Bamboo matrix

Bamboo readily absorbs water and swells. When dried it shrinks, consequently causing a loose bond at the bamboo-matrix interface which results in cracking. Therefore, the mechanism of bamboo-water interaction is very important because it will determine how bamboo will be... 

Abstract. IR pyrolysis of PAN and PAN based composites yields ordered graphitelike structure as well as several carbon nanostructures. Metal-carbon nanocomposites, in which the nanosized metal particles were introduced into the structure of carbon matrix in the course of IR pyrolysis of composite-precursor on the basis of PAN and metal (Gd, Pt, Ru, Re) compounds were prepared. The carbon phase of metal-carbon nanocomposites was shown to include different types of nano structured carbon particles. Bamboo-like CNT were observed in the structure of pyrolized at 910 and 1000°C composite-precursor based on PAN and GdCl3. At T=1200°C the solid carbon spheres with diameter in the range of 50-360 nm and octahedral carbon particles with the size in the range of 300-350 nm were observed. These nanostructured particles consist of carbon only or they include Gd nanoparticles incapsulated in carbon shell. IR pyrolysis of composite-precursor based on PAN as well as H2PtCl6 and RuC13 or NH4Re04 (Pt Ru(Re)=10 l) allows the preparation of Pt-Ru and Pt-Re alloys nanoparticles with 2[Pg.577]

Figure 10.13. Optical micrograph with crossed polars of bamboo fiber in PP matrix (xlOO). [Adapted, by permission, from Mi Y, Chen X, Guo Q, J. Appl. Polym. Sci., 64, 1997, 1267-73.]...

Lee and Wang [80] investigated the effects of lysine-based diisocyanate (LDI) as a coupling agent on the properties of biocomposites from PLA, poly (butylene succinate) (PBS) and bamboo fiber (BF). They observed that the tensile properties, water resistance, and interfacial adhesion of both PLA/BF and PBS/BF composites were improved by the addition of LDI, but thermal flow [81] was hindered due to cross-linking between polymer matrix and BF. Enzymatic biodegradability of... 

Another study regarding composites based on natural filler and a mixed polymeric matrix focuses on the effect of reprocessing on the final properties (Lou et al. 2007). In particular, PET and PP have been blended, added with bamboo charcoal, and reprocessed up to three times to obtain extruded or injection molded materials. Injection molded samples showed the best mechanical properties, and the materials added with bamboo charcoal maintained almost the same mechanical properties even after three cycles of processing. Eor this system, however, the amotmt of PET plays a vital role in determining the behavior of the final composite as if it is above 20 %, the phase separation between the PP and the PET phase is predominant on the reinforcing action of the filler. 

Interesting results were reported by Mi et al. [19]. They analyzed polypropylene filled with bamboo fibers with the addition of polypropylene grafted with maleic anhydride. The use of the agent promoting the adhesion was aimed at improving interactions between the components. In case of systems polypropylene/bamboo fibers/compatibilizer, the TCL has been formed. This was explained by higher ability to nucleation of bamboo fibers in relation to MAPP-grafted polypropylene as compared to pure polymeric matrix. 

Bamboo fiber-PP composites were prepared. The adhesion between fiber and matrix, MA-g-PP (MAH content was 0.5%) was used as a compatibilizer. A significant improvement was observed in the mechanical properties such as tensile modulus, tensile strength, and impact strength [15]. 

Attempts have been and are being made to overcome these problems with lignocellulosic reinforcement also in view of environmental and sustainability aspects. There is a vast scientific literature on this topic (cf. [1-3] for recent reviews) which cannot be reviewed here. By and large, it can be said that lignocellulosic fibers such as bast (e.g., flax, hemp, jute, ramie, kenaf, bamboo), leaf (e.g., sisal, abaca) or wood fibers can be used as reinforcement with advantages over glass reinforcement in price, density (approx. 1.5 g/cm or less), and renewability. Compared to the pristine matrix, stiffness is increased considerably while strength... 

M. M. Thwe, and K. Liao, Durability of bamboo-glass fiber reinforced polymer matrix hybrid composites. Composites Science and Technology, 63,375-387 (2003). 

Shih studied the thermal behavior of an epoxy resin reinforced with water bamboo husks fibres and powders [42]. The char yield increased from 8.9 % for the epoxy resin to 10.1-13.6 % for the composites containing 10 % bamboo fibres or powder. The results showed that the addition of bamboo powder or fibres to epoxy systems would raise the char yield of the sample, therefore could improve the flame retardancy of these materials. Similar results were obtained in the case of Phormium tenax fibres reinforced epoxy composites, containing 20 % fibres. The presence of plant fibres determined an increase of the composites thermal stability, due to the improved fibre-matrix interactions [43]. 

Another problem is the fibre-matrix bond, which is based mostly on mechanical interlocking. For example, the surface of bamboo fibres should be subjected to special treatment like sand blow to increase its roughness. 

The results of normalized strength and modulus as a function of monomer content (%) in compatibilized composites are shown in Figure 7. The strength first increased in pre-grafted LLDPE composite due to the improvement at the interface of the matrix and bamboo-fiber and then showed no trend with the addition of compatibilizer. It was clear that the p-grafted composites held good strength with the addition of 1.5%... 

Kumar, S., Choudhary, V, and Kumar, R. (2010). Study on eompatibility of unbleached and bleached bamboo-fiber with LLDPE matrix. Journal of Thermal Analysis and Calorimetry 102(3), 751-761. 

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