Can any one describe the exact process to make bio-degradable plastic from the corn seeds...???

Question

I read many articles on net but didnt got exact components and process to follow.. Try to make it specific and detailed please..

Answer 1

I am also a Agriculture officer in PunjabGovt. and studied from PUnjab Agricultural University Ludhiana, Asia's No.1 agriculture University... i am also working on CORN NOW....... So Small link for.......

http://www.ksgrains.com/corn/CornClass04...

and you can also mail me for more information i.e [e-mail]

Abstract;Refined powers of of proteins derived from seeds of corn, rice, wheat and soybean were prepared and the powders were pressed under high temperature and pressure to obtain transparent films. It was confirmed that the films underwent biological degradation in soil. Zein protein was extracted from maize seed. Film made by pressing a mixture of the zein protein and paper was three times as strong as one made from the zein protein alone. It was possible to form the mixture into a form of container by applying high temperature and pressure in an aluminum mold. Polyurethane film was made from zein protein, PEG (polyethylene glycol) and MDI (diphenylmethane diisocyanate). In addition, a molded product was made from a mixture of zein protein and appatite.

click on the link

www.agintheclassroom.org/060605/Teache... -

Choosing A Biodegradable Plastic  

     When choosing the biodegradable plastic that you are going to use, you have to ask several questions in order to get the correct plastic:  how are you going to use the plastic, how is the plastic going to be stored and for how long? Finally, one has to consider where this plastic product is going to be discarded.The following is a comparison of the positives and negatives of biodegradable plastics.

“Green Film”

Positives:

Will biodegrade in landfills and natural bodies of water.

Will compost.

Can be safely recycled with regular plastics.

Have no heat issues.

Has no expiration dates.

Leaves no harmful chemicals or metals behind after degrading.

Will not degrade when exposed to moisture.

Will not break into pieces like oxy degradables.

Negatives:

Does not compost in 180 days. (It takes 270 days.)

Uses petroleum by-products in its manufacture. Note: plastic bags use .03% of all the oil use in the US in one year. (Ecogeek, January 31, 2008)

Biobased corn products

Positives:

      1. Will degrade in commercial or municipal aerobic composting facilities in 6 months

        (As per ASTM 6400). Please note: will NOT degrade in landfills.

Negatives:

Not sustainable- uses more fossil fuels than polyethylene as per “How Green are Green Plastics” in Scientific American”, Aug. 2000. The author states this belief on the cradle to cradle development of the product. Please consider the treatment of the soil before planting with a chemical, “Roundup”, which reportedly reduces the fertility of the soil; then the machine that plants the seed corn; then fertilization of chemicals; then the watering of the corn; then the harvest by machines; then the process where the corn is made into a finished product. NatureWorks’ website has an article that shows that their sustainability claims are based on buying renewable energy certificates. (“Sam's Club Partners with NatureWorks PLA to help the environment”, October 21, 2005.) Also this lack of sustainability is noted in Popular Science, Sept. 2007, where they state that one should not take “eco claims at face value. Companies may tout the value of natural fibers without mentioning some of the unnatural methods used to produce them. Take corn and bamboo for example. Both have the potential to be green, but environmental concerns remain.” “Concerns: Energy from fossil fuels goes into producing pesticides, herbicides and fertilizer for corn.”

PLA will not degrade in landfills where most trash ends up. Normal plastics take 400 years to degrade in landfills. PLA which requires oxygen, moisture, and heat to degrade will probably last that long also. Landfills in the eastern US are nearly full and, according to the EPA, many have a life expectancy of 15 years.

Can break down in temperatures over 110 degrees such as in trucks or warehouses. Thus they require storage in temperature controlled warehouses and being shipped in temperature controlled trucks using more energy.

Have expiration dates of about 6 months.

Cannot be recycled with normal recyclable plastics. This has greatly affected plastic recyclers in the US according to articles in Plastic News.            

There are only approximately 113 commercial or municipal compost facilities in the US. Only 1/4 or 28 take food scraps so the chances of PLA being properly disposed of are slim. Backyard composts cannot degrade PLA as they are not hot enough according to Smithsonian Magazine, Aug, 2006.

Because of the extensive growing of corn for PLA and ethanol, food costs have increased 10 to 13% according to the Dept. of Labor, for the year ending in June, 2007. The price of meat, chicken, pork, cheeses, flour, vitamins, and milk have leaped. A gallon of milk is at $4.00 a gallon where gasoline has dropped to $3.00 a gallon. Perdue and Smithfield Farms have both stated that the increase in cost of cattle feed has caused them to increase prices. Lance Foods announced on February 21, 2007 in an article in The Charlotte Observer, that there is less wheat being grown as farmers have switched to growing corn, thus increasing flour costs 30-40% in the last quarter alone.

The extensive growing of corn and the heavy fertilizing it requires has polluted aquifers in the Midwest according to the Salt Lake Tribune. The aquifers were also being depleted with the heavy watering needed for corn.

The nitrogen used in fertilizers for corn is also polluting rivers and the Gulf of Mexico. Corn requires heavy use of nitrogen in its fertilizing which has run off the fields into rivers and down the Mississippi into the Gulf of Mexico. This nitrogen feeds microscopic organisms that deplete oxygen levels as they die. The Gulf now has a dead zone 8,543 square miles according to Nancy Rabalais of the Louisiana University’s Marine Consortium. This area equals the size of New Jersey. And, unfortunately, this area is expanding. The dead zone has resulted in a 40% reduction in the number of licensed fishermen and shrimpers since 2001. The Chesapeake Bay has also been affected. (Taken from Bloomberg News, July, 2007.)

According to life-cycle reports done by Franklin Associates in December, 2007, a HDPE container consumes less energy, produces less post-consumer solid waste, and generates fewer greenhouse gas emissions than containers made from corn-based PLA. (Please note: Franklin Associates have prepared many reports in the past for the EPA.)

PLA/ethanol is creating more global warming pollution than gasoline according to the  Environmental Defense Org., November, 2007.

Oxy Degradable Products

Positives:

Will degrade in commercial or municipal composting facilities.

Will degrade when exposed to sunlight.

Negatives:

Will not biodegrade in landfills.

While degrading, it separates into small pieces that can blow away before degrading completely thus polluting neighboring area.

Will degrade when exposed to high temperatures in warehouses or on trucks.

Come with expiration dates of approximately 6 months.

Some oxy degradables leave dangerous chemicals and heavy metals such as cobalt and cadmium in the soil after degrading.

Germany’s IK Plastic Packaging Association states that oxy degradables do not meet biodegradability/degradability standards and will not longer be considered as such. (March 2006) As Germany is a leader in biodegradability, one cannot ignore such findings.

Cannot be recycled safely with other plastics.

According to the Sydney Morning Herald, January 17, 2008, tests done on EPI oxy-degradable bags showed that they do not degrade any faster than normal plastic bags. It revealed heavy metals are the catalyst in making them degrade which are left behind. Environmentalists say this makes them potentially worse than regular plastic bags.