A Filament and a 3D Printed Item

Abstract

A use of a filament in 3D printing is disclosed. The filament includes a thermoplastic polymer and detonation nanodiamonds. The filament exhibits increased tensile strength and thermal conductivity and higher glass transition temperature compared to filaments not including detonation nanodiamonds. 3D items produced with the filament exhibits increased tensile strength and thermal conductivity.

Claims

1. A filament for use in 3D printing comprising a thermoplastic polymer in an amount ranging 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 00105 wt % to 10 wt % in 3D printing, wherein the filament has at least 15% higher tensile strength compared to said filament without detonation nanodiamonds.

2. The filament for use in 3D printing according to claim 1, wherein said thermoplastic polymer comprises Acrylonitrile butadiene styrene, Acrylic, Celluloid, Cellulose acetate, Cyclic Olefin Copolymer, Ethylene-Vinyl Acetate, Ethylene vinyl alcohol, Fluoroplastics such as polytetrafluoro ethylene and perfluoroalkoxy alkanes, Ionomers, Liquid Crystal Polymer, Polyoxymethylene, Polyacrylates, Polyacrylonitrile, Polyamide, Polyamide-imide, Polyimide, Polyaryletherketone, Polybutadiene, Polybutylene, Polybutylene terephthalate, Polycaprolactone, Polychlorotrifluoroethylene, Polyether ether ketone, Polyethylene terephthalate, Polycyclohexylene, dimethylene terephthalate, Polycarbonate, Polyhydroxyalkanoates, Poly-ketone, Polyester, Polyethylene, Polyetherketoneketone, Polyetherimide, Polyethersulfone, Polysulfone, Chlorinated Polyethylene, Polylactic acid, Polymethylmethacrylate, Polymethylpentene, Polyphenylene, Polyphenylene oxide, Polyphenylene sulfide, Polyphthalamide, Polypropylene, Polystyrene, Polysulfone, Polytrimethylene terephthalate, Polyurethane, Polyvinyl acetate, Polyvinyl chloride, Polyvinylidene chloride, and Styrene-acrylonitrile, any Thermoplastic elastomer or the combinations thereof; preferably the thermoplastic polymer is Acrylonitrile butadiene styrene (ABS), Polylactic acid (PLA), Nylon (aliphatic or aromatic polyamide), Polypropylene (PP), Polyethylene (PE), Polyethylene terephthalate (PET) and Polycarbonate (PC), more preferably Polylactic acid.

3. The filament for use in 3D printing according to claim 1, wherein the detonation nanodiamonds exhibit zeta potential higher than +30 mV, preferably higher than +40 mV and more preferably higher than +50 mV.

4. The filament for use in 3D printing according to claim 1, wherein the detonation nanodiamonds exhibit zeta potential value more negative than 30 mV, preferably more negative than −40 mV and more preferably more negative than −50 mV.

5. The filament for use in 3D printing according to claim 1, wherein the detonation nanodiamonds are substantially mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups.

6. The filament for use in 3D printing according to claim 1, wherein the filament has minimum 2° C. higher glass transition temperature (Tg) compared to said filament without detonation nanodiamonds.

7. The filament for use in 3D printing according to claim 1, wherein the filament has at least 2% higher thermal conductivity than said filament without detonation nanodiamonds.

8. (canceled)

9. A 3D printed item comprising a thermoplastic polymer in an amount ranging from 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt %, wherein the item has at least 15% higher tensile strength compared to said item without detonation nanodiamonds.

10. The 3D printed item according to claim 9, wherein said thermoplastic polymer comprises Acrylonitrile butadiene styrene, Acrylic, Celluloid, Cellulose acetate, Cyclic Olefin Copolymer, Ethylene-Vinyl Acetate, Ethylene vinyl alcohol, Fluoroplastics such as polytetrafluoro ethylene and perfluoroalkoxy alkanes, Ionomers, Liquid Crystal Polymer, Polyoxymethylene, Polyacrylates, Polyacrylonitrile, Polyamide, Polyamide-imide, Polyimide, Polyaryletherketone, Polybutadiene, Polybutylene, Polybutylene terephthalate, Polycaprolactone, Polychlorotrifluoroethylene, Polyether ether ketone, Polyethylene terephthalate, Polycyclohexylene, dimethylene terephthalate, Polycarbonate, Polyhydroxyalkanoates, Poly-ketone, Polyester, Polyethylene, Polyetherketoneketone, Polyetherimide, Polyethersulfone, Polysulfone, Chlorinated Polyethylene, Polylactic acid, Polymethylmethacrylate, Polymethylpentene, Polyphenylene, Polyphenylene oxide, Polyphenylene sulfide, Polyphthalamide, Polypropylene, Polystyrene, Polysulfone, Polytrimethylene terephthalate, Polyurethane, Polyvinyl acetate, Polyvinyl chloride, Polyvinylidene chloride, and Styrene-acrylonitrile, any Thermoplastic elastomer or the combinations thereof; preferably the thermoplastic polymer is Acrylonitrile butadiene styrene (ABS), Polylactic acid (PLA), Nylon (aliphatic or aromatic polyamide), Polypropylene (PP), Polyethylene (PE), Polyethylene terephthalate (PET) and Polycarbonate (PC), more preferably Polylactic acid.

11. The 3D printed item according to claim 9, wherein the detonation nanodiamonds exhibit zeta potential higher than +30 mV, preferably higher than +40 mV and more preferably higher than +50 mV; or zeta potential value more negative than −30 mV, preferably more negative than −40 mV and more preferably more negative than −50 mV.

12. The 3D printed item according to claim 9, wherein the detonation nanodiamonds are substantially mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups.

13. The 3D printed item according to claim 9, wherein the item has at least 2° C. higher glass transition temperature (Tg) compared to said item without detonation nanodiamonds.

14. The 3D printed item according to claim 9, wherein the item has at least 2% higher thermal conductivity compared to said item without detonation nanodiamonds.

15. A method for making 3D printed product, the method comprising: melting a filament comprising a thermoplastic material in an amount ranging 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt % in a printing head of a 3D printer; and depositing the molten material in a 3D printer in successive layers to form a 3D printed product.

Description

DETAILED DESCRIPTION

[0051] According to the present invention there is provided a filament for use in 3D printing comprising thermoplastic polymer and detonation nanodiamonds. More particularly there is provided a filament for use in 3D printing, the filament comprising thermoplastic polymer in an amount ranging 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt %, wherein the filament has at least 15% higher tensile strength compared to said filament without detonation nanodiamonds.

[0052] In one embodiment the amount of the thermoplastic polymer is from 80 wt % to 99.995 wt %, preferably from 90 wt % to 99.995 wt %.

[0053] In another embodiment the amount of the thermoplastic polymer is from 80 wt % to 99.5 wt %, preferably from 80 wt % to 99.

[0054] Yet, in another embodiment the amount of the thermoplastic polymer is from 80 wt % to 97 wt %, preferably from 80 wt % to 98.

[0055] The amount of the detonation nanodiamonds is in one embodiment from 0.005 wt % to 0.05 wt %, preferably from 0.005 wt % to 0.04 wt %.

[0056] In other embodiment the amount of the detonation nanodiamonds is from 0.005 wt % to 10 wt %, preferably from 0.01 wt % to 1 wt %, more preferably from 0.01 to 0.5 wt. % and most preferably from 0.01 to 0.2 wt. %.

[0057] Yet, in other embodiment the amount of the detonation nanodiamonds is from 0.005 wt % to 5 wt %, preferably from 0.01 wt % to 5 wt %, more preferably from 0.01 to 3 wt. %.

[0058] In one embodiment the filament has at least 18% higher tensile strength compared to said filament without detonation nanodiamonds, preferably at least 20%, more preferably at least 25%, even more preferably at least 30% and most preferably at least 35% higher tensile strength. Tensile strength measurement can be carried out with a tensile strength testing apparatus, by applying ISO 527 standard. One such apparatus is Zwck Roell 250 KN tensile strength testing apparatus.

[0059] Thermal conductivity of the filament is in one embodiment at least 5% higher, preferably at least 8% higher thermal compared to said filament without detonation nanodiamonds.

[0060] The filament has, in one embodiment, at least 2° C. higher, preferably at least 5° C. higher glass transition temperature (Tg) compared to said filament without detonation nanodiamonds.

[0061] Any suitable thermoplastic polymer can be used. In one embodiment the thermoplastic polymer comprises Acrylonitrile butadiene styrene (ABS), Acrylic, Celluloid, Cellulose acetate, Cyclic Olefin Copolymer, Ethylene-Vinyl Acetate, Ethylene vinyl alcohol, Fluoroplastics such as polytetrafluoro ethylene and perfluoroalkoxy alkanes, Ionomers, Liquid Crystal Polymer, Polyoxymethylene, Polyacrylates, Polyacrylonitrile, Polyamide, Polyamide-imide, Polyimide, Polyaryletherketone, Polybutadiene, Pbutylene, Polybutylene terephthalate, Polycaprolactone, Polychlorotrifluoroethylene, Polyether ether ketone, Polyethylene terephthalate (PET), Polycyclohexylene, dimethylene terephthalate, Polycarbonate (PC), Polyhydroxyalkanoates, Poly-ketone, Polyester, Polyethylene (PE), Polyetherketoneketone, Polyetherimide, Polyethersulfone, Polysulfone, Chlorinated Polyethylene, Polylactic acid (PLA), Polymethylmethacrylate, Polymethylpentene, Polyphenylene, Polyphenylene oxide, Polyphenylene sulfide, Polyphthalamide, Polypropylene (PP), Polystyrene, Polysulfone, Polytrimethylene terephthalate, Polyurethane, Polyvinyl acetate, Polyvinyl chloride (PVC), Polyvinylidene chloride, and Styreneacrylonitrile, Nylon (aliphatic or aromatic polyamide) or the combinations thereof.

[0062] Preferably the thermoplastic polymer is Acrylonitrile butadiene styrene (ABS), Polylactic acid (PLA), Nylon (aliphatic or aromatic polyamide), Polypropylene (PP), Polyethylene (PE), Polyethylene terephthalate (PET) and Polycarbonate (PC), most preferably Polylactic acid.

[0063] The Polylactic acid) PLA occurs as racemates D-racemate (PDLLA) and L-racemate (PLLA).

[0064] In one embodiment the PLA is a mixture of D- and L-racemates. In another embodiment the PLA is D-racemate or L-racemate, preferably L-racemate.

[0065] Also, any suitable thermoplastic elastomers can be used instead or in combination with the thermoplastic polymer. Thermoplastic elastomers (TPE), sometimes referred to as thermoplastic rubbers, are a class of copolymers or a physical mix of polymers (usually a plastic and a rubber), which consist of materials with both thermoplastic and elastomeric properties. In one embodiment is thermoplastic elastomer is a styrenic blockcopolymer (TPS), in another embodiment the thermoplastic elastomer is a thermoplastic polyolefin elastomer (TPO), in yet another embodiment the thermoplastic elastomer is a thermoplastic vulcanizate (TPV), a thermoplastic polyurethane (TPU), a thermoplastic copolyester (TPC), a thermoplastic polyamide (TPA), a non-classified thermoplastic elastomer (TPZ) or a mixture of any known thermoplastic elastomers.

[0066] The detonation nanodiamond can be any suitable nanodiamond known in the art.

[0067] In one embodiment the detonation nanodiamond is mono-functionalized nanodiamond. The detonation nanodiamonds may be mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups.

[0068] Preferably the detonation nanodiamonds are substantially mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups, preferably are mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups.

[0069] In one embodiment the detonation nanodiamonds are substantially amine functionalized. In another embodiment the detonation nanodiamonds are substantially carboxylic acid functionalized. In other embodiment the detonation nanodiamonds are substantially hydrogen functionalized. Yet, in other embodiment the detonation nanodiamonds are substantially hydroxyl functionalized. In another embodiment the detonation nanodiamonds are functionalized substantially with any other anionic, cationic or neutral functional groups.

[0070] The detonation nanodiamonds are commercially available or can be produced with known methods.

[0071] In one embodiment the detonation nanodiamonds exhibit zeta potential higher than +30 mV, preferably higher than +40 mV and more preferably higher than +50 mV. The zeta potential is measured from 0.5 wt % aqueous nanodiamond dispersion at pH 7.

[0072] In another embodiment the detonation nanodiamonds exhibit zeta potential value more negative than −30 mV, preferably more negative than −40 mV and more preferably more negative than −50 mV. The zeta potential is measured from 0.5 wt % aqueous nanodiamond dispersion at pH 7.

[0073] In one embodiment D90 particle size distribution (as measured from 0.5 wt. % nano-diamond dispersion) is less than 15 nm, preferably from 2 nm to 15 nm, more preferably, from 2 nm to 10 nm.

[0074] In a preferred embodiment the filament has diameter of 1.75 mm±0.05 mm or 2.85 mm±0.10 mm.

[0075] The filament may additionally comprise at least one filler other than detonation nanodiamond selected from a group consisting of metal, metal oxide, metal nitride, metal carbide, carbon compound, silicon compound, boron compound such as boron nitride, ceramic materials, natural fibers or the combinations thereof. The carbon compound can be selected from diamond material other than detonation diamond, graphite, carbon black, carbon fiber, graphene, oxidized graphene, carbon soot, carbon nanotube, pyrolytic carbon, silicon carbide, aluminum carbide, carbon nitride, or the combinations thereof.

[0076] The filament can be transparent or substantially transparent. The filament may also comprise a coloring agent, to make the filament available in desired color.

[0077] The filament may be produced by any known suitable method, such as by providing thermoplastic polymer; providing detonation nanodiamonds; compounding the thermoplastic polymer and the detonation nanodiamonds to form a compound; and extruding the compound to form filaments.

[0078] In an exemplary embodiment the filament is produced with a method comprising agitating detonation nanodiamonds and thermoplastic polymer in a liquid medium such as water, to form a solution; removing, the liquid medium from the solution, such as by evaporating and/or drying, to form thermoplastic polymer pellets coated with detonation nanodiamonds; compounding the coated pellets and extruding to form the filament.

[0079] According to the present invention there is also provided use of the filament in 3D printing, the filament comprising the thermoplastic polymer in an amount ranging 80 wt % to 99.99 wt % and the detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt % in 3D, wherein the filament has at least 15% higher tensile strength compared to said filament without the detonation nanodiamonds.

[0080] The thermoplastic polymer and the detonation nanodiamonds have the features defined above. The amounts of the thermoplastic polymer and the detonation nanodiamonds are as defined above. The filament has the same features as defined above.

[0081] According to the present invention there is also provided a 3D printed item comprising thermoplastic polymer in amount ranging from 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt %, wherein the item has at least 15% higher tensile strength compared to said item without detonation nanodiamonds.

[0082] In one embodiment the amount of the thermoplastic polymer is from 80 wt % to 99.995 wt %, preferably from 90 wt % to 99.995 wt %.

[0083] In another embodiment the amount of the thermoplastic polymer is from 80 wt % to 99.5 wt %, preferably from 90 wt % to 99.

[0084] Yet, in another embodiment the amount of the thermoplastic polymer is from 80 wt % to 97 wt %, preferably from 80 wt % to 98.

[0085] The amount of the detonation nanodiamonds is in one embodiment from 0.005 wt % to 0.05 wt %, preferably from 0.005 wt % to 0.04 wt %.

[0086] In other embodiment the amount of the detonation nanodiamonds is from 0.005 wt % to 10 wt %, preferably from 0.01 wt % to 1 wt %, more preferably from 0.01 to 0.5 wt. % and most preferably from 0.01 to 0.2 wt. %.

[0087] Yet, in other embodiment the amount of the detonation nanodiamonds is from 0.005 wt % to 5 wt %, preferably from 0.01 wt % to 5 wt %, more preferably from 0.01 to 3 wt. %.

[0088] In one embodiment the item has at least 18% higher tensile strength compared to said item without detonation nanodiamonds, preferably at least 20%, more preferably at least 25%, even more preferably at least 30% and most preferably at least 35% higher tensile strength. Tensile strength measurement can be carried out with a tensile strength testing apparatus, by applying ISO 527 standard. One such apparatus is Zwck Roell 250 KN tensile strength testing apparatus.

[0089] Thermal conductivity of the item is in one embodiment at least 5% higher, preferably at least 8% higher thermal compared to said item without detonation nanodiamonds.

[0090] The item has, in one embodiment, at least 2° C. higher, preferably at least 5° C. higher glass transition temperature (Tg) compared to said item without detonation nanodiamonds.

[0091] Any suitable thermoplastic polymer can be used. In one embodiment the thermoplastic polymer comprises Acrylonitrile butadiene styrene (ABS), Acrylic, Celluloid, Cellulose acetate, Cyclic Olefin Copolymer, Ethylene-Vinyl Acetate, Ethylene vinyl alcohol, Fluoroplastics such as polytetrafluoro ethylene and perfluoroalkoxy alkanes, Ionomers, Liquid Crystal Polymer, Polyoxymethylene, Polyacrylates, Polyacrylonitrile, Polyamide, Polyamide-imide, Polyimide, Polyaryletherketone, Polybutadiene, Pbutylene, Polybutylene terephthalate, Polycaprolactone, Polychlorotrifluoroethylene, Polyether ether ketone, Polyethylene terephthalate (PET), Polycyclohexylene, dimethylene terephthalate, Polycarbonate (PC), Polyhydroxyalkanoates, Poly-ketone, Polyester, Polyethylene (PE), Polyetherketoneketone, Polyetherimide, Polyethersulfone, Polysulfone, Chlorinated Polyethylene, Polylactic acid (PLA), Polymethylmethacrylate, Polymethylpentene, Polyphenylene, Polyphenylene oxide, Polyphenylene sulfide, Polyphthalamide, Polypropylene (PP), Polystyrene, Polysulfone, Polytrimethylene terephthalate, Polyurethane, Polyvinyl acetate, Polyvinyl chloride (PVC), Polyvinylidene chloride, and Styreneacrylonitrile, Nylon (aliphatic or aromatic polyamide) or the combinations thereof.

[0092] Preferably the thermoplastic polymer is Acrylonitrile butadiene styrene (ABS), Polylactic acid (PLA), Nylon (aliphatic or aromatic polyamide), Polypropylene (PP), Polyethylene (PE), Polyethylene terephthalate (PET) and Polycarbonate (PC), most preferably Polylactic acid.

[0093] The polylactic acid) PLA occurs as racemates D-racemate (PDLLA) and L-racemate (PLLA).

[0094] In one embodiment the PLA is a mixture D- and L-racemates; D-racemate; or L-racemate, preferably L-racemate.

[0095] Also, any suitable thermoplastic elastomers can be used instead or in combination with the thermoplastic polymer. Thermoplastic elastomers (TPE), sometimes referred to as thermoplastic rubbers, are a class of copolymers or a physical mix of polymers (usually a plastic and a rubber), which consist of materials with both thermoplastic and elastomeric properties. In one embodiment is thermoplastic elastomer is a styrenic blockcopolymer (TPS), in another embodiment the thermoplastic elastomer is a thermoplastic polyolefin elastomer (TPO), in yet another embodiment the thermoplastic elastomer is a thermoplastic vulcanizate (TPV), a thermoplastic polyurethane (TPU), a thermoplastic copolyester (TPC), a thermoplastic polyamide (TPA), a non-classified thermoplastic elastomer (TPZ) or a mixture of any known thermoplastic elastomers.

[0096] The detonation nanodiamond can be any suitable nanodiamond known in the art.

[0097] In one embodiment the detonation nanodiamond is mono-functionalized nanodiamond. The detonation nanodiamonds may be mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups.

[0098] Preferably the detonation nanodiamonds are substantially mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups, preferably are mono-functionalized with either amine, carboxylic acid, hydrogen or hydroxyl groups.

[0099] In one embodiment the detonation nanodiamonds are substantially amine functionalized. In another embodiment the detonation nanodiamonds are substantially carboxylic acid functionalized. In other embodiment the detonation nanodiamonds are substantially hydrogen functionalized. Yet, in other embodiment the detonation nanodiamonds are substantially hydroxyl functionalized. In another embodiment the detonation nanodiamonds are functionalized substantially with any other anionic, cationic or neutral functional groups.

[0100] Such detonation nanodiamonds are commercially available or can be produced with known methods.

[0101] In one embodiment the detonation nanodiamonds exhibit zeta potential higher than +30 mV, preferably higher than +40 mV and more preferably higher than +50 mV. The zeta potential is measured from 0.5 wt % aqueous nanodiamond dispersion at pH 7.

[0102] In another embodiment the detonation nanodiamonds exhibit zeta potential value more negative than −30 mV, preferably more negative than −40 mV and more preferably more negative than −50 mV. The zeta potential is measured from 0.5 wt % aqueous nanodiamond dispersion at pH 7.

[0103] In one embodiment D90 particle size distribution (as measured from 0.5 wt. % nano-diamond dispersion) is less than 15 nm, preferably from 2 nm to 15 nm, more preferably, from 2 nm to 10 nm.

[0104] The item may additionally comprise at least one filler other than detonation nanodiamond selected from a group consisting of metal, metal oxide, metal nitride, metal carbide, carbon compound, silicon compound, boron compound such as boron nitride, ceramic materials, natural fibers or the combinations thereof. The carbon compound can be selected from diamond material other than detonation diamond, graphite, carbon black, carbon fiber, graphene, oxidized graphene, carbon soot, carbon nanotube, pyrolytic carbon, silicon carbide, aluminum carbide, carbon nitride, or the combinations thereof.

[0105] The item can be transparent or substantially transparent. The item may also comprise a coloring agent, to make the item available in desired color.

[0106] The use of nanodiamond fillers will enable better layer to layer adhesion by improving the 3D printed item tensile strength but also thermal properties such as thermal conductivity and glass transition temperature. The use of nanodiamond fillers will also improve 3D printed item compression strength properties. Improved thermal properties will widen the applicable operational temperature window of 3D printed items, i.e. to prevent 3D printed item softening at a temperature wherein the 3D printed item would already soften if printed from nanodiamond not containing 3D printing filaments. Nanodiamond enhanced thermoplastic material properties will also allow the use of thermoplastic materials not applicable within 3D printing today but if facilitated, would be beneficial for a range of industrial products and applications.

[0107] The present invention further provides a method for making 3D printed item, the method comprising: [0108] melting a filament comprising thermoplastic material in an amount ranging 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt % in printing head of a 3D printer; and [0109] depositing the molten material in a 3D printer in successive layers to form a 3D printed item.

[0110] The present invention further provides a use of 3D printed item comprising thermoplastic polymer in amount ranging from 80 wt % to 99.99 wt % and detonation nanodiamonds in an amount ranging 0.005 wt % to 10 wt %, wherein the item has at least 15% higher tensile strength compared to said item without detonation nanodiamonds. The use of 3D printed item according to the present invention may be but is not limited to within automotive including E-mobility, aerospace, electronic devices, bicycles, household goods, industrial components, military components, polymeric components to replace current metallic components, molds, medical devices and artificial bone replacement materials, water purification devices and structures, decorative items, components and structures applied in chemicals manufacturing and agricultural devices. The present invention further provides manufacturing and use of more complex structures than would be available without said nanodiamond additives. Such structures may thus enable manufacturing components not possible to manufacture with conventional injection molding or components that have to currently be manufactured from metals or metal composites. Today, such structures may also have to be produced from several components but can now be 3D printed as one sole component, resulting in significant savings in manufacturing cost but allowing also Design Freedom, i.e. manufacturing of components with dimensions and or size not possible to manufacture with the current technologies.

[0111] Hereafter, the present invention is described in more detail and specifically with reference to the examples, which are not intended to limit the present invention.

EXAMPLES

[0112] Materials

[0113] The applied nanodiamond material was Carbodeon Ltd Oy produced uDiamond Amine D dispersion in water (0.5 wt. % nanodiamond content). Said material zeta potential exceeds+50 mV and applied product lot particle size distribution (as measured from 0.5 wt. % nano-diamond dispersion) was less than 15 nm (D90). The degree applied nano-diamond material amine surface termination was determined by measuring the nanodiamond material contained surface nitrogen with Kjeldahl method and exceeded the specified value of 2000 mg/kg of nanodiamonds. Particle size and zeta potential measurements were carried out with Malvern Zetasizer Nano ZS tool.

[0114] The applied thermoplastic material was Bioplast 2202 PLLA grade, supplied by Corbion Plastic, as standard 3 mm granules.

[0115] Analyses

[0116] The tensile strength measurements were carried out with Zwck Roell 250 KN tensile strength testing apparatus, by TU Delft Aerospace Department. The measurements were carried out at 19.5° C. temperature, by applying ISO 527 standard.

[0117] Alternatively, the tensile strength analyses as well as Young's Modulus and Elongation at break have been carried out by VTT Finland, applying ISO 527 standard. Bending Modulus and Bending Strength have been analysed by VTT Finland, applying ISO 178 standard. Impact strength and Impact strength, Scharpy notched (23° C.) have been VTT Finland, applying ISO 179 standard.

[0118] Manufactured ND enhanced PLA compounds density (ISO 1183), glass transition temperature, melting temperature (DSC), HDT B value (0.45 MPa, flatwise), HDT B value (0.45 MPa, flatwise, annealed (ISO 75) as well as thermal conductivities (hot disk method) have been analysed by VTT Finland.

[0119] Manufactured filaments moisture content was analysed by thermogravimetric method, by VTT Finland.

[0120] Processing to Manufacture the Reference Bioplast 2202 PLLA Sample Filaments and 0.05 wt. % Amine-Terminated Nanodiamond Filled Bioplast 2202 PLLA Sample Filaments

[0121] Bioplast 2202 PLLA Pellets Pre-Drying

[0122] 3 kg's of 3 mm Bioplast 2202 PLLA pellets were dried in a 5-liter precision scientific vacuum oven, at 21-25 Inch of mercury (inHg) vacuum and at 62-67° C. temperature, in four-hour intervals over 24 hours period, processing one kg of thermoplastic material at a time.

[0123] 0.05 wt. % Amine-Terminated Nanodiamond—Bioplast 2202 PLLA Pellets Mixing and Drying

[0124] 100 g of 0.5 wt. % uDiamond Amine D aqueous nanodiamond dispersion (corresponding to 0.5 g of nanodiamond particles) was diluted with 900 grams of de-ionized water, followed by mixing resulting diluted nanodiamond dispersion with 999.5 grams of pre-dried 3 mm Bioplast 2202 PLLA pellets. In order to reach even distribution of nanodiamond particles onto PLLA pellets surfaces, the resulting mixture was agitated gently with a mechanical mixer and left to stabilize over a 24 hours period. The resulting nanodiamond dispersion PLLA pellet mixture was then placed in a 5-liter precision scientific vacuum oven, at 21-25 Inch of mercury (inHg) vacuum and at 62-67° C. temperature, in four-hour intervals over 24 hours period, to result in dried Bioplast 2202 PLLA pellets with 0.05 wt. % of amine-terminated nanodiamonds coated evenly on PLLA pellets surfaces.

[0125] Compounding and Filament Manufacturing

[0126] Bioplast 2202 PLLA Reference Filament Sample

[0127] One kg of pre-dried, 3 mm Bioplast 2202 PLLA pellets were compounded with a Nortek high temperature XT one heat zone single screw extruder, applying a 1.75 mm nozzle made out of brass, with an additional in-line heat band to achieve a 10 cm flow section. The applied compounding temperature was set to 220° C., in an environment of 10° C.

[0128] The produced filament was cooled by air and no filament winder was applied but was collected to a table next to extruder. Under these conditions, the extruder throughput is 1 kg/h. The produced, ready to use Bioplast 2202 PLLA filament material comprised a size of 1.75 with ±0.2 mm size deviation.

[0129] Additional nanodiamond enhanced PLA based filament samples comprising both 1.75 mm and 2.85 mm diameter sizes were manufactured by Dutch Filament, Helmond, The Netherlands; applying their commercial filament production lines. The produced filaments were packaged in sealed and vacuumised aluminium bags containing a desiccant bag. The applied nanodiamond material was Carbodeon produced amine terminated nanodiamond particles exhibiting a zeta potential of +50 mV or higher. The filament product nanodiamond concentration was between 0.04 and 0.1 wt. % and no significant difference in key mechanical or thermal properties were detected between applied nanodiamond concentrations.

[0130] 0.05 wt. % Amine-Terminated Nanodiamond Filled Bioplast 2202 PLLA Filament Sample

[0131] 500 g of dried, 3 mm 0.05 wt. % amine-terminated nanodiamond coated Bioplast 2202 PLLA pellets were compounded with a Nortek high temperature XT one heat zone single screw extruder, applying a 1.75 mm nozzle made out of brass, with an additional in-line heat band to achieve a 10 cm flow section. The applied compounding temperature was set to 220° C., in an environment of 10° C.

[0132] The produced filament was cooled by air and no filament winder was applied but was collected to a table next to extruder. Under these conditions, the extruder throughput is 1 kg/h. The produced, ready to use 0.05 wt. % amine-terminated nanodiamond Bioplast 2202 PLLA filament material comprised a size of 1.75 with ±0.2 mm size deviation.

[0133] 3D Printing of Sample Specimen

[0134] The sample specimens were prepared with an Ultimaker 2+ 3D printer. The applied design file was scaled and adjusted 1B tensile ‘dogbone’ downloaded from an open source community Thngiverse.com. The conversion of said file was done with Cura program available from Ultimaker. The design file for all samples was held constant. The code file used to print the piece was held constant across all samples, consisting of 2 perimeter walls and a 45 by 45 degree diagonal infill pattern.

[0135] Results

[0136] The tensile strength was measured from two Bioplast 2202 PLLA 3D-printed reference samples and from two 0.05 wt. % amine-terminated nanodiamond-Bioplast 2202 PLLA 3 D printed samples, as depicted in Table 1.

TABLE-US-00001 TABLE 1 Tensile strength measurements. Specimen L.sub.0 F.sub.max a.sub.0 b.sub.0 S.sub.0 Tensile Strength ID mm N mm mm mm.sup.2 Tensile Strength Reference 1 30.09 345.6556396 1.3 9.44 12.272 28.16620271 Mpa Reference 2 30.115 345.7418518 1.52 9.4 14.288 24.19805794 Mpa 0.05 wt. % ND 30.125 826.7680054 2.4 9.47 22.728 36.37662818 Mpa 0.05 wt. % ND 30.185 626.3701782 1.89 9.23 17.4447 35.90604471 Mpa

[0137] The two PLLA reference samples average tensile strength is 26.182. The two nanodiamond enhanced average tensile strength is 36.142. Hence, the 0.05 wt. % amine-terminated nanodiamond containing 3D printed PLLA material tensile strength was improved by 38%.

[0138] In another set of trials with a similarly manufactured amine-terminated nanodiamond containing PLLA filament with nanodiamond concentration of 0.07 wt. %, the tensile strength (at max load) of a printed specimen was 43.5 MPa, resulting in over 60% improvement in tensile strength property. Here, and in all the printed and analysed specimen below, all testing specimens were printed by Mass Portal SIA, Riga, Latvia; using Mass Portal Pharaoh XD20 (SN: 150633) under the following conditions: printing temperature=270° C., printing speed=60 mm/s, heat bed temperature 30° C.

[0139] Young's Modulus of an amine-terminated nanodiamond containing PLLA filament with 0.07 wt. % nanodiamond content was measured to 6240 MPa. Young's Modulus of an amine-terminated nanodiamond containing PLLA filament with 0.05 wt. % nanodiamond content was measured to 6350 MPa. Young's Modulus of the reference PLLA filament printed sample specimen was 4690 MPa.

[0140] Bending Modulus (Flexural Young's Modulus) of 3D printed specimen manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA filament was measured to 5446 MPa (ISO 178, method A; deviation 53.73 MPa). The reference PLLA material printed specimen bending modulus was measured to be 4030 MPa (deviation 20.47).

[0141] Bending strength (Flexural Young's strength; stress at yield; ISO 178, method A) of 3D printed specimen manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA filament was measured to 80.3 MPa with standard deviation of 0.56 MPa. The reference PLLA material printed specimen bending strength was measured to 71.47 MPa, with standard deviation of 0.19 MPa.

[0142] The elongation at break of 3D printed specimen manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA filament was measured to 3.2% (ISO 527). The reference PLLA material printed specimen elongation at break was measured to 1.8%.

[0143] The Charpy impact strength (notched, ISO 179) of 3D printed specimen (2 perimeter sample) manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA filament was measured to 2.2 kJ/m.sup.2 (standard deviation 0.12). The Charpy impact strength (notched) of 3D printed specimen (5 perimeter sample) manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA filament was measured to 2.5 kJ/m.sup.2 (standard deviation 0.07). The Charpy impact strength (notched) of 3D printed specimen (5 perimeter sample) manufactured from reference PLLA filament was measured to 2.2 kJ/m.sup.2 (standard deviation 0.1).

[0144] The heat deflection temperature (HDT B, 0.45 MPa, flatwise; ISO 75) of filament manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA was measured to 107.2° C. (standard deviation 7.92° C.). The heat deflection temperature (HDT B, 0.45 MPa, flatwise; ISO 75) of filament manufactured from reference PLLA was measured to 93.7° C. (standard deviation 7.24° C.).

[0145] The heat deflection temperature (HDT B, 0.45 MPa, flatwise, annealed; ISO 75) of filament manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA was measured to 125.1° C. (standard deviation 3.9° C.). The heat deflection temperature (HDT B, 0.45 MPa, flatwise, annealed; ISO 75) of filament manufactured from reference PLLA was measured to 116.1° C. (standard deviation 6.55° C.). For the annealed samples the annealing was conducted at 110° C./1 h followed by a cooling phase (samples were taken out of from the oven when the temperature reached 27° C. after 2 h 15 minutes cooling). The samples were stored in environmentally controlled room until the measurements.

[0146] The moisture content of a 1.75 mm diameter filament manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA stored in a vacuumed, closed aluminium bag with desiccant (the filament product manufactured Dutch Filament, Helmond, the Netherlands) was analysed by thermogravimetric method by VTT Finland. The filament moisture content was measured to 0.1 wt. %. If kept 24 hours in controlled environment, the filament moisture will elevate to 0.15 wt. %. Subsequent drying for 20 h at 50° C. will reduce the moisture into 0.02 wt. %.

[0147] The melting temperature of filament manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA was measured by to 171.6-182° C. (DSC, 10° C./min). The melting temperature of filament manufactured from reference PLLA was measured by to 170.5-182.3° C. (DSC, 10° C./min).

[0148] The glass transition temperature of filament manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA was measured by to 49.7° C. (DSC, 10° C./min). The glass transition temperature of filament manufactured from reference PLLA was measured by to 44.4° C. (DSC, 10° C./min).

[0149] The thermal conductivity of filament manufactured from 0.05 wt. % amine-terminated nanodiamond containing PLLA was measured by to 0.38 W/m.Math.K, by hot disk method.