Corn and rice starch based bio plastics as alternative packaging materials

Scientific Research An Academic Publisher. Affiliation s. The oil that is used as a raw material, as well as the oil required for energy, consumes between six to eight percent of the total world oil production.

Although this is a small percentage, the amount of petroleum used to make plastic does contribute to the depletion of fossil fuels. The rate of consumption influences the overall price of petroleum, contributing to the current rise in raw material costs. Plastics derived from petroleum are made from synthetic polymers [2]. Their utility includes but is definitely not limited to agriculture, aerospace, automobile, construction, sports, domestic, and households.

Increase in population and industrial growth have resulted in the increased production of synthetic polymers and allied materials [3]. Polyethylene more often used as carry bag and more is produced annually [4].

corn and rice starch based bio plastics as alternative packaging materials

Non recyclable and synthetic polymeric materials are causing a serious concern in environmental related issues. In particular, the plastic bags which are discarded into the environment have become a menace [5]. Significant quantities of plastic have gathered in the natural environment and in landfills.

Wasted plastic also contaminates a wide range of natural terrestrial, freshwater and marine habitats. There are accounts of inadvertent contamination of soils with small polymer fragments as a consequence of spreading sewage sludge [6]of fragments of plastic and glass contaminating compost prepared from municipal solid waste [7] and of plastic being carried into streams, rivers and ultimately the sea with rain water and flood events [8].

Most polymers are buoyant in water, and since items of plastic debris such as cartons and bottles often trap air, substantial quantities of plastic debris accumulate on the sea surface and may also be washed ashore.

Phthalates based plasticizers and BPA can bio-accumulate in organisms, but there is much variability between species and individuals according to the type of plasticizer and experimental purpose. However, concentration factors are generally higher for invertebrates than vertebrates, and can be especially high in some species of molluscs and crustaceans. Plastics contain phthalates, BPA, flame retardants, cadmium, lead and organo tins, all of which have been shown in animal studies to result in obesity [10].

In addition, the monomer used to manufacture PVC plastic, vinyl chloride, is a known carcinogen and exposure can cause angiosarcoma of the liver among factory workers [11] [12]. In recent decades, the plastic industry and the academic community have been together looking for new raw materials to replace the petrochemical polymers, which are produced from nonrenewable resources [13].

Biodegradable plastic made from renewable resources is decreases dependence on petroleum and reduces the amount of waste material, while still yielding a product that provides similar benefits of traditional plastics [14]. The major difference between synthetic polymers and natural polymers is that the presence of oxygen and nitrogen in the natural polymers.

The oxygen and nitrogen in the polymer structure permit the polymer to biodegrade [15].

corn and rice starch based bio plastics as alternative packaging materials

Bio-based polymers have been shown to be a viable alternative to replace these fossil sources while also having environmental advantages, such as decreasing toxic emissions [16]. Most traditional plastics are inert to microbial attack, and the development of biodegradable packaging, these derived from renewable natural resources, has gained increasing interest [17]. Target markets for biodegradable polymers include packaging materials like trash bags, loose-fill foam, food containers, film wrapping, laminated paper, hygiene products like diaper back sheets and cotton swabs, consumer goods like fast-food tableware and containers, egg cartons, and toys, and agricultural tools like mulch films and planters etc.A company that needs to package their products have choices in which material they use for packaging.

Traditionally companies could use polystyrene materials, which are commonly injection molded or extruded for packaging. However, companies are becoming aware of the environmental impact of polystyrene, such as the inability of the material to biodegrade.

Therefore companies are looking to use recyclable and biodegradable packaging materials where possible. With starch-based packaging materials, the product is biodegradable but is not an inferior material when compared with synthetic polymer materials. Instead of using packaging materials made from synthetic polymers, new material has been developed using polylactic acid PLAwhich is made from fermented sugars, usually from cornstarch.

The materials made from PLA are biodegradable which is important for the environment. If disposed of correctly, packaging material made from cornstarch will break down into carbon dioxide and water within several months. However, if the material is not disposed of correctly cornstarch-based material will take longer to decompose, especially if there is no oxygen or light available.

Corn is the least expensive and most abundant source of commercially available sugar. Synthetic polymer materials are produced from petroleum, a non-sustainable item that can be expensive depending on the price of oil. Corn starched packaging does have some interesting advantages over synthetic materials such as reduced static electricity. Materials made from PLA have advantages and disadvantages over synthetic polymer materials.

Pros and Cons of PLA: Corn-Based Plastic

Some properties of PLA are shown below:. The PLA material can be made into a fiber or a film. There are a number of PLA grades that are available for commercial customers which can be used for a number of different applications.

As PLA materials need to composted rather than recycled, like paper and cardboard, companies need to separate the PLA materials and the regular recyclable materials. Currently, there are only just over a hundred composting facilities in the US. Although PLA materials are able to be composted, the correct conditions must exist. If the material is deposited in a landfill without the proper oxygen and light, the PLA material may not decompose for decades.

PLA materials can be used for many applications but this does not compare to the uses of the more common plastic polyethylene terephthalate PETwhich is used to make bottles consumers use every day. The packaging is important to protecting materials and companies will use the best material for the job.Bio-plastics are a great alternative to traditional plastics, which are often composed of petroleum products.

As years pass, we have less and less petroleum available to us, so it is important to find a suitable alternative. You can't beat the light-weight, low-cost applications of plastic products, so many companies are experimenting with making a similar product out of a more renewable product. Starch plastics are a good alternative, because corn is readily available, and when the plastic is done being used, it can be broken down rather than sent to a landfill.

This is a simple recipe that can be made in any kitchen, with common items often found in the average pantry. It can be a fun experiment for the classroom, as well as at home.

The main purpose of this is to garner interest in the subject, so that future scientists will be able to develop more sustainable ways to make plastic products. Did you use this instructable in your classroom?

Add a Teacher Note to share how you incorporated it into your lesson.

These are all ingredients that can be found in most kitchens, aside from the glycerin. Glycerin is used as a plasticizer in this application, but is often an important additive in lotions and other skin care products because of it's hydrating properties. Different ingredients will affect the final outcome in different ways. For instance, glycerin will make the plastic more flexible. The acetic acid in vinegar helps the starch to dissolve easily, because it adds ions to the mixture.

Vinegar is a much more readily available ingredient than ammonium acetate, which would be used in a larger scale commercial bio-plastics operation. Water is used as a solvent, also to denature the starch. That way, a thin film can be created as a final product. The order does not matter. Simply measure all ingredients this is not rocket science, so it doesn't need to be exact and mix them together in the pot.

After the heat is turned on, the mixture should be stirred regularly to avoid clumping. It will be a milky color at first, but will soon get thicker and turn slightly translucent.

It is important to keep the heat low so that the heat is equally distributed throughout. Once the mixture is easily scoopable, turn off the heat! The foil is optional, but it will be easier to remove later when the plastic is dry. The mixture will feel similar to hair gel when it is first on the pan, and will need to cool a bit before it can be formed.

Let it sit for a minute or so, then spread with a spatula on the foil. Over the next 15 minutes, the plastic will begin to harden and not stick to fingers when touched, but it will still be soft. The plastic should be left alone for several hours, until completely set. If you wish to form the plastic into a small bowl or other simple shape, it can be left on the foil for about an hour, then formed almost like playdoh. After forming, set it back on the foil and allow to dry for several hours or overnight.

Resist the urge to touch the finished product throughout the drying process, as it will still be soft. The great thing about this particular project is that it will dissolve in hot water and is made from materials that will not harm the environment further. If a small child or pet were to chew on your home made bio-plastic, they would not be harmed in any way aside from it being a possible choking hazard.

This is because all of the ingredients are completely safe for consumption. There are a great deal of positive aspects to these environmentally friendly plastics, and I encourage you to continue researching or trying other plastic recipes. Question 4 weeks ago.The term bioplastics is composed of the two words bio and plastics — two conflicting terms for many people.

Nevertheless, plastics can also be biological. Since the term is not sufficiently legally protected, there are different definitions. For some people, bioplastics are plastics made of renewable resources. For other people, bioplastics are all biodegradable plastics including petroleum-based. Our bioplastics are both biodegradable and made of renewable resources. Most of our plastic products consist of the bioplastic polylactic acid PLA which is based on corn starch.

Bioplastics are an environmentally friendly alternative to petroleum-based plastics such as PP polypropylene and PS polystyrene and possess comparable characteristics. They are transparent and can be processed easily into various commodities, for example into cups, bowls, and bottles.

These commodities belong to the most important sales market for bioplastics: the packaging industry, in particular the one for food. Here, bioplastics have a great advantage over conventional plastics because they can be disposed with food left-overs. This means that only a very small amount of petroleum-based plastics is substituted by biological plastics so far. It is expected that the amount of bioplastics will continue to increase within the next years and replace old plastics.

Maize zea maysbetter known as corn, is an annual summer plant and belongs to the family of sweet grasses. It originally comes from Mexico but by now, it blooms from July to September in many parts of the world.

In Germany, the farmers also plant corn during the summer months. The corn plants are 1 to 3 meters in height and bear piston-like fruit bunches with corn grains, which appear in different colours, depending on the species. Just like every plant, maize performs photosynthesis.

Potato-based edible bags and cutlery created to replace plastic

By the aid of the sunlight, it converts absorbed CO 2 and water into glucose and oxygen. The non-required sugar is stored in the form of starch. This corn starch is relevant for is because it forms the raw material for the production of bioplastics. Between September and October, the farmers harvest the corn cobs with field choppers. It is important to note that this corn is solely cultivated for industrial use and is not suitable for human consumption.Bioplastics are plastic materials produced from renewable biomass sources, such as vegetable fats and oilscorn starchstrawwoodchipssawdustrecycled food wasteetc.

Common plastics, such as fossil-fuel plastics also called petrobased polymers are derived from petroleum or natural gas. Not all bioplastics are biodegradable nor biodegrade more readily than commodity fossil-fuel derived plastics. As ofbioplastics represented approximately 0. Bioplastics are used for disposable items, such as packagingcrockery, cutlery, pots, bowls, and straws.

In principle they could replace many applications for petroleum-derived plastics, however cost and performance remain problematic. As a matter of fact, their usage is financially favourable only if supported by specific regulations limiting the usage of conventional plastics [ citation needed ]. Typical is the example of Italy, where biodegradable plastic bags and shoppers are compulsory since with the introduction of a specific law.

Biopolymers are available as coatings for paper rather than the more common petrochemical coatings. Thermoplastic starch currently represents the most widely used bioplastic, constituting about 50 percent of the bioplastics market [ citation needed ].

Simple starch bioplastic can be made at home. Flexibiliser and plasticiser such as sorbitol and glycerine can also be added so the starch can also be processed thermo-plastically. The characteristics of the resulting bioplastic also called "thermo-plastical starch" can be tailored to specific needs by adjusting the amounts of these additives.

These blends are used for industrial applications and are also compostable. These blends are not biodegradable, but have a lower carbon footprint than petroleum-based plastics used for the same applications. Due to the origin of its raw material, starch is cheap, abundant, and renewable.

Starch based plastics are complex blends of starch with compostable plastics such as Polylactic acid, Polybutylene Adipate Terephthalate, Polybutylene Succinate, Polycaprolactone, and Polyhydroxyalkanoates. These complex blends improve water resistance as well as processing and mechanical properties.

Starch-based films mostly used for packaging purposes are made mainly from starch blended with thermoplastic polyesters to form biodegradable and compostable products. These films are seen specifically in consumer goods packaging of magazine wrappings and bubble films. In food packaging, these films are seen as bakery or fruit and vegetable bags.Polylactic acid PLAa plastic substitute made from fermented plant starch usually corn is quickly becoming a popular alternative to traditional petroleum-based plastics.

PLA also will not emit toxic fumes when incinerated. However, there are still issues with the use of polylactic acid such as its slow rate of biodegradability, its inability to mix with other plastics in recycling, and its high use of genetically modified corn though arguably the latter could be one of the good effects of PLA as it provides a good reason to alter crop yields with genetic splicing.

For one thing, although PLA does biodegrade, it does so very slowly. It will take far longer in a compost bin, or in a landfill packed so tightly that no light and little oxygen are available to assist in the process. Indeed, analysts estimate that a PLA bottle could take anywhere from to 1, years to decompose in a landfill.

Another issue with PLA is that it must be kept separate when recycled, lest it contaminates the recycling stream; since PLA is plant-based, it needs to be disposed of in composting facilities, which points to another problem: There are currently a few hundred industrial-grade composting facilities across the United States. This is tricky because the future costs of genetic modification and the associated pesticides to the environment and human health are still largely unknown.

Genetically modified foods may be a controversial issue, but when it comes to genetically spicing plants together to breed corn that yields more crops for industrial use has its major advantages. At least harmful plastic isn't be used as frequently anymore! Many industries are using PLA because they are capable of biodegrading at a much faster rate than plastic while still offering the same level of sanitation and utility. Everything from plastic clamshells for food take-out to medical products can now be made from PLA, which drastically reduces the carbon footprint of these industries.

While PLA has promise as an alternative to conventional plastic once the means of disposal are worked out, consumers might be better served by simply switching to reusable containers, from cloth bags, baskets, and backpacks for grocery shopping to safe, reusable non-plastic bottles for beverages.

Share Flipboard Email. By Larry West. Updated August 07, Bioplastics help manufacturing companies stay competitive by helping to meet rising consumer expectations of sustainability. They are often derived from various biomass sources, the most widely used being starch, which is a natural polymer that can be incorporated in various materials.

corn and rice starch based bio plastics as alternative packaging materials

Starch-based plastics can be used in a variety of applications since they can be incorporated with various petroleum-based polymers or biopolymers to create unique composite materials.

These composite materials can then be injection molded or extruded using standard processing machinery. In general, starch-based plastics are more cost competitive than alternative bioplastics.

They can accommodate a wide range of physical properties that alternative bioplastics lack, such as tensile strength and heat tolerance. Starch composites can also incorporate recycled plastics.


Our team recommends starch-based plastics when recycled plastics need to be used or if clients require a material that exhibits properties alternative biobased materials cannot display. Starch can be used to reduce the carbon footprint of traditional resins because they can replace petroleum-based polymers with natural ones.

It is also highly degradable, meaning it can be used alongside a compostable polymer without interfering with the degradation process.

Out of the 2. These diverse applications mean that identifying the correct combination of materials is critical. Their physical properties differ from unfilled plastics because they can be processed similarly to mineral-filled plastics. However, proper formulation can overcome most issues. Future opportunities will come from a continued capacity for growth and consumer demand for environmentally-friendly products as well as efforts to reduce pollution and reliance on petroleum-based products.

The Green Dot Bioplastics team has successfully developed cell phone cases from compostable, starch-based plastics. Additional opportunities are expected in compostable yard and kitchen bags, food service disposables and various types of packaging. Starch-based plastics have increased in relevance with the introduction of improved resin grades, their ability to blend with other biopolymers and an increasing number of suppliers. In fact, starch-based bioplastics are widely employed in the medical industry because of their biocompatibility, low toxicity, degradation properties and mechanical properties.

Our team has wide range of available formulas for clients, created to increase the bio-content of products made with petroleum-based plastics and to quicken the biodegradation process of biodegradable plastics. Like most biopolymers, starch-based materials can be bio-based durable materials, such as our Terratek SC line, or they can be used in any number of compostable formulas. Either way, they can be used for injection molding grades, extrusion grades or film grades. The bioplastics handbook for injection molders Get a straightforward discussion of processing best practices for bioplastics.

The Green Dot Bioplastics team works closely with clients to develop customized materials capable of performing specialized functions. In fact, the Terratek SC line can be customized to accommodate a wide variety of physical properties e. Its applications include diverse products such as tableware and golf tees. For instance, parts with thin wall sections may require higher melt flows. Future research in starch-based plastics will likely be aimed towards biodegradable applications.

We will also see a wide range of renewable, reclaimed and compostable materials replace traditional, petroleum-based plastics a movement that is already underway.

corn and rice starch based bio plastics as alternative packaging materials

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