properties relationships of polypropylene nanoclay composite films. J Plast Film Sheet2011; 27: 87–115.
34.
KiliarisPPapaspyridesCD. Polymer/layered silicate (clay) nanocomposites: An overview of flame retardancy. Prog Polym Sci2010; 35: 902–958.
35.
MohanTPKannyK. Using image analysis for structural and mechanical characterization of nanoclay reinforced polypropylene composites. J Eng2010; 2: 802–812.
36.
Al-MullaEAJSuhailAHAowdaSA. New biopolymer nanocomposites based on epoxidized soybean oil plasticized poly (lactic acid)/fatty nitrogen compounds modified clay: Preparation and characterization. Ind Crops Prod2011; 33: 23–29.
37.
O’ConnorCPJMartinPJSweeneyJ. Simulation of the plug-assisted thermoforming of polypropylene using a large strain thermally coupled constitutive model. J Mater Process Technol2013; 2113: 1588–1600.
38.
ChenS-CHuangS-TLinM-C. Study on the thermoforming of PC films used for in-mold decoration. Int Commun Heat Mass Transfer2008; 35: 967–973.
39.
O’ConnorCPJMartinPJMenaryG. Viscoelastic material models of polypropylene for thermoforming applications. Int J Mater Form2012; 3: 599–602.
SalaGDi LandroLCassagoD. A numerical and experimental approach to optimize sheet stamping technologies: Polymers thermoforming. Mater Des2002; 23: 21–39.
42.
DrozdovADHøg LejreA-LChristiansenJC. Viscoelasticity, viscoplasticity and creep failure of polypropylene/clay nanocomposites. Compos Sci Technol2009; 69: 2596–2603.
43.
Hambir SBulakhNJogJP. Polypropylene/clay nanocomposites: Effect of compatibilizer on thermal, crystallization and dynamic mechanical behaviour. Polym Eng Sci2002; 42: 1800–1807.
44.
SunTChenFDongX. Shear-induced orientation in the crystallization of an isotactic polypropylene nanocomposite. Polymer2009; 50: 2465–2471.
45.
SalaGDi LandroLCassagoD. A numerical and experimental approach to optimize sheet stamping technologies: Polymers thermoforming. Mater Des2002; 23: 31–39.
46.
HosseiniHBerdyshevBVMehrabani-ZeinabadA. A solution for warpage in polymeric products by plug-assisted thermoforming. Eur Polym J2006; 42: 1836–1843.
47.
SharmilaTKBAyswaryaEPAbrahamBT. Fabrication of partially exfoliated and disordered intercalated cloisite epoxy nanocomposites via in situ polymerization: Mechanical, dynamic mechanical, thermal and barrier properties. Appl Clay Sci2014; 102: 220–230.
