A thermoplastic composition and the use of a compatibilization agent

Abstract

A thermoplastic composition prepared from at least a polymer, a lignin-based filler, and a compatibilization agent is disclosed. Further is disclosed the use of a compatibilization agent in the production of a thermo-plastic composition for increasing the yield strength value of the thermoplastic composition. Further, is disclosed an article and the use of the thermoplastic composition.

Description

[0001] A THERMOPLASTIC COMPOSITION AND THE USE OF A COMPATI-

[0002] BILIZATION AGENT

[0003] TECHNICAL FIELD

[0004] The present disclosure relates to a thermoplastic composition . Further, the present disclosure relates to the use of a compatibi li zation agent in the production of a thermoplastic composition for increasing the yield strength value of the thermoplastic composition . The present disclosure further relates to an article and to the use of the thermoplastic composition .

[0005] BACKGROUND

[0006] Sustainability of the components of plastic production is of importance and there is a need for biobased and renewable components in plastics . Therefore , the inventors have recogni zed an ongoing need to find sustainable solutions for producing thermoplastic compositions having an increased amount of renewable components for use in different applications .

[0007] SUMMARY

[0008] Disclosed is a thermoplastic composition prepared from at least a polymer, lignin-based filler, and a compatibili zation agent , wherein the compatibili zation agent is maleic anhydride (MAH) grafted polymer, maleic anhydride co-polymer, glycidyl methacrylate (GMA) grafted polymer, glycidyl methacrylate co-poly- mer, or a combination or mixture of at least two of these , and wherein :

[0009] - the total amount of lignin-based filler used in the thermoplastic composition is 7 . 5 - 65 weight-% ,

[0010] - the total amount of the compatibili zation agent used in the thermoplastic composition is 0 . 1 - 10 weight-% , and the thermoplastic composition exhibits a yield strength value that is at least 10 % higher than the yield strength value of a corresponding thermoplastic composition, wherein the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but wherein no compatibili za- tion agent is used .

[0011] Further is di sclosed the use of a compatibi l- i zation agent , wherein the compatibili zation agent is maleic anhydride grafted polymer, maleic anhydride copolymer, glycidyl methacrylate grafted polymer, glyc- idyl methacrylate co-polymer, or a combination or mixture of at least two of these , together with at least a polymer and a l ignin-based fi ller in the production of a thermoplastic composition for increasing the yield strength value of the thermoplastic composition by at least 10 % compared to the yield strength value of a corresponding thermoplastic composition, wherein the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but wherein no compatibili zation agent is used .

[0012] Further is disclosed an article comprising the thermoplastic composition as defined in the current specification .

[0013] Further is disclosed the use of the thermoplastic composition as defined in the current specification in a packaging, a housing, an automotive part , an aviation part , a marine part , a machine part , a sports equipment , a sports equipment part , a leisure equipment , a leisure equipment part , a tool , a part of a tool , a pipe , a membrane , a tube , a fitting, a bottle , a film, a bag, a sack, a textile , a rope , a container, a tank, an electrical component , an electronic component , a part for energy generation, a toy, an appliance , a kitchenware , a tableware , a flooring, a fabric, a medical application, a food contact material , a construction material , a drinking water application, and / or a furniture .

[0014] DETAILED DESCRIPTION

[0015] The present disclosure relates to a thermoplastic composition prepared from at least a polymer, lignin-based filler, and a compatibili zation agent , wherein the compatibili zation agent is maleic anhydride grafted polymer, maleic anhydride co-polymer, glycidyl methacrylate grafted polymer, glycidyl methacrylate copolymer, or a combination or mixture of at least two of these , and wherein :

[0016] - the total amount of lignin-based filler used in the thermoplastic composition is 7 . 5 - 65 weight-% ,

[0017] - the total amount of the compatibili zation agent used in the thermoplastic composition is 0 . 1 - 10 weight-% , and the thermoplastic composition exhibits a yield strength value that is at least 10 % higher than the yield strength value of a corresponding thermoplastic composition, wherein the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but wherein no compatibili zation agent is used .

[0018] The present disclosure further relates to the use of a compatibili zation agent , wherein the compatibili zation agent is maleic anhydride grafted polymer, maleic anhydride co-polymer, glycidyl methacrylate grafted polymer, glycidyl methacrylate co-polymer, or a combination or mixture of at least two of these , together with at least a polymer and a lignin-based filler in the production of a thermoplastic composition for increasing the yield strength value of the thermoplastic composition by at least 10 % compared to the yield strength value of a corresponding thermoplastic composition, wherein the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but wherein no compat- ibili zation agent is used .

[0019] Thus , the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but without using any compatibili zation agent . The amount of compatibili zation agent used in preparing the thermoplastic composition is replaced with using a corresponding additional amount of the polymer instead in the corresponding thermoplastic composition . The corresponding thermoplastic composition is a reference thermoplastic composition . The corresponding thermoplastic composition is prepared in the corresponding way as the thermoplastic composition disclosed in the current specification, except that the compatibili zation agent is excluded . The amount of compatibili zation agent used in the thermoplastic composition is replaced with an equal amount of the used polymer instead . The total amount of lignin-based filler is kept the same in the thermoplastic composition and in the corresponding thermoplastic composition . In fact , all other components and their amounts are kept the same in the corresponding thermoplastic composition except that the amount of compatibili zation agent is replaced with a corresponding additional amount of the polymer used .

[0020] The present disclosure further relates to an article comprising the thermoplastic composition as defined in the current specification . In one embodiment , thermoplastic composition has been shaped into the article by extrusion, inj ection molding, compression molding, blow molding, inj ection blow molding, inj ection stretch blow molding, thermoforming, vacuum forming, melt spinning, electrospinning, melt blowing, film blowing, film casting, extrusion coating, rotational molding, coextrusion, laminating, calendering, fused deposition modeling, or by any combination of these.

[0021] The present disclosure further relates to the use of the thermoplastic composition as defined in the current specification in a packaging, a housing, an automotive part, an aviation part, a marine part, a machine part, a sports equipment, a sports equipment part, a leisure equipment, a leisure equipment part, a tool, a part of a tool, a pipe, a membrane, a tube, a fitting, a bottle, a film, a bag, a sack, a textile, a rope, a container, a tank, an electrical component, an electronic component, a part for energy generation, a toy, an appliance, a kitchenware, a tableware, a flooring, a fabric, a medical application, a food contact material, a construction material, a drinking water application, and / or a furniture.

[0022] A thermoplastic composition, or thermosoftening plastic composition as it may also be called, is a plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling.

[0023] The compatibilization agent used for preparing the thermoplastic composition is maleic anhydride grafted polymer, maleic anhydride co-polymer, glycidyl methacrylate grafted polymer, glycidyl methacrylate copolymer, or a combination or mixture of at least two of these. The compatibilization agent is thus a polymer that is grafted or co-polymerized with a reactive monomer. E.g. the maleic anhydride grafted polymer (poly- mer-g-MAH) is produced by grafting maleic anhydride onto the polymer backbone. The backbone may be a polyolefin, such as polyethylene, polypropylene, ethylene-vinyl acetate, but can also be of another type of polymer.

[0024] In one embodiment, the maleic anhydride grafted polymer is maleic anhydride grafted low-density polyethylene (LDPE) , maleic anhydride grafted linear low- density polyethylene (LLDPE) , maleic anhydride grafted high-density polyethylene (HDPE) , maleic anhydride grafted styrene-ethylene-butylene-styrene ( SEBS ) , maleic anhydride grafted polybutylene adipate terephthalate ( PBAT ) , maleic anhydride grafted polylactic acid ( PLA) , maleic anhydride grafted polybutylene succinate ( PBS ) , maleic anhydride grafted polyhydroxybutyrate ( PHB) , maleic anhydride grafted acrylonitrile butadiene styrene (ABS ) , or maleic anhydride grafted styrene-bu- tadiene-styrene ( SBS ) .

[0025] In one embodiment , the maleic anhydride copolymer is maleic anhydride co-polystyrene .

[0026] In one embodiment , the glycidyl methacrylate grafted polymer is glycidyl methacrylate grafted low- density polyethylene (LDPE ) , glycidyl methacrylate grafted linear low-density polyethylene (LLDPE ) , glycidyl methacrylate grafted high-density polyethylene (HDPE ) , glycidyl methacrylate grafted styrene-ethylene- butylene-styrene ( SEBS ) , glycidyl methacrylate grafted polybutylene adipate terephthalate ( PBAT ) , glycidyl methacrylate grafted polylactic acid ( PLA) , glycidyl methacrylate grafted polybutylene succinate ( PBS ) , glycidyl methacrylate grafted polyhydroxybutyrate ( PHB) , glycidyl methacrylate grafted acrylonitrile butadiene styrene (ABS ) , or maleic anhydride grafted sty- rene-butadiene-styrene ( SBS ) .

[0027] In one embodiment , the glycidyl methacrylate co-polymer is glycidyl methacrylate co-polyethylene , glycidyl methacrylate co-polypropylene , glycidyl methacrylate co-acrylonitrile butadiene styrene (ABS ) , glycidyl methacrylate co-polybutylene adipate terephthalate ( PBAT ) , glycidyl methacrylate co-polylactic acid ( PLA) , glycidyl methacrylate co-polybutylene succinate ( PBS ) , or glycidyl methacrylate co-polyhydroxy- butyrate ( PHB) .

[0028] In one embodiment , the maleic anhydride grafted polymer is maleic anhydride grafted polypropylene . In one embodiment , the compatibili zation agent is maleic anhydride grafted polymer . In one embodiment , the com- patibili zation agent is maleic anhydride grafted polypropylene .

[0029] The polymer part of the compatibili zation agent may be the same polymer as the polymer used for preparing the thermoplastic composition, but it does not have to be the same . In one embodiment, the polymer part of the compatibili zation agent is the same polymer as the polymer used in the thermoplastic composition . In one embodiment the polymer of the maleic anhydride grafted polymer is the same polymer as the polymer used in the thermoplastic composition .

[0030] Using lignin-based filler in an increased loading in a thermoplastic composition has the added utility of resulting in a material with increased renewable content and reduced carbon footprint . When increasing the amount of lignin-based filler in the thermoplastic composition the compound stiffness , i . e . Youngs modulus , is increased . However, a drawback has been that the yield strength value , and also yield strain value , are decreasing with increasing the total amount of ligninbased filler in the thermoplastic composition . The inventors surprisingly found out , contrary to the general expectation, that when adding the compatibili zation agent as disclosed in the current specification, e . g . polymer-g-MAH, into the thermoplastic composition, the stiffness of the composition increases as desired but surprisingly the yield strength value does not drop . In addition, addition of the compatibili zation agent as disclosed in the current specification, e . g . polymer-g- MAH, into the lignin-based thermoplastic composition, has the added utility of affecting the yield strain value in a positive manner . As a results , prepared is a thermoplastic composition having a desired stiffness while the increase in brittleness is limited .

[0031] Without bounding to any specific theory why the yield strength value is improved when using the compatibili zation agent , such as polymer-g-MAH, one may consider that this is a result of the lignin-based fi ller being able to better react with the compatibili zation agent , which thus may bind the lignin-based filler to the polymer used .

[0032] The use of the compatibili zation agent as disclosed in the current specification, e . g . polymer-g- MAH, has the further added uti lity of resulting in the thermoplastic composition exhibiting a reduced pressure filter value which indicates a better dispersion of the lignin-based filler . The addition of compatibili zation agent as disclosed in the current specification, e . g . polymer-g-MAH, thus may allow to further improve the dispersion of the lignin-based filler . Better dispersion of the lignin-based filler may then have a positive effect on the yield strength value and yield strain value of the thermoplastic composition .

[0033] The total amount of lignin-based filler used in the thermoplastic composition may be 7 . 5 - 65 weight- % , or 10 - 60 weight-% , or 12 - 55 weight-% , or 14 - 45 weight-% , or 15 - 35 weight-% . Using a higher total amount of the lignin-based filler has the added utility of the renewable content of the thermoplastic composition is thus increased . The inventors surprisingly found out that the use of the compatibili zation agent as disclosed in the current specification in the production of the thermoplastic composition has the added utility of enabling an even higher content of lignin-based filler to be used in a thermoplastic composition without having to compromise the properties of the produced thermoplastic composition . Thus , a thermoplastic composition having a higher share of lignin-based filler can be produced . Thus , the use the compatibili zation agent as disclosed in the current specification, e . g . polymer- g-MAH, enables to produce a thermoplastic composition with high content of renewable materials and improved carbon footprint in combination with mechanical properties needed in further applications thereof.

[0034] In one embodiment, the total amount of the com- patibilization agent used in the thermoplastic composition is 0.1 - 10 weight-%, or 0.5 - 8 weight-%, or 1 - 6 weight-%, or 2 - 5.5 weight-%, or 2.5 - 5 weight-%. The inventors surprisingly noted that a rather low amount of the compatibilization agent as disclosed in the current specification may be used for achieving the desired effect of improving the yield strength value and the yield strain value.

[0035] The total amount of the polymer used in the thermoplastic composition may be 25 - 92.4 weight-%, or 40 - 80 weight-%, or 50 - 75 weight-%.

[0036] In one embodiment, the thermoplastic composition exhibits a yield strength value that is that is at least 10 % , or at least 15 % , or at least 20 % , or at least 30 % , or at least 45 % , higher than the yield strength value of a corresponding thermoplastic composition. In one embodiment, the thermoplastic composition exhibits a yield strength value that is 10 - 500 % , or 15 - 400 % , or 20 - 350 % , higher than the yield strength value of a corresponding thermoplastic composition.

[0037] In one embodiment, the compatibilization agent is used for increasing the yield strength value of the thermoplastic composition by at least 10 %, or at least 15 % , or at least 20 % , or at least 30 % , or at least 45 % , compared to the yield strength value of a corresponding thermoplastic composition. In one embodiment, the compatibilization agent is used for increasing the yield strength value of the thermoplastic composition by 10 - 500 %, or 15 - 400 %, or 20 - 350 %, compared to the yield strength value of a corresponding thermoplastic composition.

[0038] The yield strength value of the thermoplastic composition can be determined by DIN EN ISO 527- 2:2012. In one embodiment, the thermoplastic composition exhibits a yield strain value that is at least 5 % , or at least 7.5 %, or at least 10 % , higher than the yield strain value of a corresponding thermoplastic composition. In one embodiment, the thermoplastic composition exhibits a yield strain value that is 5 - 350 % , or 7.5 - 300 % , or 10 - 250 % , higher than the yield strain value of a corresponding thermoplastic composition.

[0039] In one embodiment, the compatibilization agent is used for increasing the yield strain value of the thermoplastic composition by at least 5 % , or at least 7.5 % , or at least 10 % , compared to the yield strain value of a corresponding thermoplastic composition. In one embodiment, the compatibilization agent is used for increasing the yield strain value of the thermoplastic composition by 5 - 350 %, or 7.5 - 300 %, or 10 - 250 % , compared to the yield strain value of a corresponding thermoplastic composition.

[0040] The yield strain value of the thermoplastic composition can be determined by DIN EN ISO 527-2:2012.

[0041] The thermoplastic composition may further exhibit a pressure filter value that is at least 30 % , at least 40 % , at least 50 % , lower than the pressure filter value of a corresponding thermoplastic composition. The pressure filter value of the thermoplastic composition can be determined by ISO 23900-5:2015.

[0042] Also an additive may be used for preparing the thermoplastic composition. The additive may be modified siloxane, amphiphilic copolymer, zinc stearate, or a combination or mixture of at least two of these. The total amount of the additive used in the thermoplastic composition may be 0.1 - 10 weight-%. Using the above additive (s) in the production of the thermoplastic composition may have the added utility of increasing the impact strength value and / or notched impact strength value of the thermoplastic composition. Impact strength value and the notched impact strength value can be determined ISO 179-1:2023.

[0043] Modified siloxane is to be understood as a polysiloxane with an organic modification of the backbone by organic groups or organic side chains, and / or an organic modification of the end groups with an organic group or chain. In one embodiment, the additive is modified siloxane. In one embodiment, the modified siloxane is organically modified siloxane. In one embodiment, the modified siloxane is polyester modified siloxane.

[0044] In one embodiment, the additive is amphiphilic copolymer. Amphiphilic polymers are macromolecules that simultaneously contain hydrophobic and hydrophilic components. Examples of hydrophobic components are polymethyl methacrylate, polymaleimide-methacrylate, polylactic acid, polypropylene oxide, polybutadiene, polybutadiene succiniate etc. Examples of hydrophilic components are polyacrylic acid, polyhydroxyethyl methacylate, polymethacylic acid, poly (polyethylene glycol methacrylate) , polyethylene oxide, polymethylvinylether , polyvinylpyrrolidone etc. Also, other hydrophobic and hydrophilic components may be used.

[0045] In one embodiment, the additive is zinc stearate .

[0046] In one embodiment, the additive is a combination or mixture of modified siloxane, amphiphilic copolymer, and zinc stearate. In one embodiment, the additive is a combination or mixture of modified siloxane and amphiphilic copolymer. In one embodiment, the additive is a combination or mixture of modified siloxane and zinc stearate. In one embodiment, the additive is a combination or mixture of amphiphilic copolymer and zinc stearate .

[0047] In one embodiment, the polymer is polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate (EVA) , polybutylene adipate terephthalate (PBAT) , polyamide, polyacrylate, polyester, acrylonitrile butadiene styrene (ABS ) , polycarbonate, polylactic acid ( PLA) , polyvinyl chloride ( PVC) , styrene-ethylene-bu- tylene-styrene ( SEBS ) , styrene-butadiene-styrene ( SBS ) , or any combination or mixture thereof . I . e . one type of polymer may be used for producing the thermoplastic composition or a combination of two or more different polymers may be used .

[0048] The polymer ( s ) used in the thermoplastic composition may be derived from (a) fossil resource ( s ) . At least one polymer may be derived from ( a) biobased resource ( s ) . The at least one polymer may be derived from a fossil resource or from a biobased resource . All of the polymers used in the thermoplastic composition may be derived either from a fossil source or from a biobased source . Alternatively, polymers from both fossil sources and biobased sources may be used in the thermoplastic composition . Also , a mixture of polymers from both fossil source ( s ) and biobased source ( s ) may be used in the thermoplastic composition .

[0049] In one embodiment , the lignin-based filler is lignin that has been treated by hydrothermal carbonization . The lignin-based filler is prepared from lignin that has been treated by hydrothermal carboni zation treatment (HTC) . In one embodiment , the lignin-based filler comprises or consists of lignin that has been treated by hydrothermal carboni zation treatment .

[0050] Thus , the filler used to make the thermoplastic composition is a lignin-based filler prepared from lignin that has been treated by hydrothermal carboni zation treatment (HTC) . The hydrothermal carboni zation treatment of lignin refers to a thermochemical conversion process of lignin-containing material in an aqueous suspension . Hydrothermal carboni zation treatment of lignin produces lignin derivatives having high carbon content and functional groups .

[0051] Lignin is a biopolymer, that is a key structural material in the supporting tissues of most living plants. It is a renewable material which can be used in several applications.

[0052] The lignin may be derived from any suitable source. The lignin may be derived from e.g. wood, such as hardwood, softwood, broadleaf wood, or their combination, or from any other biomass such as sugarcane. The wood may originate from e.g. pine, poplar, beech, aspen, spruce, eucalyptus, ash, or birch. The wood may also be any combination or mixture of these.

[0053] In one embodiment, the lignin-based filler is prepared from lignin derived from enzymatic hydrolysis process and / or from a Kraft process and subjected to the hydrothermal carbonization treatment. In one embodiment, the lignin-based filler is prepared from lignin derived from enzymatic hydrolysis process and subjected to the hydrothermal carbonization treatment. In one embodiment, the lignin-based filler is prepared from lignin derived from a Kraft process and subjected to the hydrothermal carbonization treatment.

[0054] In one embodiment, the enzymatic hydrolysis process comprises enzymatic hydrolysis of a plant-based feedstock, such as a wood-based feedstock. Prior to the enzymatic hydrolysis the wood-based feedstock may have been processed in a pre-treatment process comprising impregnation and hemihydrolysis before the enzymatic hydrolysis. The pre-treatment process may result in providing cellulose from the wood-based feedstock, which may then be hydrolysed in the enzymatic hydrolysis process .

[0055] In one embodiment, the enzymatic hydrolysis process comprises enzymatic hydrolysis of cellulose. In one embodiment, the lignin-based filler is prepared from lignin derived from pulping of wood, e.g. Kraft lignin.

[0056] The lignin-based filler may be prepared as disclosed below. The lignin to be used may be derived from e.g. a process wherein the lignin is formed in enzymatic hydrolysis of lignocellulosic feedstock or the lignin may be derived from a Kraft process. Also other lignin sources may be used.

[0057] In one embodiment, the starting material for preparing the lignin-based filler is lignin taken from enzymatic hydrolysis process. Enzymatic hydrolysis is a process, wherein enzyme (s) assist (s) in cleaving bonds in molecules with the addition of elements of water. In one embodiment, the enzymatic hydrolysis comprises enzymatic hydrolysis of cellulose. In one embodiment, the lignin-based filler is prepared from lignin derived from enzymatic hydrolysis process that is subjected to hydrothermal carbonization treatment.

[0058] The inventors surprisingly found out that when e.g. lignin from enzymatic hydrolysis process is used for producing the lignin-based filler, one is able to lower the ash content of the lignin-based filler. The lower ash content has the added utility of e.g. higher purity of the lignin-based filler.

[0059] The lignin may originate from second-generation biomass. The second-generation (2G) biomass may be taken to refer to non-edible and non-food biomass. Contrary to the term second-generation biomass, the first- generation biomass is to be taken as edible biomass.

[0060] The derived lignin may be dissolved in alkaline solution, such as NaOH. The dissolution may be accomplished by heating the mixture of lignin and alkaline solution to about 80 °C, adjusting the pH to a value above 7, such as 9 - 11, and mixing the mixture of lignin and alkaline solution for a predetermined time. The mixing time may be continued for about 2 - 3 hours. The exact pH value is determined based on the grade target of the product.

[0061] The dissolved lignin may then be subjected to hydrothermal carbonization treatment (HTC) .

[0062] The hydrothermal carbonization treatment may take place in a reactor (HTC reactor) , or if needed, in several parallel reactors, working in a batchwise manner. The dissolved lignin may be pre-heated before being entered in the HTC reactor (s) . The temperature in the HTC reactor (s) may be 150 - 250 °C and the pressure may be 20 - 30 bar. The residence time in the HTC reactor (s) may be about three to six hours. In the HTC reactor, the lignin is carbonized, whereby a stabilized lignin derivative with a high specific surface area may be precipitated. The formed slurry comprising the carbonized lignin may then be removed and cooled.

[0063] Consequently, a slurry comprising lignin-based filler is formed.

[0064] The slurry comprising lignin-based filler may be fed to a separation unit, wherein the precipitated lignin may be separated from the slurry. The separated lignin-based filler may be dried and recovered. Before drying, the lignin-based filler may be, if needed, washed. The recovered lignin-based filler may be treated further, e.g. crushed, dried further, milled etc. before using as the lignin-based filler. The thus formed lignin-based filler is a renewable and a biobased filler .

[0065] During the above-described process lignin polymers are connected to each other. Thus, the ligninbased filler may be considered to comprise or consist of lignin polymers that are linked together. Lignin polymers that are connected or linked together may not be soluble anymore. However, smaller lignin polymer chains still remain soluble and thus can be subjected to standard analytical techniques like size exclusion chromatography or nuclear magnetic resonance spectroscopy (NMR spectroscopy) , which require the analyte to be dissolved in a solvent. Thus, different properties of the soluble fraction of the lignin-based filler may be determined.

[0066] The lignin-based filler may comprise ash in a total amount of 0.1 - 3 weight-%, or 0.1 - 2.5 weight- % , or 0.2 - 2.0 weight-%, or 0.3 - 1.5 weight-%, or 0.4 1.0 weight-%. The ash content can be determined according to the standard DIN 51719. The inventors surprisingly found out that when e.g. lignin from enzymatic hydrolysis process is used for producing the lignin-based filler, one is able to lower the ash content of the lignin-based filler. The lower ash content has the added utility of e.g. higher purity of the lignin-based filler.

[0067] The lignin-based filler may comprise carbon in a total amount of 62 - 70 weight-%, or 63 - 69 weight- % , or 64 - 68 weight-%. The amount of carbon in the lignin-based filler may be determined according to standard DIN 51732 (1997) .

[0068] The solubility of the lignin-based filler in 0.1 M NaOH may be 1 - 40 weight-%, or 3 - 35 weight-%, or 5 - 30 weight-%. The solubility may be measured in the following manner: First a sample is dried at a temperature of 60 °C for four hours. A sample mass of 0.5 gram is weighed and suspended in 50 ml of 0.1 M NaOH at a concentration of 1 % having a temperature of 22 °C. Mixing is continued for 1 hour, where after the sample is placed on a glass microfiber paper (1.6 pm) and the filter paper with the sample is dried at a temperature of 60 °C for 2 hours. The portion of the sample has which has dissolved can be determined gravimetrically .

[0069] The lignin-based filler may have a weight average molecular weight (Mw) of 1000 - 4000 Da, or 1300

[0070] - 3700 Da, or 1700 - 3200 Da, or 2500 - 3000 Da, or 2600

[0071] - 2900 Da, or 2650 - 2850 Da, when determined based on the soluble fraction of the lignin-based filler. The weight average molecular weight may be determined with size exclusion chromatography (SEC) by using 0.1 M NaOH as eluent and a sample amount of about 1 mg / ml, which is dissolved in 0.1 M NaOH. The molecular weights are measured against polystyrenesulfonate standards. UV detector at wavelength of 280 nm is used. The polydispersity index (PDI) of the ligninbased filler may be 1.5 - 5.0, or 1.8 - 4.5, or 1.9 - 4.3, or 2.1 - 4.0, or 2.4 - 3.5, or 2.6 - 3.2, when determined based on the soluble fraction of the ligninbased filler. The polydispersity index may be determined by size-exclusion chromatography (SEC) . The PDI is a measure of the distribution of molecular mass in a given polymer sample. The PDI is calculated as the weight average molecular weight (Mw) divided by the number average molecular weight (Mn) . PDI indicates the distribution of individual molecular masses in a batch of polymers.

[0072] The lignin-based filler may have a STSA number of 3 - 150 m2 / g, or 5 - 100 m2 / g, or 7 - 60 m2 / g. The STSA number may be determined according to standard ASTM D6556.

[0073] The lignin-based filler may have a density of at most 1.5 g / cm3. In one embodiment, the lignin-based filler has a density of 1.0 - 1.5 g / cm3, or 1.15 - 1.35 g / cm3, or 1.1 - 1.4 g / cm3. The density may be determined according to standard ISO 21687.

[0074] The thermoplastic composition may be prepared by using at least one polymer, lignin-based filler, and compatibilization agent. Further components or materials, such as plasticizers, additives, lubricants, stabilizers, antioxidants, curing agents, blowing agents, etc., may also be used for preparing the thermoplastic composition. In one embodiment, combining the at least one polymer, the lignin-based filler, and the compatibilization agent, comprises also combining one or more plasticizers, additives, lubricants, stabilizers, antioxidants, curing agents, and / or blowing agents, to form the thermoplastic composition.

[0075] When preparing the thermoplastic composition, a so-called masterbatch may first be prepared by using at least the polymer, the lignin-based filler, and the compatibilization agent. The masterbatch may be prepared by mixing the polymer, the lignin-based filler, and the compatibilization agent at an elevated temperature. Also other plasticizers, additives, lubricants, stabilizer, antioxidants, curing agents, blowing agents, etc. as needed may be included in the masterbatch. Also other filler (s) in addition to the lignin-based filler may be used. The other filler (s) may be used in a total amount of 0.1 - 60 weight-%. Combinations with other fillers may be thus used in various ratios. Talc, chalk, carbon black or other pigments, polymer fibers, natural fibers, biobased fibers, and glass fibers may be mentioned as examples of such other fillers. A masterbatch is generally considered a solid product (normally of plastic, rubber, or elastomer) in which pigments or fillers are optimally dispersed at high concentration in a carrier material. The carrier material is compatible with the main polymer in which it will be blended during compounding or the following molding, whereby the final plastic product, i.e. the thermoplastic composition, obtains the color or properties from the masterbatch.

[0076] Alternatively, the thermoplastic composition may be directly compounded at an elevated temperature from the polymer, the lignin-based filler, and the compatibilization agent. Also other additives, lubricants, stabilizers, antioxidants, curing agents, blowing agents, other fillers etc. as needed may be directly compounded with the polymer, the lignin-based filler, and the compatibilization agent. Alternatively, they may be compounded as a masterbatch with the polymer, the lignin-based filler, and the compatibilization agent.

[0077] However, in one embodiment, no other filler than the lignin-based filler is used for preparing the thermoplastic composition.

[0078] The temperature used when combining the components may vary depending on the type of polymer used. The suitable temperature to be used for each polymer is readily available to the person skilled in the art . Also the polymer providers define suitable processing temperatures for different polymers . Generally, temperatures of e . g . 20 - 350 ° C, or 40 - 330 ° C, or 70 - 300 ° C, or 120 - 280 ° C, or 150 - 260 ° C , may be used .

[0079] Some components of the thermoplastic composition may be cured at an elevated temperature during mixing of the components .

[0080] The thermoplastic composition may be nonexpanded or expanded . When the thermoplastic composition is expanded it may be taken to have the form of a foam . The expanded thermoplastic composition may be formed by introducing pockets of air or gas (e . g . CO2 ) into the thermoplastic composition when being prepared . E . g . blowing agent ( s ) may be used to expand the thermoplastic composition in order to cause it to foam . Polymer foaming is a process where gas filled cells , bubbles , are introduced to the material structure . With foaming, density of a material can be reduced as less material is consumed . In addition, density of the foam can be controlled, and a broad range of densities can be produced based on the product requirements . This results in reduction of weight and material costs . The expanded thermoplastic composition may also be known as or called foamed thermoplastic composition or polymer foam .

[0081] The thermoplastic composition may further be shaped into an article by extrusion, inj ection molding, compression molding, blow molding, inj ection blow molding, inj ection stretch blow molding, thermoforming, vacuum forming, melt spinning, electrospinning, melt blowing, film blowing, film casting, extrusion coating, rotational molding, coextrusion, laminating, calendering, fused deposition modeling, or by any combination of these .

[0082] The total organic carbon content of the thermoplastic composition may be 4 - 100 % as determined according to DIN EN 15936 : 2012 - 11 . The term "total organic carbon ( TOC) " may be taken as the amount of carbon found in an organic compound or in this case in the thermoplastic composition .

[0083] The amount of renewable materials in the thermoplastic composition may be at least 7 . 5 weight-% , or at least 10 weight-% , or at least 15 weight-% , or at least 20 weight-% .

[0084] Using the compatibili zation agent as disclosed in the current specification, such as polymer-g-MAH, in a thermoplastic composition has the added utility of the stiffness of the thermoplastic composition being increased while ensuring that the yield strength value does not drop to an unsuitable level .

[0085] The use of the compatibili zation agents as disclosed in the current specification, such as polymer-g- MAH, in the production of the thermoplastic composition has the added utility of enabling an even higher content of lignin-based filler to be used in a thermoplastic composition without having to compromise the mechanical properties of the produced thermoplastic composition .

[0086] The thermoplastic composition as disclosed in the current specification has the added utility of having a high share of renewable material and exhibiting an improved carbon footprint, while simultaneously having mechanical properties required for the further use of the thermoplastic composition .

[0087] EXAMPLES

[0088] Reference will now be made in detail to the described embodiments .

[0089] The description below discloses some embodiments in such a detail that a person skilled in the art is able to uti li ze the method based on the di sclosure . Not all steps of the embodiments are discussed in detail , as some of the steps will be obvious for the person skilled in the art based on this specification . Example 1 - Preparing thermoplastic compositions

[0090] In this example different thermoplastic compositions were prepared by using varying amounts of lignin-based filler (LBF) (prepared from lignin that has been treated by hydrothermal carbonization treatment ) . Polymer-g-MAH was used as the compatibili zation agent for producing the test example thermoplastic compositions . The corresponding thermoplastic composition was prepared in an otherwise similar manner as the example thermoplastic composition but without using any compatibili zation agent . The amount of compatibili zation agent used in the thermoplastic composition was replaced with a further amount of polymer . Comparative examples were also prepared by using different compatibili zation agents . The polymer used in all the composition was polypropylene ( PP) and the polymer-g-MAH was maleic anhydride grafted polypropylene ( PP-g-MAH) . The prepared compositions are presented in table 1 and table 2 below :

[0091] Table 1 . Prepared thermoplastic compositions by using 15 weight-% of lignin-based filler

[0092] PP: Moplen HP501L (Lyondellbasell )

[0093] PP-co-PE wax: Licocene PP1602 GR (Clariant) amphiphilic copolymer: Tegomer P121 (Evonik) PP-g-MAH: Licocene PPMA7452 GR (Clariant)

[0094] Table 2. Prepared thermoplastic compositions by using 30 weight-% of lignin-based filler

[0095] Properties of the prepared thermoplastic com- positions were tested as follows:

[0096] Yield strength value was measured with DIN EN ISO 527-

[0097] 2:2012 Yield strain value was measured with DIN EN ISO 527- 2:2012

[0098] Pressure filter value was measured with ISO 23900-5:2015

[0099] Youngs modulus value was measured with DIN EN ISO 527- 2:2012

[0100] The measured values are presented in Table 3.

[0101] The measured values of example thermoplastic composition and the comparative examples were compared to the meas- ured values of the corresponding thermoplastic composition to calculate the change in the values relative to the corresponding thermoplastic composition (Table 4) .

[0102] The results of the measurements and calculations are presented below in Table 3 and Table 4 :

[0103] Table 3. Measured values of the prepared thermoplastic compositions

[0104]

[0105] Table 4 . Calculated change in values of the prepared thermoplastic compositions

[0106]

[0107] From the above tables one can see that the use of polymer-g-MAH as the compatibili zation agent clearly improved the yield strength value as wel l as the yield strain value of the thermoplastic composition . Also the pressure filter value was on a good level for the thermoplastic composition .

[0108] It is obvious to a person skil led in the art that with the advancement of technology, the basic idea may be implemented in various ways . The embodiments are thus not limited to the examples described above ; instead they may vary within the scope of the claims .

[0109] The embodiments described hereinbefore may be used in any combination with each other . Several of the embodiments may be combined together to form a further embodiment . A thermoplastic composition, an article , and use , as disclosed herein, may comprise at least one of the embodiments described hereinbefore . It will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments . The embodiments are not limited to those that solve any or all of the stated problems or those that have any or all of the stated benefits and advantages . It will further be understood that reference to "an" item refers to one or more of those items . The term "comprising" is used in this specification to mean including the feature ( s ) or act ( s ) followed thereafter, without excluding the presence of one or more additional features or acts .

Claims

CLAIMS1 . A thermoplastic composition prepared from at least a polymer, a lignin-based filler, and a com- patibili zation agent , wherein the compatibili zation agent is maleic anhydride grafted polymer, maleic anhydride co-polymer, glycidyl methacrylate grafted polymer, glycidyl methacrylate co-polymer, or a combination or mixture of at least two of these , and wherein :- the total amount of lignin-based filler used in the thermoplastic composition is 7 . 5 - 65 weight-% ,- the total amount of the compatibili zation agent used in the thermoplastic composition is 0 . 1 - 10 weight-% , and the thermoplastic composition exhibits a yield strength value that is at least 10 % higher than the yield strength value of a corresponding thermoplastic composition, wherein the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but wherein no compatibili zation agent is used .2 . The thermoplastic composition of claim 1 , wherein the total amount of lignin-based filler used in the thermoplastic composition is 10 - 60 weight-% , or 12 - 55 weight-% , or 14 - 45 weight-% , or 15 - 35 weight-3 . The thermoplastic composition of any one of the preceding claims , wherein the total amount of the compatibili zation agent used in the thermoplastic composition is 0 . 5 - 8 weight-% , or 1 - 6 weight-% , or 2 - 5 . 5 weight-% , or 2 . 5 - 5 weight-% .4 . The thermoplastic composition of any one of the preceding claims , wherein the thermoplastic composition exhibits a yield strength value that is at least 15 % , or at least 20 % , or at least 30 % , or at least 45 % , higher than the yield strength value of a corresponding thermoplastic composition .5 . The thermoplastic composition of any one of the preceding claims , wherein the thermoplastic composition exhibits a yield strain value that is at least 5 % , or at least 7 . 5 % , or at least 10 % , higher than the yield strain value of a corresponding thermoplastic composition .6 . The thermoplastic composition of any one of the preceding claims , wherein the polymer is polyethylene , polypropylene , polystyrene , ethylene-vinyl acetate (EVA) , polybutylene adipate terephthalate ( PBAT ) , polyamide , polyacrylate , polyester, acrylonitrile butadiene styrene (ABS ) , polycarbonate , polylactic acid ( PLA) , polyvinyl chloride ( PVC) , styrene-ethylene-bu- tylene-styrene ( SEBS ) , styrene-butadiene-styrene ( SBS ) , or any combination or mixture thereof .7 . The thermoplastic composition of any one of the preceding claims , wherein lignin-based filler is lignin that has been treated by hydrothermal carboni zation .8 . The thermoplastic composition of any one of the preceding claims , wherein the maleic anhydride grafted polymer is maleic anhydride grafted polypropylene .9 . The use of a compatibili zation agent , wherein the compatibili zation agent is maleic anhydride grafted polymer, maleic anhydride co-polymer, glycidyl methacrylate grafted polymer, glycidyl methacrylate copolymer, or a combination or mixture of at least two of these , together with at least a polymer and lignin-based filler in the production of a thermoplastic composition for increasing the yield strength value of the thermoplastic composition by at least 10 % compared to the yield strength value of a corresponding thermoplastic composition, wherein the corresponding thermoplastic composition is prepared in an otherwise similar manner as the thermoplastic composition but wherein no compatibili zation agent is used .

10. The use of claim 9, wherein the total amount of lignin-based filler used in the thermoplastic composition is 7.5 - 65 weight-%, or 10 - 60 weight-%, or 12 - 55 weight-%, or 14 - 45 weight-%, or 15 - 35 weight-% .

11. The use of any one of claims 9 - 10, wherein the total amount of the compatibilization agent used in the thermoplastic composition is 0.1 - 10 weight-%, or 0.5 - 8 weight-%, or 1 - 6 weight-%, or 2 - 5.5 weight- % , or 2.5 - 5 weight-%.

12. The use of any one of claims 9 - 11 for increasing the yield strength value of the thermoplastic composition by at least 15 % , or at least 20 % , or at least 30 % , or at least 45 % , compared to the yield strength value of the corresponding thermoplastic composition.

13. The use of any one of claims 9 - 12 for increasing the yield strain value of the thermoplastic composition by at least 5 % , or at least 7.5 % , or at least 10 % , compared to the yield strain value of the corresponding thermoplastic composition.

14. The use of any one of claims 9 - 13, wherein the maleic anhydride grafted polymer is maleic anhydride grafted polypropylene.

15. The use of any one of claims 9 - 14, wherein the polymer is polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate (EVA) , polybutylene adipate terephthalate (PBAT) , polyamide, polyacrylate, polyester, acrylonitrile butadiene styrene (ABS) , polycarbonate, polylactic acid (PLA) , polyvinyl chloride (PVC) , styrene-ethylene-butylene-styrene (SEBS) , sty- rene-butadiene-styrene (SBS) , or any combination or mixture thereof.

16. The use of any one of claims 9 - 15, wherein the lignin-based filler is lignin that has been treated by hydrothermal carbonization treatment.

17. An article comprising the thermoplastic composition of any one of claims 1 - 8.

18. The article of claim 17, wherein thermoplastic composition has been shaped into the article by extrusion, injection molding, compression molding, blow molding, injection blow molding, injection stretch blow molding, thermoforming, vacuum forming, melt spinning, electrospinning, melt blowing, film blowing, film casting, extrusion coating, rotational molding, coextrusion, laminating, calendering, fused deposition modeling, or by any combination of these.

19. The use of the thermoplastic composition of any one of claims 1 - 8 in a packaging, a housing, an automotive part, an aviation part, a marine part, a machine part, a sports equipment, a sports equipment part, a leisure equipment, a leisure equipment part, a tool, a part of a tool, a pipe, a membrane, a tube, a fitting, a bottle, a film, a bag, a sack, a textile, a rope, a container, a tank, an electrical component, an electronic component, a part for energy generation, a toy, an appliance, a kitchenware, a tableware, a flooring, a fabric, a medical application, a food contact material, a construction material, a drinking water application, and / or a furniture.

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