Raw materials used in this experimental work are:• Natural fiber (Bagasse and Rice Straw).• Epoxy resin.• Hardener for Epoxy.• Sodium Hydroxide (NaOH) Alkalinesolution.
5.1BAGASSEBagasseis main use as a burning raw materialin the sugar cane mill furnaces. The lowcaloricpower of bagasse makes this a low efficiencyprocess. Also the sugar canemill managementencounters problems regarding regulations of”clean air” from theenvironmental protectionagency, due to the quality of the smoke releasedin theatmosphere. Present in 85% of bagasseproduction is burnt. Even so, there is anexcess ofbagasse.
Fig 5.1Bagasse Usuallythis excess is deposited on emptyfields altering the landscape. Approximately9%of bagasse is use in alcohol (ethanol) production.Ethanol is not just a goodreplacement for the fossilfuels, but it is also an environmentally friendlyfuel.Apart from this, ethanol is a veryversatilechemical raw material fromwhich a variety of chemicalscan be produced but again, due to the low level ofsucrose left in bagasse, the efficiency of the ethanolproduction is quite low.
With increasing emphasison fuel efficiency, natural fibers such as bagassebasedcompositesenjoy wider applications inautomobiles and railway coaches &buses forpublic transportsystem. Different volume fraction by weight of bagassefiber hasbeen mixed with matrix material and specimenwere prepared.Thecomposition for the bagasse 1 isas follows5.1.
1Composition CONTENTS PERCENTAGE Cellulose 46% Hemicelluloses 24.5% Lignin 19.95% Fats and waxes 3.5% Ash 2.4% Silica 2% Other elements 1.7% Table5.1 1 5.
2RICE STRAWRiceis a primary source of food for billions of people and one of the major cropsin the world. It covers around 1% of the earth’s surface. Statistics show that,during the period of 2010–2013, the average annual global production of ricewas 750 million metric tons with Asia region alone producing over 90% of thetotal global rice production3.Rice Straw is an inexpensivebyproduct of rice processing and is separated from rice grain during the ricemilling process. Fig5.2Itis reported that, for every ton of rice produced, about 0.23 tons of Rice strawis formed.
Rice milling is one of the most important industries in countriessuch as China, India, Indonesia, Malaysia, and Bangladesh. The incineration ofRice straw is discouraged, which in turn produces ash, fumes, and toxic gases,leading to serious air pollution. Moreover, silica is intrinsic to Rice strawand has been successfully used to enhance the mechanical properties ofcomposites. In the paddy plants of Malaysia, with a land area of approximately680,000 hectares, a total of 840,000 tons of Rice straw is produced every year.The composition of rice straw 6is as follows 5.2.
1Composition CONTENTS PERCENTAGE Cellulose 36-43% Hemicelluloses 26-27% Lignin 6.3-12.3% Ash 12-13% Table5.2 6 5.3EPOXY The large family of epoxy resins represents some of thehighest performance resins of those available at this time.
Epoxies generallyout-perform most other resin types in terms of mechanical properties andresistance to environmental degradation, which leads to their almost exclusiveuse in aircraft components. As a laminating resin their increased adhesiveproperties and resistance to water degradation make these resins ideal for usein applications such as boat building. Here epoxies are widely used as aprimary construction material for high-performance boats or as a secondaryapplication to sheath a hull or replace water-degraded polyester resins and gelcoats.
The term ‘epoxy’ refers to a chemical group consisting ofan oxygen atom bonded to two carbon atoms that are already bonded in some way.The simplest epoxy is a three-member ring structure known by the term’alpha-epoxy’ or ‘1,2-epoxy’. The idealised chemical structure is shown in thefigure below and is the most easily identified characteristic of any morecomplex epoxy molecule.The chemicalformula for epoxy10 is Fig 5.4 Epoxychemical formulaFig 5.3 Epoxy 5.4EPOXY HARDENER A hardener is a component of certain types of mixtures i.
e.amines, phenols. In some mixtures a hardener is used simply to increase theresilience of the mixture once it sets. In other mixtures a hardener is used asa curing component. A hardener can be either a reactant or a catalyst in thechemical reaction that occurs during the mixing process.
It is mixed with Epoxyby the ratio of 1:10. 5.5SODIUM HYDROXIDE (NaOH) Itis a highly caustic substance that is used to neutralizeacids and make sodium salts. It is used for Alkali treatment of fibers. It removes the unwanted soluble cellulose, hemi cellulose, pectin, lignin,etc.