阅读说明：本技术 基于纤维素的组合物 (Cellulose-based composition ) 是由 J·卡米宁 M·帕克基宁 L·凯拉 T·沃里宁 H·塞塔拉 K·卡妙维尔塔 L·维克斯特 于 2018-04-23 设计创作，主要内容包括：本发明涉及一种用于制造膜或箔的基于纤维素的组合物以及该组合物的制备方法,其中该组合物包含选自纤维素乙酸丁酸酯、纤维素乙酸丙酸酯和乙基纤维素的至少一种,以及妥尔油脂肪酸酯。本发明还涉及包含该组合物的包装膜和该组合物的用途。(The present invention relates to a cellulose-based composition for manufacturing a film or foil, wherein the composition comprises at least one selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a tall oil fatty acid ester, and a method for preparing the composition. The invention also relates to a packaging film comprising the composition and to the use of the composition.)

1. A cellulose-based composition for the manufacture of a film or foil, characterized in that the composition comprises:

a. at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and

b. the tall oil fatty acid ester is a fatty acid ester,

wherein the at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose has a molar mass of greater than 20,000 Da.

2. A cellulose-based composition according to claim 1, characterized in that the total amount of the at least one polymer is at least 60 wt. -%, preferably at least 70 wt. -%, based on the total weight of the composition.

3. The cellulose-based composition according to claim 1 or 2, characterized in that the composition comprises, based on the total weight of the composition

-10 to 80 wt% of cellulose acetate butyrate,

-10 to 80 wt% of cellulose acetate propionate,

from 0 to 90% by weight, preferably from 10 to 80% by weight, of ethylcellulose, and

5 to 50 wt.%, preferably 10 to 45 wt.% tall oil fatty acid ester.

4. A cellulose-based composition according to any one of the preceding claims, characterized in that it comprises, based on the total weight of the composition:

10 to 90 wt.%, preferably 40 to 80 wt.%, of cellulose acetate butyrate,

0 to 50 wt% of cellulose acetate propionate,

0 to 40 wt% of ethyl cellulose, and

10 to 50 wt% tall oil fatty acid ester.

5. A cellulose-based composition according to any one of the preceding claims, characterized in that the polymer selected from cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose is thermoplastic and water-insoluble.

6. A cellulose-based composition according to any one of the preceding claims, characterized in that the at least one polymer selected from cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose has a molar mass of from 20,000 to 95,000Da, preferably from 20,000 to 90,000Da, more preferably from 30,000 to 70,000 Da.

7. Cellulose-based composition according to any one of the preceding claims, characterized in that it comprises a white pigment, preferably the white pigment is TiO₂。

8. A cellulose-based composition according to any one of the preceding claims, characterized in that the tall oil fatty acid ester is a methyl ester of tall oil fatty acid.

9. A cellulose-based composition according to any one of the preceding claims, characterized in that the composition comprises at least one further softening agent in addition to the tall oil fatty acid ester.

10. A cellulose-based composition according to any one of the preceding claims, characterized in that the composition comprises at least one further polymer, preferably polybutylene succinate (PBS).

11. A packaging film, characterized in that it comprises a cellulose-based composition according to any one of claims 1 to 10.

12. The packaging film according to claim 11, characterized in that it is manufactured using a blown film process.

13. A method for manufacturing a film or foil, characterized in that the method comprises the steps of:

a. melt mixing a composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a tall oil fatty acid ester to obtain a homogeneous mixture, wherein optionally the tall oil fatty acid ester is added to the polymer in at least two steps;

b. granulating the homogeneous mixture to obtain a granulated feedstock; and

c. producing a film or foil material from said particulate feedstock,

wherein at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose has a molar mass greater than 20,000 Da.

14. The method according to claim 12, characterized in that the composition in step a is a cellulose-based composition according to any one of claims 1 to 10.

15. A method according to claim 13 or 14, characterized in that step c comprises producing a film or foil material from the granular raw material by using a blown film method.

16. Use of a cellulose-based composition according to any one of claims 1 to 10 in the manufacture of packaging films.

17. Use according to claim 16, characterized in that it comprises the manufacture of packaging films using a film blowing process.

18. Use of a cellulose based composition according to any one of claims 1 to 10 in a blown film process.

Background

The present invention relates to a cellulose-based composition for the manufacture of a film or foil, its use, a packaging film manufactured therefrom and a process for the manufacture of a film or foil. In particular, the present invention relates to a composition for the manufacture of a film or foil, the composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a Tall Oil Fatty Acid (TOFA) ester, wherein the molar mass of the at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose is greater than 20,000 Da.

Disclosure of Invention

The object of the present invention is to achieve a solution to the above-mentioned problems. In particular, it is an object of the present invention to propose a cellulose-based composition which can be used for the manufacture of films or foils. The new cellulose-based compositions can replace films or foils based on fossil raw materials and be used as packaging or wrapping materials. Thus, the cellulose-based compositions and films or foils made therefrom provide retailers and consumers with a more sustainable packaging material choice.

The object of the invention is achieved by a composition having the features of the independent claims. Preferred embodiments of the invention are set forth in the independent claims. It is therefore an object of the present invention to provide a cellulose-based composition for use in the manufacture of films or foils. The cellulose-based composition according to the invention comprises at least one cellulose-based polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and further comprises a tall oil fatty acid ester, wherein the molar mass of the at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose is greater than 20,000 Da. The invention also relates to a packaging film comprising the cellulose-based composition according to the invention.

In addition to the novel compositions and packaging films, the present invention also relates to a process for the manufacture of a film or foil. The method according to the invention comprises the following steps:

melt mixing a composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose and a tall oil fatty acid ester to obtain a homogeneous mixture (ester to obtain a homogeneous mixture), wherein optionally the tall oil fatty acid ester is added to the polymer in at least two steps;

-granulating the homogeneous mixture to obtain a granulated raw material; and

-producing a film or foil material from the particulate feedstock.

The invention also relates to the use of the cellulose-based composition according to the invention for producing packaging films. The invention also relates to the use of the cellulose-based composition according to the invention in a blown film process.

The present invention is based on the following surprising findings: an environmentally friendly composition for manufacturing a film or foil may be prepared from a mixture comprising at least one cellulose-based polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a tall oil fatty acid ester. The resulting composition may be formed into a packaging film or foil having adhesive properties.

One advantage of the composition according to the invention is that it can be processed in conventional machines which are now used for the manufacture and processing of plastic films. Therefore, expensive equipment investment is not required.

Brief description of the drawings

In the following, the invention is explained in more detail with reference to fig. 1, wherein fig. 1 shows an example of a film made from a composition according to the invention.

Definition of

In the present application and claims, the following terms and expressions have the meanings defined below.

"cellulose-based" is defined as comprising a polymer obtained from fibers derived from a cellulose-containing material. Thus, the polymer obtained from the fiber derived from the cellulose-containing material is a biopolymer. Cellulose-based polymers are generally derivatives, such as ethers or esters of cellulose. The cellulose-containing material may be obtained from various raw materials, such as wood, bark or leaves of plants, or from plant-based materials.

"cellulose acetate butyrate" (CAB) polymers and "cellulose acetate propionate" (CAP) polymers are cellulose derivatives. They are produced by esterification of some of the hydroxyl groups in the cellulose polymer chain on repeating glucose units. Cellulose acetate butyrate/propionate is used as a binder and additive in coating applications for a variety of substrates. These products provide a wide range of properties based on their butyryl/propyl, acetyl and hydroxyl content.

"Ethyl cellulose" (EC) polymers are another derivative of cellulose. Some of the hydroxyl groups in the cellulose polymer chain on the repeating glucose units have been converted to ether groups. Ethylcellulose is mainly used in industrial applications, such as films, but certain grades of products can also be used in regulated markets, such as food and pharmaceuticals. The number of ethyl groups can vary depending on the manufacturing process and impart various properties to the material.

A "tall oil fatty acid ester" or TOFA ester is an ester of a tall oil fatty acid. Typically, tall oil fatty acid methyl esters are used.

"packaging film" may be, for example, cling film, shrink film, stretch film, bag film or container liners, films for consumer packaging (e.g., packaging films for frozen products; shrink films for transport packaging; food wrapping films; packaging bags or form, fill and seal packaging films), laminate films (e.g., aluminum or paper laminate films for packaging, for example, milk or coffee), barrier films (e.g., films used as aroma or oxygen barriers for packaging food products (e.g., chilled meat and cheese), films for packaging medical products, agricultural films (e.g., greenhouse films, crop promoting films (crop forming films), silage films, silage stretch films), or films for cosmetic packaging.

"blown film" or "film blowing" or "blown film extrusion" is one of the most common film manufacturing processes. Blown film processes are sometimes also referred to as tubular film extrusion. The method involves extruding plastic through a circular die and then performing "bubble-like" expansion.

Detailed Description

The present invention relates to a cellulose-based composition for the manufacture of films or foils, which is environmentally friendly in that it can be made from renewable resources. The new composition may be formed into a packaging material or film and it may be used for wrapping and packaging to replace the commonly used fossil plastic materials based on e.g. polyethylene or polypropylene. The novel composition comprises at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a tall oil fatty acid ester, all from renewable resources. The new composition is suitably an environmentally friendly bioplastic material.

The present invention relates to a cellulose-based composition for the manufacture of films or foils, comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose. In addition to one or more of these polymers, the composition also includes a tall oil fatty acid ester. At least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose has a molar mass greater than 20,000 Da.

According to one embodiment of the invention, the cellulose-based composition used for manufacturing the film or foil consists of at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, tall oil fatty acid ester and optionally additives used in the plastic composition, such as softeners, pigments or other additives. At least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose has a molar mass greater than 20,000 Da.

In the cellulose-based composition according to the invention, the total amount of the at least one polymer selected from cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose is at least 40 wt%, preferably at least 50 wt%, more preferably at least 60 wt% or at least 70 wt%, based on the total weight of the composition. According to one embodiment, the total amount of the at least one polymer may be from 40 to 95 wt%, or for example from 50 to 90 wt% or from 60 to 70 wt%, based on the total amount of the composition.

The composition according to the invention may comprise 0 to 90 wt%, preferably 10 to 80 wt%, of cellulose acetate butyrate, and/or 0 to 90 wt%, preferably 10 to 80 wt%, of cellulose acetate propionate, and/or 0 to 90 wt%, preferably 10 to 80 wt%, of ethyl cellulose, and 5 to 50 wt%, preferably 10 to 45 wt%, of tall oil fatty acid ester. Thus, in the composition according to the invention, the amount of tall oil fatty acid ester may be, for example, 5 to 50 wt.%, 10 to 45 wt.%, 15 to 35 wt.%, 20 to 30 wt.% or 30 to 40 wt.%, based on the total weight of the composition.

According to one embodiment of the invention, the cellulose-based composition comprises 10 to 90 wt. -%, preferably 40 to 80 wt. -% of cellulose acetate butyrate, 0 to 50 wt. -% of cellulose acetate propionate, 0 to 40 wt. -% of ethyl cellulose and 10 to 50 wt. -% of tall oil fatty acid ester, based on the total weight of the composition. The composition according to the invention may for example comprise 50 to 75 wt%, or 60 to 70 wt% of cellulose acetate butyrate, based on the total weight of the composition.

Suitably, the at least one polymer selected from cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose has a molar mass of greater than 20,000 Da. Suitably, at least one polymer selected from the group has a molar mass of from 20,000 to 95,000Da, preferably from 20,000 to 90,000Da, for example from 30,000 to 70,000 Da. If the molar mass of all components is too low, there is a risk that the composition is not suitable for blown film processing, since the material is not strong or elastic enough for blown film processing. Thus, the specified molar mass value enables the use of the polymer in blown film applications. Blown film processing enables the formation of films or foils, preferably with adhesive properties, suitable for use as packaging materials.

Different grades of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose are available from several suppliers. In the composition according to the invention, the mixture of polymer raw materials influences the properties of the formed film or foil. In other words, in the case of a mixture of several polymers, it is necessary to evaluate the combined properties of the polymers when forming the composition according to the invention. For example, if one polymer has a high molar mass, for example 90,000Da or 70,000Da, it may be suitable to combine that polymer with another polymer having a lower molar mass. Alternatively or additionally, for polymers with a high molar mass, higher amounts of softeners are required. The measurement of molar mass can be carried out by Size Exclusion Chromatography (SEC), which is used in the tests related to the present invention (see example 2). Suitable SEC measurement conditions are Styragel HR 4 with a pre-column and 3 columns in chloroform eluent (0.6ml/min, T ═ 30 ℃). The elution profile can be detected using a Waters 2414 refractive index detector. The Molar Mass Distribution (MMD) can be calculated from the 10 XPS (580-3040000g/mol) standard using Waters Empower 3 software. In example 2, PS was used as a standard. In the comparative experiments, the PS standard gave results slightly higher than the molar mass value provided by the manufacturer (example 1). Thus, if the CAP criterion is available in example 2, the molar mass value of example 2 will be slightly lower. Thus, according to one embodiment, the elution profile is detected using a Waters 2414 refractive index detector using Styragel HR 4 and 3 columns with pre-columns in chloroform eluate (0.6ml/min, T ═ 30 ℃) and the Molar Mass Distribution (MMD) is calculated according to the 10x PS (580-3040000g/mol) standard using Waters Empower 3 software, the molar mass of at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose being between 25,000 and 95,000Da as measured by Size Exclusion Chromatography (SEC).

The cellulose acetate butyrate, cellulose acetate propionate and/or ethylcellulose polymer of the composition according to the invention is suitably a thermoplastic polymer. In order to be suitable for use in packaging films, the cellulose-based polymer used in the composition of the present invention should not be water soluble. Thus, polymers selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose are suitably insoluble in water. In addition, the polymer needs to be suitable for use with tall oil fatty acid ester softeners. It has been found that cellulose acetate butyrate, cellulose acetate propionate and/or ethylcellulose polymers of the composition according to the invention meet these requirements. Furthermore, they are suitable for use in compositions which can be used to produce films or foils having adhesive properties. Thus, in one aspect, the polymer used in the composition of the invention is a cellulose-based polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, wherein the polymer is thermoplastic and water insoluble. Other cellulose-based polymers may be present, which have similar properties to cellulose acetate butyrate, cellulose acetate propionate or ethyl cellulose, and are also suitable for use in the compositions according to the invention. Thus, the composition according to the invention may also comprise other cellulose-based polymers.

According to one embodiment, the cellulose-based composition of the present invention comprises at least two polymers selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a tall oil fatty acid ester. According to one embodiment, the cellulose-based composition of the present invention comprises cellulose acetate butyrate and tall oil fatty acid methyl ester.

The cellulose-based composition according to the invention also comprises a tall oil fatty acid ester. Tall oil fatty acid esters are used as softeners or plasticizers in the compositions of the present invention. The advantage of tall oil fatty acid is that it is a wood based composition, i.e. it is made from renewable resources. Another advantage for certain applications of the packaging film according to the present invention is that food grade TOFA esters are commercially available. For example if used for packaging foodstuffs. According to one embodiment of the present invention, the tall oil fatty acid ester is a tall oil fatty acid methyl ester. Tall oil fatty acid methyl ester is commercially available and is therefore an advantageous alternative as it does not require separate preparation.

In addition to the tall oil fatty acid ester, the cellulose-based composition according to the invention may also comprise at least one further softening agent.

According to one embodiment, the cellulose-based composition according to the invention comprises, in addition to said at least one polymer chosen from cellulose acetate butyrate, cellulose acetate propionate and ethylcellulose, at least one other polymer, preferably polybutylene succinate. Polybutylene succinate (PBS) is suitably mixed with the cellulose-based polymer. Other possible polymers suitable for blending with the cellulose-based polymer are polypropylene glycol succinate (PPS), poly (butylene succinate-co-adipate) (PBSA), polyhydroxybutyrate, polyhexamethylene glutarate, polyhexamethylene adipate, polyethylene glycol succinate, polybutylene glutarate, polybutylene adipate, polyethylene glycol glutarate, polyethylene glycol adipate, polyethylene glycol succinate, or polyethylene glycol succinate.

According to one embodiment, the total amount of all polymers in the composition of the invention is from 60 to 95 wt%, based on the total weight of the composition.

Furthermore, the composition of the present invention may comprise a pigment. The pigment is preferably a white pigment. The white pigment may be, for example, titanium dioxide (TiO)₂). The addition of a white pigment to the composition makes the formed film or foil material white and translucent. This is particularly advantageous when the packaging film according to the invention is used for packaging food products, since white color is usedMaking the food product inside the package appear more appealing to the consumer. In the absence of white pigments, the film or foil material produced from the composition according to the invention may have a yellowish colour. Thus, the white pigment has the effect of masking the natural color of the film or foil, which would otherwise make the food less attractive to the consumer.

In addition to pigments, the compositions according to the invention may also comprise further components, for example additives which are customarily used in plastics. These additives are, for example, fillers, auxiliaries or other agents. Typically, the amount of these additives varies from 0.01 to 10 wt% based on the weight of the composition. The amount of an additive may be, for example, from 0.1 to 5 wt%, based on the weight of the composition.

One aspect of the invention is a cellulose-based composition for the manufacture of films or foils, which does not comprise any fossil raw material based components. In other words, in such a case, the composition may consist essentially or entirely of renewable raw materials.

The invention also relates to a packaging film comprising the cellulose-based composition according to the invention. The packaging film according to the present invention can be manufactured using a film blowing method (blown film extrusion).

According to one embodiment, the composition for manufacturing a film or foil according to the present invention may be processed into a film using blown film extrusion (blown film process) or cast film extrusion (cast film extrusion).

According to one embodiment, the cellulose-based composition is biodegradable. The new packaging films or foils made from cellulose-based compositions may also be biodegradable.

The cellulose-based composition can also be mixed with conventional plastic raw materials, such as polyethylene or polypropylene. In this way, a composition suitable for the manufacture of film or foil materials with certain advantageous properties is obtained. The choice of raw blend depends on the requirements for the film or foil material and its end use.

According to one embodiment of the present invention, the cellulose-based composition used to make the film or foil is formed into a cling film that can be used to replace conventional cling films made of, for example, LDPE. The preservative film can be made of food-grade raw materials. Therefore, the preservative film can be used for packaging or wrapping food.

The invention also relates to a method for manufacturing a film or foil. The method for manufacturing a film or foil according to the invention comprises the steps of:

a. melt mixing a composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose, and a tall oil fatty acid ester to obtain a homogeneous mixture, wherein optionally the tall oil fatty acid ester is added to the polymer in at least two steps;

b. granulating the homogeneous mixture to obtain a granulated raw material; and

c. producing a film or foil material from said particulate feedstock,

according to one embodiment, the composition in step a is a cellulose-based composition according to the invention as described above.

According to one embodiment, step c of the method according to the invention comprises producing a film or foil material from the particulate starting material by using a film blowing process.

Preferably, in the melt mixing step of the process, the tall oil fatty acid ester is added gradually and/or in two steps to a composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose. The inventors of the present invention have found that in this way the melt mixing step can be made more efficient. Otherwise, it may be difficult to obtain a homogeneous mixture. According to one embodiment, the tall oil fatty acid ester is added to the composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose by multiple steps, for example at least three separate steps, or at least four separate steps.

Melt mixing may be performed as a continuous compounding process. Melt mixing is suitably carried out using a two-screw compounder. When a blender is used, the tall oil fatty acid ester may be added from several stages or points to a composition comprising at least one polymer selected from the group consisting of cellulose acetate butyrate, cellulose acetate propionate and ethyl cellulose.

Melt mixing may also be carried out in a batch mixer.

Optionally, the method may comprise a pre-mixing or impregnation step of some of the components of the mixture to be formed in step a.

Standard tests known to the person skilled in the art can be carried out to ensure that the mixture obtained in step a is suitable for blown film processing. The compositions of the present invention need to meet these requirements.

The compositions of the present invention can be processed in conventional equipment used in blown film processing. The requirements of the starting materials and the adjustment of other parameters are known to the person skilled in the art.

The properties, such as thickness, density, etc., of the film or foil or packaging material made from the composition of the present invention need to be adjusted to suit its intended use or application.

In addition, standard tests exist to ensure that the plastic wrap or packaging film is effective. Some important tests are for example permeability (water vapour and gas), impact resistance, water absorption and tear strength. The formed packaging film or foil needs to meet certain specific requirements, depending on the intended application, e.g. for packaging food products.

The invention also relates to the use of the cellulose-based composition according to the invention for producing packaging films. Preferably, the use comprises the manufacture of packaging film using a blown film process.

Furthermore, the present invention relates to the use of the cellulose-based composition according to the invention in a blown film process.

The novel composition according to the invention may comprise essentially only raw materials from renewable sources. The novel composition may consist entirely of renewable sources. The novel composition may also consist entirely of biodegradable raw materials from renewable sources. The composition according to the invention is suitable for blown film processing.

LDPE cling film commonly used for packaging has a number of problems. One problem is that typically only a few percent of the LDPE is recovered. In fact, flexible plastic packaging materials are generally not accepted at all by recycling programs. Therefore, the introduction of environmentally friendly alternatives to plastic wrap materials, such as packaging materials that can be achieved with the composition according to the invention, is a real advantage to achieve sustainable development goals. Suitably, the cellulose-based composition according to the invention also provides a high quality film material to replace the commonly used preservative films.

An important advantage of the composition according to the invention is that the films or foils made therefrom can be manufactured using existing manufacturing processes and techniques. This is therefore an economically viable alternative, as no major investments in new manufacturing equipment are required.

A further advantage associated with packaging materials made from the composition according to the invention is the reduction of plastic waste, since the composition is degradable. Furthermore, since the composition according to the invention can be made from 100% renewable resources, the use of fossil raw materials can be reduced. Furthermore, since the composition according to the invention consists of wood, the production does not take up arable land.

The invention is further illustrated by the following examples.

Example 1

The cellulose-based composition according to the present invention is formed into a plastic film by using a blown film method.

See table 1 for details on the composition and film.

TABLE 1 films made from cellulose-based compositions according to the invention

Film numbering	CAB(70kDa)wt％	CAB(30kDa)wt％	TOFA ester (methyl ester) wt%	Processing temperature (. degree.C.)
					1	0	70	30	140–170
2	60	0	40	170

In table 1, CAB is cellulose acetate butyrate and TOFA ester is tall oil fatty acid methyl ester.

Molar mass (kDa) values are based on information provided by the manufacturer.

The membranes were tested for water absorption by immersing the membrane samples in water for several days. No visible appearance or texture change in the film was observed after immersion in water.

The membranes 1-2 are transparent and have adhesive properties, as can be seen from fig. 1, where one membrane is wrapped around and adhered to a ceramic coffee cup. Therefore, the film is suitable for use as a packaging film such as a plastic wrapping material.