Packaging material

Abstract

The invention relates inter alia, to method of preparing a packaging material, as well as to packaging materials produced by the method and uses of said packaging materials in a package. The methods of preparing a packaging material, comprise the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises the resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises: about 5-15 wt% starch or a starch derivative, about 1-20 wt% crosslinker by weight of starch, about 0.5-9 wt% plasticiser by weight of starch, and about 80- 94 wt% solvent.

Description

PACKAGING MATERIALRELATED APPLICATIONS

[0001] The present application claims priority from Australian Provisional Patent Application No. 2024904080, the entire contents of which have been incorporated herein by reference.FIELD OF THE INVENTION

[0002] The present invention relates to packaging materials, methods of making packaging materials and uses of packaging materials. However, it will be appreciated that the invention is not limited to this particular field of use.BACKGROUND OF THE INVENTION

[0003] The following discussion of the prior art is provided to place the invention in an appropriate technical context and enable the advantages of it to be more fully understood. It should be appreciated, however, that any discussion of the prior art throughout the specification should not be considered as an express or implied admission that such prior art is widely known or forms part of the common general knowledge in the field.

[0004] The majority of packaging materials are produced from petroleum-based plastics, which are known to have a significant negative environmental impact due to their poor biodegradability and the environmental damage associated with petroleum production. Packaging materials prepared from natural polymers (“biopolymers”) and fibers may offer an alternative to petroleum-based plastic packaging, as they are generally more environmentally friendly and biodegradable.

[0005] In some cases, fibers are used in packaging materials in order to provide strength, stiffness and / or durability. However, many composite materials use synthetic fibers such as nylon, acrylic and polyester, which are not biodegradable. While some packaging materials may utilise natural fibers (e.g. cotton, hemp and wool) which are more biodegradable, natural fibers can exhibit moisture sensitivity, thermal sensitivity, poor compatibility with polymers and lower durability, causing complications in the manufacturing process.

[0006] It is an object of the present invention to overcome or ameliorate one or more the disadvantages of the prior art, or at least to provide a useful alternative.SUMMARY OF THE INVENTION

[0007] According to a first aspect, the present invention provides a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch, and• about 80-94 wt% solvent.

[0008] In some embodiments, the present invention advantageously provides a scalable method of preparing a biodegradable, home-compostable packaging material made from natural fibers impregnated with a starch-based resin. The packaging materials prepared according to the present methods preferably provide sufficient structural rigidity for packaging applications and have tuneable flexibility based on the particular resin composition. In preferred embodiments, the present methods allow for use of a compression moulding apparatus which does not include a lubricating coating such as Teflon® (Polytetrafluoroethylene - PTFE) in the moulding cavity. This advantageously allows for faster mould production and reduces the need for toxic lubricating coatings.

[0009] In some embodiments, the crosslinker is selected from the group consisting of: citric acid, maleic anhydride, succinic acid and tartaric acid.

[0010] In some embodiments, the plasticiser is selected from the group consisting of: glycerol, sorbitol, mannitol xylitol, polyethylene glycol (PEG), urea, fructose, sucrose, oxidised sucrose and formamide.

[0011] In some embodiments, the solvent is water. In some embodiments, the solvent is an aqueous solution.

[0012] In some embodiments, the resin comprises:• about 5- 15 wt% starch ,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch, and• about 80-94 wt% water.

[0013] In some embodiments, the resin further comprises an auxiliary agent selected from the group consisting of: microcrystalline cellulose, talc, kaolin clay, beeswax, carnauba wax, stearic acid, fatty acid salts, glycerol monostearate, urea, vegetable oils, and epoxidised oils.

[0014] In some embodiments, the resin further comprises an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, urea and sunflower oil.

[0015] In some embodiments, the resin comprises two or more crosslinkers. In one embodiment, the resin comprises one crosslinker.

[0016] In some embodiments, the resin comprises two or more plasticisers. In one embodiment, the resin comprises one plasticiser.

[0017] In some embodiments, the resin comprises two or more solvents. In one embodiment, the resin comprises one solvent.

[0018] In some embodiments, the fiber is a natural fiber. In one embodiment, the natural fiber is selected from the group consisting of: jute, hessian, burlap, cotton, hemp, linen, coir, bamboo fiber, sisal, ramie, wool, flax, abaca and bagasse. In one embodiment, the natural fiber is selected from the group consisting of jute, hessian and burlap.

[0019] In some embodiments, the fiber is a woven fiber. In some embodiments, the fiber is a non-woven fiber.

[0020] In some embodiments, the fiber is woven jute fiber.

[0021] In some embodiments, the impregnated fiber comprises the resin in an amount of about 65 wt%.

[0022] In some embodiments, the curing is performed by oven drying or by compression moulding.

[0023] In some embodiments, the curing is performed at a temperature from about 100°C to about 400°C.

[0024] In some embodiments, the curing is performed at a temperature from about 300°C to about 350°C.

[0025] In a second aspect of the invention, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; andb) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• about 80-94 wt% water.

[0026] In some embodiments, the packaging material is compostable.

[0027] In a third aspect of the invention, there is provided a packaging material produced according to the method of the first or second aspects.

[0028] In a fourth aspect, there is provided a use of the packaging material of the third aspect in a package. The package may be, for example, a box. The packaging material may be an insert for a box.

[0029] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch, and• about 80-94 wt% solvent.

[0030] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 55-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 8-12 wt% starch,• about 8-12 wt% citric acid by weight of starch,• about 2-4 wt% glycerol by weight of starch,• about 86-90 wt% solvent.

[0031] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of about 65 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material; wherein the resin comprises:• about 8-12 wt% starch,• about 8-12 wt% citric acid by weight of starch,• about 2-4 wt% glycerol by weight of starch, and• about 86-90 wt% solvent.

[0032] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of about 65 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 10 wt% starch,• about 10 wt% citric acid by weight of starch,• about 3 wt% glycerol by weight of starch, and• about 89 wt% water.

[0033] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• an auxiliary agent selected from the group consisting of: microcrystalline cellulose, talc, kaolin clay, beeswax, carnauba wax, stearic acid, fatty acid salts, glycerol monostearate, urea, vegetable oils, epoxidised oils, and• a solvent.

[0034] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, urea and sunflower oil, and• a solvent.

[0035] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• a release agent selected from the group consisting of: microcrystalline cellulose, kaolin clay and sunflower oil, and• a solvent.

[0036] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of:a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• urea, and• a solvent.

[0037] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, urea and sunflower oil, and• a solvent.

[0038] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• a release agent selected from the group consisting of: microcrystalline cellulose, kaolin clay and sunflower oil, anda solvent.

[0039] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• urea, and• a solvent.

[0040] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• an auxiliary agent selected from the group consisting of: microcrystalline cellulose, talc, kaolin clay, beeswax, carnauba wax, stearic acid, fatty acid salts, glycerol monostearate, urea, vegetable oils, epoxidised oils, and• a solvent.

[0041] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material.wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, urea and sunflower oil, and• a solvent.

[0042] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• a release agent selected from the group consisting of: microcrystalline cellulose, kaolin clay and sunflower oil, and• a solvent.

[0043] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch,• urea, and• a solvent.

[0044] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, urea and sunflower oil, and• a solvent.

[0045] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• a release agent selected from the group consisting of: microcrystalline cellulose, kaolin clay and sunflower oil, and• a solvent.

[0046] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• urea, and• a solvent.

[0047] In an embodiment of the first aspect, there is provided a method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 55-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material. wherein the resin comprises:• about 8-12 wt% starch,• about 8-12 wt% citric acid by weight of starch,• about 2-4 wt% glycerol by weight of starch, and• about 5-15 wt% microcrystalline cellulose by weight of starch,• a solvent.

[0048] Features of the first to fourth aspects of the invention may be as described below.Starch

[0049] Starch is a polymeric carbohydrate consisting of repeating glucose units joined by glycosidic bonds. Starch comprises about 20% amylose (a linear polysaccharide) and about 80% amylopectin (a branched polysaccharide) based on the plant source it is obtained from. The starch may be obtained from any suitable source. In some embodiments, the starch is selected from the group consisting of: rice starch, wheat starch, corn starch, oat starch, maize starch, barley starch, lentil starch, bean starch, pea starch, potato starch, sweet potato starch and cassava starch, and combinations thereof. In one embodiment, the starch is obtained from a plant source selected from the group consisting of: rice, wheat, corn, oat, maize, barley, lentil, bean, pea, potato, sweet potato and cassava, and combinations thereof. In some embodiments, the starch is corn starch, rice starch, wheat starch, potato starch or tapioca (cassava) starch. In one embodiment, the starch is tapioca (cassava) starch. In one embodiment, the starch is potato starch. In some embodiments the starch is a mixture of one, two, three, four or more different types of starch.

[0050] In some embodiments, the starch is physically or chemically treated prior to use to form a “modified starch” or “starch derivative”. For example, the starch may be treated with an acid or base, bleached using hydrogen peroxide, oxidised, or enzyme treated prior to use. In one embodiment, the modified starch is dextrin. In one embodiment, the starch is not physically or chemically treated prior to use.

[0051] In some embodiments, the resin comprises starch in an amount from about 5 wt% to about 15 wt%, from about 6 wt% to about 14 wt%, from about 7 wt% to about 13 wt%, from about 8 wt% to about 12 wt% or from about 9 wt% to about 11 wt%, or any range in between. In some embodiments, the resin comprises starch in an amount greater than 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14 or 15 wt%. In other embodiments, the resin comprises starch in an amount less than 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6 or 5 wt%. For example, the resin may comprise starch in an amount of about 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14 or 15 wt%. In one embodiment, the resin comprises starch in an amount of about 8, 9, 10, 11 or 12 wt%. In one embodiment, the resin comprises starch in an amount of about 10 wt%.Crosslinker

[0052] Without wishing to be bound by any theory, it is believed that crosslinkers are used in the resin composition to create bonds between the starch chains during curing, thereby modulating the mechanical strength, thermal stability and / or water resistance of the final material. It will be understood that when the amount of crosslinker is too high, the resultant packaging material becomes brittle and has reduced flexibility and mechanical strength. Furthermore, significant excesses of certain crosslinkers (e.g. citric acid at >30% by weight of starch) can in some cases lead to a plasticising effect, resulting in overly flexible materials without sufficient rigidity.

[0053] Crosslinkers with dicarboxylic acid functionality are particularly suitable for use in the resin composition of the present methods. In one embodiment, the crosslinker is selected from the group consisting of: citric acid, maleic anhydride, maleic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, malic acid, fumaric acid, citraconic acid, itaconic acid, glutaric acid, adipic acid, pimelic acid, suberic acid and azelaic acid, and combinations thereof. In some embodiments, the crosslinker is selected from the group consisting of: citric acid, maleic anhydride, maleic acid, succinic acid and tartaric acid, and combinations thereof. In one embodiment, the crosslinker is citric acid. Crosslinkers such as those listed may be used in isolation or in combination as a mixture of two, three, four or more crosslinkers.

[0054] In some embodiments, the resin comprises crosslinker in an amount from about 1% to about 20%, from about 2% to about 19%, from about 3% to about 18%, from about 4% to about17%, from about 5% to about 16%, from about 6% to about 15%, from about 7% to about 14%, from about 8% to about 13%, from about 9% to about 12%, from about 9% to about 11%, from about 1% to about 10%, from about 5% to about 15% or from about 7.5% to about 12.5% by weight of starch, or any range in between. In some embodiments, the resin comprises crosslinker in an amount of greater than 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18 or 19 % by weight of starch. In some embodiments, the resin comprises crosslinker in an amount of less than 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 % by weight of starch. In some embodiments, the resin comprises crosslinker in an amount of about 1 , 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 % by weight of starch. In one embodiment, the resin comprises crosslinker in an amount of about 10% by weight of starch.Plasticiser

[0055] Without wishing to be bound by any theory, it is believed that plasticisers are used to improve plasticity, flexibility and reduce brittleness of the packaging material by weakening intermolecular forces in the starch polymer network. It will be understood that packaging materials made with resin which does not include sufficient plasticiser may result in crystallisation of the starch upon drying and loss of the advantageous properties typically granted by the resin. Additionally, an excess of plasticiser (i.e. 10% or more by starch weight) can lead to overly flexible packaging materials.

[0056] The plasticiser may be a polyol, an amide-based plasticiser, or a sugar. In one embodiment, the polyol is selected from the group consisting of: glycerol, sorbitol, mannitol, xylitol and polyethylene glycol (PEG), or a combination thereof. The amide-based plasticiser may be selected from the group consisting of urea, formamide, and a combination thereof. The sugar may be selected from the group consisting of fructose, sucrose, oxidised sucrose and a combination thereof. In some embodiments, the plasticiser is selected from the group consisting of: glycerol, sorbitol, mannitol, xylitol, polyethylene glycol (PEG), urea, formamide, fructose, sucrose and oxidised sucrose, and a combination thereof. In some embodiments, the plasticiser is selected from the group consisting of: glycerol, sorbitol, mannitol, xylitol and polyethylene glycol (PEG). In some embodiments, the plasticiser is selected from the group consisting of: glycerol and sorbitol. In some embodiments, the plasticiser is glycerol. In some embodiments, the plasticiser is urea. Plasticisers such as those listed may be used in isolation or in combination as a mixture of two, three, four or more plasticisers.

[0057] In some embodiments, the resin comprises plasticiser in an amount from about 0.5% to about 9%, from about 1 % to about 8%, from about 1.5% to about 7%, from about 2% to about 6%, from about 2% to about 5%, from about 2% to about 4% or from about 2% to about 4% by weight of starch, or any range in between. In some embodiments, the resin comprises plasticiserin an amount of greater than 0.5, 1 , 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8 or 8.5 % by weight of starch. In some embodiments, the resin comprises plasticiser in an amount of less than 1 , 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5 or 9 % by weight of starch. In some embodiments, the resin comprises plasticiser in an amount of about 0.5, 1 , 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5 or 9 % by weight of starch. In some embodiments, the resin comprises plasticiser in an amount of about 1 , 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5 or 5.5 % by weight of starch. In some embodiments, the resin comprises plasticiser in an amount of about 3 % by weight of starch.Solvent

[0058] The term “solvent” refers to any liquid capable of maintaining another substance in solution. Without wishing to be bound by any theory, it is believed that solvents are used to suspend the components of the resin composition and provide a medium for them to interact.

[0059] In one embodiment, the solvent is a polar solvent. Advantageously, polar solvents are particularly suitable for use in the resin composition set out in the present methods. The polar solvent may be selected from the group consisting of: water, methanol, ethanol, isopropyl alcohol, acetone and ethyl acetate, or a mixture thereof; or water, methanol, ethanol, isopropyl alcohol, acetone and ethyl acetate. In some embodiments, the polar solvent is selected from the group consisting of: water, ethanol, isopropyl alcohol, or a mixture thereof; or water, ethanol and isopropyl alcohol. In some embodiments, the polar solvent is water. In one embodiment, the solvent is an aqueous solution. Solvents such as those listed may be used in isolation or in combination as a mixture of two, three, four or more solvents.

[0060] It will be understood that the amount of solvent is not particularly limited, and may be determined from the amounts of other ingredients in the resin composition. For example, a resin comprising “10 wt% starch in water” would comprise 10 wt% starch and 90 wt% water, i.e. the solvent represents the remaining mass of the composition. In some embodiments, the resin comprises solvent in an amount from about 80 wt% to about 94 wt%, from about 82 wt% to about 92 wt% or from about 85 wt% to about 90 wt% or any range in between. In some embodiments, the amount of solvent present in the resin is about 80, 81 , 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93 or 94 wt%.Auxiliary agent

[0061] In one embodiment, the resin comprises one or more auxiliary agents. The auxiliary agents may be selected from the group consisting of a release agent, a lubricant, a retrogradation inhibitor, a colouring agent (e.g., a dye), and a filler, and a combination thereof. The resin may comprise at least one or at least two auxiliary agents. The auxiliary agent advantageously maybe included in the resin to modify one or more properties of the resin and / or the packaging material. It will be appreciated that such auxiliary agents may provide advantages such as: improved processability of the resin, improved resin wetting properties, improved fiber impregnation, improved material release from the mould, reduced sticking during curing, enhanced water resistance of the packaging material, enhanced thermal properties of the packaging material and / or enhanced biodegradability.

[0062] In some embodiments, the resin comprises an auxiliary agent in an amount from about 1 % to about 100%, from about 1 % to about 90%, from about 1 % to about 80%, from about 1% to about 70%, from about 1% to about 60%, from about 1% to about 50%, from about 1 % to about 40%, from about 1% to about 30%, from about 1% to about 20%, from about 1% to about 15%, from about 1% to about 10%, from about 2% to about 15%, from about 3% to about 15%, from about 4% to about 15%, from about 5% to about 15%, from about 6% to about 14%, from about 7% to about 13%, from about 8% to about 12% or from about 9% to about 11 % by weight of starch, or any range in between. In some embodiments, the resin comprises an auxiliary agent in an amount of less than 100, 90, 80, 70, 60, 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1% by weight of starch. In some embodiments, the resin comprises an auxiliary agent in an amount of greater than 90, 80, 70, 60, 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1% by weight of starch. In some embodiments, the resin comprises an auxiliary agent in an amount of 100, 90, 80, 70, 60, 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 % by weight of starch. In some embodiments, the resin comprises an auxiliary agent in an amount of 5, 10, 50 or 100% by weight of starch.

[0063] It is understood that in some instances, it is possible for starch-based resins to undergo retrogradation as the resin cools, causing disadvantageous effects on the overall properties of the resin and / or packaging material. The term “starch retrogradation” refers to the process of recrystallisation of the amylase and amylopectin in gelatinised starches upon cooling. In one embodiment, the resin comprises a retrogradation inhibitor. In some embodiments, the retrogradation inhibitor is urea.

[0064] In some embodiments which include a starch retrogradation inhibitor, the amount of starch retrogradation inhibitor may be based on the amount of crosslinker in the resin (i.e. the crosslinkerinhibitor ratio). In some embodiments, the resin comprises a starch retrogradation inhibitor in a crosslinkerinhibitor molar ratio of from about 1 :10 to about 1 :1 , from about 1 :8 to about 1 :1 , from about 1 :6 to about 1 :2, or from about 1 :5 to about 1 :3, or any range in between. In some embodiments, the resin comprises a starch retrogradation inhibitor in a crosslinkerinhibitor ratio of 1 :1 , 1 :2, 1 :3, 1 :4, 1 :5, 1 :6, 1 :7, 1 :8, 1 :9, 1 :10. In some embodiments, the resin comprises a starch retrogradation inhibitor in a crosslinkerinhibitor molar ratio of 1 :3,1 :4 or 1 :5. In some embodiments, the resin comprises a starch retrogradation inhibitor in a crosslinkerinhibitor molar ratio of 1 :3 or 1 :5.

[0065] In one embodiment, the resin comprises a release agent. Without wishing to be bound by any theory, it is understood that including a release agent in the resin composition can reduce the tendency of the resin to adhere to the moulding plates, thereby improving the release properties of impregnated fiber.

[0066] Suitable release agents for use in the resins described herein include powdered solids such as microcrystalline cellulose, talc and kaolin clay, natural waxes such as beeswax and carnauba wax, solid lipids such as stearic acid, oleic acid, linoleic acid, palmitic acid, arachidic acid, fatty acid salts, glycerol monostearate and sorbitan monostearate, oils such as sunflower oil, olive oil, canola oil, flax seed oil, grapeseed oil, soybean oil, coconut oil and epoxidised derivatives thereof, such as epoxidised soybean oil.

[0067] In some embodiments, the resin comprises a release agent selected from the group consisting of: powdered solids, natural waxes, solid lipids and plant oils. In some embodiments, the powdered solids may be selected from the group consisting of microcrystalline cellulose, talc and kaolin clay. In some embodiments, the natural waxes may be selected from the group consisting of beeswax and carnauba wax. In some embodiments, the solid lipids may be selected from the group consisting of: stearic acid, oleic acid, linoleic acid, palmitic acid, arachidic acid, fatty acid salts, glycerol monostearate and sorbitan monostearate. In some embodiments, the oil may be selected from the group consisting of: sunflower oil, olive oil, canola oil, flax seed oil, grapeseed oil, soybean oil, coconut oil and epoxidised derivatives of sunflower, olive, canola, flax, grapeseed, soybean and coconut oil. In some embodiments, the resin comprises a release agent selected from the group consisting of: microcrystalline cellulose, talc, kaolin clay, beeswax, carnauba wax, stearic acid, oleic acid, linoleic acid, palmitic acid, arachidic acid, fatty acid salts, glycerol monostearate, sorbitan monostearate, sunflower oil, olive oil, canola oil, flax seed oil, grapeseed oil and coconut oil. In some embodiments, the resin comprises a release agent selected from the group consisting of: microcrystalline cellulose, talc, kaolin clay sunflower oil, olive oil, canola oil, flax seed oil, grapeseed oil and coconut oil. In some embodiments, the resin comprises a release agent selected from the group consisting of: microcrystalline cellulose, kaolin clay and sunflower oil. In some embodiments, the resin comprises microcrystalline cellulose. In some embodiments, the resin comprises kaolin clay. In some embodiments, the resin comprises sunflower oil.

[0068] In some embodiments, the resin comprises release agent in an amount from about 1 % to about 100%, from about 1 % to about 90%, from about 1 % to about 80%, from about 1% to about 70%, from about 1% to about 60%, from about 1% to about 50%, from about 1 % to about40%, from about 1% to about 30%, from about 1% to about 20%, from about 1% to about 15%, from about 1% to about 10%, from about 2% to about 15%, from about 3% to about 15%, from about 4% to about 15%, from about 5% to about 15%, from about 6% to about 14%, from about 7% to about 13%, from about 8% to about 12% or from about 9% to about 11% by weight of starch, or any range in between. In some embodiments, the resin comprises release agent in an amount of less than 100, 90, 80, 70, 60, 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1% by weight of starch. In some embodiments, the resin comprises release agent in an amount of greater than 90, 80, 70, 60, 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1% by weight of starch. In some embodiments, the resin comprises release agent in an amount of 100, 90, 80, 70, 60, 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 % by weight of starch. In some embodiments, the resin comprises release agent in an amount of 5, 10, 50 or 100% by weight of starch.

[0069] In one embodiment, the resin comprises an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, sunflower oil and urea. In some embodiments, the resin comprises microcrystalline cellulose in an amount of about 10% by weight of starch. In some embodiments, the resin comprises kaolin clay in an amount of about 5% by weight of starch. In some embodiments, the resin comprises sunflower oil in an amount of about 50% by weight of starch. In some embodiments, the resin comprises urea in a crosslinker: urea ratio of 1 :3 or 1 :5.Resin formulation

[0070] The resin may be prepared by combining the resin ingredients in any suitable way. In one embodiment, the resin is prepared by the steps of: i) dissolving the starch in a solvent, ii) adding plasticiser and crosslinker to the solution, iii) heating and stirring the solution to until a gellike consistency is achieved; and optionally, iv) homogenising the solution. In some embodiments, step i) and step ii) occur simultaneously. In some embodiments, the starch, plasticiser and crosslinker are added sequentially. In some embodiments, the starch, plasticiser and / or crosslinker are only partially dissolved before step iii). Without wishing to be bound by any theory, it is understood that heating the solution facilitates dissolving of the components and ensuring uniform distribution throughout the resin.

[0071] In some embodiments, step iii) comprises heating the mixture to a temperature from about 20°C to about 95°C, from about 30°C to about 95°C, from about 40°C to about 95°C, from about 50°C to about 95°C, from about 60°C to about 95°C, from about 70°C to about 95°C, from about 75°C to about 95°C, from about 75°C to about 85°C or from about 60°C to about 80°C, or any range in between. In one embodiment, step iii) comprises heating the mixture to a temperature from about 60°C to about 80°C. In some embodiments, step iii) comprises heatingthe mixture to a temperature of at least 20, 30, 40, 50, 60, 70, 80, or 90°C. In some embodiments, step iii) comprises heating the mixture to a temperature of less than 30, 40, 50, 60, 70, 80, 90 or 95°C. In some embodiments, step iii) comprises heating the mixture to a temperature of about 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 or 95°C. In some embodiments, step iii) comprises stirring the mixture for at least 1 , 5, 10, 30, 60, 120, 240, 480 or 720 seconds. The stirring may be performed through any suitable means. In one embodiment, the mixture is stirred using a magnetic stirrer, paddle stirrer, blade stirrer, centrifugal stirrer, turbine stirrer, propeller stirrer, anchor stirrer, universal stirrer or using manual stirring.

[0072] In some embodiments, step iv) comprises homogenising the mixture for at least 1 , 5, 10, 30, 60, 120 or 240 seconds. The stirring may be performed through any suitable means. In one embodiment, the mixture is homogenised using an ultrasonic homogeniser, high pressure homogeniser, rotor-stator homogeniser, blender.

[0073] The resin may be in any suitable form. In some embodiments, the resin is a liquid. As used herein, the term "liquid" comprises free-flowing solutions, for example, aqueous solutions. The term "liquid" also comprises viscous liquids, such as a gel. In some embodiments, the resin has a viscosity of less than about 2000, 1000, 900, 800, 700, 600, 500, 400, 300, 200 or 100 centipoise (cP).

[0074] In some embodiments, the resin further comprises a pigment. The pigment may be any suitable color, for example, black, white, red, blue, green, yellow, orange, brown, purple, grey and combinations thereof. In some embodiments, the pigment is a biochar-based black pigment (e.g. BioBlack™ from Nature Coatings). In some embodiments, the pigment is biodegradable.Fiber impregnation

[0075] As used herein, the term “a fiber” refers to a thread or a filament from which textiles are formed. Suitable fibers may be natural fiber or biodegradable synthetic fiber. In one embodiment, the fiber is a plurality of fiber, such as a cloth or sheet. The fiber may be a woven or non-woven fiber. In some embodiments, the fiber is a woven fiber. In some embodiments, the fiber is a non-woven fiber. In some embodiments the fiber is a mixture of woven and non-woven fiber. In some embodiments, the fiber is a natural fiber selected from the group consisting of: jute, hessian, burlap, cotton, hemp, linen, coir, bamboo fiber, sisal, ramie, wool, flax, abaca and bagasse. In some embodiments, the fiber is a mixture of one, two, three, four or more natural fibers. In some embodiments the fiber is jute. In some embodiments the fiber is woven jute. In some embodiments the fiber is a mixture of woven and non-woven jute. Without wishing to be bound by any theory, it is believed that non-woven fibers provide increased rigidity to the packaging material, whereas woven fibers provide less rigidity but greater flexibility. In someembodiments, the fiber is a chopped fiber. The chopped fiber may be of any suitable length. In some embodiments, the chopped fiber has a length of at least 0.1 , 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 2.0, 3.0, 4.0 or 5.0 cm, or any length in between.

[0076] As used herein, the term “impregnated fiber” refers to a fiber in which at least the exterior surface of the fiber has been has substantially coated with the resin after the impregnation step. In one embodiment, in an impregnated fiber is saturated with the resin. As used herein, the term “saturated” means that the fiber is unable to absorb or contain additional resin. As used herein, the term “resin loading” refers to the amount of resin with which the fiber has been impregnated with, as a fraction of the total weight of resin and the fiber (i.e. a 10 g impregnated fiber with a 30 wt% resin loading includes 3 g of resin. Furthermore, an impregnated fiber which comprises resin in an amount of 30% is the same as an impregnated fiber with a 30% resin loading.

[0077] The fiber may be impregnated with the resin through any suitable means. In one embodiment, the fiber is submerged in a resin bath. In another embodiment, the fiber is impregnated by passing the fiber through a resin bath. In one embodiment, the step of passing the fiber through a resin bath comprises submerging the fiber in the resin bath. The fiber may be passed through the resin bath by any suitable means. In some embodiments, the fiber is passed through the resin bath using rollers. In some embodiments, the fiber is impregnated by manually applying the resin to the fiber. In some embodiments, the fiber is impregnated by soaking the fiber in the resin. In some embodiments, the fiber is submerged or soaked in the resin bath for at least 1 , 2, 3, 4, 5, 10, 20, 30, 60, 120, 240 or 480 seconds, or any amount of time in between. In some embodiments, the step of impregnating the fiber includes the step of removing excess resin from the fiber. Excess resin can be removed by any suitable means, for example, by passing a fiber having excess resin through rollers, by scraping the excess resin off manually or by hanging the fiber and allowing the excess resin to drip. In some embodiments, the step of impregnating the fiber with the resin includes the steps of: i) submerging a fiber in a resin bath, and ii) removing excess resin from the fiber.

[0078] In some embodiments, the impregnated fiber comprises the resin in an amount from about 20 wt% to about 75 wt%, from about 30 wt% to about 75 wt%, from about 40 wt% to about 75 wt%, from about 50 wt% to about 75 wt%, from about 55 wt% to about 70 wt% or from about 60 wt% to about 70 wt%, or any range in between. In some embodiments, the impregnated fiber comprises the resin in an amount of at least 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, or 70 wt%. In some embodiments, the impregnated fiber comprises resin in an amount of less than 25, 30, 35, 40, 45, 50, 55, 60, 65, 70 or 75 wt%. In some embodiments, the impregnated fiber comprises resin in an amount of about 20, 25, 30, 35, 40, 45, 50, 51 , 52, 53, 54, 55, 56, 57, 58, 59, 60, 61 , 62, 63, 64, 65, 66, 67, 68, 69, 70 or 75 wt%. In some embodiments, the impregnated fibercomprises resin in an amount of about 60, 61, 62, 63, 64, 65, 66, 67, 68, 69 or 70 wt%. In some embodiments, the impregnated fiber comprises resin in an amount of about 65 wt%. It will be appreciated that the preceding amounts refer to the impregnated fiber at the end of the impregnation step, after any excess resin has been removed.

[0079] Without wishing to be bound by any theory, it is understood that the resin loading has a significant impact on the mechanical properties of the packaging material. Insufficient resin loading (i.e. below 20 wt%) may result in materials which lack structural rigidity and fail to hold their moulded shape, or materials where the resin does not adequately impregnate the fibers, resulting in poor cohesion and reduced durability. Conversely, a resin loading which is too high, (i.e. above 75%) can result in a range of complications, such as:• Flexibility Loss: Excess resin stiffens the fibers excessively, making it unsuitable for applications requiring shock absorption or flexibility.• Material Waste: Overuse of resin unnecessarily increases production costs and wastes starch, which is a key resource.• Surface defects: Excess resin creates starch films on the surface of the packaging material.• Cosmetic Defects: The surface of the packaging material appears uneven, detracting from the product’s visual appeal.• Decreased Water Stability: The exposed starch film absorbs water easily, undermining the moisture resistance of the packaging material.• Stickiness: The packaging material feels tacky to the touch when moist, reducing its usability and perceived quality.Curing

[0080] As used herein, the term “curing” refers to the step of heating impregnated fiber to simultaneously remove water and to react the resin components. The curing step may be performed through a variety of techniques, provided it achieves sufficient temperature to remove the water and cause the resin components (e.g. the crosslinker, starch and plasticiser) to react. For example, the curing may be performed using oven drying, or by compression moulding the impregnated fiber. The step of curing may comprise locating the impregnated fiber on or in a mould.

[0081] In some embodiments when oven drying is used, the curing step may comprise the steps of i) heating the impregnated fiber in a mould at a first temperature to form a shaped fiber, and ii) heating the shaped fiber at a second temperature to thereby form the packaging material. In some embodiments, the shaped fiber is removed from the mould before heating at the second temperature. In some embodiments, the shaped fiber is heated in the mould at the second temperature. In some embodiments, the first temperature is from about 60°C to about 100°C, or from about 70°C to about 90°C. In some embodiments, the first temperature is at least 60, 70, 80 or 90°C. In some embodiments, the first temperature is about 60, 70, 80, 90 or 100°C. In some embodiments, the second temperature is from about 100°C to about 180°C, from about 110°C to about 170°C, from about 120°C to about 160°C or from about 130°C to about 150°C. In some embodiments, the second temperature is at least 100, 110, 120, 130, 140, 150, 160 or 170°C. In some embodiments, the second temperature is less than 110, 120, 130, 140, 150, 160, 170 or 180°C. In some embodiments, the first temperature is 80°C. In some embodiments, the second temperature is from 130°C to 150°C. In some embodiments, the impregnated fiber is heated at the first temperature for at least 10, 20, 30, 45, 60, 90, 120 or 240 minutes, or any time in between. In some embodiments, the impregnated fiber is heated at the first temperature for less than 20, 30, 45, 60, 90, 120 or 240 minutes, or any time in between. In some embodiments, the impregnated fiber is heated at the first temperature for 60 minutes. In some embodiments, the shaped fiber is heated at the second temperature for from 30 to 240 minutes, or from 30 to 180 minutes, 60 to 180 minutes, or any range in between. In some embodiments, the shaped fiber is heated at the second temperature for at least 10, 20, 30, 45, 60, 90, 120, 180 or 240 minutes, or any time in between. In some embodiments, the impregnated fiber is heated at the first temperature for less than 20, 30, 45, 60, 90, 120, 180 or 240 minutes, or any time in between.

[0082] In some embodiments, the curing is performed using compression moulding. Compression moulding (also referred to as “hot pressing”) refers to a process where a moulding material (i.e. the impregnated fiber) is placed into a moulding cavity which has a predetermined shape and is subjected to pressure and heat. The moulding cavity is generally pre-heated to the required temperature, and is maintained at a particular temperature throughout the process. Once the moulding material is positioned in the moulding cavity, the mould is closed and pressure is applied to the moulding material, causing it to conform to the shape defined by the moulding cavity. In some embodiments, the pressure and / or temperature are maintained until the moulding material has partially cured. In preferred embodiments, the pressure and / or temperature are maintained until the moulding material has substantially cured. In preferred embodiments, the pressure and / or temperature are maintained until the moulding material has completely cured.

[0083] The impregnated fiber may be arranged with the weave aligned in-plane with the principal axes of the mould, perpendicular to the principle axis of the mould, or at any angle inbetween (a bias) (e.g. at a diagonal orientation) prior to compression moulding. Without wishing to be bound by any theory, it is believed that a diagonal orientation allows the yarns of the fiber to shear and rotate more readily under load, distributing strain through in-plane shear rather than tensile stretching, which reduces local stress concentrations as well as wrinkling and tearing during deep draws.

[0084] In some embodiments, the method comprises the step of stacking a plurality of impregnated fibers prior to curing, for example, two, three or four impregnated fibers. The impregnated fibers may be the same or different with respect to the resin loading percentage and / or resin composition. Without wishing to be bound by any theory, it is believed that increasing the thickness of the material and fiber content in this manner improves the bending stiffness and strength of the resulting packaging material (e.g. by approximately double for when the two impregnated fibers are stacked prior to curing), enabling more rigid inserts for heavier or more fragile products. In some embodiments, the plurality of fibers are arranged with the weave of each fiber aligned with respect to the principal axis of the mould. In some embodiments, the weave of each fiber is aligned with respect to the principal axis of the mould. In some embodiments, the weave of one or more fibers is not aligned with respect to the principal axis of the mould.

[0085] In conventional compression moulding methods, the mould cavity is generally coated with a silicone-based lubricating coating (e.g. Teflon® / polytetrafluoroethylene (PTFE)), which facilitates release of the cured material from the mould and prevents sticking. However, use of a lubricating coating can slow production times and are expensive, toxic, and can leave residue on the packaging material which may compromise its compostability.

[0086] In conventional methods, compressing and heating a starch resin in a mould which does not have a lubricating coating would typically result in significant adhesion between the resin and the surface of the moulding cavity, thereby causing deleterious effects on the packaging material, such as burning, tearing and surface defects. In view of this consideration, conventional methods are led towards lower temperatures in addition to using lubricating coatings, in order to avoid adhesion, as excessive heat often exacerbates adhesion in polymeric systems. In contrast, some embodiments of the present invention enable production of packaging materials through compression moulding without using any lubricating coating on the moulding cavities.

[0087] Without wishing to be bound by any theory, it is believed that using high curing temperatures may create a flash-dried surface on the resin, thereby forming a solid interface that reduces adhesion and allows clean release of the packaging material. This advantageously may allow for drastically reduced processing times compared to oven drying at lower temperatures, and the flash-dried surface improves the packaging materials finish, eliminating sticking-induced defects. In some embodiments, the compression moulding apparatus does not comprise alubricating coating on the portions of the apparatus which contact the impregnated resin. In some embodiments, the compression moulding is performed using moulding cavities which do not comprise a lubricating coating.

[0088] The mould may made from any suitable material. In some embodiments, the mould is made from polylactic acid filament, wood, metal, aluminium, steel or ceramics. In some embodiments, the mould is made using 3D printing. In some embodiments, the mould is made from aluminium.

[0089] In some embodiments, the mould geometry is a substantially flat, wall-less insert with a shaped top surface. In some embodiments, the mould geometry is a curved-wall insert in which four curved walls extend from the top surface to the base. Without wishing to be bound by any theory, it is understood that curved-wall inserts provide increased sidewall strength and crush resistance, and are particularly suitable for small or more localised packaging applications.

[0090] In some embodiments when compression moulding is used, curing the impregnated fiber comprises the steps of i) placing the impregnated fiber into the mould cavity, ii) closing the mould cavity and applying pressure to the impregnated fiber, and iii) releasing the cured impregnated fiber from the mould cavity to thereby form the packaging material. In one embodiment, the compression moulding comprises use of a hydraulic heat press. Advantageously, the inventor has found that a hydraulic heat press provides controlled and repeatable pressure and temperature, thereby increasing throughput and yielding cleaner, more dimensionally consistent packaging parts.

[0091] When compression moulding is used, the curing may be performed at any suitable curing temperature. In some embodiments the curing is performed at a temperature from about 100°C to about 400°C, from about 125°C to about 375°C, from about 150°C to about 350°C, from about 175°C to about 350°C, from about 200°C to about 350°C, from about 225°C to about 350°C, from about 250°C to about 350°C, from about 275°C to about 350°C, or from about 300°C to about 350°C, or any range in between. In some embodiments, the curing is performed at a temperature of above 100, 125, 150, 175, 200, 225, 250, 275, 300, 325, 350 or 375°C. In some embodiments, the curing is performed at a temperature below 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, 375 or 400°C. In some embodiments, the curing is performed at a temperature of about 100, 125, 150, 175, 200, 225, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350, 375 or 400°C or any temperature in between. In one embodiment, the curing is performed at a temperature of about 290, 300, 310, 320, 330, 340 or 350°C. In one embodiment, the curing is performed at a temperature of about 310°C.

[0092] When compression moulding is used, the curing may be performed for any suitable amount of time. It will be appreciated that the curing time is related to the curing temperature, with lower temperatures requiring a longer curing time. It will be understood that the curing time refers to the amount of time in which pressure is applied to the impregnated fiber. In preferred embodiments, the time between contacting the impregnated fiber with the mould cavity and applying pressure to the impregnated fiber is less than 60, 50, 40, 30, 20, 10, 5, 4, 3, 2 or 1 second(s). In some embodiments, the curing time is from 1 second to 10 minutes, from 1 second to 9 minutes, from 1 second to 8 minutes, from 1 second to 7 minutes, from 1 second to 6 minutes, from 1 second to 5 minutes, from 1 second to 4 minutes, from 1 second to 3 minutes, from 1 second to 2 minutes, from 1 second to 1 minute, from 1 second to 50 seconds, from 1 second to 40 seconds, from 1 second to 30 seconds, from 1 second to 20 seconds, from 1 second to 15 seconds, from 1 second to 10 seconds, from 1 second to 5 seconds, from 3 second to 10 seconds or from 3 seconds to 5 seconds, or any range in between. In some embodiments, the curing time is less than 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 minute(s), or less than 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, or 2 seconds. In some embodiments, the curing time is at least 9, 8, 7, 6, 5, 4, 3, 2, or 1 minute(s), or at least 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 seconds. In some embodiments, the curing time is about 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 minute(s), or about 50, 40, 30, 20, 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5, 4, 3, 2 or 1 second(s). In some embodiments, the curing time is about 15, 14, 13, 12, 11 , 10, 9, 8, 7, 6, 5 or 4 seconds. In some embodiments, the curing time is about 10 seconds.

[0093] In some embodiments, the packaging material produced according to the present methods is biodegradable. As used herein, the term “biodegradable” is understood to refer to materials which may be decomposed through natural biological processes. Without wishing to be bound by any theory, it is understood that biodegradable materials may still leave behind toxic components after degradation, such as microplastics. In some embodiments, the packaging material produced according to the present methods is compostable. As used herein, the term “compostable” is understood to refer to materials which are primarily made from carbon-based components and which readily decomposed through natural biological processes without leaving toxic or environmentally damaging components behind (e.g. microplastics, heavy metals).DEFINITIONS

[0094] In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set out below. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only and is not intended to be limiting.

[0095] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one having ordinary skill in the art to which the invention pertains.

[0096] Unless the context clearly requires otherwise, throughout the description and the claims, the terms “comprise”, “'comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. For example, a composition, mixture, process or method that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, mixture, process or method.

[0097] The transitional phrase "consisting of’ excludes any element, step, or ingredient not specified. If in the claim, such would close the claim to the inclusion of materials other than those recited except for impurities ordinarily associated therewith. When the phrase "consisting of' appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole.

[0098] The transitional phrase "consisting essentially of" is used to define a composition, process or method that includes materials, steps, features, components, or elements, in addition to those literally disclosed, provided that these additional materials, steps, features, components, or elements do not materially affect the basic and novel characteristic(s) of the claimed invention. The term "consisting essentially of' occupies a middle ground between "comprising" and "consisting of".

[0099] Where the applicant has defined an invention or a portion thereof with an open-ended term such as "comprising", it should be readily understood that (unless otherwise stated) the description should be interpreted to also describe such an invention using the terms "consisting essentially of" or "consisting of." In other words, with respect to the terms “comprising”, “consisting of”, and “consisting essentially of’, where one of these three terms is used herein, the presently disclosed and claimed subject matter may include the use of either of the other two terms. Thus, in some embodiments not otherwise explicitly recited, any instance of “comprising” may be replaced by “consisting of” or, alternatively, by “consisting essentially of”.[000100] While reference may be made in this disclosure to the invention comprising a combination of a plurality of elements, it is also understood that this invention is regarded to comprise combinations which omit or exclude one or more of such elements, even if this omission or exclusion of an element or elements is not expressly stated herein, unless it is expressly stated herein that an element is essential to the applicant' s combination and cannot be omitted. It isfurther understood that the related prior art may include elements from which this invention may be distinguished by negative claim limitations, even without any express statement of such negative limitations herein. It is to be understood, between the positive statements of applicant's invention expressly stated herein, and the prior art and knowledge of the prior art by those of ordinary skill which is incorporated herein even if not expressly reproduced here for reasons of economy, that any and all such negative claim limitations supported by the prior art are also considered to be within the scope of this disclosure and its associated claims, even absent any express statement herein about any particular negative claim limitations.[000101] As used herein, with reference to numbers in a range of numerals, the terms "about," "approximately" and "substantially" are understood to refer to the range of -10% to +10% of the referenced number, preferably -5% to +5% of the referenced number, more preferably -1 % to + 1 % of the referenced number, most preferably -0 .1 % to +0 .1 % of the referenced number. Moreover, with reference to numerical ranges, these terms should be construed as providing support for a claim directed to any number or subset of numbers in that range. For example, a disclosure of from 1 to 10 should be construed as supporting a range of from 1 to 8, from 3 to 7, from 1 to 9, from 3.6 to 4.6, from 3.5 to 9.9, from 8 to 10, and so forth.[000102] As used herein, with reference to qualitative values, the term "substantially" is understood to mean at least 50%, preferably at least 80%, more preferably at least 90%, more preferably at least 95%. For example, the phrase “the article is substantially coated in resin” is understood to mean that at least 50%, preferably at least 80%, more preferably at least 90%, more preferably at least 95% of the article is coated in resin.[000103] The terms “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.[000104] Unless expressly stated to the contrary, "or" refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).[000105] The term "and / or" used in the context of "X and / or Y" should be interpreted as "X," or "Y," or "X and Y." Similarly, "at least one of X or Y" should be interpreted as "X," or "Y," or "both X and Y."[000106] The indefinite articles "a" and "an" preceding an element or component of the invention are intended to be non-restrictive regarding the number of instances (i.e., occurrences) of the element or component. Therefore "a" or "an" should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.[000107] As used herein, wt.% refers to the weight of a particular component relative to total weight of the referenced composition.[000108] Various features of the embodiments of the invention disclosed herein are, for brevity, described in the context of a single embodiment, but may also be provided separately or in any suitable sub-combination. All combinations of the embodiments are specifically embraced by the illustrative embodiments disclosed herein just as if each and every combination was individually and explicitly disclosed. In addition, all sub-combinations listed in the embodiments describing such variables are also specifically embraced by the present compositions and are disclosed herein just as if each and every such sub-combination was individually and explicitly disclosed herein.[000109] In the foregoing paragraphs, where various ratios of components have been disclosed. It will be appreciated that these ratios of components can be combined in any disclosed combination.DETAILED DESCRIPTION[000110] The skilled addressee will understand that the invention comprises the embodiments and features disclosed herein as well as all combinations and / or permutations of the disclosed embodiments and features.[000111] The present invention will now be described with reference to the following examples which should be considered in all respects as illustrative and non-restrictive.Generic method for preparation of packaging material using compression moulding[000112] This example details general conditions for formation of a packaging material by impregnating a fiber with a starch-based resin and curing using compression moulding.[000113] A. Preparation of starch resinA starch resin was prepared by dissolving starch in water at a concentration of 5-15%. Plasticiser (0.5-9% by mass of starch) and crosslinker (1-20% by mass of starch) were added, and the mixture was heated at a temperature from about 60°C to about 80°C and stirred toT1achieve a homogeneous gel-like consistency. The mixture was then blended for approximately 1 minute to ensure thorough homogenization.[000114] B. Impregnation of fiberSections of fiber were soaked in the prepared starch resin to form an impregnated fiber with a resin loading from 20 to 75%. Excess resin was removed to ensure a uniform coating.[000115] C. Curing using compression mouldingThe impregnated fiber was placed in a two-part mould in a compression moulding apparatus, which had been pre-heated to between 250-350°C. Pressure was applied to the compression moulding apparatus for from 3-10 seconds, thereby forming the packaging material.Generic method for preparation of packaging material using oven drying[000116] This example details general conditions for formation of a packaging material by impregnating a fiber with a starch-based resin and curing using oven drying.[000117] A. Preparation of starch resinA starch resin was prepared by dissolving starch in water at a concentration of 5-15%. Plasticiser (0.5-9% by mass of starch) and crosslinker (1-20% by mass of starch) were added, and the mixture was heated at a temperature from about 60°C to about 80°C and stirred to achieve a homogeneous gel-like consistency. The mixture was then blended for approximately 1 minute to ensure thorough homogenization.[000118] B. Impregnation of fiberSections of fiber were soaked in the prepared starch resin to form an impregnated fiber with a resin loading from 20 to 75%. Excess resin was removed to ensure a uniform coating.[000119] C. Curing using oven dryingThe impregnated fiber was placed into a two-part mould and dried in an oven at 60-100°C for approximately 1 hour, or until the impregnated fiber achieved sufficient rigidity to hold its shape. It is understood that this initial drying step removes water and allows the mould to hold its shape without compression moulding. The shaped impregnated fiber is then removed from the two-part mould and cured in the oven at a temperature from 130°C to 150°C for from 1 -3 hours, thereby forming the packaging material.[000120] EXAMPLE 1 - Resin Loading Percentage[000121] This example shows the effect that varying the resin load of the impregnated fiber has on the packaging material properties.[000122] Procedure:1. A resin was formulated with starch (10 wt%), citric acid (10% by weight of starch), glycerol (3% by weight of starch), and water.2. Woven jute sheets were cut to dimensions of 30 cm x 30 cm.3. The resin was applied to the jute sheets via immersion, and excess resin was removed using rollers to achieve resin loadings of 10%, 65%, and 80% (relative to the total mass of the impregnated fiber sheets).4. The impregnated sheets were cured using compression moulding at 310°C for 10 seconds under minimal pressure.[000123] Results:[000124] 10% resin: The packaging material exhibited insufficient mechanical strength and rigidity. It failed to maintain its moulded shape and was prone to deformation under load.[000125] 65% resin: The packaging material demonstrated optimal tensile strength, rigidity, and flexibility, with a smooth surface finish and excellent water resistance.[000126] 80% resin: The packaging material was overly stiff, with reduced resilience. Excess resin resulted in higher production costs and surface irregularities.[000127] EXAMPLE 2 - Crosslinker Percentage[000128] This example demonstrates the effect of varying the crosslinker concentration on packaging material properties, weight of starch).[000129] Procedure:1. Five resins were prepared using starch (10 wt%), glycerol (3 wt% by weight of starch), and varying citric acid (CA) concentrations (0%, 5%, 10%, 20%, and 50% by weight of starch) in water.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. The impregnated sheets were cured using compression moulding at 310°C for 10 seconds.4. Post-curing, the packaging materials were subjected to tensile strength tests, water resistance assessments, and visual inspection.[000130] Results:[000131] 0% CA: The packaging material exhibited poor rigidity and resilience, with inadequate mechanical properties.[000132] 5% CA: Moderate rigidity, tensile strength was lower than higher CA concentrations.[000133] 10% CA: Superior rigidity and tensile strength. Minimal absorption during immersion.[000134] 20% and 50% CA: Comparable tensile strength to 10% CA resin, but reduced flexibility and increased brittleness.[000135] EXAMPLE 3 - Plasticiser Percentage[000136] This example demonstrates the effect of varying the plasticiser concentration on packaging material properties.[000137] Procedure:1. Four resins were prepared using starch (10 wt%), citric acid (10% by weight of starch), and varying glycerol concentrations (1%, 3%, 5%, and 10% by weight of starch) in water.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at 310°C for 10 seconds.4. Flexibility and shape retention were assessed through bending and tensile strength tests.[000138] Results:[000139] 1% glycerol: Packaging material was rigid, with excellent tensile strength and shape retention. Flexibility was minimal.[000140] 3% glycerol: Balanced flexibility and rigidity.[000141] 5% glycerol: Increased flexibility but slightly reduced rigidity.[000142] 10% glycerol: Significant flexibility, the packaging material exhibited deformation under its own weight.[000143] EXAMPLE 4 - Microcrystalline Cellulose (MCC) additive[000144] This example demonstrates the effect of including microcrystalline cellulose (MCC) as a resin additive on packaging material properties.[000145] Procedure:1. Three resins were prepared using starch (10 wt%), citric acid (10% by weight of starch), glycerol (3% by weight of starch), and varying MCC concentrations (0%, 10%, and 15% by weight of starch) in water.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at 310°C for 10 seconds. The compression moulding apparatus did not comprise a lubricating coating on the portions of the apparatus which contact the impregnated resin.4. Mould release and surface quality were evaluated post-curing.[000146] Results:[000147] 0% MCC: Complete drying and adequate release of the packaging material from the mould. However, some sticking occurred during curing, causing tearing and surface defects.[000148] 10% MCC: Mould release was smooth, with no sticking or tearing. Surface quality was excellent.[000149] 15% MCC: Mould release was effective. Packaging material exhibited a powdery residue on the surface, reducing visual appeal.[000150] EXAMPLE 5 - Oil Additives[000151] This example demonstrates the effect of including sunflower oil as a resin additive on packaging material properties.[000152] Procedure:1. Three resins were prepared using starch (10%), citric acid (10%), glycerol (3%), and varying sunflower oil concentrations (0%, 50%, and 100% by weight of starch) in water. Sunflower oil was added during the final homogenisation step outlined in part A of Example 1.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at 310°C for 10 seconds. The compression moulding apparatus did not comprise a lubricating coating on the portions of the apparatus which contact the impregnated resin.4. The resins were evaluated for homogenization difficulty, processability during impregnation, sticking during step 3, and surface quality of the final packaging material.[000153] Results:[000154] 0% oil: Resin was easy to mix and apply but caused some sticking during curing, resulting in tearing and surface defects.[000155] 50% oil: Resin was easy to homogenize and apply. Sticking resistance improved significantly, and surface defects were minimal. Flexibility increased slightly, but rigidity remained acceptable.[000156] 100% oil: Homogenization required prolonged mixing, complicating resin preparation. No sticking occurred during curing, increased flexibility reduced the packaging material’s rigidity.[000157] EXAMPLE 6 - Kaolin Clay Additive[000158] This example demonstrates the effect of including kaolin clay as a resin additive on packaging material properties.[000159] Kaolin concentrations of 0%, 5%, and 10% (by weight of starch) were tested.[000160] Procedure:1. Three resins were prepared using starch (10%), citric acid (10%), glycerol (3%), and varying kaolin clay concentrations (0%, 5%, and 10% by weight of starch) in water.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at 310°C for 10 seconds. The compression moulding apparatus did not comprise a lubricating coating on the portions of the apparatus which contact the impregnated resin.4. Mould release and mechanical properties were evaluated.[000161] Results:[000162] 0% kaolin: Complete drying and adequate release of the packaging material from the mould. However, some sticking during curing, with relatively poor thermal and mechanical properties compared to materials including kaolin clay.[000163] 5% kaolin: Excellent mould release, smooth surface quality, and improved thermal resistance compared to packaging materials without kaolin.[000164] 10% kaolin: Comparable results to 5% kaolin, slightly increased brittleness.[000165] EXAMPLE 7 - Retrogradation inhibitor additive[000166] This example demonstrates the effect of including urea as a resin additive on packaging material properties.[000167] Procedure:1. Two resins were prepared using starch (10%), citric acid (10%), and varying urea concentrations (in a molar ratio of CA:urea of 1 :3 and 1 :5) in water.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at 310°C for 10 seconds. The compression moulding apparatus did not comprise a lubricating coating on the portions of the apparatus which contact the impregnated resin.4. The packaging material was tested for tensile strength, flexibility, and water resistance.[000168] Results:[000169] 1 :3 CA:urea: Improved mechanical strength with no significant changes in flexibility compared to packaging materials which do not include urea.[000170] 1 :5 CA:urea: Slight increase in rigidity compared to 1 :3 CA:urea.[000171] EXAMPLE 8 - Fiber Type[000172] This example demonstrates the effect of varying the fiber format (chopped or woven) on packaging material properties.[000173] Procedure:1 . Two resins were prepared using starch (10%), citric acid (10%) and glycerol (3%) in water.2. Resin was impregnated into woven and nonwoven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at 310°C for 10 seconds. The compression moulding apparatus did not comprise a lubricating coating on the portions of the apparatus which contact the impregnated resin.4. Mechanical strength and flexibility were evaluated.[000174] Results:[000175] Woven fibers: Balanced flexibility and tensile strength.[000176] Non-woven fibers: Increased rigidity and tensile strength.[000177] EXAMPLE 9 - Curing Parameters[000178] This example demonstrates the effect of compression moulding curing temperature on packaging material properties.[000179] Procedure:1. Seven resins were prepared using starch (10%), citric acid (10%) and glycerol (3%) in water.2. Resin was impregnated into woven jute sheets, achieving a resin loading of 65%.3. Sheets were cured using compression moulding at varying temperatures (100°C, 150°C, 200°C, 250°C, 310°C, 350°C and 400°C) for 10 seconds. The compression moulding apparatus did not comprise a lubricating coating on the portions of the apparatus which contact the impregnated resin.4. The packaging materials were inspected for drying efficiency, sticking, and mechanical properties.[000180] Results:[000181] 100°C and 150°C: Insufficient drying caused severe sticking and weak mechanical properties. Removal of material, ripped sheets.[000182] 200°C: Improved drying but sticking persisted, causing surface defects. Removal of material, ripped sheets.[000183] 250°C: Partial sticking occurred, but surface quality and mechanical properties improved. Removal of material, defected sheets.[000184] 310°C: Complete drying and improved release of the packaging material from the mould. Improved surface quality and mechanical properties compared to lower temperatures.[000185] 350°C: Complete drying and improved release. Surface quality slightly reduced due to charring and mechanical properties were weakened.[000186] 400°C: Dry sheets resulted in 4 seconds. Additional time resulted in burning.[000187] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms, and in particular features of any one of the various described examples may be provided in any combination in any of the other described examples. Various modifications and alterations to this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that this invention is not intended to be unduly limited by the illustrative embodiments and examples set forth herein and that such examples and embodiments are presented by way of example only with the scope of the invention intended to be limited only by the claims set forth herein as follows.

Claims

CLAIMS1 . A method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises the resin in an amount of 20-75 wt%; and b) curing said impregnated fiber to thereby produce said packaging material; wherein the resin comprises:• about 5-15 wt% starch or a starch derivative,• about 1-20 wt% crosslinker by weight of starch,• about 0.5-9 wt% plasticiser by weight of starch, and• about 80-94 wt% solvent.

2. The method of claim 1 , wherein the crosslinker is selected from the group consisting of: citric acid, maleic anhydride, succinic acid and tartaric acid.

3. The method of claim 1 or claim 2, wherein the plasticiser is selected from the group consisting of: glycerol, sorbitol, mannitol xylitol, polyethylene glycol (PEG), urea, fructose, sucrose, oxidised sucrose and formamide.

4. The method of any one of claims 1 to 3, wherein the solvent is water.

5. The method of claim 1 , wherein the resin comprises:• about 5- 15 wt% starch ,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch, and• about 80-94 wt% water.

6. The method of any one of claims 1 to 5, wherein the resin further comprises an auxiliary agent selected from the group consisting of: microcrystalline cellulose, talc, kaolin clay, beeswax, carnauba wax, stearic acid, fatty acid salts, glycerol monostearate, urea, vegetable oils and epoxidised vegetable oils.

7. The method of any one of claims 1 to 5, wherein the resin further comprises an auxiliary agent selected from the group consisting of: microcrystalline cellulose, kaolin clay, urea and sunflower oil8. The method of claim 1 , wherein the resin comprises two or more crosslinkers.

9. The method of claim 1 , wherein the resin comprises two or more plasticisers.

10. The method of claim 1 , wherein the resin comprises two or more solvents.

11. The method of any one of claims 1 to 10, wherein the fiber is a natural fiber selected from the group consisting of: jute, hessian, burlap, cotton, hemp, linen, coir, bamboo fiber, sisal, ramie, wool, flax, abaca and bagasse.

12. The method of any one of claims 1 to 10, wherein the fiber is a woven fiber13. The method of any one of claims 1 to 10, wherein the fiber is woven jute fiber.

14. The method of any one of claims 1 to 10, wherein the impregnated fiber comprises the resin in an amount of about 65 wt%.

15. The method of any one of claims 1 to 14, wherein the curing is performed by oven drying or by compression moulding.

16. The method of any one of claims 1 to 14, wherein the curing is performed at a temperature from about 100°C to about 400°C.

17. The method of any one of claims 1 to 14, wherein the curing is performed at a temperature from about 300°C to about 350°C.

18. A method of preparing a packaging material, the method comprising the steps of: a) impregnating a fiber with a resin to form an impregnated fiber, wherein the impregnated fiber comprises resin in an amount of 20-75 wt%; and b) compression moulding said impregnated fiber at a temperature from about 300°C to about 350°C to thereby produce said packaging material; wherein the resin comprises:• 5-15 wt% starch,• about 1-20 wt% citric acid by weight of starch,• about 0.5-9 wt% glycerol by weight of starch,• about 80-94 wt% water.

19. The method of any one of claims 1 to 18, wherein the packaging material is compostable.

20. A packaging material produced according to the method of any one of claims 1-18.

21. Use of the packaging material of claim 20 in a package.