Background of the Study
Solid waste management is increasingly seen as a major issue in the country due to high rates of urbanization and increasing per capita solid waste generation with greater affluence (Petnamsin, et al., 2000). A major component of solid waste is resin based plastic. Plastics posses many properties such as water resistance and long life, that makes them perfect candidates for packaging. Unfortunately, the properties that make this product suitable for packaging also are the major cause of the environmental problems related to packaging.
Given the wide use of plastics, the magnitude of the environmental problem is large and long terms. The choices for dealing with this waste are limited as incineration of plastic polymers invariably results in the generation of toxic emissions (Srorith, et al., 2000). The only visible solution is to bury the material in landfills. However, this approach is also limited because of the resistant nature of plastic to biological degradation.
Jackfruit Artocarpus heterophyllus Lam. is a popular fruit-crop that is widely grown in tropical areas. Often, its seeds are discarded because of the preferred well-flavored yellow sweet bulb for consumption. The seeds have high carbohydrate and protein content, hence, an abundant source of starch (Kurian, 2010). Starch is identified as a key natural product for the production of biodegradable plastic (Pranamuda, et al., 2006).
Based on the above information, the researchers decided to do research work on starch-based biodegradable plastic from jackfruit seeds. Henceforth, there is a need to establish the additive property of starch from jackfruit seeds as scientific basis for its use in the production of biodegradable plastic.
Objectives of the Study
The study will aim to find out if jackfruit Artocarpus heterophyllus Lam. seeds can be a main component in the production of biodegradable plastic. Specifically, the study will 1. determine the efficacy of starch from jackfruit A.heterophyllus Lam. seeds at varying concentrations as additives in the production of biodegradable plastic. 2. compare the mechanical properties between the produced biodegradable plastic from starch of jackfruit A.heterophyllus Lam. seeds, and commercially prepared plastic, polyethylene in terms of tensile strength, flammability, soil biodegradability and air test. 3. compare the effects of acids and bases and organic solvents between produced biodegradable plastic from starch of jackfruit seeds and commercially prepared plastic, polyethylene.
Hypotheses of the Study
The following hypotheses will be put forward:
1. There is no significant difference in the efficacy of starch from jackfruit seeds at varying concentrations in the production of biodegradable plastic. 2. There is no significant difference on the mechanical properties between the produced biodegradable plastic from starch ofjackfruit seeds and commercially prepared plastic, polyethylene in terms of tensile strength, flammability, soil biodegradability and air test. 3. There is no significant difference on the effects of acids and bases and organic solvents between produced biodegradable plastic from starch of jackfruit seeds and commercially prepared plastic polyethylene.
Significance of the Study
The results of the study would be beneficial and helpful to the manufacturing plastic industries because it would relieve negative effects of overproducing plastics. By changing its raw materials and components, commercial plastic may be improved so that it would become biodegradable while retaining its good quality. Moreover,this component from starch of jackfruit seeds would help in the natural decomposition of plastic raw materials. Thus, a convenient way of minimizing waste management problem in the country, more so, the high demand for plastics would give the world the hazard of garbage problem, therefore, utilizing starch from jackfruit seeds as component in the production of biodegradable plastics would be the relative answer.
Scope and Limitations of the Study
The study will focus only on the starch-based biodegradable plastic from jackfruitA.heterophyllus Lam. seeds. It will be conducted at the Physics/Chemistry Laboratory of Antique National School, San Jose de Buenavista, Antique from July 15, 2011 to September 30, 2011.
The variables to be evaluated will be the effect of starch from jackfruit seeds at varying concentrations for the production of biodegradable plastic; the mechanical properties between the produced biodegradable plastic from starch of jackfruit seeds and commercially prepared plastic, polyethylene in terms of tensile strength, flammability, soil biodegradability and air test;the effects of acids and bases and organic solvents between the produced biodegradable plastic from the starch of jackfruit seeds and commercially prepared plastic, polyethylene.
Analysis of Variance (ANOVA) and Duncan Multiple Range Test (DMRT) will be used as statistical tools to identify the significant differences among treatment means and their interactions at 0.01 and 0.05 levels of significance, respectively.
Definition of Terms
Biodegradable.A substance or property of the produce plastic in the study that can be broken down into simpler substances by the activities of living organisms for decomposition. Plastic. An end product obtained mainly as a result of the study using starch from jackfruit seeds as main component mixing with other components for biodegradable formation.
Starch. A complex carbohydrate extracted from jackfruit seeds and used in the study for the production of biodegradable plastic.
Polyvinyl Alcohol. An odorless, colorless, tasteless, thermoplastic synthetic resin used in the study that is soluble in water and insoluble in common organic solvents. Glycerol. A simplest trihydric and commonly called glycerin in commercial form that is used in the study for the production of biodegradable plastic.
REVIEW OF RELATED LITERATURE
After cutting talahib pulps into very small pieces, they were combined with different chemicals such as polyvinyl alcohol, sodium hydroxide in aqueous solution, glue, and glycerol to produce biodegradable plastics with different amounts of talahib pulp. (Valdez, 2009).
A study determined the effectiveness of cassava starch as component of biodegradable plastic. Results confirmed that cassava starch is ideal as tests proved its worth (Romero, 2007). It was known that starch-based packaging materials are produced from extrusion or compression technology and have been developed as a substitute for polystyrene in producing loose-filters and other expanded items. The type of starch and synthetic polymer as well as their relative proportions in the blends may influence the properties of the resulting plastics (Sriroth and Sangseethong, 2003).
Some physicochemical and rheological properties of jackfruit seed flour and starch, isolated from the flour were investigated. The flour had good capacities for water absorption and oil absorption. Flour from jackfruit seed was prepared by dry milling. It is high in protein and carbohydrate contents. The flour has good water and oil absorption abilities (Tulyathan, 2002). The range of possible applications for starch plastics is restricted by their sensitivity tomoisture and water contact and high water vapour permeability.
The biodegradability of starch plastics largely depends on the biodegradability of the copolymer. High copolymer content can adversely affect biodegradability due to the complex interaction of starch and polyester at the molecular level (DegliInnocenti&Bastioli, 2002). Starch is unique among carbohydrates because it occurs naturally as discrete granules. This is because the short branched amylopectin chains are able to form helical structures whichcrystallize. Starch granules exhibit hydrophilic properties and strong inter-molecular association via hydrogen bonding due to the hydroxyl groups on the granule surface (Daniel et al., 2000).
Jackfruit Artocarpus heterophyllus Lam. is a popular fruit-crop that is widely grown in the Philippines and other tropical areas. The ripe fruit contains well-flavored yellow sweet bulbs which are consumed fresh or processed into canned products and seeds embedded in the bulb. Seeds make up around 10-15% of the total fruit weight and have high carbohydrate and protein content and are normally discarded or steamed and eaten as a snack or used in some local dishes. As fresh seeds cannot be kept for a long time, using them as source of starch is advisable (Bobbio et al 1978). Based on the above review of related literature, there is a need to conduct a study on starch-based biodegradable plastic from jackfruit Artocarpus heterophyllus Lam. seeds and because in all studies, nothing has been mentioned about jackfruit seeds as component of biodegradable plastics.
MATERIALS AND METHODS
The flow of processes on starch-based biodegradable plastic from jackfruit Artocarpus heterophyllus Lam. seeds is shown in Figure 1.
Collection and Preparation of Research Materials, Tools and Equipment
The researchers will collect three (3) kilograms of jackfruit seeds from the source for two (2) days before the conduct of the study. These will be brought to the Physics/Chemistry Laboratory of Antique National School, San Jose de Buenavista, Antique.
Technically grade ethanol, hydrochloric acid, acetic acid and sodium hydroxide, ammonia, distilled water, chlorine, polyvinyl alcohol, epoxydized soy bean oil, and glycerol will be obtained from chemworks, Inc.Jaro, Iloilo City prior to the conduct of the study.
The other materials and equipment needed will be mortar and pestle, grinder, beakers, alcohol lamp, rolling pin, aluminum foil, stirring rod, molders, spring balance, double beam balance, tray, plastic cups, graduated cylinder, stopwatch, and hot plate.
Research Procedure/ Experimental Design
Three (3) kilograms of jackfruit seeds will be rinsed and washed in running water and will be air-dried for twenty-four (24) hours at room temperature. After air-drying, the seeds will be peeled manually. Then the seeds will be cut into smaller pieces and ground using an electric grinder. The ground jackfruit seeds will be added with water following the ratio 1:2, one (1) liter of distilled water to two (2) kilograms of ground jackfruit seeds. The mixtures will be placed inside the beaker for decantation for three (3) hours.
After decantation, the supernatant will be discarded and the settling material will be collected and placed in an evaporating dish for the starch sediments to settle. This will be sun-dried for five (5) hours to let the water evaporate completely. After the evaporation process, the collected starch sediments will be ground using mortar and pestle until it will turn into powdered form. The produced starch will be weighed and placed in a sterilized container ready for experimentation.
Measured amount of the water and jackfruit starch based on different treatments will be mixed and boiled using a hot plate at eighty (80(C) degrees Celsius until it will form into a sticky paste. After removing the starch-water mixture from the hot plate, the rest of the materials will be added such as polyvinyl alcohol, epoxydized soya bean oil, and glycerol. After mixing all the materials, the mixture will be heated again using a hot plate at a temperature of one hundred eighteen to one hundred twenty (118-120(C) degrees Celsius for seven (7) minutes. Then it will pass through a rolling pin and transferred to containers for sun-drying process until the plastic will be formed. The plastic will be cut into strips (3 cm wide by 5 cm long) for mechanical property, effects of acid and base, and organic solvents tests, respectively.
The experiment will use five (5) treatments with three (3) replicates each.
The duration of the experimental activities will be seventy-eight (78) days that will begin on July 15, 2011 and will end on September 30, 2011.
The five (5) treatments that will be used in the study are as follows. Treatment A = 100 grams starch + 100 grams water + 100 grams polyvinyl alcohol + 2.5 grams epoxydized soya bean oil +10 grams glycerin Treatment B = 75 grams starch + 100 grams water + 100 grams polyvinyl alcohol + 2.5 grams epoxydized soya bean oil +10 grams glycerin Treatment C = 50 grams starch + 100 grams water + 100 grams polyvinyl alcohol + 2.5 grams epoxydized soya bean oil +10 grams glycerin Treatment D = 25 grams starch + 100 grams water + 100 grams polyvinyl alcohol + 2.5 grams epoxydized soya bean oil +10 grams glycerin Treatment E – Control – Commercial plastic (polyethylene)
Gathering of Data
The cut samples of the produced biodegradable plastic will be subjected to the following tests:
Flammability Test. The strips of the produced biodegradable plastic and commercial plastic with the same dimensions will be completely burned using alcohol lamp and the burning time will be noted.
Soil Biodegradability Test. The plastic strips will be stapled to a piece of cardboard and will be buried in a can of soil. The strips will be unearthed after a week and the final dimension will be recorded.
Tensile Strength Test. The plastic strips will be hooked to a spring balance and will be pulled until they will tear apart. The reading of the balance when the plastic strips will break will be recorded.
Effects of Strong and Weak Acids and Strong and Weak Bases.The plastic strips will be immersed in concentrated strong/weak acids and strong/weak bases for thirty (30) minutes. Changes in length, width, and appearance will be noted.
Organic Solvent Tests. The plastic strips will be immersed in a bottle of chlorinated water/ethanol. The bottle will be sealed so as to isolate its contents from the external environment. After a week, their final dimensions will be noted.