Method for preparing a thermoplastic composition

Abstract

A method for preparing a thermoplastic composition comprising grafted cellulose and / or hemicellulose is disclosed, which may include reacting a cyclic ester monomer with cellulose and / or hemicellulose, thereby at least partially grafting the cellulose and / or hemicellulose with the cyclic ester monomer, thereby forming the thermoplastic composition.

Description

[Technical field]

[0001] The present disclosure relates to methods of preparing thermoplastic compositions, thermoplastic compositions, and products obtainable therefrom. [Background technology]

[0002] Cellulose and hemicellulose are renewable raw materials well suited for the production of thermoplastic materials.

[0003] Thermoplastic cellulose derivatives, which can be processed using conventionally used thermoplastic processing equipment such as extrusion and molding, are of great interest as replacements for fossil-based thermoplastic materials. Furthermore, based on general considerations regarding the correlation between molecular structure, degree of substitution and biodegradability, cellulose derivatives may enable both thermoplastic processing and management of post-consumer waste via biological degradation.

[0004] However, balancing biodegradability, thermoplasticity and material properties can be difficult. Summary of the Invention

[0005] A method for preparing a thermoplastic composition comprising grafted cellulose and / or hemicellulose is disclosed, which may include reacting a cyclic ester monomer with cellulose and / or hemicellulose, thereby at least partially grafting the cellulose and / or hemicellulose with the cyclic ester monomer, thereby forming the thermoplastic composition.

[0006] The accompanying drawings, which are included to provide a further understanding of the embodiments and are incorporated in and constitute a part of this specification, illustrate various embodiments. [Brief description of the drawings]

[0007] [Figure 1]FIG. 1 illustrates one embodiment of a method for preparing a thermoplastic composition comprising grafted cellulose and / or hemicellulose. [Diagram 2] 1 is a graph showing Fourier transform infrared spectroscopy (FTIR) spectra of the cellulose starting material and the resulting caprolactone-grafted cellulose. [Diagram 3] 1 is a graph showing the biodegradability of lactone grafted cellulose samples with different degrees of substitution. Ref. = Reference, MCC = Microcrystalline Cellulose, 20-02831-007 = Grafted cellulose with a degree of substitution of 1.72 (Example 2) and 20-02831-012 = Grafted cellulose with a degree of substitution of 0.61 (Example 1). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A method for preparing a thermoplastic composition comprising grafted cellulose and / or hemicellulose is disclosed, which may include reacting a cyclic ester monomer with cellulose and / or hemicellulose, thereby at least partially grafting the cellulose and / or hemicellulose with the cyclic ester monomer, thereby forming the thermoplastic composition.

[0009] The reaction of cyclic ester monomers with cellulose and / or hemicellulose produces fibers containing cellulose and / or hemicellulose grafted with cyclic ester (such as polylactone) monomers, oligomers and / or polymers. The cyclic esters are bonded to the OH groups of the cellulose and / or hemicellulose by ester bonds. Thus, the cyclic esters esterify the cellulose and / or hemicellulose. This reaction can be considered as a ring-opening polymerization reaction of the cyclic ester monomers.

[0010] Thus, the grafted cellulose and / or grafted hemicellulose are the polymerization products of cellulose and / or hemicellulose with cyclic ester monomers.

[0011] However, the cellulose and / or hemicellulose may be at least partially grafted with the cyclic ester monomer, in the sense that at least a portion of the cellulose and / or hemicellulose molecules, fibers and / or fiber bundles, and / or at least a portion of the OH groups of the cellulose and / or hemicellulose molecules may be grafted. The resulting thermoplastic composition may be a composite type product, i.e. a composite.

[0012] Polyesters (such as polylactones), i.e., polyesters that are not grafted to cellulose or hemicellulose, may be obtained as by-products. The polyesters may be at least partially removed if desired, for example if a particular purity level of the thermoplastic composition is desired. The free acid content of the thermoplastic composition may be, for example, less than 2% (w / w), as determined by ASTM standard D871-96. The polyesters, such as polylactones, may be at least partially removed after the reaction, for example by extraction with acetic acid. However, in at least some embodiments, a certain amount of polyester may remain in the thermoplastic composition. This may also have a role in the material properties, such as the melting temperature, of the thermoplastic composition.

[0013] An example of a grafting reaction with ε-caprolactone as the cyclic ester monomer (lactone) is shown in Scheme 1 below. [ka]

[0014] Scheme 1. Reaction mechanism of a) ε-caprolactone grafting of cellulose and b) acid-catalyzed ring-opening polymerization with ε-caprolactone in the modification of cellulose surface.

[0015] The resulting thermoplastic composition may be biodegradable.

[0016] In general, the biodegradation and biodegradability of a polymeric material or composition may depend on the environmental conditions and the time required for degradation. For example, the environmental conditions may be aggressive or less aggressive. The following environmental conditions may be considered in order of increasing aggressiveness: marine environment, fresh water, wastewater treatment plant, soil, home compost, and industrial compost. Biodegradability does not necessarily mean that a product, such as a thermoplastic composition, is biodegradable in any one of these conditions or in any one of these conditions within any given time. For example, less aggressive conditions may require significantly longer periods of time for biodegradation.

[0017] The thermoplastic composition may be biodegradable as determined by OECD Standard 301 F for the testing of chemicals.

[0018] The term "biodegradable", at least in some embodiments, can refer to readily biodegradable as determined by OECD Standard 301 F for the Testing of Chemical Substances (Manometer Breath Test). A readily biodegradable thermoplastic composition or thermoplastic polymeric material can be a thermoplastic composition or thermoplastic polymeric material that reaches at least 60% biodegradability within 28 days as determined by OECD Standard 301 F for the Testing of Chemical Substances.

[0019] It may be possible to adjust and / or control the extent to which cellulose and / or hemicellulose are grafted. For example, if the cellulose and / or hemicellulose are mainly or only surface grafted (e.g., if the fiber bundles containing cellulose and / or hemicellulose are mainly or only surface grafted), the resulting thermoplastic composition may be more economical to manufacture and / or more easily recyclable. If the cellulose and / or hemicellulose are essentially grafted throughout, it may be more difficult to recycle.

[0020] The extent to which the cellulose and / or hemicellulose is grafted may also affect the barrier properties: if the cellulose and / or hemicellulose is essentially grafted throughout, it may have better barrier properties than, for example, thermoplastic cellulose and / or hemicellulose in which the cellulose and / or hemicellulose is primarily or only surface grafted.

[0021] Thus, the degree and / or type of grafting can be adjusted and / or controlled depending on the intended purpose, the environmental impact, the energy efficiency of the material and / or other factors, e.g., the use of toxic solvents can be minimized, the number of processing steps can be minimized, atomic economy can be maximized, and / or waste can be minimized.

[0022] In the context of this specification, the term "a cyclic ester monomer" or "the cyclic ester monomer" may be understood to refer to one or more cyclic ester monomers, and / or mixtures or combinations thereof.

[0023] The cyclic ester monomer may be a lactone or a mixture of one or more lactones.

[0024] The lactone may be represented by the formula (I) and / or (II) [ka] [ka] (In the formula, R 1 and R 2 are each independently selected from the group consisting of H, methyl, ethyl, and propyl; R 3 and R 4are each independently selected from the group consisting of H, methyl, ethyl, and propyl; A is selected from O and N; R 5 is selected from the group consisting of H, methyl, ethyl and propyl when A is N; R 5 is non-existent if A is O, m is an integer ranging from 1 to 5. The lactone may be selected from lactones represented by

[0025] In one embodiment, in Formula I and / or II, R 1 and R 2 One of them is H and the other is R 1 and R 2 the other is selected from the group consisting of H, methyl, ethyl and propyl; R 3 and R 4 One of them is H and the other is R 3 and R 4 the other is selected from the group consisting of H, methyl, ethyl, and propyl; A is selected from O or N; R 5 is selected from the group consisting of H, methyl, ethyl and propyl when A is N; R 5 is non-existent if A is O, m is an integer ranging from 1 to 5.

[0026] In one embodiment, in Formula I and / or II, R 1 and R 2 One of them is H and the other is R 1 and R 2 the other is selected from the group consisting of H, methyl, ethyl and propyl; R 3 and R 4 One of them is H and the other is R 3 and R 4 the other is selected from the group consisting of H, methyl, ethyl, and propyl; A is selected from O or N; R 5is H if A is N, and R 5 is non-existent if A is O, m is an integer ranging from 1 to 5.

[0027] m can be 1, 2, 3, 4 or 5.

[0028] The cyclic ester monomer may be ε-caprolactone, γ-valerolactone, δ-valerolactone, or any mixture or combination thereof.

[0029] In the context of this specification, the term "cellulose and / or hemicellulose" may be understood to refer to cellulose, hemicellulose, or cellulose and hemicellulose.

[0030] The cyclic ester monomer can be reacted with a mixture containing cellulose and hemicellulose. In other words, the cellulose and / or hemicellulose can be provided as a mixture containing cellulose and hemicellulose. Thus, any reference to cellulose and / or hemicellulose in this specification can also be understood to refer to a mixture containing cellulose and hemicellulose. Such a mixture can, for example, include or be a pulp. The pulp can, for example, include or be a wood pulp (e.g., hardwood and / or softwood pulp), a non-wood pulp, and / or an agropulp. The pulp can be a chemical pulp, such as a kraft pulp. The pulp can be a never-dried pulp, for example a never-dried kraft pulp.

[0031] Many cellulose sources may further contain a certain amount of hemicellulose. For example, pulp may contain a mixture of cellulose and hemicellulose. The mixture may contain, for example, at least 3% by weight, or at least 5% by weight, or at least 10% by weight of hemicellulose, based on the total dry weight of cellulose and hemicellulose.

[0032] Cellulose is a polysaccharide containing linear chains of several thousand to ten thousand linked D-glucose units.

[0033] Hemicellulose is a heteropolymer, i.e., the term "hemicellulose" may be understood to refer to several heteropolymers (matrix polysaccharides), such as arabinoxylan. Hemicellulose is present in the cell walls of almost all land plants, together with cellulose. While cellulose is crystalline, strong, and resistant to hydrolysis, hemicellulose has a random amorphous structure and has little strength. In other words, the term "hemicellulose" may be understood to refer to one or more hemicellulose molecules and mixtures thereof. Hemicellulose is composed of a variety of sugars and may include xylose, arabinose, glucose, mannose, galactose, and / or rhamnose. Hemicellulose may contain primarily D-pentose sugars, and occasionally small amounts of L-sugars. Xylose is the sugar monomer most often present in the greatest amount, although in conifers, mannose may be the most abundant sugar. In hemicellulose, not only regular sugars but also their acidified forms, such as glucuronic acid and galacturonic acid, can be found.

[0034] Cellulose can be present as cellulose fibers, macrofibrils and / or microfibrils.

[0035] The cellulose and / or hemicellulose, or mixtures thereof, can be pretreated by thermal, mechanical, physical and / or chemical means, for example by drying, refining, milling, fluffing and / or mercerization.

[0036] Such pretreatment can, for example, open the fiber structure of cellulose and / or hemicellulose, thus increasing the surface area of ​​cellulose and / or hemicellulose, thereby exposing them to grafting. Thus, pretreatment can not only improve the accessibility of OH groups to chemical reactions, but also loosen the fiber structure, where cyclic ester monomers can have better access within the fiber structure. However, in one embodiment, the pretreatment is such that it does not completely separate the cellulose chains from each other. The fiber structure of cellulose present in cellulose and / or hemicellulose can be at least partially preserved after pretreatment.

[0037] The cellulose and / or hemicellulose, or a mixture thereof, may be in the form of, for example, a slurry.

[0038] The cellulose and / or hemicellulose, or mixtures thereof, may be mercerized prior to reaction with the cyclic ester monomer.

[0039] The cellulose and / or hemicellulose, or mixtures thereof, may be mercerized, dried and powdered prior to reaction with the cyclic ester monomer.

[0040] Mercerization can affect the crystalline structure of cellulose. For example, amorphous cellulose chains can align to become cellulose chains with alternating directions. Mercerization can be performed by treating cellulose and / or hemicellulose with a strong base, such as NaOH solution or other alkaline solution, for example, a solution containing 5-50% by weight, or 7-45% by weight, or 10-30% by weight, or about 20% by weight NaOH. After mercerization, the NaOH or other alkaline solution may be at least partially removed and / or the consistency of the pretreated cellulose and / or hemicellulose may be increased.

[0041] The cellulose and / or hemicellulose, or mixtures thereof, when reacted with the cyclic ester monomer, may be dried and powdered cellulose and / or hemicellulose, such as dried and powdered chemical pulp. Such dried and powdered cellulose and / or hemicellulose, or mixtures, may have increased reactivity with the cyclic ester monomer.

[0042] The cyclic ester monomers can be reacted with cellulose and / or hemicellulose, or mixtures thereof, in the presence of an acidic or basic catalyst.

[0043] The cyclic ester monomers can be reacted with cellulose and / or hemicellulose, or mixtures thereof, in the presence of a basic catalyst. Such a basic catalyst can be or include, for example, a strong base such as LiOH, NaOH, KOH, Ca(OH)2, RbOH, Sr(OH)2, CsOH, Ba(OH)2, or any mixture or combination thereof, a superbase catalyst such as ethoxide ion (C2H5ONa), sodium amide (NaNH2), sodium hydride (NaH), CH5N3 (guanidine), or any mixture or combination thereof, or any mixture or combination thereof.

[0044] In embodiments where the cellulose and / or hemicellulose, or mixtures thereof, are mercerized prior to reaction with the cyclic ester monomer, the mercerization solution, e.g., NaOH solution, may act as a basic catalyst. A portion of the mercerization solution may be removed prior to reaction with the cyclic ester monomer.

[0045] The acid catalyst may include or be an organic acid such as citric acid, tartaric acid, acetic acid, and / or any mixture or combination thereof. The acid catalyst may include or be citric acid.

[0046] The cyclic ester monomers can be reacted with the cellulose and / or hemicellulose, or mixtures thereof, at a temperature in the range of about 50-210°C, or in the range of about 100-160°C, or in the range of 110-140°C.

[0047] The cyclic ester monomers can be reacted with the cellulose and / or hemicellulose, or mixtures thereof, for at least 5 minutes, at least 1 hour, or at least 5 hours, or from about 1 to 5 hours.

[0048] In one embodiment, no additional solvent is included or added to the cyclic ester monomer and the cellulose and / or hemicellulose, or mixtures thereof, when they are reacted together.

[0049] The thermoplastic composition may be further processed. The method may further include, for example, washing the thermoplastic composition. The method may further include, for example, removing unreacted cyclic ester monomer.

[0050] The method may further include pelletizing the thermoplastic composition (i.e., forming pellets), or forming a powder, film, filament, melt, and / or 3D shape of the thermoplastic composition. Such products may be formed, for example, by extrusion, extrusion molding, and / or injection molding. In principle, the thermoplastic composition and the thermoplastic polymeric material may be further processed as other thermoplastic materials.

[0051] Also disclosed is a thermoplastic composition comprising grafted cellulose and / or hemicellulose. The cellulose and / or hemicellulose may be cellulose and / or hemicellulose grafted with polyester. The grafted polyester chains may be formed, for example, from at least 10 cyclic ester monomers. In other words, the grafted polyester chains may, for example, each contain at least 10 ester groups. In an embodiment in which the cellulose and / or hemicellulose are grafted with polylactone, the grafted polylactone chains may, for example, be formed from at least 10 lactone monomers.

[0052] The thermoplastic composition may be obtained by a method according to one or more embodiments described herein.

[0053] Any of the embodiments and features described above or below may also be understood to relate to the methods, thermoplastic compositions, thermoplastic polymeric materials, and / or articles according to one or more embodiments described herein.

[0054] The thermoplastic composition can be biodegradable.

[0055] The degree of substitution of the thermoplastic composition and / or the grafted cellulose and / or hemicellulose may be in the range of 0.05 to 2.5. Additionally or alternatively, it may be in the range of 0.1 to 2 or 0.5 to 1.5.

[0056] The melting temperature (T m ) may be in the range of 40 to 230°C.

[0057] The lactone content of the thermoplastic composition may be in the range of 0.1 to 1000, or 0.1 to 200, or 0.5 to 200 (wt % pulp). In this context, the term "lactone content" may be understood to refer to the (relative) amount in the thermoplastic composition of units derived from lactone.

[0058] The lactone content of the thermoplastic composition may be measured as the total lactone content of the thermoplastic composition. The lactone content may include only lactones grafted to cellulose and optionally hemicellulose (polylactones). In some embodiments, it may include the polymerization product of lactones alone (polylactones) that are not grafted to cellulose and optionally hemicellulose. The ungrafted polylactones may be at least partially removed from the thermoplastic composition before measuring the lactone content.

[0059] The whiteness of the thermoplastic composition can be very good. The whiteness of the thermoplastic composition can be similar to that of pulp.

[0060] The thermoplastic compositions, thermoplastic polymeric materials, and / or articles may be recyclable, for example, they may be recyclable in paper and cardboard recycling systems and / or other recycling systems.

[0061] Also disclosed is a thermoplastic polymer material comprising or formed from a thermoplastic composition according to one or more embodiments described herein. The thermoplastic polymer material may optionally further comprise a biocomposite, a second thermoplastic material, a plastic and / or an additive.

[0062] Disclosed are articles obtainable from or formed from thermoplastic compositions according to one or more embodiments described herein and / or thermoplastic polymer materials according to one or more embodiments described herein.

[0063] The article may be, for example, a pellet, powder, film, filament, melt, 3D shape, coating, hot melt adhesive, container, casing, packaging article, film label, paper, medical device, plastic or composite profile, and / or 3D printing filament.

[0064] The thermoplastic polymeric materials and / or articles may be biodegradable. EXAMPLES

[0065] Reference will now be made in detail to various embodiments, examples of which are illustrated in the accompanying drawings.

[0066] The following description discloses some embodiments based on the present disclosure in detail so that those skilled in the art can utilize those embodiments. Not all steps or features of the embodiments are described in detail because many of the steps or features will be apparent to those skilled in the art based on the present specification.

[0067] For brevity, item numbers are maintained in the following exemplary embodiment where elements are repeated.

[0068] FIG. 1 shows an exemplary embodiment of this method. In 1, a composition containing cellulose and hemicellulose, in this case never-dried kraft pulp (cellulose I), is mercerized with a 20 wt. % NaOH solution. Those skilled in the art will understand that various other compositions, such as various other types of pulp or other compositions containing cellulose and / or hemicellulose, can be used instead. In 2, the mercerized pulp is pressed in a filter press, such as a Larox filter press, to at least partially remove the NaOH solution as filtrate and increase the consistency of the pulp. It may be beneficial to reduce the amount of NaOH in the pulp. For example, if the NaOH concentration in the pulp is too high, the pulp may be degraded during the subsequent heating step. At this time, the cellulose in the mercerized pulp is mainly in the form of cellulose II, whereas before mercerization, the cellulose in the pulp is in the form of cellulose I. In this embodiment, the pulp is pretreated, i.e., activated by mercerization, although any other pretreatment described herein may be applied additionally or alternatively. The filtrate that can be obtained from 2 may be reused to minimize reagent costs and prevent waste. In 3, the activated pulp obtained from the mercerization is dried and ground. This can be done, for example, in an H / C (hot / cold) mixer. The H / C mixer is a device with mixing elements. The mixing elements can provide high mixing speeds that can cause friction between the fibers. This friction generates heat even above the boiling point of water. In this way, the pulp can be dried, mixed and refined. The run parameters can be set to define which dryness level is obtained and also how much of the fibers are cut into smaller fiber fractions. It can also be used to mix and separate fiber bundles within certain limits. However, other devices can be used to dry and / or grind the activated pulp, such as other similar devices.

[0069] The dried ground pulp is then grafted at 4 by reacting with ε-caprolactone in the presence of a suitable catalyst, such as any of the basic or acidic catalysts described herein. The cyclic ester monomer in this example is ε-caprolactone, although any of the other cyclic ester monomers described herein can of course be used. Thus, the lactone reacts with the cellulose and hemicellulose of the pulp, thereby grafting the cellulose and hemicellulose, resulting in a thermoplastic composition, i.e., thermoplastic cellulose, at 5.

[0070] Example 1 140 g of ε-caprolactone and 24 g of citric acid as catalyst were added to the Juccheim reactor, and mixing was set to about 8 Hz. The mixture was refluxed at 120° C. for 30 minutes to dissolve the citric acid. The reactor was then cooled to 70° C., and 10 g of birch pulp dried in a hot and cold mixer was added to the reactor. The temperature of the batch reactor was increased to 120° C., mixing was set to 11 Hz, and the reaction started. The reactor was held at this temperature for 5 hours and then worked up as follows: The reactor was first cooled at 40° C., and after cooling, the citric acid catalyst was neutralized using 30 g of 20 wt.% NaOH. The non-immobilized polycaprolactone and citric acid were then extracted from the sample using 300 g of acetic acid at 65° C. for about 60 minutes. The product was then filtered from the liquid, slurried with 2 liters of deionized water, and the procedure repeated until washing yielded a neutral pH suspension. The water was removed as much as possible by filtration and then removed in an oven at 105°C. Differential scanning calorimetry (DSC) results for the product are shown in Table 1. The FTIR spectrum of the product is shown in Figure 2. [Table 1]

[0071] Example 2 500g of ε-caprolactone and 100g of catalytic citric acid were added to a 3L high consistency batch reactor and the mixing was set at about 40 RPM. The mixture was refluxed at 120°C for 30 minutes. The reactor was then cooled to 70°C and 100g of birch pulp dried in a hot and cold mixer was added to the reactor.

[0072] The temperature of the batch reactor is raised to 120° C. and the reaction begins. The reactor is held at this temperature for 3 hours and then worked up as follows.

[0073] The reactor is first cooled at 60°C, and after cooling, 120g of 20wt% NaOH is used to neutralize the citric acid catalyst. The non-immobilized polycaprolactone and citric acid are then extracted from the sample using 1.2kg of acetic acid at 65°C for approximately 60 minutes. The product is then filtered from the liquid, slurried with 2l of deionized water, and the procedure is repeated until a neutral pH suspension is obtained by washing. The water is removed as much as possible by filtration and then removed in a 40°C oven.

[0074] Example 3 Caprolactone grafting was carried out by reacting caprolactone with birch pulp on a laboratory scale using different reactors and catalysts as shown in Table 2. The resulting thermoplastic compositions were found to have different degrees of substitution and different melting temperatures.

[0075] The lactone grafted cellulose compositions were moldable by extrusion and injection molding, for example, they could be melt processed.

[0076] Example 4 - Biodegradability of lactone-grafted cellulose Caprolactone-grafted cellulose composition samples prepared as above with different degrees of substitution (Example 2 (20-02831-007) with DS of 1.72 and Example 1 (20-02831-012) with DS of 0.61) were tested for biodegradability using OECD Standard 301 F for the Testing of Chemical Substances (Manometer Breath Test). The references used were microcrystalline cellulose (MCC) and CH3COONa.

[0077] The results are shown in Figure 3. The lactone grafted cellulose composition samples were at least 60% biodegradable within 28 days.

[0078] Example 5 - Pulp modification with ε-caprolactone using HC mixer The pulp was preactivated by mercerization using 20 wt.% sodium hydroxide, dried and powdered in a single-step drying / grinding reactor. The pulp consistency before the addition of ε-caprolactone was 84%. The NaOH solution was partially removed. The reaction was allowed to proceed in the presence of NaOH as a basic catalyst at a temperature of 120° C. for 1 hour, as shown in Scheme 1 below. The resulting product was filtered, washed and dried. [Table 2] [ka]

[0079] Scheme 1. Reaction of cellulose with ε-caprolactone in mercerized pulp.

[0080] It is obvious to those skilled in the art that with the advancement of technology, the basic concept can be implemented in various ways. Therefore, the embodiments are not limited to the above examples. Instead, the embodiments can vary within the scope of the claims.

[0081] The above-mentioned embodiments may be used in any combination with each other. Some of the embodiments may be combined to form further embodiments. The method, product or use disclosed herein may include at least one of the embodiments described herein above. It will be understood that the benefits and advantages described above may relate to one embodiment or to several embodiments. The embodiments are not limited to those that solve any or all of the problems described or those that have any or all of the benefits and advantages described. It will be further understood that a reference to "an" item refers to one or more of the items. The term "comprising" is used herein to mean including one or more of the preceding features or operations without excluding the presence of one or more additional features or operations.

Claims

1. A method for preparing a thermoplastic composition comprising grafted cellulose and / or hemicellulose, the method comprising reacting a cyclic ester monomer with cellulose and / or hemicellulose, thereby at least partially grafting the cellulose and / or hemicellulose with the cyclic ester monomer, thereby forming the thermoplastic composition.

2. 10. The method of claim 1, wherein the thermoplastic composition is biodegradable as determined by OECD Standard 301 F for the testing of chemicals.

3. 2. The method of claim 1, wherein the cyclic ester monomer is a lactone such as ε-caprolactone, γ-valerolactone, δ-valerolactone, or a mixture of two or more lactones, or any mixture or combination thereof.

4. The cyclic ester monomer is represented by formula (I) or (II): 【Chemistry 1】 【Chemistry 2】 (In the formula, R １ and R ２ are each independently selected from the group consisting of H, methyl, ethyl, and propyl; R ３ and R ４ are each independently selected from the group consisting of H, methyl, ethyl, and propyl; A is selected from O and N; R ５ is selected from the group consisting of H, methyl, ethyl and propyl when A is N; R ５ is non-existent if A is O, m is an integer ranging from 1 to 5.

2. The method of claim 1, wherein the lactone is selected from lactones represented by

5. The method of claim 1 , wherein the cyclic ester monomer is reacted with a mixture comprising the cellulose and the hemicellulose, such as a chemical pulp.

6. 2. The method of claim 1, wherein the cellulose and / or hemicellulose, or the mixture, when reacted with the cyclic ester monomer is dried and powdered cellulose and / or hemicellulose, such as dried and powdered chemical pulp.

7. 2. The method of claim 1, wherein the cellulose and / or hemicellulose, or the mixture, is pretreated by thermal, mechanical, physical and / or chemical means, such as by drying, refining, milling, fluffing and / or mercerization, and then reacted with the cyclic ester monomer.

8. 10. The method of claim 1, wherein the cyclic ester monomer is reacted with the cellulose and / or hemicellulose, or the mixture, in the presence of an acidic or basic catalyst.

9. 10. The method of claim 1, wherein the cyclic ester monomer is reacted with the cellulose and / or hemicellulose, or the mixture, at a temperature in the range of about 50 to 210°C, or in the range of about 100 to 160°C, or in the range of 110 to 140°C.

10. 10. The method of claim 1, wherein the cyclic ester monomer is reacted with the cellulose and / or hemicellulose, or the mixture, for at least 5 minutes, at least 1 hour, or at least 5 hours, or about 1 to 5 hours.

11. 2. The method of claim 1, wherein no additional solvent is included or added to the cyclic ester monomer and the cellulose and / or hemicellulose, or the mixture, when they are reacted.

12. 10. The method of claim 1, further comprising pelletizing the thermoplastic composition or forming a powder, film, filament, melt, and / or 3D shape of the thermoplastic composition.

13. A thermoplastic composition comprising cellulose and / or hemicellulose grafted with a polyester, such as a polylactone, which is biodegradable.

14. The thermoplastic composition of claim 13, obtainable by the method of claim 1.

15. 14. The method of claim 1 or the thermoplastic composition of claim 13, wherein the degree of substitution of the composition and / or the grafted cellulose and / or hemicellulose is in the range of 0.05 to 2.5, or 0.1 to 2, or 0.5 to 1.

5.

16. The method of claim 1 or the thermoplastic composition of claim 13, wherein the melting temperature of the thermoplastic composition is in the range of 40 to 230°C.

17. 14. The method of claim 1 or the thermoplastic composition of claim 13, wherein the lactone content of the thermoplastic composition is in the range of 0.1 to 1000, or 0.1 to 200, or 0.5 to 200 (wt % pulp).

18. A thermoplastic polymer material comprising or formed from the thermoplastic composition of claim 13, optionally further comprising a biocomposite, a second thermoplastic material, a plastic and / or an additive.

19. An article obtainable from or formed from the thermoplastic composition of claim 13 and / or the thermoplastic polymer material of claim 18.

20. 20. The article of claim 19, which is a pellet, powder, film, filament, melt, 3D shape, coating, hot melt adhesive, container, casing, packaging article, film label, paper, medical device, plastic or composite profile, and / or 3D printing filament.

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