Friday, May 21, 2010

Plastic Moulding Innovation for The Smaller Company

Everywhere you look in the world you can see and feel plastic. Its pivotal to our lives – it is hard to imagine life without plastic fantastic. No wonder plastic mouldings is a massive global business.

Approximately 30% of all plastic materials are manufactured by injection moulders. A very large proportion of this percentage is made through custom injection moulders technologies. The process of custom injection moulding is quite complicated to the uninitiated and requires a large amount of specialised machinery to make it happen. That is before the consideration of the selection of the raw materials which must be chosen for its quality and elasticy that depends on the end product being developed.

Given the wide-spread utilisation of plastic, there are many smaller companies that could benefit massively from plastic injection moulders as a way to produce parts. Given that the equipment needed is expensive, the overheads for developing new products is preventing companies from innovating.

Thankfully, for these smaller companies, there are organisations that specialise in custom plastic injection moulders. They will make a mock up mould to the exact specifications, run it through the complete process and present the completed product to the customer for analysis.

One such company serving the UK is Iota Sigma. If you are looking at developing cost effective plastic mouldings through the utilisation of injection moulders then Iota Sigma, a Wales based Plastic Mouldings manufacturer, can provide friendly and constructive advice. They can help develop products from the very first sketch through to custom rapid prototyping making a new concept for the enterprising company a low-cost reality.

Iota’s Sigma’s involvement early on in the development of a project can be a distinct advantage to the final finished product. They claim their professional approach in ensuring customer quality, materials, process to meet specific goals and their plastic mouldings knowledge utilising Injection Moulders are second to none. They are fully quality-driven and covered in the scope of their ISO9000 quality accreditation.



Article Source: http://www.articlesbase.com/industrial--articles/plastic-moulding-innovation-for-the-smaller-company-1445870.html



About the Author

Visit http://www.iotasigma.co.uk for complete details.



Thursday, May 20, 2010

Plastic as a Source of Environmental Pollution What is the Solution?

Plastic as a source of environmental pollution what is the solution?
Dr.Kedar Karki
Background:
Plastics are synthetic substances produced by chemical reactions. Almost all plastics are made from petroleum, except a few experimental resins derived from corn and other organic substances.

"Plastics" derived their name from their properties to be molded, cast, extruded or processed into a variety of forms, including solid objects, films and filaments. These properties arise from their molecular structure. Plastics are polymers, very long chain molecules that consist of subunits (monomers) linked together by chemical bonds. The monomers of petrochemical plastics are inorganic materials (such as styrene) and are not biodegradable.

Plastic has many properties which has made it a raw material of choice for Manufactures of plastic Bags and packing materials. Cost of production, light weight, strength, easy process of manufacture, and availability are few of the properties. There is nothing wrong with plastic as a material. Man has simply not put the plastic to the right use/ or using it without taking proper care of other related norms of usage.

PLASTIC AS PACKING MATERIAL:

Plastic has replaced the traditional material (paper/cloth etc) as packing and carry bags because of cost and convenience which is possibly a wrong choice of material for such use. Even though plastic bags can preserve food and can be used for growing vegetables in a controlled environment, their method of disposal has creates unprecedented pollution problem.

Plastic has many more uses other than Plastic Bags and Packing material. It is used for manufacturing of protective covers and parts for many machines, which should be the preferred utility for plastic.

SHOPPING CULTURE IN EARLIER DAYS:
Before the advent of poly-bags, people did shop, buy things, bring eatables from the market, and did the same marketing as is done now. How did they do it? The raw material for the bag was decided by its usage. Cloth bags for lighter items, Gunny bags/Jute bags for voluminous and heavier goods. The cost did not justify use and discard attitude. These bags were washable and reusable lasting for six months to a year.



Plastic and its Environmental Hazards:

The hazards plastics pose are numerous. The land gets littered by plastic bag garbage presenting an ugly and unhygienic seen. The "Throw away culture" results in these bags finding their way in to the city drainage system, the resulting blockage cases inconvenience, difficult in maintaining the drainage with increased cost, creates unhygienic environment resulting in health hazard and spreading of water borne diseases. This littering also reduces rate of rain water percolating, resulting in lowering of already low water levels in our cities. The soil fertility deteriorates as the plastic bags form part of manure remains in the soil for years.

It has been observed that the animals eating the bags sometimes die. Plastic goes into the ocean which is already a plastic infested body of water. Fish and other marine species in the water ways, misunderstanding plastic garbage as food items swallow them and die.

SHOULD PLASTIC BE TOTALLY BANNED?

Many household utility items like needle, scissors, and blades can heart if not handled properly. Children need to be trained in their proper handling. These utility items are not banned. But because of throw away culture and no objection from passer by, the advice on sensible disposal of plastic bags are not heeded by general public forcing the government to consider banning of plastic bags all together.

"Should plastic carry bags and bottles be banned in totality?" - is a heated issue today. World annual average is a alarming 18 kg. But too many do it as our cities have huge population. The country yet to take a serious view of the issue and have a uniform nation-wide law for indiscreet disposals of plastic bags. People should be educated on the proper ways of plastic bag usage and the disposal. The teaching should start right from the primary schools. Plastic is an eco-friendly material. The real problem is littering, some claim. But there is hardly anybody who agrees with such viewpoint.
Thinking rationally, the whole idea of educating people about plastic bags, although very ambitious, and it is as difficult as banning smoking The conventional older and tested alternatives offers an easy, if not fully equitable and practical solution.
And all the hype that poly-bags pollute is not totally false. It is not that poly-bags are responsible for the ills, of course not, it is the humans. It is ignorance (or who cares attitude). We have not banned sewing needles they pierce through the skin. It's a stupid idea. Whether it is the common citizen, the government official or the hard-hit plastic bag manufacturer, all of them agree on one point - firm steps are required to be taken against littering of plastic bags and bottles all around.

THE GLOBAL DIMENSION:

More than a 100 million tonnes of plastic is produced world-wide each year. Though plastics have opened the way for a plethora of new inventions and devices it has also ended up clogging the drains and becoming a health hazard. Many countries, including India, are trying to increase the amount of plastic that is recycled. But commercial interests create hindrance for effective legislation to remove plastics from goods where they can threaten public health. Also there is a clear trend of shipping off the plastic waste of developed countries to under developed and developing countries.
FUTURE ALTERNATIVE - ECO-FRIENDLY PLASTICS:

However newer technology is also being developed in this regard. This entails the use of DEGRADABLE PLASTICS. The principal is to incorporate into the plastic some chemical that is photodegradable/biodegradable or chemically treatable.

By adding starch, biodegradable plastics are generally made. On burial such plastics are attacked by bacteria feeding on starch, which breaks these down into tiny particles that disappear harmlessly into the soil. Some common examples of biodegradable plastics are the use of "non-removable" suture materials in surgery or capsules for drugs, which dissolve slowly in body fluids.

Chemically degradable plastics can be broken up by spraying them with a solution that causes them to dissolve. For example such material can be used as a protective wax covering for new cars that wash off at the dealer's garage by a specially formulated spray. This spray reacts with one of the components of the plastic and causes it to dissolve into harmless materials which can be flushed down the drain.

Photo-degradable plastics contain chemicals that slowly disintegrate when exposed to light. In France, strips of photo-degradable plastic about 3 ft (1mtr) wide are used to retain heat in the soil and produce early crops. They last for about 1 to 3 years before rotting into the soil. But they have to be used in places with consistent amount of sunshine so that they decay at a predictable rate. In the USA, about one quarter of the plastic yokes that link beer cans in a six pack are made of plastic called Ecolyte, which is photo-degradable. But to stop them decaying too early, they must be stored away from direct sunlight, which can be of some inconvenience to the retailer.

However degradable plastic can have a few other problems. For example, it cannot be recycled because there is no easy way to measure its remaining life span. The biggest drawback is the cost of its production. Japanese scientists however claim that they will soon be able to produce much cheaper multipurpose biodegradable plastic. In order to obviate the disposal problems and to prevent

Environmental pollution caused by routinely used polythene packaging materials; it would be prudent, for the present, to use eco-friendly paper packaging. The manufacturers of plastic packaging like soft drink bottles/mineral water bottles etc must come forward and develop appropriate methods of disposal/own responsibility for disposal.

Plastic bags are so light and strong that they can carry normal weight, cheap and is used in all types of shops in our daily life. For example: bakeries, medical shops, grocery stores, hotels, etc. People are so accustomed to it, that they find it very difficult to part with it. Plastic bags have made it possible for people to go without bags to market or work place as these bags are availably for asking and can be thrown without a second thought.

People who go on picnics, visiting historic places, hill stations etc., to enjoy their holidays or just for a change carry with them eatables in containers, plastic bags, mineral water bottles (plastic), plastic plates and plastic cups and generally leave it in the open air after consuming the contents. One can find this in tourist centres scattered all over. Road-side vendors also use plastic cups to serve coffee or tea. The customers throw these cups on foot paths or near drains after consuming the contents.

These plastic materials are so light that they are carried away by the speed of the moving vehicle, wind etc., scattered all over, making the surroundings look ugly. There are instances wherein these materials have clogged the underground drains. People are in the habit of throwing things they don't need wherever they like irrespective of the final result. People should be specially educated regarding the use of plastic in our daily life, as it is environment unfriendly. Boys and girls, men and women with bags on their backs and a stick in one hand walking long distances, picking up plastic waste, paper, bottles etc., from dust bins, road sides, is a common sight in our cities. These rag pickers sell the waste collected, to the collection centre to earn their livelihood. These materials are recycled.

The waste materials collected are of all types including plastic materials, such as plastic bags, plastic cups, plastic bottles etc. Instead of carrying these wastes away, they are burnt on the road side polluting the area with thick smoke which produce toxic gases (because of burning of plastic material) posing a health hazard. Inhaling of such gases causes lung diseases and even cancer. They resort to burning of waste material with the main intention of reducing the number of trips a lorry has to take. Plastic being non-degradable, when buried under the ground, arrest the percolation of water into the ground. Animals grazing in the field consuming this plastic waste along with grass cannot be ruled out. Now-a-days, in almost all functions, it has become a practice to use thin plastic sheets to cover the dining tables to give it a good look and also so that it is easy to clean the table, as left over can be removed by rolling the sheet at a stretch. These are thrown near the dust bin.

Besides this, thin plastic cups are also used for drinking water, which also finds a place in the dust bin. One can find near the dust bin, waiting slum children, crows, stray cows, dogs to share the leftovers. In this process, they fight amongst themselves and stray cows in majority of cases have consumed thin plastic sheets along with left over, leading to untold sufferings and also found dead on many occasions. It is therefore, suggested that a ban be placed on the use of plastic sheets, plastic cups, along with plastic bags. Plastic industries manufacturing plastic bags (below 20 microns) thin sheets, thin cups and thin bottles, should be informed about its ill-effects on the environment and advised not to manufacture such items. If the industry is located in a residential area, action should be taken to shift it immediately. The factory management should take all measures to control the pollution created, within the stipulated norms.

THE SOLUTION.

The solution lies in finding out:

1. Alternative suitable for making Bags and packing material at competitive rate and convenience without having any negative aspect.

2. Reaserch&Develpoment to make plastic more environments friendly.
3. Educate users to the right disposal methods.

4. Reduce the no of users by reducing the population in the long run.

5. Process vegetable, etc to higher density so as to reduce the no of bags required to pack and carry.

6. Encourage reusable bags from traditional materials by suitable advertisements to make it fashionable.

7. Cost of mfg bags with traditional material can be subsidized by printing advertisement on the bags.



Article Source: http://www.articlesbase.com/plastic-surgeries-articles/plastic-as-a-source-of-environmental-pollution-what-is-the-solution-610752.html



About the Author

Dr.Kedar Karki.M.V.St. Preventive Veterinary Medicine CLSU Philippines

Senior Veterinary Officer

Central Veterinary Laboratory

Tripureshwor

Kathmandu Nepal



Monday, February 8, 2010

Biodegredable Plastics - Transgenic Plants Providing a Solution

Author: G.S.L.Susmitha, Namrata Sengupta


BIODEGRADABLE PLASTICS

- TRANSGENIC PLANTS PROVIDING A SOLUTION

Almost every product we buy most of the food we eat and many of the liquids we drink come encased in plastic packaging, which provides excellent protection for the product. It is cheap to manufacture and seems to last forever. Lasting forever, however, is proving to be a major environmental problem. Plastics are manufactured from numerous non-renewable resources like natural gas, coal, and oil. Plastics cannot be degraded easily in the natural environment due to their long polymer molecules which are too large and too tightly bound.

A type of sturdy and hard plastic is made with a molecule known as Bisphenol A, BPA. BPA like many other man made chemicals is now detectable in most people’s blood streams and could cause dangerous hormonal changes in children. BPA may tend to cause cancer, early puberty, obesity and even attention deficit disorder.

To overcome this problem BIODEGRADABLE PLASTICS have been developed which are made from renewable resources, such as plants. Biodegradable plastics are made with plant-based materials and result in 15% less carbon emission. Infact biodegradable plastics have not been successful in replacing the wide spread use of traditional petrochemical plastics.

The following are few items and the time required for their decomposition,

Tin cans- 50 to 100 years

Aluminum Cans- 80 to 100 years

Glass Bottles- 1 million years

Newspapers- 25 to 50 years

Polystyrene- 1000's of years

Plastic bags- 400 years

So now we know the raising alarm being caused in the environment by the use of plastics. But a solution is always there,

"Green Film" Plastic Bags and Products- 9 months to 5 years .

The plastics that are decomposed in the natural environment are known as the “biodegradable plastics”. (‘Biodegradable’ means that a substance can naturally decompose with the help of micro organisms and will not persist in the environment beyond a certain period of time). The chemical bonds of biodegradable compounds are easily destroyed by a variety of bacteria over a small period of time to facilitate their decomposition. As early as in the year 1926, Lemoigne managed to isolate the first of the polyhydroxyalkanoates – polyhydroxybutyrate (a homopolymer whose building unit is the 3-hydroxybutyric acid) from the Bacillus megaterium bacterium. At the end of the 1950s, the presence of the polyhydroxybutyrate was confirmed as an energy and carbon source and storage in many other bacteria. Many species of bacteria accumulate polyhydroxyalkonoates as energy storage compounds, some of the PHA polymers are commercially valuable as biodegradable plastics.

Polyhyroxybutyrate is a PHA produced in Ralstonia eutropha via three enzyme bio synthetic pathway consisting of ? – ketothiolase, aceto acetyl Co-A reductase, and PHB synthase. PHB synthase production in plants was first demonstrated in transgenic Arabidopsis thaliana. Polyhydroxy alkanoates (PHAs), e.g., polyhydroxybutyrate (PHB), are synthesized from acetyl-CoA used as precursor, and are used for the synthesis of biodegradable plastics with thermoplastic properties. At present, PHAs are produced by bacterial fermentation, and the cost of biodegradable plastic is substantially higher than that of synthetic plastics.

Attempts are being made to produce PHAs in transgenic plants to reduce the cost. Genes encoding the two enzymes, aceto-acetyl-CoA reductase (PhbB) and PHB synthase (phbC), involved in the PHB synthesis from the precursor acetyl-CoA have been transferred from the bacterium Alcaligenes eutrophus and expressed in Arabidopsis thaliana. When the two enzymes were targeted into the plastids, PHB accumulated in leaves. PHB production by transgenic plants provides an example of a novel compound synthesized in plants.

Standards that certify biodegradability and compostability,

Following international organizations have established standards and testing methods for compostability: American Society for Testing and Materials ASTM ASTM 6400-99

European Standardization Committee (CEN) EN13432

International Standards Organization (ISO) ISO14855 (only for biodegradation)

German Institute for Standardization (DIN) DIN V49000

The ASTM, CEN and DIN standards specify the criteria for biodegradation, disintegration and eco-toxicity for a plastic to be called compostable. While ISO 14855 makes no stipulations regarding disintegrations or toxins remaining.

Dealing with plastic wastes has taken on significance not far short of ultimate redemption. Developing biodegradable plastics is just one of the solutions to the existing problem. Its our responsibility to remember that by the uncontrolled use of plastics we are contributing our share to a deadly pollution whose ill effects are irreversible and capable of reaching out to numerous generation to come.

REFERENCES

1. Nature journal, Nature Biotechnology.

2.Crop science journal.

3. India Together, Science and environment and environmental plastics.

4. Australian Academy of Science.

5. Eco Greenwares.

6. abc NEWS – Health

7. Institute of science and society



Article Source: http://www.articlesbase.com/science-articles/biodegredable-plastics-transgenic-plants-providing-a-solution-602078.html



About the Author