WO2010107402A1

WO2010107402A1 - Hemicellulose based anti-microbial anti-fog biodegradable film capable of removing undesired gases and production method thereof

Info

Publication number: WO2010107402A1
Application number: PCT/TR2009/000089
Authority: WO
Inventors: Ufuk Bakir
Original assignee: Ufuk Bakir
Priority date: 2009-03-17
Filing date: 2009-07-14
Publication date: 2010-09-23
Also published as: WO2010107402A8

Abstract

The present invention relates to a hemicellulose based film and/or coating material composition and the production stages for making the film and/or coating material used in the packaging of fruits and vegetables in which the film and/or coating material is produced from agricultural wastes such as cotton stalk, sunflower stalk, corn cob, stalks and brans of various cereals such as wheat, oat, barley, hazelnut shell or forestry wastes such as saw dust wherein said film and/or coating material is anti-microbial, anti-fogging and capable of removing undesired gases.

Description

HEMICELLULOSE BASED ANTI-MICROBIAL, ANTI-FOG BIODEGRADABLE FILM CAPABLE OF REMOVING UNDESIRED GASES AND PRODUCTION METHOD

THEREOF

Field of the Invention:

The present invention relates to a hemicellulose based film and/or coating material composition and the production stages for making the film and/or coating material used in the packaging of fruits and vegetables in which the film and/or coating material is produced from agricultural wastes such as cotton stalk, sunflower stalk, corn cob, stalks and brans of various cereals such as wheat, oat, barley, hazelnut shell or forestry wastes such as saw dust wherein said film and/or coating material is anti-microbial, anti-fog and capable of removing undesired gases.

Prior Art: According to the prior art, films which are used for the packaging of food stuffs are generally manufactured from petrochemical based polymers such as polyethylene or polypropylene.

As very well known petroleum is not a renewable resource and it is predicted that the petroleum reserves in the world will deplete approximately within 50 years. Furthermore, the production of petroleum based chemicals and materials cause environmental pollution. Additionally upon the end of their usage, plastic materials such as polyethylene and polypropylene remain in the environment without being degraded for hundreds of years. These issues have brought up the usage of biodegradable polymers manufactured by environmentally friendly technologies. Biodegradable plastics or in another words, bio-polymers can be obtained from biologic systems such as biologic materials or microorganisms as well as petrochemical raw materials.

Polylactade (PLA), polycaprolactam (PCA), chitosan, starch, cellulose and polyhydroxyalkanates (PHAs) are some examples to the biodegradable polymers used in the prior art. In some of the polymers mentioned above (such as PLA) the manufacturing costs are high or as in the case of starch, raw materials such as corn or potato that possess nutritional qualities are being used during the production. Ethically, the consumption of food stuffs during the production of biodegradable films is controversial.

High manufacturing costs and the utilization of food stuffs as raw materials during the production prevent the widespread use of these biodegradable polymers.

Despite hemicellulose based films, especially xylans, obtained from lignocellulosic (comprised of mainly cellulose, hemicellulose and lignin) materials are present in the prior art, the number of such films are limited.

In prior art, WO 2004 083286 Al discloses the composition of a polymeric film which can be used as an oxygen barrier and the acquisition of the film formation property by the hemicellulose used for coating purposes. Polymeric film disclosed in WO 2004 083286 Al is composed of a xylan derivative hemicellulose with a molecular weight between 8000 - 50000 g/mol, a plasticizer composed of sorbitol, xylitol or water and an oligomer or a polymer.

Polymeric film disclosed in WO 2004 083286 Al does not utilize any agricultural or forestry wastes as a raw material. Additionally the said polymeric film does not possess antimicrobial and antifogging characteristics.

In prior art, WO 2008 0103123 A2 discloses a packaging film containing hemicellulose, plasticizer, cellulose and an oligomer or a polymer.

Polymeric film disclosed in WO 2008 0103123 A2 contains a crosslinking agent that can interact with carboxyl or hydroxyl groups in order to increase the resistance of the said film against liquids and humidity.

The polymeric film disclosed in said document does not utilize any agricultural or forestry wastes as a raw material. Additionally the said polymeric film does not possess antimicrobial and antifogging characteristics.

CN 101298483 A in prior art discloses a modified hemicellulose via acylation and the production method of the said modified hemicellulose.

The hemicellulose disclosed in CN 101298483 A is exposed to an acylation reaction in the presence of microwave irradiation creating a hemicellulose ester structure. This ester structure is used in the production of biodegradable packaging materials.

The biodegradable film disclosed in CN 101298483 A which is obtained from modified hemicellulose does not contain any antimicrobial nanoparticles as well as any nanoparticles that will prevent the permeation of undesired gases. It is known that the raw material used in CN 101298483 A is hemicellulose based however there is no information indicating the source of the hemicellulose to be an agricultural or forestry waste.

In the known technique, EP 0506650 Bl discloses a film produced for packaging applications and the production method of the said film.

The film disclosed in EP 0506650 Bl is polysaccharide based. Chemical-thermal and/or enzymatic/thermal or mechanically produced biodegradable film is composed of 25% agricultural wastes, preferably 50% cellulose, hemicellulose, lignin, pentosan and pectin and maximum 30% water by means of its total mass. The article published in The Journal of Agricultural and Food Chemistry (2007,

55) by the applicant is related with an experiment conducted in order to obtain a biodegradable film with desired thickness and mechanical properties and the chemicals and the conditions employed during this experiment.

The article published in The Journal of Agricultural and Food Chemistry (2007, 55) by the applicant explains the production of biodegradable films only in laboratory conditions and is not related with the production of the said films on industrial scale.

Furthermore in the above mentioned article published by the applicant, the raw material used for the production of biodegradable film is limited to cotton stalk which is an agricultural waste. In the article published by the applicant the choice of raw material for the production of biodegradable film is not enhanced to include other various agricultural wastes or forestry wastes. Additionally the film to be produced is not mentioned to be coated with certain chemicals that will render the film anti-microbial, anti-fogging and capable of removing undesired gases. By general means, the article published in The Journal of Agricultural and Food

Chemistry (2007, 55) by the applicant explains that cellulose and lignin can be removed from cotton stalk which is an agricultural waste and a biodegradable film can be produced from the remaining xylan structure.

Summary of the Invention:

A different application of the present invention is conducted on laboratory scale and examples related with the production of biodegradable films under laboratory conditions, containing only the xylan fraction obtained from cotton stalks and sunflower stalks and no other polymers are listed below.

Example 1: (Film formation, solvent casting) This example is related with the production of biodegradable films, containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk, by solvent casting technique. 20 grams of cotton stalk, pretreated at 60 ⁰C for 16 hours with water, is added to an alkali solution of l%NaBH₄ (w/v) and %24 KOH (w/v) and stirred at room temperature followed by the addition of ethyl alcohol containing 10% (v/v) acetic acid in order to precipitate the lignin containing glucuronoxylan which was then centrifuged and dried to obtain the main polymer of the film. 0.6 grams of this substance was dissolved in 25 ml. of water and poured into plastic petri dishes of 9 cm diameter. Upon drying films with 60 μm thickness were obtained.

Example 2: (Film formation, thermal press)

This example, is related with the production of biodegradable films, containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk, by thermal pressing. 1.5 grams of glucuronoxylan, obtained in the same manner as described in example 1, is pressed in a thermal press at a temperature of 105⁰C with 10000 pound-force for 10 minutes. Films with 150μm thickness were obtained.

Example 3: (Permeability, H₂O)

This example is related with the water vapor transmission rate of the biodegradable films containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk. Films obtained as described in example 1 are mounted on top of bottles containing silica gel granules and these were placed inside a controlled chamber (MMM Group Climacell) at 25°C and 85% relative humidity and the rate of water vapor permeability is measured. In these conditions the water vapor transmission rate of the glucuronoxylan based films with 60 μm thickness were calculated as 103 g/day.m² Example 4: (Antimicrobial, TiO₂ powder)

This example is related with the acquisition of photocatalytic activity by biodegradable films, containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk, upon the addition of TiO₂ in powder form. 1 gram glucuronoxylan, obtained as described in example 1, is dissolved in 30 ml. of water followed by the addition of 0.1 gram TiO₂ in powder form into the solution. The solution is ultrasonicated for 20 minutes and poured into plastic petri dishes with 9 cm diameter and dried at room temperature. Upon drying bacteria {Escherichia coli) grown in appropriate conditions were placed on the films and films were placed under a 2OW black light with a peak wavelength of 367nm (GE Black Light), distance between the films and the light source being 10 cm. The same procedure is applied for the non TiO₂ containing films, which are synthesized as described in Example 1. At the end of 1 hour bacteria were collected from films with and without TiO₂ and upon appropriate dilutions bacteria were spread onto the agar plates. By counting the colonies on the agar plates and by comparing the number of colonies obtained from each type of film it was calculated that the films containing TiO₂ had a 100% antimicrobial activity against Escherichia coli.

Example 5: (Antimicrobial, Sol-gel coating)

This example is related with the acquisition of photocatalytic activity by biodegradable films, containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk, upon sol-gel coating. Films obtained as described in example 1 or example 2 are dipped into an ethanol based sol-gel synthesized from TTIP precursor for 15 minutes followed by drying at 60⁰C for 5 minutes and treated at 105⁰C for 15 minutes. Upon these procedures film were tested for their antimicrobial activity as described in Example 4. Upon comparison of colony numbers obtained from the coated ad non-coated films, it was calculated that films had 90% antimicrobial activity against Escherichia coli at the end of 2 hours.

Example 6: (Antimicrobial, Phenolic) This example is related with the acquisition of antimicrobial activity by biodegradable films, containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk, upon addition of phenolic compounds isolated from agricultural wastes. Films are produced by the addition of carvacrol or thymol or tannic acid to the film forming solution obtained as described in Example 1. Then the films are obtained in a method as described in Example 4. The antimicrobial characteristics of the film are determined by keeping Escherichia coli on the film for one hour followed by the determination of the number of viable microorganisms. At the end of the analysis film were found to possess 100% antimicrobial activity against Escherichia coli.

Example 7: (Ethylene degradation)

This example is related with the photocatalytic reduction of ethylene gas by biodegradable films containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk. Film obtained as described by example 4 or example 5 are placed inside a glass cylinder closed with KBr plates at both ends followed by the injection of 66 ml. of air containing 1% ethylene gas. The glass cell containing the film is exposed to a light source with a peak wavelength of 254nm for 3 hours. At the end of each hour the quantitative properties of the gases inside the glass cell against time is investigated by placing the glass cell into a FTIR device (Bruker Equinox 55) by considering the characteristic peaks of the gases within a wawelength of 400 - 4000nm. At the end of the investigation, by considering the peaks appearing in the specific regions of the spectrum that correspond to the CO₂ gas and C - C and C = C bonds, degradation of the ethylene gas and accumulation of CO₂ gas was observed.

Example 8: (Biodegradation)

This example is related with effect of acquisition of photocatalytic activity by the biodegradable films on their biodegradation under soil for the films containing no plasticizers and no other polymers except the xylan fraction obtained from cotton stalk and sunflower stalk. Films obtained as described by example 4 or example 5 are buried into soil in an isolated environment and the amount of CO₂ gas evolving from the films as a result of the biodegradation process are determined by titrating the KOH solution, which traps the evolved CO₂ gas, with HCI. The same procedure was also followed for the films which do not possess photocatalytic activity and obtained as described by Example 1 or Example 2. By comparing the CO₂ gas evolved from the films, it was calculated that films possessing photocatalytic activity produced 16% more CO₂ compared to the films with no photocatalytic activity.

The present invention, which relates to a hemicellulose based biodegradable film and/or coating material composition in which the film and/or coating material is produced from agricultural wastes such as cotton stalk, sunflower stalk, corn cob, stalks and brans of various cereals such as wheat, oat, barley, hazelnut shell or forestry wastes such as saw dust wherein said film and/or coating material is anti-microbial, anti-fogging and capable of removing undesired gases, aims the following: • utilization of idle agricultural and forestry wastes found in nature.

• lowering the production cost of biodegradable films by the utilization of cost-free raw materials such as agricultural and forestry wastes.

• production of a biodegradable packaging material with a high water vapor permeability. • production of a packaging material with antimicrobial and antifogging characteristics.

• improvement of food packaging materials by making these materials microorganisms free due to its antimicrobial characteristic.

• prevention of environmental pollution caused by similar packaging materials since it is produced from totally natural materials and spontaneously degraded in nature upon the end of its usage.

• variation of permeability of gases such as oxygen and ethylene by the addition of plasticizers into its structure.

• removal of ethylene gas formed within the packaging material by photocata lytic means due to its high water vapor permeability and the antimicrobial chemicals it contains.

• Enabling the production of goods other than packaging materials by utilizing the most worthless parts of agricultural and forestry wastes.

• Application as a coating to cardboard, paper, plastic or directly on to fruits, vegetables or seeds other than application as a stand-alone film.

Description of the Drawings

1. Flow chart for separation of biomass into its components and biofilm production Detailed Description of the Invention

Description of the components/units/parts composing the invention:

1. Raw Material

2. Crusher/Grinder

3. Storage Tank

4. 1^st tank

5. 2^nd tank

6. 1^st Filter/Centrifuge device

7. 1^st by product

8. Hemicellulose precipitation tank

9. 2^nd Filter/Centrifuge

10. 3^rd tank

11. [Extruder

12. Additive

13. 1^st dryer

14. 2^nd by product

15. Intermediate product

16. Film casting/drawing units

17. 2^nd dryer

18. Water

19. Acid/base compounds

20. Alcohol / Organic acid solution

21. Dried intermediate product

22. Biodegradable film pellets

23. Biodegradable polymer film A large fraction of the structure of the biodegradable films produced according to the present invention is composed of hemicellulose. Additionally, biodegradable films produced according to the present invention also contain lignin (%0.5 - %25) and semiconductor nanocrystalline particles (TiO₂, ZnO₂ etc.). Furthermore the structure of the said film also contains cellulose, pectin, water soluble biomass, clay, zeolite, water, plasticizers known in the literature such as glycerol, phenolics obtained from different types of biomass such as tannic acid, oil and wax either separately or in combination.

The hemicellulose based biodegradable films produced according to the present invention, which are produced from cotton stalk, sunflower stalk, corn cob, stalks and brans of various cereals such as wheat, oat, barley, agricultural wastes such as hazelnut shell or forestry wastes such as saw dust in which the said films are antimicrobial, antifogging and capable of removing undesired gases and where the gas permeability can be adjusted upon variations in the composition, are manufactured according to the production stages described below: In the first stage, the raw material (1), which is a lignocellulosic (composed of cellulose, hemicellulose and lignin) waste composed of agricultural wastes such as cotton stalk, sunflower stalk or husk, corn cob, stalks and brans of various cereals such as wheat, oat, barley, hazelnut shell, etc. or forestry wastes such as saw dust, is processed into smaller pieces within a particle size of lmm - 10 cm in the biomass crusher/grinder. If desired it can be stored in a storage tank (3) in dry phase or processed directly.

After the grinding/size reduction process the biomass is mixed with water (18) in the 1^st tank (4) and kept in the tank for 5 minutes to 2 days at a temperature between 20 - 70 ⁰C.

The suspension formed is transferred into the 2^nd tank (5) (If desired the process can be continued in the 1^st tank (4)) and the volume of water inside is reduced by 5 to 95%. By the addition of acid/base compounds (19) such as potassium hydroxide or sodium hydroxide

(5 - 50%) and NaBH₄ (0.1% - 5%) or another boric compound, the pH of the suspension is brought to between 8 - 14.

The pH of the suspension located in the 2^nd tank is increased to alkaline values since xylan and lignin is soluble in alkaline solution where cellulose is not soluble in the same suspension. Due to this solubility difference cellulose is removed from the suspension.

Suspension is again kept in the tank for 15 minutes to 1 day at a temperature between 20 - 70 ⁰C. Suspension removed from the 2^nd tank (5) is transferred to the 1^st Filter/centrifuge device (6).

After this stage the liquid phase of the suspension is transferred to the hemicellulose precipitation tank (8) while the solid phase is removed from the process as the 1^st by product (7). Removed 1^st by product (7) is cellulose.

In order to accomplish the precipitation process, alcohol/organic acid solution (20) containing 5 - 95% ethanol and 0.5% - 50% acetic acid depending on the desired biofilm properties is pumped in to the hemicellulose precipitation tank (8).

Following the precipitation process the mixture is transferred to the 2^nd filter/centrifuge device (9). Upon the separation of liquid and solid phases the hemicellulose containing solid phase is dissolved in 10 - 90% water in the 3^rd tank (10) and mixed with additives (12) at certain amounts depending on the desired properties of the biodegradable polymer film (22) to be produced. Among these additives cellulose, pectin, lignin, tannic acid or similar plant phenolics, zeolite, clay, glycerol, water, oil, waxes are applied to the mixture by mixing.

Upon these procedures, semi-conductive sol-gel, one of the other additives (12), prepared in advance is added within 0.2 - 30%. Sol-gel is a colloidal suspension that contains silica particles and it gels in order to form a solid structure. The semi-conductive sol-gel solution, which is one of the additives (12), is added to the film forming solution by "in-situ" technique.

If needed, in order to increase the activity of the semiconductor, catalytic metals such as gold, platinum, paladium or non-metals such as sulphur, nitrogen can be added as additives (12) within a final concentration of 0.1 - 10% followed by mixing in the 3^rd tank

(10) for 15 minutes to 5 hours more and kept from 1 hours to 1 day within a temperature of 40 - 150 ⁰C. This mixture, which is the intermediate product (15) that will be used for the production of biodegradable film, can be directly transferred to the film casting/drawing units (16) or it can be transferred the 2^nd dryer (17) and upon drying and storage for as long as desired can be transferred to film casting/drawing units (16) or processed in an extruder

(11) and transformed into biodegradable film pellets (22). The liquid phase separated from the 2^nd filter/centrifuge device (9) is transferred to the 1^st dryer (13) and the 2^nd by product (14), lignin, is obtained.

After the intermediate product (15) is obtained according to the biodegradable polymer film (23) production process described in the present invention the final product, which is the biodegradable polymer film (23), can be produced by three different methods.

1 - The intermediate product (15) obtained from the 3^rd tank (10) in the form of solid granules or liquid mixture is processed into biodegradable polymer film (23) by the techniques known in the prior art and employed in the plastic film producing facilities such as calendaring, casting, solvent casting in the film casting/drawing units (16).

2 - The dried intermediate product (21) obtained from the 2^nd dryer (17) is transferred to the film casting/drawing units (16) such as casting and solution casting units, which are known in the prior art and the main product, which is the biodegradable polymer film (23), is obtained. 3 - Biodegradable film pellets (22) obtained from the extruder (11) are transferred to the film casting/drawing units (16) such as casting and solution casting units, which are known in the prior art and the main product, which is the biodegradable polymer film (23), is obtained.

The biodegradable film pellets (22) and the dried intermediate product (21) can be stored as long as desired until the final process, which is the production of biodegradable polymer films (23) in the film casting/drawing units (16).

Other than being processed in the film casting/drawing units (16) into the main product, which is the biodegradable polymer film (22), the intermediate product (15), which is the solid granules or the liquid mixture, can also be used in the production of disposable biodegradable containers.

The semi-conductive sol-gel prepared in advance, which is one of the additives (12), was added to the hemicellulose containing solid phase in the 3^rd tank (10) that was obtained from the 2^nd filter/centrifuge device (9).

In another application of the present invention, sol-gel, which is one of the additives (12), is not added while the hemicellulose containing solid phase is in the 3^rd tank (10) however other additives (12) are added in order to obtain the desired liquid or solid mixture. Shortly before the production of the film, crystal particles obtained by the calcination of sol- gel, which is one of the additives (12), at a temperature between 400 - 650 ⁰C for 15 minutes to 5 hours can be added onto the intermediate product (15). In another application of the present invention semiconductors (TiO₂, ZnO₂, etc.) can be coated onto the biodegradable polymer film (22) by sol-gel dip coating or spraying methods. In another application of the present invention, other than being used as a film, the intermediate product (15) can also be used as a coating material onto card board, paper and plastic or directly onto fruits, vegetables or seeds. The said coating process is accomplished by dipping/spraying as known in the prior art. Oil and wax can also be applied onto the biodegradable polymeric film (22) by dipping/spraying.

Semiconductive crystal material such as TiO₂, which is one of the semiconductive sol- gel additives (12), is used for the acquisition of antimicrobial characteristics and removal (oxidation) of undesired gases by the biodegradable polymer film (22) described in the present invention.

These crystals do not reduce the biodegradation rate of the biodegradable polymer film (22), in fact the biodegradation rate is increased if the film is exposed to light.

For the photocata lytic activity to take place, day light or indoor lighting is sufficient for the biodegradable polymer films (22) described in the present invention. Material exposed to light for a certain period of time keeps on demonstrating photocatalytic activity for some time even in the dark.

Among the other additives (12), cellulose, pectin and lignin are used to improve the mechanical properties, phenolics (natural anti-microbial compounds obtained from plant wastes) such as tannic acid are used for anti-microbial effect, zeolite, clay and/or vegetable oil or wax are used to modify water vapor permeability and plasticizers such as glycerol, water are used to modify the permeability of gases such as oxygen and ethylene in addition to modifying water vapor permeability.

Claims

1. A biodegradable polymer film (23) production process;

• Comprising crusher/grinder (2), storage tank (3), 1^st tank (4), 2^nd tank (5), 1^st filter/centrifuge device (6), hemicellulose precipitation tank (8), 2^nd filter/centrifuge device (9), 3^rd tank (10), extruder (11), film casting/drawing units (16) and 2^nd dryer (17) as main equipments.

• Using raw material (1), water (18), acid/base compounds (19) and alcohol/organic acid solution (20) as the main process inputs.

2. The biodegradable polymer film (23) production process according to claim 1 wherein the raw material (1) is composed of agricultural wastes such as cotton stalk, sunflower stalk or husk, corn cob, stalks and brans of various cereals such as wheat, oat, barley, hazelnut shell or forestry wastes such as saw dust.

3. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the acid/base compounds (19) added in to the 2nd tank are composed of base such as potassium hydroxide, sodium hydroxide between a concentration of 5% - 50% and NaBH4 or another boric compound between a concentration of 0,1% - 5%.

4. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the alcohol/organic acid solution (20) added into the hemicellulose precipitation tank (8) is composed of 5 - 95% ethanol and 0,5 - 50% organic acid such as acetic acid.

5. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the additives (12) are composed of cellulose, pectin, lignin, tannic acid or similar plant phenolics, zeolite, clay, glycerol, water, oil, wax, sol-gel between a concentration of 0,2% - 30%, salts of catalytic metals such as gold, platinum, paladium and non-metal additives such as sulphur or nitrogen.

6. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the sol-gel, which is one of the additives (12), is composed of semi-conductive nano crystals such as T1O2, ZnO2, etc.

7. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the raw material (1) is crushed into small particles with sizes within 1 mm to 10 cm in the crusher/grinder (2).

8. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biomass obtained from the crusher/grinder (2) is kept in a storage tank (3) in dry phase.

9. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biomass obtained from the crusher/grinder (2) is preferably fed instantly into the 1^st tank (4) without being kept in the storage tank (3).

10. The biodegradable polymer film (22) production process according to anyone of the above claims wherein the biomass obtained from the crusher/grinder (2) is mixed with water (18) in the 1^st tank (4).

11. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biomass mixed with water (18) in the 1^st tank (4) is kept here for 5 minutes to 2 days at a temperature between 20 - 70 ⁰C.

12. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biomass/water suspension formed in the 1^st tank (4) is transferred to the 2^nd tank (5) for further processes.

13. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the volume of water in the biomass/water suspension taken into the 2^nd tank (5) is reduced between 5% to 95%.

14. The biodegradable polymer film (22) production process according to anyone of the above claims wherein the pH of the suspension is increased to alkaline values (between pH 8 and pH 14) by the addition of acid base compounds (19) composed of base such as potassium hydroxide, sodium hydroxide between a concentration of 5% - 50% and NaBH₄ or another boric compound between a concentration of 0,1% - 5%.

15. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the processes that take place in the 2^nd tank (5) can also take place in the 1^st tank (4) if preferred.

16. The biodegradable polymer film (22) production process according to anyone of the above claims wherein the suspension obtained by the addition of acid/base compounds (19) is kept in the 2^nd tank (5) for 15 minutes to 1 day at a temperature between 20 - 70⁰C.

17. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the suspension obtained from the 2^nd tank (5) is transferred to the 1^st filter/centrifuge device (6).

18. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the liquid phase of the suspension transferred to the 1^st filter/centrifuge device (6) is transferred to the hemicellulose precipitation tank (8).

19. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the solid phase of the suspension transferred to the 1^st filter/centrifuge device (6) is removed from the system as the 1^st by-product (7).

20. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the 1^st by-product (7) removed from the system is cellulose.

21. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the alcohol/organic acid solution (20) composed of 5 - 95% ethanol and 5 - 50% organic acid such as acetic acid depending on the desired properties of the biofilm to be produced is pumped into the hemicellulose precipitation tank (8).

22. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the mixture obtained in the hemicellulose precipitation tank (8) is transferred to the 2^nd filter/centrifuge device (9).

23. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the hemicellulose containing solid phase of the mixture transferred to the 2^nd filter/centrifuge device (9) is transferred into the 3^rd tank (10).

24. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the liquid phase of the mixture transferred to the 2^nd filter/centrifuge device (9) is transferred to the 1^st dryer (13).

25. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the liquid phase of the suspension transferred to the 1^st dryer (13) is removed from the system as the 2^nd by-product (14) upon drying.

26. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the 2^nd by-product (14) removed from the system is lignin.

27. The biodegradable polymer film (22) production process according to anyone of the above claims wherein the hemicellulose containing solid phase transferred to the 3^rd tank (10) is dissolved in 10 - 90% water.

28. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the hemicellulose containing solid phase transferred into the 3^rd tank (10) is mixed with additives (12) depending on the desired properties of the biodegradable polymer film (22) to be obtained.

29. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the additives (12) composed of cellulose, pectin, lignin, tannic acid or similar plant phenolics, zeolite, clay, glycerol, oil, wax are applied to the solution in the 3^rd tank (10) by mixing.

30. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the sol-gel prepared in-advance, which is one of the additives (12) is applied to the solution within a concentration of 0,2% to 30%.

31. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the sol-gel prepared in-advance, which is one of the additives (12), is added to the solution by "in-situ" technique.

32. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the salts of catalytic metals such as gold, platinum, paladium or non-metals such as sulphur, nitrogen are added as additives (12) into the solution in the 3^rd tank (10) within a concentration of 0,1% to 10% in order to increase the semiconductor activity.

33. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the solution in the 3^rd tank (10) is kept between 1 hour to one day at a temperature of 40 - 150 ⁰C.

34. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the mixture obtained in the 3^rd tank (10) is the intermediate product (15).

35. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the intermediate product (15) obtained in the 3^rd tank (10) is preferably transferred to the film casting/drawing units (16).

36. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the by-product (15) obtained from the 3^rd tank is preferably transferred to the 2^nd dryer.

37. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the by-product (15) obtained from the 3^rd tank is preferably transferred to the extruder (11).

38. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the by-product (15) transferred to the extruder (11) is processed into biodegradable film pellets (22).

39. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biodegradable polymer film (23) is produced from the by-product (15), which is the raw material in the from of solid particles or liquid, by the techniques known in the prior art such as calendaring, casting or upon solubilizing, in film casting/drawing units (16).

40. The biodegradable polymer film (23) production process according to anyone of the above claims wherein biodegradable polymer film (23) is preferably produced by processing the dried intermediate product (21) obtained from the 2^nd dryer (17) in the film casting/drawing units (16), which are known in the prior art.

41. The biodegradable polymer film (23) production process according to anyone of the above claims wherein biodegradable polymer film (23) is produced by processing biodegradable film pellets (22) obtained from the extruder (11) in the film casting/drawing units (16) such as casting or solution casting, which are known in the prior art.

42. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biodegradable film pellets (22) and the dried intermediate product (21) can be stored as long as desired (without a time limit) until the final process, which is the production of biodegradable polymer films (23) in the film casting/drawing units (16).

43. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the by-product (15), which is the raw material in the form of solid particles or liquid, can also be used in the production of disposable bioplastic containers other than being processed into biodegradable polymer film (23) in film casting/drawing units (16).

44. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the sol-gel, which is one of the additives (12), is not added while the hemicellulose containing solid phase is in the 3^rd tank (10).

45. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the crystal particles, prepared by the calcination of the sol- gel, which is one of the additives (12), at a temperature of 400-650 ⁰C for 15 minutes to 5 hours, are added onto the intermediate product (15).

46. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the semi-conductors (TiO₂, ZnO₂, etc.) can be coated onto the biodegradable polymer film (23) by dipping or spraying methods.

47. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the by-product (15) obtained in the 3^rd tank (10) can also be applied as a coating material onto cardboard, paper, plastic or directly on fruits, vegetables or seeds other being used as a film.

48. The biodegradable polymer film (22) production process according to anyone of the above claims wherein oil and wax can preferably be coated onto the biodegradable polymer film (22) by dipping, spraying.

49. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the biodegradable polymer film (23) produced is antimicrobial, anti-fogging and capable of removing undesired gases.

50. The biodegradable polymer film (23) production process according to anyone of the above claims wherein the gas permeability of the biodegradable polymer film (23) produced can be modified by altering its composition.