Fiber-reinforced polymers natural fibers

Polymer composites reinforced with natural fibers have received considerable attention. Polysaccharides have attracted the attention of scientists and... 

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. 

The demand for better fuel efficiency based on the strict governmental regulations on safety and emission has led to the wide application of composites and plastics in the automotive industry in the place of the traditionally used steels [32]. Thermoplastic materials reinforced with natural fibers have reported to have excellent mechanical properties, recycling properties, etc. [33-36]. Several natural and biorenewable fibers such as wheat, isora, soybean, kenaf, straw, jute, and sisal are used in the fiber/plastic composite industry, and the use of namral fibers as reinforcements for composite has attracted many industries [37, 38]. Compared to polymer resin, polymer biocomposites that are reinforced with natural fibers have many applications due to its ease of processing, comparatively lower cost, and excellent mechanical properties [39]. For more than a decade, European car manufacturers and suppliers have been using natural fiber-based composites with thermoplastic and thermoset matrices. These biocomposites and bionanocomposites... 

As in petroleum-based polymers, most of the biodegradable polymer-based blends also show partial miscibility within their blends. In the miscibility perspective, this heterogeneous nature makes biodegradable polymer blends comparable with particulate-filled and fiber-reinforced polymer... 

Biagiotti J, Fioii S, Torre L, Lopez-Manchado MA, Kenny JM (2004) Mechanical properties of polypropylene matrix composites reinforced with natural fibers a statistical approach. Polym Compos 25(l) 26-36... 

The mechanical properties of fiber-reinforced polymer composites are cmitroUed by factors such as nature of matrix, fiber—matrix interface, fiber volume or weight fraction, fiber aspect ratio, etc. Due to the hydrophilic nature, the fibers pulled out from polyester and polyethylene matrices, they were compared with the fibers pulled out from the epoxy matrix, which carry polymer particles on their surfaces. On the other hand, fracmre of the fibers occurs at the crack plane in phenolic composites. From SEM microstructures of different composites, it was observed that the bonding of sisal fiber with the four matrices are found to be in the order of phenolic > epoxy > polyester > polyethylene [58, 59]. 

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... 

Lignocellulosic polymer composites refer to the engineering materials in which polymers (procured from natural/petroleum resources) serve as the matrix while the lignocellulosic fibers act as the reinforcement to provide the desired characteristics in the resulting composite material. Polymer composites are primarily classified into two types (a) fiber-reinforced polymer composites and (b) particle-reinforced polymer composites. Figure 1.5 (a) shows the classification of polymer composites depending upon the type of reinforcement. 

O. Faruk, A.K. Bledzki, H.P. Fink, and M. Sain, Biocomposites reinforced with natural fibers 2000-2010. Prog. Polym. Sci. 37, 1552-1596 (2012). 

Polymers Reinforced with Natural Fibers for Construction Applications... 

Table 19.1 Different published results of polymers reinforced with natural fibers for construction apphcations.

Durability of Polymer Reinforced with Natural Fibers... 

The investigations mentioned above, are focused principally on the processing and mechanical response of polymers reinforced with natural fibers, without considering that their mechanical properties decrease after exposition to alkaline environmental of cement materials or weather. Natural fibers reduce their mechanical properties after exposition to alkaline environment of the cement matrix, nevertheless the use of polymeric matrix as a binder aroimd the natural fibers provides protection for them. However, if the interface of composites is not good, and/or matrix is not alkaline resistant, hydration products like calcium hydroxide will migrate to interface, and polymer composite will deteriorate. Several studies have demonstrated that the mechanical properties of natural fibers decrease after exposure to alkaline environment of the cement matrix due to three different mechanisms [30-39] ... 

On the other hand, polymer reinforced with natural fibers for construction applications could be classified according to its application as structural or nonstructural composite. A structural natural fiber composite can be defined as one that is needed to carry a load in use. Structural panels and unit beams [21], roof systems [22] and in some cases wood and engineered wood products [10, 22], are examples of structural composites. Performance of structural composites ranges broadly from high-performance to low-performance materials. As mentioned above, polymer reinforced with natural... 

A. Hassan, A. A. Salema, EH. Ani, and A.A. Bakar, A review on oil palm empty fruit bunch fiber-reinforced polymer composite materials. Polym. Compos. 31,2079-2101 (2010). R.R. Franck (Ed.), Bast and Other Plant Fibres, p. 397, CRC Press, Boca Raton, FL (2005. A.K. Bledzki, V.E. Sperber, and O. Faruk, Natural and wood fibre reinforcement in polymers, in Rapra Review Reports, Volume 13, pp. 1-144, iSmithers Rapra Publishing (2002). C. Baillie (Ed.), Green Composites Polymer Composites and the Environment, p. 308, Woodhead Publishing Limited, Cambridge, UK (2004). 

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