Starch based reactor, resultant products, and methods and processes relating thereto
1. The process of making a degradable starch-based resin comprising:
- peeling a starch-based plant feed stock selected from one or more Sago plants;
extracting a quantity of starch content from the peeled starch-based feed stock;
drying at least a portion of the quantity of starch content by substantially removing the water content from the starch content resulting in a base material in the form of a dried starch polymer;
processing the base material in a reactor into a quantity of soft starch polymer;
subsequent to the processing step, further polymerizing the soft starch polymer by combining and reacting in a reactive-extruder with maleic anhydride, a polyethylene-based plastic resin, a quantity of glycerol, and an oil to define a further polymerized starch, and;
partially cross-linking the further polymerized starch with the polyethylene-based plastic resin to form the degradable starch-based resin.
A process for making a starch-based resin from a starch-based plant feed stock generally comprising the steps of extracting starch content from prepared feed stock, preparing a dried starch from the extracted starch content that may be polymerized in a reactor with a catalytic material, a petroleum-based plastic resin, a quantity of glycerol, and an oil which is high in free hydrogen, and partially cross-linking the polymerized starch with a petroleum-based plastic resin to form a starch-based resin that may be used to produce starch-based film and bag products and other articles of manufacture that have unique degradation properties is disclosed herein.
|Starch-plastic composite resins and profiles made by extrusion|
Patent #US 20060194902A1
Current AssigneeGREEN DOT BIOPLASTICS LLC
Sponsoring EntityMGPI Processing Incorporated
|Method for Forming a Thermoplastic Composition that Contains a Plasticized Starch Polymer|
Patent #US 20130157031A1
Current AssigneeKimberly-Clark Worldwide Incorporated
Sponsoring EntityKimberly-Clark Worldwide Incorporated
- 1. The process of making a degradable starch-based resin comprising:
peeling a starch-based plant feed stock selected from one or more Sago plants; extracting a quantity of starch content from the peeled starch-based feed stock; drying at least a portion of the quantity of starch content by substantially removing the water content from the starch content resulting in a base material in the form of a dried starch polymer; processing the base material in a reactor into a quantity of soft starch polymer; subsequent to the processing step, further polymerizing the soft starch polymer by combining and reacting in a reactive-extruder with maleic anhydride, a polyethylene-based plastic resin, a quantity of glycerol, and an oil to define a further polymerized starch, and; partially cross-linking the further polymerized starch with the polyethylene-based plastic resin to form the degradable starch-based resin.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
This application is a U.S. National Stage application of International Application No. PCT/US2013/073364, filed on Dec. 5, 2013, which claims the benefit of Application No. 61/797,407, filed on Dec. 6, 2012, and titled Plastic Reagent and Process, and which are hereby incorporated by reference in their entireties.
1. Field of the Invention
The present invention relates generally to plastic bag and film products made from a unique starch-based resin derived from a starch-based feed stock, a compact reactor, and related processes and methods of manufacture. More specifically it relates to film and starch-based film and bag products that have unique degradation properties, which properties may include time-sensitive degradation qualities.
2. Background Art
It is commonly understood that typical plastic films, such as polyethylene, have a long degradation process, as long as 1000 years when buried in the ground. With the launch of the plastic grocery sack, many environmental concerns surfaced about this long degradation process. One approach to overcome this was the introduction of solar degradable grocery sacks that degraded rapidly in sunlight. For example the Solar Sack™ manufactured in 1989 by Polytec Packaging Systems had an expedited solar degradation time of as little as three to six months depending on the latitude, the season, and the amount of sun exposure. However, over time it was deemed that solar degradability was not a satisfactory environmental answer in most applications and to the many suppliers and sellers and users of products made of polyethylene.
Starch-based film and bag products were introduced in the early 1990'"'"'s and by the late 1990'"'"'s became commonly used in various industries to provide plastics with degradable properties, whether that is biodegradable, compostable, or otherwise. Since the late 1990'"'"'s starch-based films having biodegradable properties became commonly used in certain applications such as with mulch bags, whereas it is desirable to have the film degrade rapidly along with its compostable contents. For example, the content of a mulch bag may include compostable grass clippings, leaves, foodstuffs, certain organic wastes, and so on. Obviously the contents would be those that ideally heat up rather quickly in order to convert to mulch.
This particular use of degradable mulch bags is commonly used in several principalities throughout the United States, such as those in the Midwest, Illinois, Wisconsin, and Indiana. Likewise they are sold retail, such as the BioBag™, which claims it composts in a controlled environment in 10 to 45 days. The most common starch-based polymer used for this type of mulch bag and the like is corn.
A more recent emerging trend based on social responsibility is the use of degradable films in packaging bags, whether for carry-out bags in stores, or for retail packaging, which bags are considered inevitably targeted for disposal in landfills. This social responsibility has taken on various forms in various states and certain laws have been mandated to adopt this new emerging trend. For example, in California packaging products used for padding and loose filler in cartons and bags for shipping goods, must be degradable. A report by Time magazine estimates that less than 1% of retail bags are ever recycled.
Today a myriad of companies and states trying to address the emerging degradability issues with carry-out bags, retail packaging, and so on, have instituted various requirements and specifications for degradability, all of which include the use of starch-based resins in one form or another, and many of which are inadequate for addressing the real issue of degradability. For example, BASF produces a resin under its trade name EcoFlex™. It is an aromatic-aliphatic co-polyester. It is made by polymerizing two different molecular structures, an aromatic with natural properties of being too “springy/spongy” so it is co-polymerized with aliphatic to give it some strength. They are a partially cross-linked polymer. It tends to degrade well because the energy stored in the aromatics is triggered by lower-energy-state enzymes by common bacteria. The biggest problem with the Eco-Flex resins is that it is not made from a renewable base material. Renewability is becoming an increasingly important issue environmentally and an important requirement in consumer applications. Another problem with the Eco-Flex process is that it is inherently more expensive to produce as it requires a number of additional stages of production. First the aromatic polyester is created, second, the aliphatic polyester is created, and third the two elements are then partially cross-linked. The resultant material is inherently softer than traditional materials it is intended to replace and has significant stretch characteristics, even if the material is extruded as a significantly thicker film. The excessive stretch characteristics are generally undesirable in most plastics applications, thus, Eco-Flex materials are inappropriate for many, if not most plastic products. Last, the softness of the film makes the material difficult to extrude in thinner gauges, for example 50 microns up to 120 microns, therefore thicker gauges require substantially more material, which greatly increases raw material usage and cost. It goes without saying that increased raw material usage is counterproductive to improving its overall environmental footprint.
An attempt at a resin made from a renewable raw material comes from Brazil. The Braskem resins are made from sugar, which are completely polymerized such that the polyester they create is identical in properties to regular polyethylene, in other words, it degrades in 1000 years. The point of this resin is to avoid being captive to imported oil, to make it renewable although that is debatable. The main problem with Braskem'"'"'s sugar-based polyester, in addition to the fact it is not considered degradable, is that it is limited to a raw material base of sugar, which is not plentiful in most parts of the world. The molecular structure tends to be very close to polyesters made from petroleum and shares similar characteristics of petroleum based polyesters, but their only environmental claim is renewability of its raw material feed stock, sugar. This claim for renewability, however, is partially offset by the greater energy requirements for the production. This is substantiated with a Life Cycle Analysis methodology that takes into account not only the raw material inputs (sugar) but also the fossil fuels and other forms of energy that are required for material conversion. Because of the requirement of these additional inputs for production, the product cannot claim to be made of renewable materials per se.
In addition to the Braskem and Eco-Flex resins, common additives made from cornstarch create a myriad of problems. These prior art technologies consist of Polyhydroxyalkanoate (PHA) and its related materials, PHB, PHBV, PHBHx, PHBO, PHBOd), and so on. These PHA-based materials carry brands such as Metabolix™ (PHB, PHBV) made by Metabolix/ADM, USA; Biopol™ (PHB, PHBV) made by Monsanto-Metabolix, USA; Enmat™ (PHB, PHBV) made by Tianan, China; Biocycle (PHB, PHBV) made by Copersucar, Brazil; Biomer L™ (PHB, PHBV) made by Biomer, Germany; and Nodax™ (PHBHx, PHBO, PHBOd) made by Procter & Gamble, USA.
PHA resins and its related materials are produced from specific starches that are corn derivatives. The typical starch base material is Amylopectin. In addition to inputs of specific starch materials, large inputs of water and electricity are required. The base material is converted metabolically by ingestion by genetically engineered microbes (also referred to as GMOs or “genetically modified organisms”), which consume the base material as a food source and excrete materials which can be polymerized after sufficient purification. A major problem with this process, unknown by many environmentalists, is that the extensive energy and water requirements are costly. Likewise, this process produces significant amounts of waste materials such as bio-mass of expended microbes that are wasted during production. The process is dependent on genetically modified organisms both on the production of base materials and on material conversion. Generally speaking this process increases energy requirements (usually from petroleum fired plants) since the corn must be processed, dried, and converted prior to conversion into resin.
While the use of GMOs is not restricted in the US, there is considerable concern worldwide about the proliferation of genetically modified crops with mainstream agricultural production. Europe has raised high levels of concern whereas the United States, driven by the economics and politics of agricultural concerns, has legislated few restrictions. While the potential dangers related to the use of GMOs are not presently available, the use of non-GMOs, would certainly represent a safe alternative. In some regions powerful consumer-groups are heavily advocating to ban all GMO crop-materials and promote only non-GMO crop materials.
The typical manufacturing process of PHAs includes: 1) Production of farm corn crops using standard, high volume crops, which crops are dependent on petroleum as raw material inputs in fertilizers and production machinery; 2) Drying and delivery of corn crops to a processor; 3) Grinding/milling, extraction of starches from the corn using substantial hot water solutions and complex, expensive, time-consuming purification methodologies; 4) Introduction of purified starches into bioreactor vats and inoculation with yeast, potentially dangerous e-coli or other GMO microbes, thus growing the microbes to target densities; 5) Purifying the excreted base materials by removal of the bio-mass and extraneous proteins, starches, plus a variety of other waste byproducts, and; 6) Polymerization of excreted base materials to produce resin suitable for manufacturing.
Another cornstarch based technology in addition to the PHA technologies are the prior art technologies referred to as Polylactic acid (PLA). Typical brands are Natureworks™ made by Cargill, USA; Lacty™ made by Shimadzu, Japan; Lacea™ made by Mitsui Chemicals, Japan; Heplon™ made by Chronopol, USA; CPLA™ made by Dainippon Ink & Chemical, Japan; Eco Plastic™ made by Toyota, Japan; PLA™ made by Galactic, Belgium; Treofan™ made by Treofan, Netherlands; L-PLA™ made by Purac, Netherland; Ecoloju™ made by Mitsubishi, Japan, and; Biomer L™ made by Biomer, Germany.
PLA resins, like its counterpart PHA, is typically made using the corn-derived starch with its base material Amylopectin. Like PHA, it also requires substantial water supplies and excessive energy in order to be produced. The base material is converted metabolically by ingestion by genetically engineered microbes which consume the base material as a food source and excrete materials which are then polymerized after sufficient purification. The energy intensive process produces substantial amounts of waste materials such as bio-mass of expended microbes. Like the PHA process, the PLA process is dependent on genetically modified organisms both on the production of base materials and on material conversion. The primary difference between PHA and PLA is that Lactic Acid is the byproduct used to produce PLA resin.
The typical manufacturing process of PLA includes the following steps: 1) Production of farm crops using standard, high volume corn crops, which crops are dependent on petroleum as raw material inputs in fertilizers and production machinery; 2) Drying and delivery of corn materials to a processor; 3) Grinding/milling, extraction of starches through hot water solutions and purification processes; 4) Introduction of purified starches into bioreactor vats and inoculation with yeast, potentially dangerous e-coli or other modified microbes, thus growing microbes to target densities; 5) Purification of excreted Lactic Acid by removal of bio-mass and extraneous proteins, starches, variety of other materials, and; 6) Polymerization of the excreted Lactic Acid to produce resin suitable for manufacturing.
The use of PHA and PLA resins in manufacturing film products, bags and so on have traditionally required gauges up to three times thicker than that of petroleum based products. In the film and bag making process, this equates to more costly extrusion outputs, slower conversion times, three times the storage space, three-fold shipping costs and so on. Thus, products made from these methodologies must be either those that require heavier gauges or where strength qualities are not important.
When products made from PLA and PHA resins are buried in a landfill or otherwise, they are consumed by a narrow range of bacteria, particularly ones that release protease enzymes. Thus, the question is raised of whether or not the environment in which they are buried is suitable for degradation.
Generally speaking, all cornstarch plastics tend to cause additional problems and expenses when extruded. This is primarily due to the fact that extruding a product three times thicker than a traditional plastic film requires more energy. The cornstarch based resin products are also more difficult to extrude with inferior bubble stability compared to traditional films. This results in the need to have a more highly controlled manufacturing environment and a higher waste output. Substantial know-how is required in order to adapt an extruder to extrude corn-based resins and produce films to convert into bags and so on. Likewise, conversion of cornstarch plastics is a slower process with more down time on conversion equipment in order to change roll stock and replace sealing components such as Teflon covers where residue tends to build up more quickly than traditional plastics. Thus, the overall end result with cornstarch-based plastic products is substantially higher costs, including energy to manufacture and ship. For example, the retail price of a common 33 gallon BioBag is about $0.85 to $0.95 per bag depending on quantity, whereas the price of a comparable bag made from regular polyethylene is about $0.09 to $0.15 each. The inherent cost of the product and its production processes has made market acceptance very limited. The minimum inputs in materials, energy for conversion through its various required stages of heat, fermentation, purification, and polymerization are costly, as is the infrastructure required to support it. The overall cost therefore is inherently too high for adequate marketability and penetration.
It is clearly understood in the industry of degradable plastics that the primary alternatives to petroleum based resins are dominated by corn, which conversion processes raise serious questions as to sustainability. Without question, the substantial increase in transportation, excess use of energy and water to convert and manufacture raise serious economic questions and new environmental questions altogether. The questions include the ability to consistently degrade, or perhaps if degradation even occurs. It is understandable that these methods are inadequate when addressing the true nature of environmentally sound plastics and their related products based on present costs, waste of energy, waste of precious water supplies, added transportation costs, the required use of petroleum products to produce and convert, let alone the questionable use of GMO microbes and their inherent waste.
The use of degradable starch-based film, bag, and other plastic products that overcome the numerous problems associated with prior art would be valuable to these trades and many others.
The film, bag, and other plastic products made from the starch-based resin of the present invention overcomes the problems associated with prior art. The starch-based resins are produced on a compact reactor and subsequently require virtually no adjustment to extruding and converting operations as required by the cornstarch-based resins. Unlike all prior art starch-based plastics, the present invention may be made of a Tapioca root based resin in a reactor that substantially reduces energy requirements, and the subsequent energy requirements in bag making and converting processes. The starch-based resin is typically made from Amylopectin-rich Tapioca, Sago, or other related non-GMO feed stock. Thus, the resin is manufactured from a truly renewable resource.
The bag and film products of the present invention may be manufactured on traditional extrusion equipment and converted on standard bag making machinery with few, if any, changes or modifications. In other words, manufacturers of virgin polyethylene plastic products will be able to quickly adapt to the extrusion and conversion of the products made from the Tapioca resin of the present invention, regardless of the fabrication of film into bags on rolls, stacked bag products, bottom seal or side weld, plastic injection products and so on.
The resins of the present invention are manufactured with a unique process that cross-links the Tapioca polymers. This unique method controls the cross-linking between the Tapioca starch chains and the PE chains thus allows the material to have properties almost identical to LDPE but still allows enough bio-availability of the starches such that it rapidly biodegrades in most environmental conditions.
Additional benefits to the present invention include its ability to produce the Tapioca resin in a far more efficacious manner than corn-based resins. This significantly reduces resin costs and substantially reduces energy and water requirements. The result is a versatile resin that may be subsequently cost effectively manufactured and converted into film, bag, and other plastic products. Likewise, the degradation qualities of the present invention are significantly superior to corn-based resins, as the present invention degrades with a broader range of microbes.
Converted products made from Tapioca-based resins of the present invention may be effectively stored for long periods of time, for example in a warehouse, which is advantageous to distributors and retailers. In comparison, questions have been universally raised as to the degradation and loss of strength of corn-based plastic products in a warehouse storage environment. In one test of bag products made by Ecoplas™ film, which uses the Tapioca resin of the present invention, after storage for five years, the loss in strength is considered as negligible.
Tapioca-based resins of the present invention are not only recyclable but may be recycled with other LDPE plastics because reprocessing is identical. With an increasingly social-conscious marketplace the Tapioca-based resins may be sold openly in the marketplace without being tied down to a certain region of the world. Raw material may be purchased from a wide variety of basic farming operations and various regions in the world due to the flexibility of the production process. Last, it has a low carbon footprint.
The objectives of the present invention are to provide:
1) A reactor that converts starch into a polymer.
2) A reactor that converts starch into a biodegradable resin.
3) A reactor that converts Tapioca into a biodegradable resin.
4) A method of conducting business in localized regions.
5) A method of producing resin from non-GMO starch-based feed stock.
6) A method of producing resin in a localized region, using a compact reactor.
7) A compact reactor that produces a polymer resin in a localized region with properties that are specific to that region.
8) A Tapioca-based resin that is cost effective.
9) A Tapioca-based resin that is cost effective to manufacture.
10) A Tapioca-based resin that is cost effective to extrude into film.
11) A Tapioca-based resin that is cost effective to convert into film products.
12) A Tapioca-based resin that may be extruded using present manufacturing processes.
13) A Tapioca-based resin that saves energy to extrude.
14) A Tapioca-based film that may be converted without applying new technologies.
15) A Tapioca-based film product that has excellent strength qualities.
16) A Tapioca-based film product that has excellent printability.
17) A Tapioca-based film that effectively degrades.
18) A Tapioca-based film product that has excellent degradation qualities.
19) A Tapioca-based film that may be effectively stored for long periods of time.
20) A Tapioca-based film product that may be converted into bags.
21) A bag made from Tapioca-based film that is suitable for carrying merchandise.
22) An article made from Tapioca-based film.
23) An article made from Tapioca-based resin.
24) An injection molding article made from Tapioca-based resin.
25) A blow molding article made from Tapioca-based resin.
26) A compression molding article made from Tapioca-based resin.
27) A vacuum formed article made from Tapioca-based resin.
28) An article made from Tapioca-based film that is suitable for carrying merchandise.
29) An article made from Tapioca plastics containing one or more foaming agents.
30) An article made from Tapioca plastics containing one or more foaming agents, suitable for use in food trays, or packaging cushion applications.
It will be appreciated that all of the exemplary objectives listed herein are not required to be met by the present invention or any embodiments described herein and that a smaller subset of such objectives may be met by any such embodiments described herein.
Furthermore, it is an object of this application to illustrate the preferred embodiments and broadly state the methodologies that may be used in order to manufacture film and bag products and articles made from resin of the present invention. Other aspects of the present invention will become apparent with further reference to the following drawings and specification.
A. Description of the Reactor and the Resin Manufacturing Process
The base material (feed stock) 50, in the form of a dried starch, a naturally occurring polymer, is then processed in a reactor into a soft starch polymer 60 consisting of essentially 100% starch (containing some natural impurities). Subsequent to the processing step, the soft starch polymer 60 is then input into a reactive-extruder 70 and further polymerized with specifically formulated materials, such as maleic anhydride to be used as a compatibilizer C (
The resins as processed according to
The reactor of the present invention may be substantially large such as those commonly used by major entities such as Exxon/Mobil, Mitsui, and Philips, Ltd. Their typical reactors for large volume mass market PE resins would be as large as one-quarter mile long. In sharp contrast the unique reactor of the present invention may be as short as 100 feet to 150 feet long. This compact size enables a unique business model that may be conveniently located near starch-based feed stocks, such as Tapioca and Sago palm.
Being in a regional locale that grows a suitable feed stock substantially lowers production costs, by reducing transportation costs. It also provides for efficacious adaptation of a local feed stock. For example, a feed stock in one region of Indonesia may have a higher starch content with more impurities than a similar feed stock in Africa or the United States. The ability to change, modify, and adjust the additives and processes of the compact reactor of the present invention to the feed stock of a particular locale may be quickly completed with minimum waste. This unique adaptability of the compact reactor may provide local employment throughout the world, including third world nations. Vast regions, in particular those located in the tropical regions, with substantial unemployment, and which have substantial feed stock may benefit by locating a compact reactor nearby.
The compact reactor of the present invention also costs a fraction of that of the traditional mega-giant reactors, as little as 1/1000 of the cost. Locating inexpensive compact reactors throughout a country'"'"'s farming region may suddenly become a profit center replacing a depressed economy. The result is a business model that provides income to some of the poorest people in the world.
Due to the simplicity of the reactor'"'"'s design, and its compact size, highly skilled technicians are not required. Training operators with a relatively low level of education is viable with the present invention.
Likewise, based on the exceptional environmental qualities of the resin of the present invention, there is minimal impact on the local environment. Products made from resins of the reactor of the present invention, may be profitability recycled, or may be allowed to biodegrade in landfills.
Perhaps of greater importance are the facts that the reactor operates with a very low energy requirement, normally attainable in rural locales in third world nations, and; the feed stock such as Tapioca, Sago, and so on, are all genuinely renewal, non-GMO feed stocks. These factors create a highly usable resin for blown films, injection molding, vacuum packaging and so on, that is substantially more cost effective then prior art resins. For example, all other degradable prior art resins cost 200% to 300% more than their virgin polyethylene or polyester counterpart. As disclosed herein, the prior art resins have inferior strength qualities, which generally ratchets up the ultimate cost of a finished product as much as ten times that of products manufactured from resin of the present invention.
Of great importance, the reactor and its process requires a fraction of the water, approximately 5% of that required by fermentation based, corn-based prior art. It also uses a fraction of the electricity of the prior art production, approximately 15% of the power required by fermentation based resins, and about 50% of those used in other processes.
B. Description of the Extrusion and Conversion Process
Since the qualities of the resin of the present invention mimic essentially the same qualities as standard PE resins, there may be few requirements, if any, to make additional modifications to extrusion processes in order to manufacture film of the present invention. Essentially the same extruders, dies, screws and silage are used as with common PE resins. All equipment used for winding up rolls, standard or jumbo, remains the same. Cooling temperatures remain the same and requirements for slip and anti-block also remain essentially the same. Tensioning during wind-up goes unchanged. Surprisingly, even the film orientation qualities remain unchanged.
The properties of the film of the present invention have been processed repeatedly by several third party extrusion companies, thus consistently validating manufacturing qualities and results. Tests conducted in cooperation with a major recycling operation, PT Rodaperdana Utamakary, Jakarta, Indonesia, evaluated the film of the present invention and standard PE regarding various qualities and percentages throughout an entire production cycle, involving recapture, re-pelletizing, and production of new film materials. The film of the present invention performed in an identical processing methodology in all aspects of production as did standard PE. The only minor change that was noted was the ability of the film of the present invention to be extruded, processed, at a slightly lower temperature. Production reports consistently reveal that the extrusion temperatures may be lowered by approximately 5-10 degrees C., thus providing a substantial energy savings. While it may not appear to be huge, extrusion equipment is notorious for consuming large amounts of energy, thus a small 10%-20% savings is indeed substantial.
Essentially the same conversion equipment, bottom seal, side weld, back-seal, slit-seal operations and so on are used with a direct changeover from standard PE film to the Tapioca-based film of the present invention. Film products of the present invention, such as bags, film converted into die-cut articles, such as plastic gloves, aprons, capes and so on may be effortlessly converted on existing conversion machinery without special considerations. Products manufactured from Tapioca film of the present invention have substantial shelf-life, durability with the desired rip and tear resistance, and the desired pre-determined qualities. Unlike certain corn-based resins that tend to “yellow” when stored in warehouses after several months due to their degradation qualities being initiated, the film products of the present invention will not initiate degradation. The degradation is biological so the materials will only begin to degrade in environments where they are exposed to conditions favorable to microbial growth such as soil, ponds, or composts.
To convert film products of the present invention no additional modifications are required, such as, heating temperatures, pressures, and dwell time for sealing. Nor are adjustments required for roller coverings, gusseting apparatuses, slit sealers, or blow down for stacking bags. Flying knives for cutting film articles remain unadjusted, edge guides throughout do not require modification, and so on. Unlike prior art, the direct conversion of articles converted on a piece of machinery from standard PE film to film of the present invention runs effectively at the same cycle speeds with no loss of production or no loss of downtime for unnecessary readjustments.
C. Strength Qualities
The strength qualities of the present invention may be formulated to meet or exceed the physical properties of prior art LDPE films. When compared to corn-based films, the strength properties of films of the present invention are far superior. For example, gauge for gauge, film products of the present invention tend to be two to three times stronger than corn-based resins. However, one of the greatest versatilities of the present invention is that the cross-linking that occurs in the secondary reactor 70 as outlined in
The primary reason the reactor of the present invention may be easily adapted to various strength qualities is due to its compact size. Adjusting batch qualities and inputs of the standard PE resin, as well as other additives commonly used in the plastics industries, is efficacious with the reactor of the present invention generating minimal waste during changeovers.
An example of applying this unique flexibility to produce a desired film structure and maintain the environmental, biodegradable properties may be a shopping bag for Target® Stores, whereas the Tapioca content may be reduced to 25% with a larger amount of PE (approx. 74%) plus other natural ingredients (1%). This provides a stronger film that can be blown in very thin gauges (well under 1 mil) and it is essentially identical to a LLDPE blend that Target would otherwise use (the present blend is with high density PE and low density PE). As explained in
D. Degradation and Environmental Qualities
The Tapioca resin and film based products of the present invention have substantially more favorable degradation qualities than prior art. Due to a starch base that is bio-available, it is eaten in its first stage by a myriad of microbes: molds, mildews, fungus of many sorts, and most common bacteria types. Unlike prior art that must rely on a narrow range of microbes to initiate their degradation processes, the resin of the present invention may begin degradation in far more common environments, including a broad range of temperatures, climate zones and humidity ranges. Regardless of whether a film based product of the present invention is discarded as trash in a trash dump, disposed as litter, or even disposed into a river or lake, true biodegradation takes place.
As illustrated in
Tapioca-based resin products of the present invention are also considered “animal safe”. In other words if accidently eaten by an animal, it will not cause death. An independent study conducted by Bagain Patologi, Bogor, Indonesia revealed that a composition of 50% feed and 50% resin of the present invention does not cause animal death. Tests in fifteen mice caused neither deaths nor lesions to the intestines or gastric system and the product was completely digested. With standard PE, two of the fifteen mice consuming a 50%150% mixture resulted in death, and in all test mice it resulted in the gastric tract blunting villi, proliferation of inflammatory cells, with dysphasia of epithelial mucous. The regular PE was only partially digested.
The resin of the present invention is also recyclable and may be melted and pelletized. Pt. Rodperdana Utamakarya, of Jakarta, Indonesia, a third party, verified recyclability in its test conducted May 7, 2010. Its results throughout the entire recycling process revealed “no observable affects occurred in the process including machinery.”
In conclusion the resin of the present invention made with the process of the present invention on the reactor of the present invention excels in all aspects of environmental qualities.
The spirit of the present invention provides a breadth of scope that includes all methods of making and using it. Any variation on the theme and methodology of accomplishing the same that are not described herein would be considered under the scope of the present invention.