Microfibrillated cellulose consists of nanoscale bundles of elementary microfibrils prepared, e.g. by the defibrillation of delignified wood pulp fibres in high-pressure homogenizers. In this study, microfibrillated cellulose was used to reinforce a thermoset starch plastic. The starch was modified with allyl glycidyl ether with a degree of substitution of 1.3, which was further hydrolyzed with α-amylase for 18 h yielding significantly improved processing properties. Dry premixes of all constituents were prepared by a stepwise drying process before sample manufacturing. The composite was cured by ethylene glycol dimethacrylate initiated with benzoyl peroxide during compression moulding at 150°C. Scanning electron microscopy revealed some degree of porosity in the samples, where the dispersed microfibrillated cellulose network was detectable. Microfibrillated cellulose, even in relatively small additions (2 wt%, 5 wt% and 10 wt%), resulted in composites with rather good hygromechanical properties. The ultimate strength increased with microfibrillated cellulose content and reached values of comparable composites with 40 wt% softwood fibre. Importantly, the dimensional stability in water was much improved compared to similar composites reinforced with substantially larger weight fractions of softwood fibres.
OrtsWJNobesGARGlennGMGregoryMGSyedIBor-SenC. Blends of starch with ethylene vinyl alcohol copolymers: effect of water, glycerol, and amino acids as plasticizers. Polym Adv Technol2007; 18(8): 629–635.
2.
ThireRMSMRibeiroTAAAndradeCT. Effect of starch addition on compression-molded poly(3-hydroxybutyrate)/starch blends. J Appl Polym Sci2006; 100(6): 4338–4347.
3.
LiaoHTWuCS. Performance of an acrylic-acid-grafted poly (3-hydroxybutyric acid)/starch bio-blend: characterization and physical properties. Des Monomers Polym2007; 10(1): 1–18.
4.
WuCS. Performance of acrylic acid grafted polycaprolactone/starch composite: characterization and mechanical properties. J Appl Polym Sci2003; 89(11): 2888–2895.
ChenJLiuCChenYChenYunChangPR. Structural characterization and properties of starch/konjac glucomannan blend films. Carbohydr Polym2008; 74(4): 946–952.
12.
MoraisLCCurveloAASZambonMD. Thermoplastic starch-lignosulfonate blends. 1. Factorial planning as a tool for elucidating new data from high performance size-exclusion chromatography and mechanical tests. Carbohydr Polym2005; 62(2): 104–112.
13.
SingletonACNBaillieCABeaumontPWRPeijsT. On the mechanical properties, deformation and fracture of natural fibre/recycled polymer composite. Composites Part B2003; 34B(6): 519–526.
14.
JoshiSVDrzalLTMohantyAKAroraS. Are natural fiber composites environmentally superior to glass fiber reinforced composites?Composites Part A2004; 35A(3): 371–370.
15.
BaleyC. Analysis of the flax fibres tensile behaviour and analysis of the tensile stiffness increase. Composites Part A2002; 33A(7): 939–948.
16.
MohantyAKWibowoAMisraMDrzalLT. Effect of process engineering on the performance of natural fiber reinforced cellulose acetate biocomposites. Composites Part A2004; 35A(3): 363–370.
PugliaDBiagiottiJKennyJM. A review on natural fibre-based composites, part: application of natural reinforcements in composite materials for automotive industry. J Nat Fib2004; 1(3): 23–65.
19.
DuanmuJGamstedtEKAndreyPRoslingA. Studies on mechanical properties of wood fiber reinforced cross-linked starch composites made from enzymatically degraded allylglycidyl ether-modified starch. Composites Part A2010; 41(10): 1409–1418.
20.
TurbakAFSnyderFWSandbergKR. Microfibrillated cellulose, a new cellulose product: properties, uses, and commercial potential. J Appl Polym Sci Appl Polym Symp1983; 37: 815–827.
21.
SiqueiraGBrasJDufresneA. Cellulosic bionanocomposites: a review of preparation, properties and applications. Polymers2010; 2: 728–765b) István Siró I and Plackett D. Microfibrillated cellulose and new nanocomposite materials: a review. Cellulose 2010; 17: 459–494.
22.
PääkköMAnkerforsMKosonenHNykänenAAholaSÖsterbergM. Enzymatic hydrolysis combined with mechanical shearing and high pressure homogenization for nanoscale cellulose fibrils and strong gels. Biomacromolecules2007; 8(6): 1934–1941.
23.
BerglundL. Cellulose based nanocomposites. In: MohantyAKMisraMDrzalLT (eds). Natural fibers, biopolymers, and biocomposites , Boca Raton, FL: CRC Press, 2005, pp. 807–832.
24.
NakagaitoANYanoH. The effect of morphological changes from pulp fiber towards nano-scale fibrillated cellulose on the mechanical properties of high-strength plant fiber based composites. Appl Phys A Mater Sci Process2004; 78(4): 547–552.
25.
NakagaitoANIwamotoSYanoH. Bacterial cellulose: the ultimate nano-scalar cellulose morphology for the production of high-strength composites. Appl Phys A Mater Sci Process2005; 80(1): 93–97.
26.
NakagaitoANYanoH. Novel high-strength biocomposites based on microfibrillated cellulose having nano-order-unit web-like network structure. Appl Phys A Mater Sci Process2005; 80(1): 155–159.
27.
DufresneAVignonMR. Improvement of starch film performances using cellulose microfibrils. Macromolecules1998; 31: 2693–2696.
28.
TimoshenkoSPGoodierJN. Theory of elasticity, 2nd ed. New York: McGraw-Hill, 1970, pp. 99–107.
29.
SvaganAJSamirMASABerglundLA. Biomimetic polysaccharide nanocomposites of high cellulose content and high toughness. Biomacromolecules2007; 8(8): 2556–2563.
30.
MaXYuJKennedyJF. Studies on the properties of natural fibers-reinforced thermoplastic starch composites. Carbohydr Polym2005; 62(1): 19–24.
31.
DuanmuJGamstedtEKRoslingA. Hygromechanical properteis of crosslinked allylglycidyl ether modified starch reinforced by wood fibers. Compos Sci Technol2007; 67(15–16): 3090–3097.
