The recent study indicates that industrial sectors and researchers have had augmented interests in production of plastics that are biobased. There are several reasons that are attributed to this observation, some of which include the increase in the price of oil which eventually increases the prices of raw materials that are manufactured from petrochemicals (Tanrattanakul & Saithai, 2009). This research paper seeks to look into the production of bio plastics in the world today. The paper will therefore explain the concepts and technologies used to produce bio plastics. The research works will also look into their pro and cons, and how they have been integrated in the world consumption today. A critical analysis of bio plastics and how they are related to the environment will also be investigated.
What are bioplastics? Plastics resins which are biodegradable or derivative of plant raw materials are referred to as bioplastics (Shen, Worrell & Patel, 2009). There has been an increasing interest in application of bioplastics in the world today. This is attributed to the increasing prices in oil prices and the decreased supply for raw materials used to manufacture petrochemicals. Bioplastics are similar to traditional plastics in their application but the difference is that they are characteristic biodegradable in a specified composting cycle. Environmentalists have also been in the look out for clean and sustainable environment and therefore a demand for products that are environmentally friendly. The impacts of global warming on the environment due to the continued production of conventional plastics have been an issue on the rise. This is especially in regard to the amounts of energy consumed and the effects of greenhouse in some specified areas (IBAW, 2005).
Studies have however shown that while most bioplastics are biodegradable, some which are categorized as durables are non-biodegradable. These are fundamentally based on fossil resources including and not limited to poly-ethylene. Bioplastics materials are said to be biodegradable because of the fact that they can undergo degradation process when micro-organisms act on them eventually giving water, carbon dioxide gas, organic compounds such as methane and biomass. Biodegradation process is said to be a cell-initiated process that uses micro-organisms, enzymes, bacteria and fungi. On the other hand, compostable plastics can undergo degradation process due some specific biological processes. The biological processes takes place during the composting process and the material is eventually converted to carbon dioxide gas, water vapor and organic compounds such as biomass (Carus & Piotrowski, 2009).
Most agricultural products are renewable and as a result, materials made of plastic from renewable products such as Soyabean oil (SO) are on the increase. New bioplastics have been developed from Soyabean Oil. Researchers have also found that Soyabean oil maybe modified to suit different applications which include and not limited to sheet molding compounds made of plastics, coating materials, adhesive products among others (Schut, 2008).
Renewable resources are the identified sources for bioplastics. Such resources include corn, and potatoes. Bioplastics are also derived from starch. These bioplastics products are used in industries where degradability factor is a sufficient requirement. Such industrial application includes the production of composting bags and sacks, plates among other applications. The enhanced technological performances exhibited by bioplastics application when compared to traditional materials have resulted in the growth of new sectors dealing with biodegradable materials. Bioplastics are currently being used in the various applications where the aspect of biodegradability is of great concern (Stevens, 2006).
When bioplastics are compared to traditional materials, they offer a range of differences in terms of recycling processes, economy and impact on the environment. The recycling process for bioplastics is not complicated, economical and takes place in real time. The fact that they are biodegradable explains why they have less impact on environment and have thus been used for widely in various sectors. Composting technologies have been employed for various disposal applications; this technology is quite economical when employed in biodegradable disposal of bioplastics (Oku, 2005).
Importance of using bioplastics
Bioplastics helps to offer a solution to the disposable problems in plastic application. This is because; they are biodegradable, meaning that they can be recycled and thus reused again. Most industries prefer the use of bioplastics raw materials compared to traditional raw materials. This is because of the advantages accrued with the use of these materials. An industry that produces bioplastics have a wide range of raw materials, that's of high quality at a cheaper price and thus creating a competitive advantage (EUPC, 2007).
Bioplastics production also allows the incorporation of new technologies in the manufacturing and processing techniques. They also help to create new fields of business due to the niche products manufactured from bioplastics. Their biodegradability characteristic is practical and thus environmental friendly. Bioplastics products help to enhance sales through packaging of such food products as organic materials on packages that are compostable (EUPC, 2007). As indicated in the diagram below, the importance bioplastics production and consumption process leads to interrelated benefits to the society (EUPC, 2007).
Importance of bioplastics to agriculture
Bioplastics help to create new potentials needed in the agriculture industry. Renewable resources from agricultural feedstock are of great use in the production of bioplastics. Most of bioplastics products are of great use in the agriculture (EUPC, 2007).
Helps in waste management
Their biodegradable characteristic facilitates decomposition process and hence reduces on the quantity of wastes from the society today. This characteristic helps to make the management of waste less time consuming and economical. They have thus been incorporated in the production of packaging materials used in supermarkets among other sectors in the food industry. Inncenti et al., (2007) argues that the introduction of bioplastics materials in some industries such as catering companies helps to augment the composting rates and quantity of wastes collected for disposal. The use of bioplastics products in industries helps to reduce exposure of harmful elements such as trace metals (Leadbitter, 2002).
Bioplastics facilitates carbon neutrality
Global warming effects on the environment have increasingly facilitated the greater use of bioplastics. This is because; studies have shown that continued increase in the amount of carbon dioxide in the atmosphere leads to global warming. The use of bioplastics helps to reduce on the amount of carbon dioxide emissions to the atmosphere. Studies conducted by Matsuura, Ye and He (2008), show that carbon dioxide that's produced in the bioplastics products production process originates from biomass. The life cycle of such a gas is considered to be neutral (Matsuura, Ye & He, 2008).
Economical in their production and use
Due to the increased concern on the fuel shortages, products that consume less fuel in their production and use have increasingly become of great importance in the industrial sector. When compared to ordinary plastics, the production process of bioplastics uses minimal fossil fuel; meaning that they are less dependent on petroleum fuel (Leadbitter, 2002).
Types of bioplastics
According to Matsuura, Ye and He (2008), two classifications of bioplastics have been identified; these include:
§ These are plastics that fall under renewable biomass of carbon compounds. These include, and not limited to such compounds as oil from soy bean, starch from potato and corn products. They may also be derived from microbes' process that leads to the formation of cellulose (Matsuura, Ye & He, 2008).
§ Biodegradable plastics that are produced from biomass or compounds of fossil fuels. The bioplastics that falls under this category undergo a production process in three major categories (Matsuura, Ye & He, 2008).
Plastics that can undergo decomposition process to give gases such as carbon dioxide and methane vapor, among other organic and inorganic compounds falls under this category. The decomposition process is facilitated by microbial action on the elements that make up the complex compound. Plastics made from Polylacticacid (PLA) have undergone commercialization process and have eventually been of use in various sectors (Matsuura, Ye & He, 2008).
Matsuura, Ye and He (2008) continues to argue that some biodegradable plastics are made of other materials apart from biomass. Such sources include fossil fuel polymers and have given rise to biodegradable and compostable plastics such as polybutylenexacinate and polyglycolic acid. The table below gives a high light of bioplastics compared to biodegradable plastics.
The above table shows the different types of bioplastics categorized by the production process.
Source: Matsuura, Ye and He (2008).
Materials used to make bioplastics
The current market employs renewable sources to produce bioplastics. Renewable resources enable the production of bioplastics that are biodegradable. Starch has been used widely in industry to produce bioplastics. It is not as expensive as other resources and it's readily available from plant products such as corn, among others. It has complete biodegradability characteristics in various environments and can therefore be used to produce bioplastics products that are degradable and that suits different tastes and preferences (Bastioli, 2001).
The crystalline nature of starch allows it to be destroyed by heat; this means that it can be destructurized and thus can undergo modification to help it attain properties used to make various bioplastics products. This facilitates the production of materials that are of high heat resistant properties, and hence used in industrial processing and compression processes (Bastioli, 2001). When starch have undergone destructurization process, they attain thermoplastic properties and are treated, if need be, as traditional plastics (Sarnacke, & Wildes, 2008).
Destructurized starch when applied in industry helps to replace industrial application of polystyrene. When destructurized starch is applied alone, they help to produce soluble compostable foams. Due to the various market needs in the current society, after starch has been destructurized, it is then compatibilized. The materials used for these two processes are synthetic polymers. This leads to the production of high quality bioplastics, with high resistant and tensile properties; thermoplastic starch is an example of such products (Bastioli, 2001). To further enhance their properties, destructurized starch undergoes complexing process with such complex compounds such as thermoplastic polyesters. Such products are highly biodegradable and compostable and can thus be used in various applications (Theinsathid, Chandrachai & Keeratipibul, 2009).
Bioplastics materials made from starch products have the highest market share in the current industrial application. This is because of the fact that they completely derive bioplastics products that are biodegradable originally from renewable resources. They are mostly used in the industry today to make composting bags and loose-fillers (Bastioli, 2001).
Polylactic acid materials
Lactic acid can be classified as a raw material that's renewable in nature, derived from fermentation process. Lactic acid may undergo classical polymerization to produce polylactic acid. Polylactic acids have a characteristic high melting point of about 170 oC and a 55 oC glass transition temperatures. The L-lactide and D-lactide which are mirror images of polylactic acids can undergo copolymerization process. This process helps to control crystalline of polylactic acids, their crystallization and transparency rates (Bastioli, 2001). They are thus used in the food packaging sector and fiber production, among other sectors.
It's however important to note that certain controlled conditions are required for biodegradability properties of polylactic acid to be achieved. Specific standard machines have been designed for this process (Bastioli, 2001).
Technologies used to make bio plastics
Bio plastics are manufactured using by polymers. There are two types of bio polymers that are used in the technology of production of bio plastics; those that are extracted from living organisms and those that need to be polymerized though they come from renewable sources (BioBasics, 2006).
The Biopolymers from living organisms include Carbohydrates, and proteins. In the production process the cellulose required may be extracted from wood, corn wheat and cotton. Soya beans produce soya proteins that are very vital in the production process. Starch is obtained from potatoes, corn, wheat, and tapioca. Polyester is obtained form bacteria and is created through natural chemical reactions carried by some specific bacteria (BioBasics, 2006).
The manufacturing process also requires polymerized molecules that come from natural resources. It is polymerized and used in the manufacturing process. It's produced from bets, potatoes, and corn through a process of fermentation. It's than polymerized to produce polylactic acid which is a polymer necessary for plastic production. One may also require triglycerides that are obtained from vegetable oils. The triglycerides are polymerized into plastic (BioBasics, 2006).
There are two methods that may be used in the production of bio plastics; the use of fermentation and the use of plants in factory for plastic production (BioBasics, 2006).
1. In the Fermentation process microorganisms are used to break down organic substances in oxygen's absence. One can used genetically engineered microorganisms that are specially designed for prevalent conditions in the fermentation process. There exist two ways n which the fermentation can be done in order to create bio plastics.
Bacteria polyester fermentation: among the other microorganisms that can be used in the fermentation process bacteria group takes the lead. Fermentation can be defined as a process used to create polyester. Bacteria use sugars in plants to fuel cellular process. What is produced as by product is the polymer. Ralstonia eutropha bacteria are used to do this. The polymers produced are separated from bacteria cell (BioBasics, 2006).
In lactic acid fermentation: in this process of lactic acid is fermented from sugars in the same process used to manufacture polymers bacteria. In this fermentation process the final product is lactic acid but not polymers. The lactic acid produced is converted to polylactic acid in traditional polymerization process (BioBasics, 2006).
2. Growing plastic in plants: plants can be made to factories of plastic production. Through a research process Arabidopsis thaliana plant has been created using generic engineering. These plants have in the enzymes that are used by bacteria in plastic creation. These bacteria convert sunlight into energy hence making plastic. Through research technologists have managed to transfer the genes that code for the enzyme into these plants. These plants hence produce plastic through plants cellular process. Finally the plants are harvested and the plastic in them extracted through solvent process. Distillation process is then done so as to separate the plastic from the liquid formed. The whole process of bio plastic production revolves around genetic engineering and fermentation process. Fermentation has the roe of realizing cellulose from plants; the released cellulose is used in the formation of plastic. On the other hand genetic engineering is used to create plants that are specifically grown as raw materials for bio plastic production (BioBasics, 2006).
Integration of Bio plastics
Bioplastics have been used extensively today and are produced from mainly from starch. They however are classified into two main categories: (Bastioli, 2001).
§ Starch-based materials
§ Polylactic acid (PLA)
Bioplastics derived from starch usually undergo some modifications. They are either used singly or are taken through complexing process, whereby they are ‘mixed' with biodegradable polymers that are either natural or synthetic. Polylactic acid bioplastics are derived from starch that first undergoes fermentation process. This process yields lactic acid. The lactic acid obtained can therefore undergo polymerization process to obtain polylactic acid used to produce bioplastics (Bastioli, 2001).
There is quite a variety of products that are manufactured from bio plastics. The bioplastics products that are made from starch are widely used to make career bags. Since 1999 when they were introduced in the market their market has grown immensely with many companies producing a verity of such bags. The bags perform like LDPE in terms of maximum load. They are good for variety of weathers (Mercier & Feillet, 1975).
The food packaging industries have fully embraced this technology. Film wraps and food containers are in great use. There are very many firms that make use of the bioplastics to do packing so that even after disposal the containers will not have adverse effects as plastic would have. They are used for packing bread, fruits, and vegetables among other variety of foods. PLA thermoformed pots are used for packing products like Yogurt (Mercier & Feillet, 1975).
Bastioli (2001) argues that bioplasitic materials from renewable sources have a great application in the society today. Packaging applications of bioplastics products have a great use in the industries; these include:
§ Carrier bags
§ Consumer products packaging
§ Packaging of food materials
§ Manufacture of composting bags
§ Industrial packaging of foamed products
§ Food service ware
Pros and Cons of bio plastics
There are immense problems that have been caused by plastic hence any solution to plastic problems should be taken positively and tested for the various advantage it posses. Bioplastics have their own advantages as we as drawbacks.
Bioplastics have been evaluated and found to reduce 30-80% of Green House Gas Emission that one would obtain from normal plastics. They facilitate the reduction of emission of carbon dioxide (CO2). 1 metric ton of bio plastic has been found to generate between 0.8 to 3.2 fewer metric tons of CO2 than a metric ton of plastic from petroleum. Neath (2007) p 1 has noted that “Electronic giant Sony uses PLA in several of its smaller components, including one of its new walkmans, but in future hopes to use PLA-based polymers to reduce its carbon dioxide emissions by 20pc and non-renewable resource input by 55pc compared to oil-based ABS” (Neath, 2007. p 1).
Over the years the prices of oil has been rising. This has been triggering plastic prices. Bio plastics are cheaper to produce hence the need of the world to employ more resources in utilizing these technologies. Bio products at the same time reduces the quantity of toxic run-off that is generated by oil based products (Neath, 2007).
Other advantages that have been related to bioplastics are that they are biodegradable. This means they are environmental friendly reducing environmental pollution. They also have a high processbility. Bioplastics products are derived from renewable resources unlike the oil based plastics. They also have better mechanical processes as compared to oil based plastics.
Disadvantages of bioplastics:
They increase the problem of littering. Many people have a weakness in that once they realize that the bioplastics do not have long term effects on the environment thy loose the discipline of right disposal process and drop the containers and bags without caring. It should be noted that a biodegradable plastic does not disintegrate immediately its disposed it may take more than a years before it's out of vicinity making the environment to be dirty. For example a banana skin will take two to three years before hanging somewhere before it's broken down (Neath, 2007).
Some of the bioplastics are used to make food packaging. Owing to the fact that they are biodegradable the breaking down process may start when the container is already holding the food staff such as milk hence becoming dangerous for human consumption. The decomposition of bio plastics is accompanied by the production of methane gas. Thee gas which is a very powerful green house gas has a vast effect on the global warming. Some of them leave toxic residuals in the breaking down process (Neath, 2007).
The fact that most of the bioplastics are made from plants many agricultural food producers are turning their attention to this production which in effect is leading to food shortage. It's estimated that some years to come the food prices is gong to be very high. Some bioplastics such as PLA are made from genetically crops that many environmentalists have criticized as being very harmful to the environment. Most of bio plastics can not be recycled. This may eventually lead to an increased cost of products and may hamper the current endeavor to recycle plastic products (Neath, 2007).
Examples of bioplastics products include and not limited to fibers, or bonded fabrics, films, panels, polymers, laminates, bio-plastics, hardware, surfactants, fuel additives, amenders of soil, waxes, packaging materials, paints, in production of paper and their products, among other products (Singh et al., 2003).
Bioplastics production and environmental impacts
The continued use of non-biodegradable materials has been attributed to the current harsh climatic conditions. Such environmental issues include global warming, increased global pollutions and decreased natural recourses due to industrialization.
Some bioplastics undergo the process of degradation at a minimal rate and are therefore put in landfills. Since landfills are covered with clay, biodegradation process takes place slowly, which means that decomposition process takes a long time. Although this is the case, bioplastics have been considered to be still environmentally friendly than the traditional plastics (Innocenti et al. 2007). According to Gerrain et al. (2007), the examination of polylactic acid life cycle shows that their environmental impact is less minimal when compared to the petroleum based films impacts on the environment (Matsuura, Ye & He, 2008).
The biodegradability and the carbon neutral nature of some bioplastics help in conservation of oil reserves. They also help in reduction of carbon dioxide wastes emissions. Some bioplastics materials facilitate the improvement of soil through their interaction with living matter. Bioplastics materials used in the manufacture of some car parts are environmental friendly. Bioplastics sustainability analysis facilitates the reduction of wastes to the environment. It also helps to limit the level of toxicity in aquatic and terrestrial environments (Matsuura, Ye & He, 2008).
The consumer end products and packaging have been considered to be environmental friendly. Some Bioplastics products take a long time to decompose and as a result, hence are not environmental friendly. For instance, polylactic acid does not decompose when deposited in landfills. Their decomposition is facilitated by some specific conditions such as temperature and humidity. Additives that facilitate bioplastics degradation therefore need to be designed; lack of commercially available additives has been created by limitation in technology. To overcome the environmental challenges, enhanced environmental standards that allow biological treatment of bioplastics needs to be developed (Matsuura, Ye & He, 2008).
Bioplastics materials find various applications in the industrial sector due the degree of various industrial products that can be derived from these materials. Bioplastics products derived from starch materials finds more application than any other renewable resources. This is because of its various properties suits the current market, economy and environment impacts. They have a biodegradation ratio close to cellulose, with their mechanical characteristics related to traditional plastics. They have thus been classified as best renewable sources suited “for the production of films, injection molded items and foams” (Bastioli, 2001, p. 355).
The study has also found out that food packaging sector does not employ bioplastics materials extensively because of the following reasons. The high prices involved may reduce the market base for such products. Bioplastics may have non ideal water characteristics, meaning that they may allow infinitesimal amounts of water to permeate through. Research works have not been done extensively to indicate the level of food contamination while packaged in these packages. Some food products have chemicals that could react or interact with elements in the packaging containers leading to contamination or formation of toxic products.
It is however important to note that bioplastics products are used in food packaging in such areas as food service ware items. Fundamental research on the extent of interaction between bioplastics products and food products could enhance their application in the food packaging sector.
Bastioli, C. (2007). Global Status of the Production of Biobased Packaging Materials. Starch, 53: 351-355.
BioBasics, (2006), Biopolymers and Bioplastics. Retrieved on 15th January 2010 from: http://www.biobasics.gc.ca/english/View.asp?x=790
Carus, M. & Piotrowski, S. (2009). Land Use for Bioplastics. Bioplastics magazine, 4(1).
European Bioplastics. 2007.Production capacity. Retrieved on 15th January 2010 from: http://www.european-bioplastics.org/index.php?id=141
European Plastic Converters, EUPC. (2007). Bioplastics and biodegradability: Questions and answers. Kortenberghlaan, Belgium, Retrieved on 15, 2010 from: www.plasticsconverters.eu
Garrain, D., Rosario, V., Pilar, M., Vicente, F., & Cebrian-Tarrason, D. (2007). LCA of biodegradable multilayer film from biopolymers. Paper presented at 3rd International Conference on Life Cycle Management.
IBAW. (2005). Highlights in Bioplastics. USA: International Biodegradable Polymers Association & Working Groups.
Innocenti, Francesco, D., Francesco, R., Maurizio, F., & Catia, B. (2007). “Life cycle management in bioplastics production.” Paper presented at 3rd international conference on life cycle management, Zurich.
Leadbitter, J. (2002). “PVC and sustainability.” Polymer Science, 27: 2197-2226.
Matsuura, E., Ye, Y. & He, X. (2008). Sustainability Opportunities and Challenges of Bioplastics. School of Engineering Blekinge Institute of Technology, Karlskrona, Sweden.
Mercier, C. & Feillet, P. (1975). Cereal Chem. New York, NY: Sage Publishers.
Neath, H (2007), The science of how "taters" can become Tupperware. Retrieved on 15th January 2010 from: http://www.thenakedscientists.com/HTML/articles/article/bioplastics/
Oku, A. (2005). “Changing awareness of researchers and engineers towards sustainable society.” Chemistry, 60(12): 46-49.
Sarnacke, P. & Wildes, S. (2008). Disposable Bioplastics: consumer disposables, agricultural films. Journal of united soybean Board, a market opportunity study, 1(2), 1-35.
Schut, H. (2008). “What‘s ahead for green' plastics.” Plastic Technology. Retrieved on January 15, 2010 from: http://www.ptonline.com/articles/200802fa1.html
Shen, L., Worrell, E. & Patel, M. (2009). Present and future development in plastics from biomass. Society of Chemical Industry and John Wiley & Sons, Ltd. Biofuels, Bioprod. Bioref. 4: 25–40.
Singh, S., Ekanem, E., Wakefield, T. & Comer, S. (2003). Emerging importance of bio-based products and bio-energy in the U.S economy: information dissemination and training of students. International food and agribusiness management review, 5(3).
Stevens, E. (2006). “An introduction to the new science of biodegradable plastics.” In Green plastics. New York, NY: Princeton University Press.
Tanrattanakul, V. & Saithai, P. (2009). Mechanical Properties of Bioplastics and Bioplastic–Organoclay Nanocomposites Prepared from Epoxidized Soybean Oil with Different Epoxide Contents. Journal of Applied Polymer Science,114, 3057–3067.
Theinsathid, P., Chandrachai, A. & Keeratipibul, S. (2009). Managing Bioplastics Business Innovation in Start up Phase. Journal of Technology Management and Innovation, 4(1), 82-93.