Natural fiber composites fabrication

The purpose of the present investigation was to study the trimerization of aromatic nitriles under the conventional resin/fiber composite fabrication conditions using p-toluenesulfonic acid as a catalyst. Trimerization parameters investigated included reaction temperature, pressure, time, and concentration of catalyst. The influence of the nature of aromatic nitriles on trimerization was also studied. Also presented are preliminary results on the use of the catalytic trimerization of the nitrile-terminated imide oligomers to fabricate graphite fiber reinforced composites. 

Natural fiber (jute fabric) and industrial wastes are used along with polymer to make composite wood substitute products. In this process, processed fabric of jute fiber and industrial wastes such as fly ash/red mud/marble sluny dust with polymer were synthesized in molds of required length and width. The composite laminates were fabricated with requisite pressure and cured at room temperature. Various products such as full size door shutters and panels can be fabricated and designed according to requirement. The industrial waste-based polymer composite products are comparable to natural wood and thus could be used as a wood substitute for doors, windows, ceilings, flooring, partitions, and furniture, etc. The products are cost-effective and no further maintenance is required. This is an environment friendly product with fruitful utilization of fly ash/red mud/marble slurry dust (Table 22.14). The salient features of the products are ... 

Cotton and cellulose fibers like sisal have good high temperature properties (equal to or even above nylon). Some cotton fibers are as long as 4 in. Water removal is a problem in the use of natural fibers, but benefits including renewable resource may offset the difficulties. Polymer-coated cotton fabric is widely used in many different applications. Some excellent work on recycled wood and natural fiber composites for use in construction is being done at the USDA Forest Products Laboratory in Madison, WI. 

Seventy years ago, nearly all resources for the production of commodities and many technical products were materials derived from natural textiles. Textiles, ropes, canvas, and paper were made of local natural fibers, such as flax and hemp. Some of them are still used today. In 1908, the first composite materials were applied for the fabrication of big quantities of sheets, tubes, and pipes in electrotechnical usage (paper or cotton as reinforcement in sheets made of phenol- or melamine-formaldehyde resins). In 1896, for example, airplane seats and fuel tanks were made of natural fibers with a small content of polymeric binders [1]. 

Ultra-high modulus fibers such as aramid and carbon fibers have been currently utilized for composite material fabrication. Ultra-high modulus polyethylene (UHMPE) fiber is also applicable for composite fabrication because of the light weight in addition to its high modulus, vibration damping, and resistance to chemicals. However, this fiber has drawbacks such as poor interfacial adhesion with the polymer matrix of the composite because of highly hydrophobic nature of the fiber surface. 

The first part of this study describes a series of experiments designed to answer some of the questions on how aqueous and nonaqueous treatments alter the morphology and chemical composition of fibers taken from a Tiahuanaco tapestry. The second part of this study focuses on the colorfastness to dry cleaning of naturally colored wool fabrics. This second study was undertaken because no information on the colorfastness of these types of colorants to dry cleaning could be found in the literature. A recently published paper (3) on drycleaning of historic textiles indicates that conservators are using this nonaqueous type of cleaning as a method of textile conservation. 

In this context, nanoporous carbons are extremely interesting materials which can be used either as electrodes of supercapacitors or hydrogen reservoir. They are commercially available at a low cost and under various forms (powder, fibers, foams, fabrics, composites) [3]. They can be obtained with well-developed and controlled porosity [4,5] and with a rich surface functionality [6,7], As far as electrochemistry applications are concerned, very important advantages of carbons are a high electrical conductivity, a good chemical stability in various electrolytic media and the possibility to control wettability by the nature of the surface functionality. When they are not playing the role of active material for the storage process, carbons may be also useful as additive in a composite to improve its physical properties. Particularly carbon nanotubes are able to improve the electrical conductivity and mechanical properties of electrodes [8],... 

Mohanty AK, Parija S, Misra M (1996) Ce(IV)-A(-acetylglycine initiated graft copolymerization of acrylonitrile onto chemically modified pineapple leaf fibers. J Appl Polym Sci 60 931-937 Mohanty AK, Khan MA, Hinrichsen G (2000) Surface modification of jute and its influence on performance ofbiodegradable jute-fabric/Biopol composites. Compos Sci Technol 60 1115-1124 Mohanty AK, Misra M, Drzal LT, Selke SE, Harte BR, Hinrichsen G (2005) Natural fibers, biopolymers and biocomposites an introduction. In Mohanty AK, Misra M, Drzal LT (eds) Natural fibers, biopolymers and biocomposites. Taylor Francis, FL, Boca Raton Mukherjee PS, Satyanarayana KG (1986) Structure and properties of some vegetable fibres Part 2 pineapple fiber. J Mater Sci 21 51-56... 

Lee BH, Kim HJ, Yu WR (2009) Fabrication of long and discontinuous natural fiber reinforced polypropylene bio composites and their mechanical properties. Fibers Polym 10 (l) 83-90... 

K.G. Satyanarayana, K. Sukumaran, A.G. Kulkarni, S.G.K. Pillai, and P.K. Rohatgi, Fabrication and properties of natural fiber-reinforced polyester composites. /. Compos. 17(4), 329-333 (1986). 

In principle, woven, knitted or braided structures could also be prepared as natural fiber/PP-composites. But the higher manufacturing costs do not justify the use of these fabrics. The main reason for this is that natural fiber containing composites are low-tech and low-cost products nowadays. 

The fabrication of pol)mer composites is complex. The nature and the shape of the materials used in the fabrication are numerous and the process may differ from one application to another. In the fiber composites materials, the fibers may be discontinuous or continuous. The former may be collimated the latter may be used as preforms or prepregs with complex architectme and flow. Rheology of such materials... 

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