EP4665786A1

EP4665786A1 - A package material and a method for making such material

Info

Publication number: EP4665786A1
Application number: EP24706683.0A
Authority: EP
Inventors: Lars Sandberg; Anna Svedberg; Sara WALLSTÉN; Jan Nordin
Original assignee: Nouryon Chemicals International BV; Cellofibers Sweden AB
Current assignee: Nouryon Chemicals International BV; Cellofibers Sweden AB
Priority date: 2023-02-17
Filing date: 2024-02-16
Publication date: 2025-12-24
Also published as: WO2024170766A1; JP2026506977A; CN120917088A; KR20250149178A; CL2025002475A1

Abstract

The present invention relates to an expandable granule comprising lignocellulosic material and one or more expandable particles and/or pre-expanded particles, and optionally light weight particles, optionally also containing one or more binding agents, wherein the expandable granule has a bulk density from about 0.05 to about 0.8 g/cm³, the expandable granule being suitable for use in a package. The present further relates to a method for manufacture of said granule and the use of said granule e.g. in package applications.

Description

A PACKAGE MATERIAL AND A METHOD FOR MAKING SUCH MATERIAL

Field of the invention

The present invention relates to a granule suitable for use in a package, a method for its manufacture and use of said granule e.g. in package applications.

Background

The application and manufacture of expanded polystyrene (EPS) or expanded polypropylene (EPP) for use in packages have previously been described. However, these foamed and/or molded packages are still based upon raw material emanating from fossil resources, e.g. oil.

Further, EPS may be used as wrapping and/or as package material, and also in disposable products such as disposable cups. The production of EPS yearly embraces millions of tonnes worldwide, and about 60 % thereof is used in packages and disposable products. Only a fraction of said products are recycled and some even estimate that some landfills may comprise from 25 - 35 wt.% of EPS.

Through EP 0752444 A1 there is described a moldable pulp material useful for the production of environmentally friendly shock absorbing packaging for electric appliances as a substitute for polystyrene foam packaging. In the method, 1 to 5 weight % thermally expandable hollow particles are mixed with a pulp and a starch binder in water. The mixture is filled into a mold assembly and compressed and heated to produce a molded pulp product.

Through WO 0154988 A2 there is described a low-density paperboard article useful as insulated container which does not use EPS. The method includes providing a papermaking furnish containing cellulosic fibers, and from about 0.25 to about 10 % by weight dry basis expandable microspheres, preferably from about 5 to about 7 wt. %, and forming a paperboard web from the papermaking furnish on a papermaking machine. The density is mentioned to be 6.0 to about 10 lb/3MSF/mil.

There is thus a need for material useful in packages that are minimizing the usage of fossil resources for their raw material, recyclable, at the same time also providing an easy to handle and moldable material, and at the same time providing a reasonable density such as a density from about 0.05 to about 0.8 g/cm³. Summary of the invention

The present invention solves/alleviates one or more of the above problems by providing according to a first aspect an expandable granule comprising lignocellulosic material and one or more expandable particles and/or pre-expanded particles, and optionally light weight particles, optionally also containing one or more binding agents, wherein the expandable granule has a bulk density from about 0.05 to about 0.8 g/cm³ preferably about 0.1 to about 0.8 g/cm³. Said expandable granule may comprise biopolymeric materials (including lignocellulosic material) in an amount of at least 95 wt.%.

The present invention also provides according to second aspect a process for manufacturing an expandable granule comprising the following steps: a) providing lignocellulosic material, preferably cellulosic fibers, and b) providing expandable particles and/or light weight particles, and mixing said lignocellulosic material with said particles, preferably involving an additional step of adding a binding agent, thus providing a granule.

The present invention also provides according to a third aspect a granule obtainable by a process according to the second aspect.

The present invention also provides according to a fourth aspect a use of a granule according to the first or third aspect in the manufacturing of a foamed material, such as a chock absorbing material, or in an insulation material for building constructions or in an isolation material for keeping warm or cold food or food ingredients, such as an environmentally friendly shock absorbing packaging material recyclable with paper board.

The present invention also provides according to a fifth aspect a method for manufacturing of a foamed product, preferably comprising less than about 5 % of a fossil-based polymer, comprising the following steps: i) providing one or more granules according to the first aspect, or obtained by a process according to the second aspect, or one or more granules according to the third aspect, ii) filling said granules into a mold assembly and heating said material, preferably to from about 50 to about 150 °C, more preferably to from about 50 to about 120 °C, most preferred to from about 60 to about 100 °C, thus providing an expanded foamed product. The heating may further e.g. be done in in an oven or in an autoclave, or a combination thereof.

The present invention also provides according to a sixth aspect a foamed product obtainable by a process according to the fifth aspect.

Brief description of the figures

Fig. 1 a) shows a test regarding short fibers (birch fibers) for preparing the expandable granule of the present invention.

Fig. 1 b) shows a test regarding long fibers (pine fibers) for preparing the expandable granule of the present invention.

Fig. 1c) shows expandable granules of the present invention prepared by using different fiber types in a fill test; birch in Fig. 1 d ), eucalyptus in Fig. 1c2), and pine in Fig. 1c3).

Fig. 1d) shows expandable granules comprising different types of binding agents.

Fig. 1 e) shows pictures of the expandable granules of the present invention before and after different Laboratory pulp refiner (PFI)-m illing treatments.

Fig 1 f) shows how a scheme how to prepare expandable granules by combining wet wood fiber flakes with expandable microspheres and optionally a binding agent (“binder”).

Fig. 2a) shows a schematic picture and Fig. 2b) shows a microscopy picture of a preferred embodiment of the expandable granule of the present invention.

Fig. 3a) shows a picture of granulation of expandable granules in a high-shear mixer.

Fig. 3b) shows a picture of drying the expandable granules after granulation in a fluid bed dryer.

Fig. 3c) shows a picture of filling the expandable granules in a mold before putting the filled mold into an oven.

Fig. 3d) shows a picture of the the molded material after treatment in an oven for 15 min.

Fig. 3e) shows the product obtained when casting the material in a different, i.e. cylindrical, mold.

Fig. 4a) shows the application of the expandable granule of the present application in full scale application.

Fig. 4b) shows the release of the molded (and expanded) product in full scale test from mold.

Fig. 5a) shows a molded product made from expandable granules of the present invention, wherein the expandable granules comprise recycled fibers.

Fig. 5b) and Fig. 5c) show molded products made from expandable granules of the present invention, wherein the expandable granules comprise rejected fibers. Detailed description of the invention

The present invention provides according to a first aspect an expandable granule comprising lignocellulosic material and one or more expandable particles, and/or pre-expanded particles, and optionally other light weight particles, optionally also containing one or more binding agents, wherein the expandable granule having has a bulk density from about 0.05 to about 0.8 g/cm³ preferably about 0.1 to about 0.8 g/cm³, preferably wherein fossil based polymers are present in an amount of below 5 wt%.

It has unexpectedly been found that such expandable granule is suitable for the manufacture of foamable and foamed products, such as chock absorbing material or insulation material, for instance for building constructions or for keeping warm or cold food or food ingredients. A quantity of the expandable granules can be put into a mold, which may have any sensible form, and be molded together by application of heat so to form a molded product. During the heat application, the expandable granules expand and, at the same time mold together. Due to its content of lignocellulosic material, the obtained product is after use recyclable together with paper board. Said lignocellulosic material is further biodegradable and recyclable. Hence, said granule according to the first aspect thus provides a sustainable and recyclable packaging material that may assist the society further in the direction of creating a circular bio-economy. Also said granule enables the usage of EPS-forming equipment for making packages whereby said granule is used instead of PS that is expanded into molded EPS. Thus, there is no need for making costly adjustments in the equipment when using said granule instead of PS (such as (expanded) PS spheres). Moreover, the size and the bulk density of the expandable granule can be tailored according to need as well as the density of the molded product obtained therefrom.

The expandable granule according to the first aspect comprises lignocellulosic material. In principle the lignocellulosic material can be any type of lignocellulosic material well-known to the skilled person. The term “lignocellulosic material" refers to plant dry matter and is also called lignocellulosic biomass. Lignocellulosic material is normally composed of two kinds of carbohydrate polymers, cellulose and hemicellulose, and an aromatic-rich polymer called lignin. Preferably, the lignocellulosic material is cellulosic fibers. The lignocellulosic material may be virgin material or already recycled material, such as recycled fibers, or rejected material, such as rejected fibers, (i.e. material which is virgin material, but which has not passed certain quality control steps for other applications), or a combination thereof, it is preferred that the lignocellulosic material comprises at least some recycled or rejected material, and preferably mainly (such as more than 50 wt.%, more than 70 wt.%, more than 80 wt.-% or more than 90 wt.%) comprises recycled or rejected material. Most preferably, the lignocellulosic material essentially consists of recycled or rejected material.

According to a preferred embodiment of the first aspect, said cellulosic fibers may emanate from softwood or hardwood or a combination thereof, preferably hardwood, such as birch or eucalyptus, or a combination thereof, most preferred obtained through a chemical process. Said cellulosic fibers may emanate from ground wood (grinding pulp), chemi-thermo-mechanical pulp (CTMP), such as BCTMP, i.e. bleached CTMP, thermomechanical pulp (TMP), Kraft pulp, sulphate pulp, sulfite pulp, non-wood pulp, recycled pulp material (recycled fibers), pulp for paper and board and/or for carton or combinations thereof. Most preferred said cellulosic fibers are obtained through a chemical process as when manufacturing e.g. CTMP or BCTMP. The cellulosic fibers may emanate from bleached or non-bleached pulp, or a combination thereof. The cellulosic fibers may emanate from hardwood (such as eucalyptus, beech, oak, birch) or softwood (such as pine or spruce), or a combination thereof. Straw, reed, bamboo and bagasse or a combination thereof are also feasible raw material also in said context. Preferred source is as said, hardwood; especially preferred birch or eucalyptus, or a combination thereof.

The expandable granule according to the first aspect further comprises one or more expandable particles, and/or pre-expanded particles.

It is intended throughout the present description that the expressions “expandable particles” and/or “pre-expanded particles” embrace any expandable particle useful in the context of the present invention. Such particles may be any particle which is expandable, i.e. which increases its volume for instance when being heated. Such particles may for instance be expandable microspheres. Examples of such expandable microspheres are microspheres marketed under the tradename Expancel® Microspheres by Nouryon. These particles may also be preexpanded particles, i.e. expandable particles, which have already been partially but not yet fully expanded, and which upon exposure to heat, e.g. by means of hot gases, such as steam, will expand further. Expandable particles and/or pre-expanded particles comprise a polymeric shell and a hollow core containing a blowing agent. Upon heating the blowing agent in the expandable particles and/or pre-expanded particles increases its pressure and hence expands the polymeric shell resulting in an expanded particle. Expandable particles and/or pre-expanded particles are discrete particles, i.e. single particles which are separated from each other, with one single hollow core which is enclosed by the polymeric shell,

All known kinds of expandable microspheres, in particular all known types of expandable thermoplastic microspheres can be used in the granules according to the present invention, such as those marketed under the trademark Expancel® as said above. The expandable thermoplastic microspheres can be of fossil based or bio-based polymer material. Useful expandable microspheres are described in the literature, for example in U.S. Pat. Nos. 3,615,972, 3,945,956, 4,287,308, 5,536,756, 6,235,800, 6,235,394 and 6,509,384, 6,617,363 and 6.984,347, in US Patent Applications Publications US 2004/0176486 and 2005/0079352, in EP 486080, EP 1230975, EP 1288272, EP 1598-405, EP 1811007 and EP 1964903, in WO 2002/096635, WO 2004/072160, WO 2007/091960, WO 2007/091961 and WO 2007/142593, and in JP Laid Open No. 1987-286534 and 2005-272633. Suitable expandable thermoplastic microspheres typically have a thermoplastic shell made from polymers or co-polymers obtainable by polymerizing various ethylenically unsaturated monomers, which can be nitrile containing monomers, such as acrylonitrile, methacrylonitrile, alpha chloroacrylonitrile, alphaethoxyacrylonitrile, fumaronitrile or crotonitrile; acrylic esters such as methylacrylate or ethyl acrylate; methacrylic esters such as methyl methacrylate, isobornyl methacrylate or ethyl methacrylate: vinyl halides such as vinyl chloride; vinylidene halides such as vinylidene chloride; vinyl esters such as vinyl acetate; styrenes such as styrene, halogenated styrenes or alphamethyl styrene; dienes such as butadiene, isoprene and chloroprene; or other kinds of monomers such as vinyl pyridine. Suitable monomers might also be those which have been obtained from renewable sources and, hence, are bio-based, such as for instance lactone- based monomers (e.g. in WO 2019/043235 A1), itaconate dialkylester monomers (e.g. in WO 2019/101749 A1), or tetrahydrofurfuryl (meth)acrylate monomers (e.g. in WO 2021/198487 A1 and WO2021/198492 A1). Any mixtures of the abovementioned monomers may also be used. In some embodiments, it is preferable that the expandable particles and/or pre-expanded particles comprise monomers from renewable sources. It may sometimes be desirable that the monomers for the polymer shell also comprise crosslinking multifunctional monomers, such as one or more of divinylbenzene, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, 1 ,4- butanediol di(meth)acrylate, 1 ,6-hexanediol di(meth)acrylate, glycerol di(meth)acrylate, 1 ,3- butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1 ,10-decanediol di(meth)acrylate, 15 pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol hexa(meth)acrylate, dimethylol tricyclodecane di(meth)acrylate, triallylformal tri(meth)acrylate, allyl methacrylate, trimethylol propane tri(meth)acrylate, trimethylol propane triacrylate, tributanediol di(meth)acrylate, PEG #200 di(meth)acrylate, PEG #400 di(meth)acrylate, PEG #600 di(meth)acrylate, 3-acryloyloxyglycol monoacrylate, triacryl formal or triallyl isocyanate, triallyl isocyanurate etc. If present, such crosslinking monomers preferably constitute from 0.1 to 1 wt.%, most preferably from 0.2 to 0.5 wt.% of the total amounts of monomers for the polymer shell. Preferably, the polymer shell constitutes from 60 to 95 wt.%, most preferably from 70 to 85 wt.%, of the total microsphere. The softening temperature of the polymer shell, normally corresponding to its glass transition temperature (T_g), is preferably within the range of from 50 to 250° C., or from 70 to 230° C. The foaming agent encapsulated by the polymer shell in a microsphere is normally a liquid having a boiling temperature not higher than the softening temperature of the thermoplastic polymer shell. The foaming agent, also referred to as blowing agent or propellant, may be at least one hydrocarbon, such as n- pentane, isopentane, neopentane, n-butane, isobutane, n-hexane, isohexane, neohexane, n- heptane, isoheptane, n-octane and isooctane, or any mixture thereof. Also, other hydrocarbon types may be used, such as petroleum ether, and chlorinated or fluorinated hydrocarbons, such as methyl chloride, methylene chloride, dichloro ethane, dichloroethylene, trichloroethane, trichloroethylene, trichlorofluoromethane, etc. Particularly preferred foaming agents comprise at least one of isobutane, isopentane, isohexane, cyclohexane, isooctane, isododecane, and mixtures thereof. The foaming agent suitably makes up from 5 to 40 wt.% of the total weight of the microsphere. The boiling point of the foaming agent at atmospheric pressure may be within a wide range, preferably from -20 to 200° C., most preferably from -20 to 150° C., and most preferably -20 to 100° C. The thermally expandable thermoplastic microspheres are heated to effect expansion thereof. The temperature at which the expansion of the microspheres starts is called Tstart while the temperature at which maximum expansion is reached is called T_max , both determined at a temperature increase rate of 20° C. per minute. The thermally expandable microspheres used in the present invention suitably have a Tstart of from 50 to 200° C., preferably from 70 to 180° C., most preferably from 70 to 150° C. The thermally expandable microspheres used in the present invention suitably have a T_max of from 70 to 300° C., preferably from 80 to 250° C., most preferred from 100 to 200° C. The expandable microspheres preferably have a volume median diameter of from 1 to 500 pm, more preferably from 5 to 100 pm, most preferably from 10 to 70 pm, as determined by laser light scattering on a Malvern Master sizer Hydro 2000 SM apparatus on wet samples. By heating to a temperature above T_max, it is normally possible to expand the microspheres from 2 to 5 times their original diameter or more, preferably from 3 to 5 times their original diameter. Pre-expanded particles can be prepared from any of the above-described expandable particles.

The presence of expandable particles and/or the pre-expanded particles ensures that the expandable granule of the first aspect of the present invention is expandable. According to a preferred embodiment the expandable particles are thermally expandable thermoplastic microspheres or pre-expanded thermally expandable thermoplastic microspheres, or a combination thereof.

The granule as such can in principle have any granular form. However, it is preferred that the granule is essentially spherical. Also the size of the expandable granule as such is in principle not limited, However, in view of processability thereof, it is desirable that the expandable granule has an average diameter of less than 10 mm, preferably less than 5 mm, more preferably less than 3 mm, and most preferably less than 2 mm. In some embodiments, the expandable granule has an average diameter of more than 0.01 mm, such as more than 0.05 mm or more than 0.1 mm.

The average diameter of a granule can be determined by the skilled person using commonly known techniques, such as image analysis, such as microscopy. The average diameter of a plurality of granules can also be determined by the skilled person using commonly known techniques, such as image analysis, such as microscopy, or dynamic light scattering methods, for instance using a Malvern Mastersizer 2000.

In some embodiments, the expandable granule comprises less than 12 wt.%, preferably less than 10 wt.%, such as less than 8 wt.% or less than 7 wt.%, and more preferably less than 5 wt.%, such as less than 4 wt.% or less than 3 wt.%, of the one or more expandable particles and/or pre-expanded particles, the wt.% being based on the total weight of the expandable granule. In some embodiments, the expandable granule comprises more than 0.01 wt.%, preferably more than 0.1 wt.%, such as more than 0.2 wt.% or more than 0.5 wt.%, and more preferably more than 1 wt.%, such as more than 1 .5 wt.%, of the one or more expandable particles and/or pre-expanded particles, the wt.% being based on the total weight of the expandable granule. Hence, in some embodiments, the amount of the one or more expandable particles and/or pre-expanded particles in the expandable granule is from 0.01 to 12 wt.%, such as from 0.1 to 10 wt.%, preferably from 0.5 to 7 wt.%, and more preferably from 1 to 5 wt.%, such as from 1 .5 to 4 wt.%, the wt.% being based on the total weight of the expandable granule.

In some embodiments, the expandable granule comprises 50 wt.% or more, preferably 70 wt.% or more, more preferably 80 wt.% or more, such as 85 wt.% or more, and most preferably 90 wt.% or more, such as 92 wt.% or more or even 95 wt.% or more, of the lignocellulosic material, the wt.% being based on the total weight of the expandable granule. In some embodiments, the expandable granule comprises 99.99 wt.% or less, preferably 99.9 wt.% or less, more preferably 99.5 wt.% or less, such as 99 wt.% or less or 98 wt.% or less, and most preferably 97 wt.% or less, such as 95 wt.% or less, 92 wt.% or less, or 90 wt.% or less, of the lignocellulosic material, the wt.% being based on the total weight of the expandable granule. Hence, in some embodiments, the amount of the lignocellulosic material in the expandable granule is from 50 to 99.99 wt.%, such as from 70 to 99.9 wt.% or from 80 to 99 wt.%; preferably from 85 to 98 wt.%, and more preferably from 90 to 97 wt.%, the wt.% being based on the total weight of the expandable granule. In some embodiments, the weight ratio of the lignocellulosic material and the one or more expandable particles and/or pre-expanded particles in the expandable granule of the first aspect is from 99.99/0.01 to 88/12, such as from 99.9/0.1 to 90/10, or from 99/1 to 90/10, or from 98/2 to 90/10 or from 95/5 to 90/10. In some embodiments, it is preferred that the relative amount on a weight basis of lignocellulosic material to the one or more expandable particles and/or preexpanded particles in the expandable granule is 5/1 (wt./wt.) or more, preferably 7/1 (wt./wt.) or more, more preferably 8/1 or more, and even more preferably 10/1 (wt./wt.) or more. In some embodiments, the relative amount on a weight basis of lignocellulosic material to the one or more expandable particles and/or pre-expanded particles in the expandable granule is 100/1 (wt./wt.) or less, preferably 90/1 (wt./wt.) or less, more preferably 80/1 or less, and even more preferably 70/1 (wt./wt.) or less.

The expandable granule may further comprise a binding agent (also referred to a “binder” herein). Binding agents are usually polymers and may improve the stability of the expandable granules, usually by providing additional adhesion between the lignocellulosic material and the one or more expandable particles and/or pre-expanded particles. In principle any known binding agent can be used. Preferred are binding agents which are one or more polymer(s) with the ability to form hydrogen bonding with the lignocellulosic material, such as cellulose fibers.

In some embodiments, the binding agent is a polymer of natural origin and is preferably selected from the group consisting of starch, such as cold swelling starch, chitosan, lignin, and cellulose, such as carboxy methyl cellulose (CMC), and any combination thereof, more preferably is starch, and particularly preferably is cationic starch, such as cold swelling cationic starch. The CMC-based binding agent, may have a mass of from 1 to 1000 kDa, such as from 5 to 500 kDa or from 10 to 200 kDa.

The amount of the binder as such in the expandable granule is not limited. However, in some preferred embodiments, the amount of the binder in the expandable granule is up to 5 wt.%, such as up to 4 wt.%, or up to 3 wt.%, and preferably up to 2 wt.%, the wt.% being based on the total weight of the expandable granule. In some preferred embodiments, the amount of the binder in the expandable granule is 0.1 wt.% or more, such as 0.2 wt.% or more, or 0.5 wt.% or more, and preferably 1 wt.% or more, the wt.% being based on the total weight of the expandable granule. Hence, in some embodiments, the amount of the binder in the expandable granule is from, 0.1 to 5 wt.%, such as from 0.2 to 4 wt.%, preferably from 0.5 to 3 wt.%, and most preferably from 1 to 2 wt.%, the wt.% being based on the total weight of the expandable granule. The presence of at the least some binding agent in expandable granule of the present invention has the advantage that potential formation of dust during production, handling and storing of a quantity of expandable granules can be reduced. Moreover, the binding agent may reduce a tendency of a quantity of expandable granules to stick together, for instance when being stored over a certain time period. Hence, a binding agent may improve flowability and handling of a quantity of expandable granules, for instance when being filled into a mold. Also, the binding agent may improve fusing properties of a quantity of expandable granules when being molded.

The expandable granule may further comprise light weight particles. The light weight particles are not limited and in principle any light weight particles commonly known by the skilled person can be comprised in the expandable granule of the present invention. In some embodiment, the light weight particles are lightweight fillers, such as fumed silica, aerogels, fly ash and other porous ceramics, porous aluminium hydroxides or aluminium silicates, porous polymer beads, already fully expanded microspheres, such as fully expanded thermoplastic microspheres, or a combination thereof. A light weight particle has for instance a density of below 0.5 g/cm³, preferably below 0.3 g/cm³, and more preferably below 0.15 g/cm³. A light weight particle may have a minimum density of 0.001 g/cm³, such as a minimum density of 0.005 g/cm³ or a minimum density of 0.01 g/cm³.

The amount of the light weight particles as such in the expandable granule is not limited. However, in some preferred embodiments, the amount of the light weight particles in the expandable granule is up to 10 wt.%, such as up to 8 wt.%, or up to 7 wt.%, and preferably up to 5 wt.%, such as up to 3 wt.%, the wt.% being based on the total weight of the expandable granule. In some preferred embodiments, the amount of the light weight particles in the expandable granule is 0.1 wt.% or more, such as 0.2 wt.% or more, or 0.5 wt.% or more, and preferably 1 wt.% or more, the wt.% being based on the total weight of the expandable granule. Hence, in some embodiments, the amount of the light weight particles in the expandable granule is from, 0.1 to 10 wt.%, such as from 0.2 to 8 wt.%, preferably from 0.5 to 5 wt.%, and most preferably from 1 to 3 wt.%, the wt.% being based on the total weight of the expandable granule.

The light weight particles may help to reduce the average bulk density of the expandable granule and can be used to adjust the average bulk density of the expandable granule to a certain desired average bulk density.

The expandable granule may further comprise gas entrapments, such as air entrapments, which are different from the gas (i.e. the blowing agent) contained in the expandable or pre-expanded microspheres. These entrapments may further reduce the density of the expandable granule. Such additional gas entrapments, such as air entrapments, may be present up to 50 vol.%, such as up to 30 vol.%, or up to 20 vol.%, or up to 10 vol.%, based on the total volume of the expandable granule. In some embodiments, such additional gas entrapments, such as air entrapments, may be present in an amount of from 0.01 to 50 vol%, such as 0.1 to 50 vol%, or 0.5 to 50 vol.%, preferably from 0.1 to 30, from 1 to 30 vol.%, or from 2 to 20 vol.%, based on the total volume of the expandable granule. The gas entrapments, such as air entrapments, may be the result of the presence of pre-expanded particles or light-weight particles as well as a result from the manufacturing process of the expandable particle.

For instance, the expandable granule may comprise:

(i) lignocellulosic material in an amount of from 50 wt.% or more, preferably 70 wt.% or more;

(ii) one or more expandable particles and/or pre-expanded particles in an amount of 0.01 - 12 wt.%, preferably 0.1 - 10 wt.%;

(iii) optional binding agents in an amount of 5 wt.% or less, preferably 4 wt.% or less;

(iv) optional light weight particles in an amount of 10 wt.% or less, preferably 8 wt.% or less, the total weight of the expandable granule, preferably of the components (i)-(iv), summing up to 100 wt.%.

In a preferred embodiment, the expandable granule may comprise:

(i) lignocellulosic material in an amount of from 70 - 98 wt.%, preferably 80 - 95 wt.%;

(ii) one or more expandable particles and/or pre-expanded particles in an amount of 1 - 7 wt.%, preferably 0.1 - 5 wt.%;

(iii) binding agents in an amount of 0.1 - 5 wt.%, preferably 0.2 - 4 wt.% or less;

In a more preferred embodiment, the expandable granule may comprise:

(i) lignocellulosic material in an amount of from 85-98 wt.%, preferably 90-95 wt.%;

(ii) one or more expandable particles and/or pre-expanded particles in an amount 1 -7 wt.%, preferably 1 -5 wt.%;

(iii) optional binding agents in an amount of 4 wt.% or less, preferably 3 wt.% or less;

(iv) optional light weight particles in an amount of 5 wt.% or less, preferably 3 wt.% or less, the total weight of the expandable granule, preferably of the components (i)-(iv), summing up to 100 wt.%. In a particularly preferred embodiment, the expandable granule may comprise:

(iii) binding agents, preferably starch, in an amount of 0.01 to 4 wt.%, preferably 0.01 to 3 wt.%;

(iv) optional light weight particles in an amount of 5 wt.% or less, preferably 3 wt.% or less, the total weight of the expandable granule, preferably of the components (i)-(iv), summing up to 100 wt.%.

The expandable granule may further comprise at least one coating on at least a part of the surface thereof. Preferably, the expandable granule is completely coated with at least one coating. In some embodiments, the expandable granule may further comprise at least two coatings, such as at least three coatings on at least a part of the surface thereof. In some embodiments, expandable granule is completely coated with at least two coatings, such as at least three coatings. Preferably the expandable granule comprises two coatings on its surface and more preferably the expandable granule comprises three coatings on its surface.

The type of coating as such is not limited and in principle any suitable coating(s) known by the skilled person can be used. In some embodiments, the coating(s) is/are selected from any of the binding agents as already defined above, and/or expandable microspheres or pre-expanded microspheres as already defined above. Any of the at least one coating can be independently applied in an average thickness of from 1 pm to 3 mm, such as from 2 pm to 2 mm, or from 2 pm to 1 mm.

The expandable granules of the present invention have a bulk density of from about 0.05 to about 0.8 g/cm³, preferably from about 0.1 to about 0.8 g/cm³, and more preferably from 0.1 to 0.7 g/cm³, such as from 0.1 to 0.6 g/cm³ or from 0.1 to 0.5 g/cm³.

In some embodiments, the expandable granule comprises less than 10 wt %, preferably less than 5 wt.%, even more preferably less than 3 wt.%, and most preferably less than 2 wt.% of one or more fossil based polymers. In some embodiments, the expandable granule is completely free of fossil based polymers.

The present invention provides according to a second aspect a process for manufacturing an expandable granule comprising the following steps: a) providing lignocellulosic material, preferably cellulosic fibers, and b) providing one or more expandable particles and/or pre- expanded particles, and optionally light weight particles, and mixing said lignocellulosic material with said particles, preferably involving an additional step of adding a binding agent.

The process according to the second aspect may produce the expandable granule according to the first aspect. Hence, the expandable granule and its physical properties, such as bulk density and average size, and its components, such as the lignocellulosic material, the one or more expandable particles and/or pre-expanded particles, the optional binding agent, the optional light weight filler, and the optional coating may be the same as described above in the context of the first aspect of the present invention to which it is referred here.

The method according to the second aspect comprises providing lignocellulosic material and further providing the one or more expandable particles and/or pre-expanded particles. The lignocellulosic material, preferably lignocellulosic material as already described above in the context of the first aspect, may be provided in any form, such as in dry or wet form. According to a further preferred embodiment of the second aspect said expandable particles and/or preexpanded particles, which may be the expandable particles and/or pre-expanded particles as already described above in the context of the first aspect, are provided as a dry or wet powder, or as particles in slurry form, or as a stable paint-like formulation or in gel form.

After providing the components lignocellulosic material and the one or more expandable particles and/or pre-expanded particles, the components are mixed. Mixing can be performed in any suitable mixing device as long as the mixing devices ensures homogenous mixing of the components. In a further step, the mixed components may be granulized in a step of forming the granules, for instance using any suitable granulator. Usually, a granulator uses a certain pressure, optionally at elevated temperatures (compared to room temperature), to so form granules. However, care has to be taken that the pressure used in the granulator is not too high so that the bulk density of the obtained expandable granules does not exceed a potentially desired maximum, such as 0.8 g/cm³. Moreover, if using elevated temperatures for the granulating, care has also to be taken that the temperatures are not too high so that the one or more expandable particles and/or pre-expanded particles start to expand or even fully expand during the step of forming the granules. Hence, any potentially used elevated temperature needs be adjusted to the expansion characteristics (in particular Tstart) of the particular one or more expandable particles and/or pre-expanded particles used. In some embodiments, granulation is performed using a high shear mixer. In some embodiments, the obtained granules after granulation are dried, for instance in a fluid bed dryer. The process according to the second aspect may comprise an additional step of adding a binding agent, such as a binding agent as described above in the context of the first aspect. The binding agent may be added to an already mixed mixture of the components lignocellulosic material and the one or more expandable particles and/or pre-expanded particles. However, all three components (including the binding agent) can also be separately provided and then mixed together.

The process according to the second aspect may comprise an additional step of adding a lightweight particle, such as a lightweight particle as described above in the context of the first aspect. The lightweight particle may be added to an already mixed mixture of the components lignocellulosic material and the one or more expandable particles and/or pre-expanded particles, optionally also already comprising a binding agent. However, all three components (including the lightweight particle), or all four components (including the binding agent and the lightweight particle) can also be separately provided and then mixed together.

The weight ratio in which the lignocellulosic material and the one or more expandable particles and/or pre-expanded particles, and the optional binding agent, and/or the optional lightweight particle are provided and mixed is not limited as such. In some embodiments the weight ratio of the lignocellulosic material to the one or more expandable particles and/or pre-expanded particles is as defined above in the context of the first aspect of the present invention.

In some embodiments, the lignocellulosic material and the one or more expandable particles and/or pre-expanded particles, and the optional binding agent, and/or the optional lightweight particle are provided and mixed in the absolute weight amount ranges, based on the total weight of the expandable granule, are as described above in the context of the first aspect.

According to a preferred embodiment of the second aspect said process for manufacturing a granule also comprises an additional step of d) adding a coating agent. The coating agent may be any coating agent and used in any amount as already described above in the context of the first aspect of the present invention.

According to a further preferred embodiment of the second aspect, the step of d) adding a coating agent is sub-divided into at least two separate and subsequent steps of d1 ) adding a first coating agent and d2) adding a second coating agent. Of course, also further steps, such as d3) adding of a third coating agent and, optionally, d4) adding of a fourth coating agent may be performed. In each of the at least two steps of adding a coating agent, the added coating agent may be the same or different. Each step of adding a coating agent may form a different layer which may be cured separately or together. A first step of d1 ) adding a first coating agent forms a first layer directly on the surface of the granule. A second step of d2) adding a second coating agent then forms a second layer on the first layer. A third step of d3) adding a third coating agent then forms a third layer on the second layer, and so on. Preferably at least three layers are formed on the granule.

According to a further preferred embodiment of the second aspect, said process for manufacturing a granule also comprises an additional step of e) drying of the granule obtained using the previous steps. Any suitable drying equipment can be used for this step, such as a fluid bed dryer.

The present invention also provides according to a fifth aspect a method for manufacturing of a foamed product, preferably comprising less than about 5 wt.% of a fossil-based polymer, comprising the following steps: i) providing one or more granules according to the first aspect, or obtained by a process according to the second aspect, or one or more granules according to the third aspect, ii) filling said granules into a mold assembly and heating said material, preferably to from about 50 to about 150 °C, more preferably to from about 50 to about 130 °C, most preferred to from about 60 to about 120 °C, thus providing an expanded foamed product.

The heating may further e.g. be done in in an oven or in an autoclave, or a combination thereof.

According to a preferred embodiment of the fifth aspect hot steam is applied during step ii) for expanding said granules. According to a preferred embodiment of the fifth aspect the density of said finalized foamed product is from about 0.01 to about 0.5 g/cm³, preferably from about 0.025 to about 0.5 g/cm³, such as from about 0.05 to about 0.5 g/cm³, or from about 0,05 to about 0,3 g/cm³.

According to a preferred embodiment, the product obtained in step (ii) can be subjected to a sintering treatment (iii). During such sintering step, the product obtained in step (ii) is kept at a temperature between 50-150°C for a certain time span, such as for at least 1 minute, or at least 5 minutes, or at least 10 minutes, and for instance up to 2 hours or up to 1 hour. The sintering step may improve the stability and/or uniformity of the product.

When it comes to said fourth aspect viz. use of a granule according to the first or third aspect in the manufacturing of a foamed material, such as a chock absorbing material, or in an insulation material for building constructions or in an isolation material for keeping warm or cold food or food ingredients, the chock absorbing material may be a part of a helmet or other safety equipment. When it comes the usage in the manufacture of an isolation material for keeping warm or cold food or food ingredients, it may be part of a cooling box for keeping fish and/or other see food (lobsters, cray fish, shrimps and similar) fresh. It may also be used in trays for keeping fresh vegetables or fruit. When used as a material for building constructions this may be part of a building (house and such) or a furniture.

Preferred features of each aspect of the invention are as for each of the other aspects mutatis mutandis. The prior art document (s) mentioned herein are incorporated to the fullest extent permitted by law. The invention is further described in the following examples, together with the appended figures, which do not limit the scope of the invention in any way.

Embodiments of the present invention are described as mentioned in more detail with the aid of examples of embodiments, together with the appended figures, the only purpose of which is to illustrate the invention and are in no way intended to limit its extent.

Figures

Figure 1 shows in Fig. 1a) and Fig. 1 b) tests regarding short and long fibers for preparing the expandable granule of the present invention. In Fig.1 b) it is shown that wet fibers from pine needles have a tendency to clump together as these fibers are longer fibers that cause lumping. The length of said fibers have double the length to that of birch which do not have such tendency to clump (see Fig 1 a). Nonetheless, the clumping is not per se detrimental for the expandable granule of the present invention.

Fig. 1c) shows expandable granules of the present invention prepared by using different fiber types in a fill test (the funnel represents a potential form of a quite specific mold). The granules comprise 93 wt.% of the respective fibers (birch (Fig. 1 c1 )), eucalyptus (Fig. 1c2)), or pine (Fig. 1c3))), 5 wt.% of expandable microspheres (available under the tradename Expancel

(031 DU40)), and 2 wt.% starch as a binding agent. It can be seen that the birch and eucalyptusbased expandable granules have better filling properties than the pine-derived expandable granules.

Fig. 1d) shows expandable granules comprising different types of binding agents, i.e. starch and different types of carboxy methyl cellulose (CMC), namely cold-water soluble starch, CMC 40 kDa, CMC 100 kDa, and CMC 250 kDa.

Fig. 1 e) shows pictures of the expandable granules of the present invention before and after different Laboratory pulp refiner (PFI)-m illing treatments, namely a reference (before treatment), after PFI 500 RPM (revolution per minute) (ca. 40 kWh/ton) treatment, after PFI 5000 RPM (ca. 400 kWh/ton) treatment, and after PFI 10000 RPM (ca. 800 kWh/ton) treatment, respectively.

Fig 1f) shows how wet wood fiber flakes (size 2-5 mm, 20-30 wt.% solid content based on the total weight of the wet wood fiber flakes) are combined with expandable microspheres (available under the tradename Expancel 031 WUF40) (in the form of a wet paste), by optionally adding a binding agent (“binder”), giving granules.

Figure 2 shows a schematic picture (Fig. 2a) and a microscopy picture (Fig. 2b) of a preferred embodiment of the expandable granule of the present invention (also referred to herein as “Granuler+”). In Fig. 2a) there is depicted a core (1 ) which comprises lignocellulosic fibers (10), expandable microspheres (11 ) and/or pre-expanded microspheres (12), light weight filler (13) and optionally binder, and a coating layer (2) comprising expandable microspheres (21 ) and/or pre-expanded microspheres (22), and a coating (23). The coating may for instance be a binder, such as described above. Fig. 2b) shows a microscopy picture of such Granuler+.

Figure 3 shows how the expandable granule of the present invention may be applied when manufacturing a molded article, such as a package. This is further highlighted in Fig. 3a), i.e. a step of granulation of the expandable granule in a high-shear mixer, in Fig. 3b). i.e. drying the expandable granules after granulation in a fluid bed dryer, Fig. 3c), i.e. filling the expandable granules in a mold before putting the filled mold into an oven at 150 °C, and Fig. 3d), i.e. the molded material after treatment in an oven for 15 min, respectively. Fig. 3e) shows the product obtained when casting the material (i.e. the expandable granules) in a different mold, i.e. a cylindrical mold, after molding and sintering.

Figure 4 shows in Fig. 4a) the application of the expandable granule of the present application in full scale application. Fig. 4b) shows the release of the molded (and expanded) product in full scale test from mold.

Figure 5 shows molded products made from expandable granules of the present invention, wherein the expandable granules comprise recycled fibers (Fig. 5a) and rejected fibers (Fig. 5b and Fig. 5c)), respectively.

Examples

Example 1

Example 1 a

92.5 wt.% pine fiber (bleached kraft pulp), 5 wt.% expandable microspheres (available as 031 WUF40 from Nouryon) and 2.5 wt.% CMC (available as Finnfix 30F from Nouryon, added as a solution in water) was mixed in a kitchen mixer with extra water to a total solid content of 25 wt.%.

The mix was formed into granules as described schematically in Figure 1 f) with the use of a high shear granulator (Diosna P1 -6 Laboratory Mixer Figure 3a)). The granules were dried to 45% (solid content) in a fluidized bed (module MINILAB RC, Diosna, Figure 3b)) and the granules were analysed by visual inspection, microscopy, and filling test for flowability.

It is concluded that long fibers from pine make “hairy”, non-spherical granules. Such non- spherical granules might be less suitable for specific complex mold shapes as shown in Figure 3c). However, such non-spherical granules are of course still suitable for use in less complex mold shapes like bricks or cylinders. Figures 1 b) and 1 c3) show the granules made in this example.

Example 1 b

92.5 wt.% birch fiber (bleached kraft pulp), 5 wt.% expandable microspheres (available as 031 WUF40 from Nouryon) and 2.5 wt.% CMC (available as Finnfix 30F from Nouryon, added as a solution in water) was mixed in a kitchen mixer with extra water to a total solid content of 25 wt.%. The mix was formed into granules as described schematically in Figure 1f) with the use of a high shear granulator (Diosna, P1-6 Laboratory Mixer Figure 3a)). The granules were dried to 45% (solid content) in a fluidized bed (module MINILAB RC, Diosna, Figure 3b)) and analysed by visual inspection, microscopy, and filling test for flowability.

It is concluded that short fibers from birch make spherical granules with a fairly smooth surface that can be filled also in specific complex mold shapes for production of molded EPS articles. Figures 1 a and 1c3) show the granules made in this example.

The granules filled a mold (Figure 3c)) which was subsequently heated to —150 °C for 15 minutes. Figure 3d) also shows the resulting fused (or molded) material.

Example 1c

92.5 wt.% eucalyptus fiber (bleached kraft pulp), 5 wt.% expandable microspheres (available as 031 WUF40 from Nouryon) and 2.5 wt.% CMC (available as Finnfix 30F from Nouryon, added as a solution in water) was mixed in a kitchen mixer with extra water to a total solid content of 25 wt.%.

The mix was formed into granules as described schematically in Figure 1f) with the use of a high shear granulator (Diosna P1 -6 Laboratory Mixer , Figure 3a)). The granules were dried to 45% (solid content) in a fluidized bed (module MINILAB RC, Diosna, Figure 3b)) and analysed by visual inspection, microscopy, and filling test for flowability.

It is concluded that short fibers from eucalyptus make, spherical granules with a fairly smooth surface that can be filled also in specific complex mold shapes for production of molded EPS articles. Figure 1c2) shows the granules made in this example.

Example 1d

94 wt.% birch fiber (bleached kraft pulp), 5 wt.% expandable microspheres (available as

031 WUF40 from Nouryon) and 1 wt.% cold-water-soluble starch (available as Solbond PC 65L from SOLAM; added as a solution in water) was mixed in a kitchen mixer with extra water to a total solid content of 25 wt.%.

The mix was formed into granules as described schematically in Figure 1f) with the use of a high shear granulator (Diosna, Figure 3a)). The granules were dried to 45% (solid content) in a fluidized bed (Diosna, Figure 3b)) and analysed by visual inspection, microscopy, and filling test for flowability.

It is concluded that also starch works as a binder in this system, to make spherical granules from birch fiber (bleached kraft pulp) with a fairly smooth surface that can be filled also in specific complex mold shapes for production of molded EPS articles.

Example 1 e

94 wt.% recycled pulp (i.e. recycled fibers), 5 wt.% expandable microspheres (available as 031 WUF40 from Nouryon) and 1 wt.% cold-water-soluble starch (available as Solbond PC 65L from SOLAM; added as a solution of water) was mixed in a kitchen mixer with extra water to a total solid content of 25 wt.%.

It is concluded that the recycled pulp makes spherical granules with a fairly smooth surface that can be filled also in specific complex mold shapes for production of molded EPS articles. Figure 5a) shows a molded article made from granules of recycled pulp.

Example 1f

94 wt.% rejected pulp (i.e. rejected fibers), 5 wt.% expandable microspheres (available as 031 WUF40 from Nouryon) and 1 wt.% cold-water-soluble starch (available as Solbond PC 65L from SOLAM; added as a solution of water) was mixed in a kitchen mixer with extra water to a total solid content of 25 wt.%.

The mix was formed into granules as described schematically in Figure 1 f) with the use of a high shear granulator (Diosna, Figure 3a)). The granules were dried to 45% in a fluidized bed (Diosna, Figure 3b)) and analysed by visual inspection, microscopy, and filling test for flowability.

It is concluded that the reject pulp makes spherical granules with a smooth surface that can be filled also in specific complex mold shapes for production of molded EPS articles. Figures 5b) and 5c) show molded articles made from granules of reject pulp. Example 2

Various CMCs (available as a Finnfix product from Nouryon) were studied in different forms and with different molecular weights (40 kDa, 100 kDa, and 250 kDa) as potential binding agents and were compared with cold-water-soluble starch as binding agent. The resulting granules, produced as described in Examples 1 b and 1d above, take different shapes as can be seen in Figure 1d). The results show that type of binder and its molecular weight influences the final morphology of the granules. CMC of 100 kDa (Finnfix 30F) has the best binding performance.

Example 3

Trials were carried out where milling of birch fiber to different grades were performed. The granules produced from birch fibers with different degree of milling is depicted in Figure 1 e. Even short birch fibers show some tendencies to make “hairy” granules. By grinding the fibers in wet form (Escher Wyss lab grinder), it is possible to modify length and surface of the fibers, which in turn affect the morphology of the granules. Milling the birch fibers at 5000 rpm seem to have the best effect for making granules with spherical form and with a smooth surface that perform well in the filling tests.

Example 4

Granules from Example 1c were spray coated with a 2.5 wt.% CMC solution in water to a thin layer in the granulator tool without the use of high-speed shopper. Expandable microspheres (available as Expancel 031 WUF40 from Nouryon) were subsequently added while the granules were in motion. An excess of microspheres was added for visible effects. The expandable microspheres were adsorbed at the granules’ surfaces by the wet, sticky CMC to make a coreshell granulated product with a surface coating of expandable microspheres. Figure 2a) schematically illustrates the core-shell principle and Figure 2b) shows a SEM image of a crosssection of such a core-shell granule.

Example 5

The recipe from a combination of Examples 1 b, 2 and 3 was used to test molding in larger scale using equipment normally used for making molded EPS. A full-scale trial on an EPS moulding machine showed that the granules fill the mold and fuses nicely by the steam used to heat the material in the mold (Figures 4a) and 4b)).

It could be confirmed that:

• The material, i.e. the expandable granules of the present invention, behave in a similar way as when EPS is manufactured.

• The material can be filled into molds of different shapes. The granules expand and fuse into one molded article.

The molded article can be released from the mold.

Potentially also one or more releasing agents may be involved for enabling relatively easy release of the fused material from the tool (which may stick to the tool, i.e. the mold). The tool was filled with the expandable granules of the present invention (approx. 30-35 litres) and was subsequently heated with hot steam in making the granules expand in the mold and fuse together into a shaped article. Thus, a foamed product was manufactured from expandable granules in a mold for production of molded EPS, in line with the previously mentioned steps in accordance with the fourth aspect of the present invention.

Various embodiments of the present invention have been described above but a person skilled in the art realizes further minor alterations that would fall into the scope of the present invention. The breadth and scope of the present invention should not be limited by any of the abovedescribed exemplary embodiments but should be defined only in accordance with the following claims and their equivalents. For example, any of the above-noted granules/compositions or methods may be combined with other known methods. Other aspects, advantages- and modifications within the scope of the invention will be apparent to those skilled in the art to which the invention pertains.

Claims

1 . An expandable granule comprising lignocellulosic material and one or more expandable particles and/or pre-expanded particles, and optionally light weight particles, optionally also containing one or more binding agents, wherein the expandable granule has a bulk density from about 0.05 to about 0.8 g/cm³, preferably from about 0.1 to about 0.8 g/cm³.

2. The expandable granule according to claim 1 , wherein the expandable granule comprises less than 12 wt.%, preferably less than 10 wt.%, and more preferably less than 5 wt.% of the one or more expandable particles and/or pre-expanded particles.

3. The expandable granule according to claim 1 or 2, wherein the expandable granule comprises 50 wt.% or more, preferably 70 wt.% or more, more preferably 80 wt.% or more, and most preferably 90 wt.% or more of the lignocellulosic material.

4. The expandable granule according to any one of claims 1 to 3, wherein the weight ratio of the lignocellulosic material and the one or more expandable particles and/or preexpanded particles is from 99.99/0.01 to 88/12.

5. A process for manufacturing an expandable granule comprising the following steps: a) providing lignocellulosic material, preferably cellulosic fibers, and b) providing one or more expandable particles and/or pre-expanded particles, and optionally light weight particles, and mixing said lignocellulosic material with said particles, preferably involving an additional step of adding a binding agent.

6. The process for manufacturing an expandable granule according to claim 5, wherein the weight ratio of the lignocellulosic material to the one or more expandable particles and/or pre-expanded particles is from 99.99/0.01 to 88/12.

7. The process for manufacturing an expandable granule according to claim 5 or 6, wherein said expandable particles are provided as a dry or wet powder, or as particles in slurry form or in gel form.

8. The process for manufacturing an expandable granule according to any one of claims 5 to 7, wherein said expandable particles are thermally expandable thermoplastic microspheres or thermally pre-expanded microspheres, or a combination thereof.

9. The process for manufacturing a granule according to any one of claims 5 to 8, wherein the binding agent of the additional step in b) is one or more polymer(s) with the ability to form hydrogen bonding with cellulose fibers, preferably selected from the group consisting of starch, chitosan, carboxy methyl cellulose, and any combination thereof, most preferred starch, wherein said polymer(s) especially preferred is added so that it is present in an amount up to about 2 wt.%.

10. The process for manufacturing a granule according to any one of claims 5 to 7, also comprising an additional step c) of adding a coating agent; and/or also comprising an additional step d) of drying of the granule obtained using the previous steps.

11 . The process for manufacturing a granule according any one of claims 5 to 10, further comprising a step of forming at least two layers on said granule, preferably at least three layers.

12. The process for manufacturing a granule according to any one of the preceding claims 5 to 11 , wherein the bulk density of the expandable granule is from about 0.05 to about 0.8 g/cm³, preferably from about 0.1 to about 0.8 g/cm³.

13. The process for manufacturing a granule according to any one of the preceding claims 5 to 12, wherein said granule is made essentially spherical.

14. The process for manufacturing a granule according to any one of claims 5 to 13, wherein said cellulosic fibers emanate from softwood or hardwood or a combination thereof, preferably hardwood, such as birch or eucalyptus, or a combination thereof, most preferred obtained through a chemical process.

15. The process for manufacturing a granule according to any one of claims 5 to 14, wherein said granule comprise less than 5 wt % of one or more fossil based polymers.

16. A granule obtainable by a process according to any one of the preceding claims 5 to 15.

17. Use of a granule according to claim 1 or 16 in the manufacturing of a foamed material, such as a chock absorbing material, or in an insulation material for building constructions or in an isolation material for keeping warm or cold food or food ingredients, such as an environmentally friendly shock absorbing packaging material recyclable with paper board.

18. A method for manufacturing of a foamed product, preferably comprising less than about

5 wt.% of a fossil-based polymer, comprising the following steps: i) providing one or more granules according to any one of claims 1 to 4, or obtained by a process according to any one of claims 5 to 15, or one or more granules according to claim 16, ii) filling said granules into a mold assembly and heating said material, preferably to about 50 - 150 °C, more preferably to about 55 - 130 °C, most preferred to about 60 - 120 °C, thus providing an expanded foamed product.

19. The method according to claim 18, wherein steam is applied during step ii) for expanding said granules.

20. The method according to claim 18 or 19, wherein the density of said finalized foamed product is from about 0.025 to about 0.5 g/cm³, preferably from about 0.025 to about 0.3 g/cm³.

21 . A foamed product obtainable by a method according to any one of claims 18 to 20.