Cellulose fiber-reinforced starch

Wan WK, Hotter JL, Millon LE, Guhados G (2006) Bacterial cellulose and its nanocomposites for biomedical applications. In Oksman K, Sain M (eds) Cellulose nanocomposites. Processing, characterization, and properties. American Chemical Society, Washington DC Wan YZ, Luo H, He F, Liang H, Huang Y, Li XL (2009) Mechanical, moisture absorption, and biodegradation behaviors of bacterial cellulose fiber-reinforced starch biocomposites. Compos Sci Technol 69 1212-1217... 

Fibers have been widely used in polymeric composites to improve mechanical properties. Cellulose is the major substance obtained from vegetable fibers, and applications for cellulose fiber-reinforced polymers have again come to the forefront with the focus on renewable raw materials. Hydrophilic cellulose fibers are very compatible with most natural polymers. The reinforcement of starch with ceUulose fibers is a perfect example of a polymer from renewable recourses (PFRR). The reinforcement of polymers using rigid fillers is another common method in the production and processing of polymeric composites. The interest in new nanoscale fillers has rapidly grown in the last two decades, since it was discovered that a nanostructure could be built from a polymer and layered nanoclay. This new nanocomposite showed dramatic improvement in mechanical properties with low filler content. Various starch-based nano-composites have been developed. 

Extensive research has been undertaken in blending different polymers to obtain new products having some of the desired properties of each component. Among protein- and polysaccharide-based green materials, those made from soy protein (Maruthi et al. 2014 Ghidelli et al. 2014 Behera et al. 2012) and starch (Katerinopoulou et al. 2014 Flores-Hemandez et al. 2014) have been extensively studied for and their physiochemical properties been analyzed. The literature review clearly shows that development of biodegradable biopolymer-based materials based on these materials can not only solve the white pollution problem but also ease the overdependence on petroleum resources. This chapter provides a brief overview of the preparation, properties, and application of cellulose fiber-reinforced soy protein-based and starch-based biocomposites. 

For instance, Soykeabkaew et al. (2004) prepared cellulose liber-reinforced starch-based composite foams (SCFs) by baking process. SCFs were prepared successfully by baking starch-based batters incorporating either jute or flax fibers inside a hot mold. Starch is an alternative material for making foams. Batters of starch and water can readily be baked in a closed, heated mold where the starch granules gelatinize and the evaporation of water causes the starch to foam out and take up the shape of the mold. Foams made from pure starch have major drawbacks on their brittleness and sensitivity to moisture and water. Since both the fibers and the starch matrix were naturally polar and hydrophilic, strong interaction between them was expected. 

Figure 9.13. SEM observation of the cryogenic fracture surface in a composite of plasticized starch reinforced with cellulose fibers (white line = 100 microns) [AVE 01b]...

Recently, bacterial cellulose, produced by Acetobacter Xylinum, was used as reinforcement in composite materials with a starch thermoplastic matrix [230]. The composites prepared with bacterial cellulose displayed better mechanical properties than those with vegetable cellulose fibers. 

Chapter 5 summarizes the investigation of lignocellulosic flax fiber-based reinforcement requirements to obtain structural and complex shape polymer composites. This chapter discusses in detail the possibility of forming complex shape structural composites which are highly desirable for advanced applications. Chapter 7 focuses on the structure and properties of cellulose-based starch polymer composites, while Chapter 8 focuses on the spectroscopic analysis of rice husk and wheat gluten husk-based polymer composites using computational chemistry. Chapter 9 summarizes the processing, characterization and properties of oil palm fiber-reinforced polymer composites. In this chapter, the use of oil palm as reinforcement in different polymer matrices such as natural rubber, polypropylene, polyurethane, polyvinyl chloride, polyester, phenol formaldehyde, polystyrene, epoxy and LLDPE is discussed. Chapter 10 also focuses on... 

However, increasing cellulose fiber content and time of photo-irradiation led to decreasing elongation (%) values. Other research on the use of thermoplastic starch without further modification (i.e., changes in experimental conditions) include the work of Lu et al. (2006), Ma et al. (2007), Fama et al. (2009), Kaushik et al.(2010), Liu et al. (2010), Guimaraes et al. (2010), and Kaith et al. (2010). These studies show a significant increase in tensile and thermal properties of thermoplastic starch when the matrix reinforced with nanofibers. 

A sketch of the tape casting process (adapted from Wonisch et al. 2011) is presented by OUveira de Moraes et al. (2013) and can be observed in Fig. 5. They obtained, through this technique, cassava—glycerol films reinforced with cellulose fibers. The results showed that tape casting is a suitable technology to scale-up the production of starch-based films. 

Orts et al. (2005) studied the properties of cellulose microfibrils obtained from different sources of cellulose fibers added at low concentrations (2-10 % w/w) to starch gels and films as reinforcing agents. Significant changes in mechanical... 

The use of traditional composites made by glass, aramid, or carbon fiber-reinforced plastics has recently been discussed critically because of increasing environmental consciousness [8]. Thus, the recent research and development (R D) efforts have led to new products based on natural resources. Some of these are biodegradable polymers like PLA, cellulose esters, polyhydroxyalkan-otes (PHAs), and starch polymers. Furthermore, natural fiber-reinforced plastics made of natural fibers like flax, hemp, kenaf, jute, and cotton fibers are important R D achievements. Composites made of natural fibers and biopolymers... 

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