Investigatory Project 2010

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RESEARCH PLAN

a. Materials and Methods The materials used were vinegar (4.5% acidity) as the amylopectin-breaker, pure liquid propan-1,2,3-triol (commonly known as glycerol or glycerine) as the plasticizer, breadfruit flesh as source of the starch, food coloring as color enhancer, distilled water, beakers as containers, graduated cylinder in measuring the accurate amount of liquid, grater to reduce the size of breadfruit, sinamay cloth as strainer, blending machine, triple-beam balance in measuring weights of samples, stopwatch in measuring the length of time intervals, stirring rods, spatula, iron stand, wire gauge, iron ring, alcohol lamp and a mini-oven toaster as drier. The research methodology included two parts, namely: (1) the extraction of breadfruit starch, and (2) the making of the bioplastic out of breadfruit starch. 1. Extracting the Breadfruit Starch The method used in extracting the breadfruit was a simple similar process used in industries to extract starch. The same single method was utilized for all replications without alteration. Freshly fallen breadfruits that were mature enough (not ripe) were chosen for the purpose. Ripe breadfruits were found to hold less starch than unripe mature ones (Udio, et.al, 2003) and breadfruits that were freshly harvested or not yet stored for 9days have more carbohydrate (starch) substance by 70.2% than 59.4% content after the ninth day of storage (Amusa, et.al, 2002). The breadfruit was then washed and peeled. Defected fleshes of the fruit were separated and discarded. A sufficient amount of the chosen flesh was grated and measured to reach 100g on a triple-beam balance as required for each replication. The measured flesh was then subjected to careful blending with 100-mL water in a blending machine just enough to barely reduce a little the size of its pieces. The mixture was then strained using a sinamay cloth.

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Another 100-mL of water was added to the solid particles and was strained twice more. The filtrate was drained using a beaker and was left to settle completely for a maximum of three (3) hours. The water was decanted from the beaker leaving behind the white starch that settled in the bottom. The starch was washed by adding 100-mL distilled water, gently stirred and left to settle again for thirty (30) minutes. The water was decanted leaving the starch behind. The wet starch was poured on a transparent spot plate and left to completely dry under the sun. The time allotted for the complete drying process was dependent on the availability of sunlight. Completely drying the starch was necessary for the accuracy in measuring the mass needed in making the plastic. 2. Making the Plastic Twenty-five (25) mL of distilled water was poured into a 250-mL beaker. Two (2) grams of breadfruit starch were added to the water and labeled as T1. Five (5) mL of vinegar (4.5% acidity) was added to break down the branched amylopectin into a straight chain which was necessary to enable the starch to form a plastic film. About 2mL of propan-1,2,3-triol was also added to the treatment. The propan-1,2,3-triol (glycerol) would make the plastic become more softer and more flexible. Without or insufficient amount of it would make the plastic harder and stiffer but more brittle (www.instructables.com). The mixture was heated using an alcohol lamp and was constantly stirred. A pinch of food coloring was added into the treatment to enhance the color of the plastic. When the mixture started to thicken up, it was stirred even more. The mixture was carefully kept on boiling gently for 10-15 minutes until a clear and sticky substance was achieved in the sample. The mixture was then poured onto each sheet of aluminum foil and was pushed around to have even coverings. The mixture was dried in an oven set to 60 C (140 F) for 1-2 hours. After the plastic was dried, it was left to cool and was then removed from the foil. The same procedure and measures were followed with T2 using commercial pure corn starch instead of breadfruit starch as the control.

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b. General Procedure/Treatment There were fifteen (15) replications and two treatments for each replication, where: T1 T2 Breadfruit Starch-Based Plastic Corn Starch-Based Plastic

Immediately, the plastic products from the two treatments were subjected to a pull-andmeasure method test using a ruler to test their tensile strength. The plastic was held hanging beside a ruler that measured its length. The plastic was then pulled and dragged through the millimeter calibrations of the ruler until a sign of breakage was observed. The initial length was subtracted from the final length both in millimeters and recorded as the measure of the tensile strength. This method is improvised due the unavailability of a Universal Testing Machine. The next test was on the comparison of the texture and hardness between the breadfruit plastic and the one made out of corn starch. Ten (10) panelists were randomly selected from Sta. Paz National High School and were allowed to rate the plastic as to their texture and hardness based on their senses, using the scale of 1 5, where 1 as excellently smooth or excellently

soft and 5 as very rough or very hard (please see Appendix C on page viii). The last test conducted was the biodegradability test wherein the samples were soaked in water for about 3 days and were observed for signs of decomposition and disintegration. Biodegradability test was based on the counting of the number of pieces that disintegrated from the main body of the plastic.

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INTRODUCTION a. Background of the Study One of the major problems that societies around the world are facing in this modern era is the seemingly perpetual problem concerning on environmental conditions. Along with the progress and all of the positive breakthroughs appear the equally conspicuous and lingering effects to the environment that oblige us to ponder and to reconsider. Pollution deranges the balance in nature and put the entire biosphere in great peril. The latest environmental crisis with this concern is the disturbing increasing rate of global warming that is being predicted by scientists to inflict terrifying catastrophes in the future that are beyond human expectations if the problem remains unsolved. One of the causes of this vast trouble is the invention that man since his discovery of it has ever been using and grateful about plastic.

Most of the stuffs that we find beneficial in our mundane life, ranging from simple utensils and garments to the most complex electronic devices and from handy lenses to massive automobile bodies, are entirely or partly made up of plastic. As more and more plastic materials are utilized, more plastic waste is produced. Most plastics in industries and home are petroleum-based. Due to the reason that petroleum plastics do not readily decompose, this waste contributes considerably to environmental pollution. Since plastics are indispensable to our modern way of life, scientists thought of some alternatives that would answer the issue on the degradability of plastics. In the 1970 s, they introduced biodegradable plastics that break down through the actions of microorganisms. Scientists also created photodegradable plastics that break down through long exposure to sunlight (World Book, 1992). Latest innovation to minimize, if not to eliminate, the problem is the making of biodegradable bioplastics. According to the study conducted by the European Bioplastics and the European Polysaccharide Network of Excellence (EPNOE) as cited by de Guzman (2009), an estimated substitution potential of up to 90% of the total consumption of plastics by bio-based polymers are technically possible.

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Bioplastics are chiefly obtained out of organic plant material. Some plant starches are now known to form plastics. One of the well-known sources of bioplastics is corn starch. Corn is converted to plastics over a series of reaction steps which start with its starch. The end-product is a high-quality plastic called polyactic acid, or PLA (eHow.com). Starch-based PLA is used in packaging and other related purposes and decomposes in time, thus, not adding to the world s plastic-related pollution. Since the demand for biodegradable starch-based bioplastics is accelerating, the search for more potential plants that can become a source of this type of plastic is also heightened. Among the plants that are known to contain significant amount of starch is breadfruit. As cited from the study conducted by Udio, et.al (2003) on the chemical analysis of the breadfruit, the edible pulp of the fruit has a high content of starch along with the core and the peel that also contain certain amounts (http://www.medwelljournals.com). Parkison (1984) as cited by Amusa, et.al (2002) also claimed that due to the high amount of carbohydrates and starch contained in breadfruits, it can easily replace such carbohydrate-rich fruits like banana, though its hydrolysable carbohydrates are thought to be higher (http://www.academicjournals.org). The Philippines as a tropical country is one of the growers of this tree (Wikipedia.com). All over the country, breadfruit either grows in the wild, domestic backyards or in plantations. Due to the massive size of the fruit, it sometimes fall from the tree even when not ripe or over-mature because of strong wind, weak attachment, plant disease, infestation and by other incidents and left forsaken on the ground to rot and be wasted. The aim to help the problem on pollution brought by the use of petroleum-based plastics by producing another starch-based bioplastic from breadfruit that is significantly biodegradable and is comparable with the proven corn-starch-based plastic, and to provide an alternative utilization of fallen breadfruit that is destined to be wasted by testing its feasibility as a component of bioplastics moved the researchers to conduct