Starch nanocrystal-reinforced

Angellier, H., Boisseau, S.M., Lebrun, L., Dufresne, A. Processing and structural properties of waxy maize starch nanocrystals reinforced natural rubber. J. Macromolecules. 38, 3783-3792 (2005a)... 

Kristo, E., Biliaderis, C.G. Physical properties of starch nanocrystal-reinforced pullulan films. Caibohydr. Polym. 68, 146-158 (2007)... 

Preparation of starch nanocrystal-reinforced NR nanocomposites is often by the solution mixing method. The general steps are depicted as follows the first step is preparation of starch nanocrystals. Starch nanocrystals were usually extracted from natural starch crops (such as maize,cassava, potato, wheat, eZc.) by hydrolysis in the presence of strong acids (such as sulfuric acid or hydrochloric acid).The second step is the mixing of the starch nanocrystal... 

Nanocomposites formed from a NR latex were filled with an aqueous suspension of waxy maize starch nanocrystals and morphology, structure and barrier properties characterized. The materials were measured in linear and nonlinear viscoelastic regions. Starch nanocrystals reinforced the NR to a content of 20 % w/w without significant loss of ultimate strain. The NR modulus was greatly increased when nano-starch was present. Starch-starch interactions were important for enhancing the composite properties. Moisture and starch nanocrystal surface chemistry were important influences on properties." ... 

Angellier H, Molina-Boisseau S, Lebrun L et al (2005) Processing and structiual properties of waxy maize starch nanocrystals reinforced natural rubber. Macromolecules 38 3783-3792 Angellier H, Molina-Boisseau S, Dole P et al (2006) Thermoplastic starch-waxy maize starch nanocrystals nanocomposites. Biomacromolecnles 7 531-539... 

Zheng Hua, Ai Fujin, Chang R. Peter, Huang Jin, and Dufresne Alain. Structure and properties of starch nanocrystal-reinforced soy protein plastics. Polym. Compos. 30 no. 4 (2009) 474-480. 

Zheng H, Ai F, Chang PR, Huang J, Dufiesne A (2009) Structure and properties of starch nanocrystal-reinforced so y protein plastics. Polym Compos 30 474—480... 

The reinforcing effect of starch nanocrystals was attributed to strong filler/matrix interactions due to the hydrogen bonding. The decrease of the permeability suggests that the nanocrystals were well dispersed, with few filler/filler interactions. 

NR composites and nanocomposites can be fabricated by three main techniques, namely latex compounding, solution mixing and melt blending. A variety of nanofillers, such as carbon black, silica, carbon nanotubes, graphene, calcium carbonate, organomodified clay, reclaimed rubber powder, recycled poly(ethylene terephthalate) powder, cellulose whiskers, starch nanocrystals, etc. have been used to reinforce NR composites and nanocomposites over the past two decades. In this chapter, we discuss the preparation and properties of NR composites and nanocomposites from the viewpoint of nanofillers. We divide nanofillers into four different types conventional fillers, natural fillers, metal or compound fillers and hybrid fillers, and the following discussion is based on this classification. 

Waxy maize starch nanocrystals appeared to be an effective reinforcing agent for NR at temperatures higher than the glass transition temperature of the... 

The Mullins effect is characterized by stress softening. In order to demonstrate the presence of the Mullins effect in NR nanocomposites, three successive tensile cycles were performed for each sample. For the unfilled NR matrix, curves corresponding to the successive cycles were perfectly superposed, to a few per cent (6-8%) (Figure 14.22(a)).For nanocomposites, a significant decrease in G o can be observed between the first and the second cycle, for films reinforced with 30 wt% starch nanocrystals (Figure 14.22(b)).Similar to the Payne effect, the magnitude of the Mullins effect also increases with filler content. Furthermore, this increase was almost proportional to the filler content. 

The reinforcing effect of starch nanocrystals was compared to the one of other fillers for NR pubhshed in the literature such as clays, organoclays, carbon black, fly ash and chitin whiskers. 

Starch nanocrystals were used to reinforce a non-vulcanised NR matrix. The NR was not vulcanised to enhance biodegradability of the total biocomposite. Non-linear dynamic mechanical experiments demonstrated a strong reinforcement by starch nanocrystals, with the presence of Mullins and Payne effects. The Payne effect was able to be predicted using a filler-filler model (Kraus model) and a matrix-filler model (Maier and Goritz model). The Maier and Goritz model showed that adsorption-desorption of NR onto the starch surface contributed the non-linear viscoelasticity. The Kraus model confirmed presence of a percolation network. ... 

The potential use of starch nanocrystals as a reinforcing phase in a polymeric matrix has been evaluated from a mechanical point of view in several publications. 

LeCorre D, Bras J, Dufresne A (2011) Evidence of micro- and nanoscaled particles during starch nanocrystals preparation and their isolation. Biomacromolecules 12 3039-3046 Lee KY, Tang M, Williams CK, Bismarck A (2012a) Carbohydrate derived copoly(lactide) as the compatibilizer for bacterial cellulose reinforced polylactide nanocomposites. Compos Sci Technol 72 1646-1650... 

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