Carbon black containing thermally conductive polymer composition and polymer precursor composition, masterbatch and product

Abstract

Composite polymer composition, comprising: a polymer matrix; and a partially crystallized carbon black dispersed in the polymer matrix at a concentration of 12 to 28 wt%, wherein the carbon black has an OAN structure of more than 120 cm 3 / 100g and less than 200 cm 3 / 100g, a surface energy of less than 8 mJ / m 2 , a percentage crystallinity of less than 65% and a microcrystalline Raman surface area (L) a ) of more than or equal to 28 Å, where the carbon black is produced by thermal treatment of a furnace black at a temperature of more than 700°C and less than 1800°C.

Description

Area of ​​Revelation

[0001] The present disclosure relates to polymer compositions and, in particular, to plastics having improved thermal conductivity and improved mechanical properties. background

[0002] Polymer systems that can benefit from improved heat transfer are used in a variety of fields, including electronics, mechanical, automotive, aerospace, and industrial applications. For example, conductive polymers can be used in wire and cable jackets to dissipate heat from the cable core. Thermally conductive polymers can also replace materials such as metals or less thermally conductive materials typically used in applications requiring efficient heat transfer. Summary

[0003] In an article, a composite polymer composition is provided, the composite polymer composition comprising: a polymer matrix and a partially crystallized carbon black dispersed in the polymer matrix at a concentration of 12 to 28 wt.%, the carbon black having an OAN structure of more than 120 cm 3 / 100g and less than 200 cm 3 / 100g, a surface energy of less than 8 mJ / m 2 , a percent crystallinity of less than 65% and a microcrystalline Raman area size (L a) of greater than or equal to 28 Å. The partially crystallized carbon black is prepared by thermal treatment of a furnace black at a temperature of greater than 700°C and less than 1800°C. The composition may comprise a copolymer or terpolymer. The polymer composition may comprise a polyolefin, a polystyrene, a polycarbonate, a polyamide and / or a polyamine. The carbon black may have a microcrystalline Raman area size (L a ) of more than or equal to 35 Å and a surface energy of more than 1 mJ / m 2The polymer can be selected from thermoplastic polyolefins (TPO), polyethylene (PE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), ultra-high molecular weight polyethylene (UHMWPE), very low-density polyethylene (VLDPE), metallocene medium-density polyethylene (mLLDPE), polypropylene, polypropylene copolymers, ethylene-propylene rubber (EPR), ethylene-propylene-diene terpolymers (EPDM), acrylonitrile-butadiene-styrene (ABS), acrylonitrile EPDM styrene (AES), styrene-butadiene-styrene (SBS), polyoxymethylene (POM), polyamides (PA), polyvinyl chloride (PVC), tetraethylene-hexapropylene-vinylidene fluoride polymers (THV), perfluoroalkoxy polymers (PFA), polyhexafluoropropylene (HFP), Polyketones (PK), ethylene-vinyl alcohol (EVOH), copolyesters, polyurethanes (PU), thermoplastic polyurethanes, polystyrene (PS), polycarbonate (PC), polybutylene terephthalate (PBT),Polyethylene terephthalate (PET), polyphenylene oxide (PPO), polyphenylene ether (PPE). The composition can be a masterbatch. The composition can further comprise a non-carbonaceous particle with a thermal conductivity of more than 30 W / mK, for example, boron nitride, magnesium oxide, zinc oxide, and aluminum oxide. The volume ratio of the partially crystallized carbon black to the non-carbonaceous particle, for example, boron nitride, can be from 1:1 to 1:10. The composite polymer composition can have a thermal conductivity that is at least 1.6 times greater, at least 1.7 times greater, or 2-4 times greater than the thermal conductivity of the polymer matrix. The partially crystallized carbon black can improve the thermal conductivity of the composite polymer composition by at least 10% relative to an untreated carbon black.

[0004] In another aspect, a polymer precursor composition is provided, the composition comprising: a polymer precursor comprising a polymerizable monomer or oligomer and a partially crystallized carbon black dispersed in the monomer or oligomer at a concentration of 12 to 28 wt.%, wherein the carbon black has an OAN structure of greater than 120 cm 3 / 100g and less than 200 cm 3 / 100g, a surface energy of less than 8 mJ / m 2 and a percentage crystallinity of less than 65% and a microcrystalline Raman area size (L a) of greater than or equal to 28 Å. The partially crystallized carbon black is produced by thermal treatment of a furnace black at a temperature of greater than 700°C and less than 1800°C. The polymer precursor may be a precursor of a polymer selected from a polyolefin, a polystyrene, a polycarbonate, a polyamide, and / or a polyamine. The polymer precursor may be a precursor of a polymer selected from thermoplastic polyolefins (TPO), polyethylene (PE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ultra-high molecular weight polyethylene (UHMWPE), very low density polyethylene (VLDPE), metallocene medium density polyethylene (mLLDPE), polypropylene, polypropylene copolymers, ethylene-propylene rubber (EPR), ethylene-propylene-diene terpolymers (EPDM), acrylonitrile-butadiene-styrene (ABS), acrylonitrile EPDM styrene (AES),Styrene-butadiene-styrene (SBS), polyoxymethylene (POM), polyamides (PA), polyvinyl chloride (PVC), tetraethylene-hexapropylene-vinylidene fluoride polymers (THV), perfluoroalkoxy polymers (PFA), polyhexafluoropropylene (HFP), polyketones (PK), ethylene-vinyl alcohol (EVOH), copolyesters, polyurethanes (PU), thermoplastic polyurethanes, polystyrene (PS), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphenylene oxide (PPO), and polyphenylene ether (PPE). The polymer precursor can be a precursor of a polymer selected from the group consisting of acrylics, epoxies, silicones, phenolic resins, polyimides, plastisols, and polyvinyl acetates. The polymer precursor may comprise a precursor of a polyolefin, a polystyrene, a polycarbonate, a polyamide, and / or a polyamide. The composition may further comprise a non-carbonaceous particle having a thermal conductivity of more than 30 W / mK, for example, boron nitride, magnesium oxide,Zinc oxide and aluminum oxide. The volume ratio of the partially crystallized carbon black to the non-carbonaceous particle, for example, boron nitride, can be from 1:1 to 1:10. The polymer precursor composition can have a thermal conductivity after polymerization that is at least 1.6 times greater, at least 1.7 times greater, or 2-4 times greater than the thermal conductivity of a polymer of the polymer precursor composition. The partially crystallized carbon black can improve the thermal conductivity of a polymer of the polymer precursor composition by at least 10% relative to an untreated carbon black.

[0005] In another aspect, the composite polymer composition or the polymer precursor composition may comprise a carbon black having a microcrystalline Raman area size (L a) of more than 29, 30, 31 or 35 Å and / or less than 65, 60, 55, 50 or 45 Å. The surface energy of the carbon black may be less than 4, less than 3 or less than 2 mJ / m 2 and / or more than 0 mJ / m 2 The carbon black may have a percentage crystallinity of greater than or equal to 35%, 40%, 45%, 50%, 55%, or 60%. The BET surface area of ​​the carbon black may be less than 425 + / - 25, less than 300, less than 250, from 40 to 400 m 2 / g, from 46 to 400 m 2 / g, from 40 to 300 m 2 / g or from 40 to 200 m 2 / g. The composite polymer composition or the polymer precursor composition can be used to manufacture products such as wire and cable sheathing, 3D printing products, automotive parts, and LED housings and devices. The carbon black can have a substantially polyhedral primary particle shape and can have an iodine number of less than 425 m 2 / g, less than 350 mg / g, less than 300 mg / g, less than 250 mg / g, or less than 200 mg / g. The carbon may be an unmodified carbon black. The composite polymer composition or the polymer precursor composition may contain a second carbon black, which may or may not be partially crystallized. The partially crystallized carbon black may be obtained by increasing a microcrystalline Raman area size (L a ) of a base carbon black by more than 5, more than 10, more than 15 or more than 20 Å. Character list Fig. Figure 1 shows a bar chart comparing the thermal conductivity of a base carbon black with two embodiments of a partially crystallized carbon black derivative; Fig. Figure 2 shows a bar chart comparing the thermal conductivity of a second base carbon black with three embodiments of a partially crystallized carbon black derivative; Fig. 3 shows a bar chart comparing the thermal conductivity of a third base carbon black with an embodiment of a partially crystallized carbon black derivative; Fig. 4 shows a bar chart comparing the thermal conductivity of a fourth base carbon black with an embodiment of a partially crystallized carbon black derivative; Fig. 5 shows a bar chart comparing the thermal conductivity of a fifth base carbon black with an embodiment of a partially crystallized carbon black derivative; Fig. Figure 6 provides a graph showing the thermal conductivity of three polymer composites, each containing a different filler; Fig. 7 provides a graph showing the thermal conductivity of the polymer composites from Fig.6, as well as the thermal conductivity of two comparative examples, both containing boron nitride and carbon black particles; Fig. 8 provides a graph showing the thermal conductivity of the polymer composites made of Fig. 7, as well as a third embodiment of a polymer composite containing a highly thermally conductive particle and a partially crystallized carbon black particle. Detailed description

[0006] In one article, a polymer system is provided comprising at least one polymer and at least one partially crystallized carbon black. Partially crystallized (also referred to as partially graphitized) carbon blacks exhibit higher crystallinity and lower surface energy than their corresponding base carbon blacks and, as described below, can provide improved heat transfer capabilities compared to the less crystallized form of carbon black. As illustrated herein, the partially crystallized carbon blacks can also improve the rheology of the polymer precursors in which they are dispersed compared to similar systems employing conventional carbon blacks. The polymer systems described herein can be any synthetic polymer in which a partially crystallized carbon black can be dispersed to improve heat transfer efficiency.Additionally, it has been found that carbon blacks subjected to excessive crystallization do not provide improved thermal conductivity properties compared to less crystallized carbon blacks. Thus, both insufficient and excessive graphitization may not exhibit the thermal conductivity benefits of the carbon blacks according to the embodiments disclosed herein.

[0007] The polymer compositions included both cured polymers and pre-polymer compositions. As used herein, a "polymer" or "polymer matrix" is in the form of a polymer composition after polymerization and may be suitable for use as a masterbatch, compound, or otherwise in the manufacture of articles, for example, plastic articles. As used herein, a "pre-polymer" is a polymer composition consisting of as yet unpolymerized monomers and oligomers. The polymers may be polymers cured by methods known in the art, including heat, radiation, solvent evaporation, chemical catalysis, and vulcanization. The polymers may be based on one-, two-, three-, or more-part pre-polymer systems. A "polymer composite" or "polymeric composite" is a material that includes at least one polymer and a second separate component.The second component of the composite may be particles, fibers, pigments, or a second polymer, wherein the second polymer is different and not homogeneously mixed with the first polymer.

[0008] In some embodiments, the polymer(s) may be a thermoplastic polymer and a thermosetting polymer. The polymer system may be a plastic. These plastic systems may be selected from those that are molded, extruded, coated, rolled, and otherwise formed into polymer components. Furthermore, the polymer group may be a homopolymer, copolymer, terpolymer, and / or a polymer containing one, two, three, or more different repeating units. Furthermore, the polymer group may be any type of polymer group, such as a random polymer, alternating polymer, graft polymer, block polymer, star polymer, and / or comb-like polymer. The polymer group may also be one or more polymer blends. The polymer group may be an interpenetrating polymer network (IPN), a simultaneously interpenetrating polymer network (SIN), or an interpenetrating elastomeric network (IEN).

[0009] Specific examples of the polymers include, but are not limited to, linear high polymers such as polyethylene, poly(vinyl chloride), polyisobutylene, polystyrene, polycaprolactam (nylon), polyisoprene, and the like.Other general classes of polymers suitable for use include polyamides, polycarbonates, polyelectrolytes, polyesters, polyethers, epoxies, polyanhydrides, (polyhydroxy)benzenes, polyimides, polymers containing sulfur (such as polysulfides, (polyphenylene)sulfide and polysulfones), polyolefins, polymethylbenzenes, polystyrene and -styrene copolymers (including ABS), acetal polymers, acrylic polymers, acrylonitrile polymers and copolymers, polyolefins containing halogen (such as polyvinyl chloride and polyvinylidene chloride), fluoropolymers, ionomeric polymers, polymers containing one or more ketone groups, liquid crystal polymers, polyamide-imides, polymers containing olefin double bonds (such as polybutadiene and polydicyclopentadiene), polyolefin copolymers, polyphenylene oxides, polysiloxanes, poly(vinyl alcohols), polyurethanes, thermoplastic elastomers and the like.In some embodiments, the polymer is a polyolefin, a polyurethane, a polystyrene, a polyacrylate, a polyamide, a polyester, and blends thereof. Particularly suitable polymers include polyolefins and polyamides.

[0010] In certain embodiments, the polymer may be, for example, a polyolefin, a vinyl halide polymer, a vinylidene halide polymer, a perfluorinated polymer, a styrene polymer, an amide polymer, a polycarbonate, a polyester, a polyphenylene oxide, a polyphenylene ether, a polyketone, a polyacetal, a vinyl alcohol polymer, or a polyurethane. Suitable polymers or resins include PET or polyethylene terephthalate, polystyrene, PBT or polybutylene terephthalate and PBT alloys, polypropylenes, polyurethanes, styrene-acrylonitrile copolymer, ABS or acrylonitrile-butadiene-styrene terpolymer, PVC or polyvinyl chloride, polyesters, polycarbonates, PP / PS or polypropylene-polystyrene alloys, nylon, polyacetal, SAN or styrene-acrylonitrile, acrylics, cellulose, polycarbonate alloys, and PP or propylene alloys. Other combinations of these materials may be used.

[0011] Various polymers can be combined with partially crystallized carbon blacks to form composite polymers. The composite polymers can be thermoplastic polyolefins (TPO), polyethylene (PE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ultra high molecular weight polyethylene (UHMWPE), very low density polyethylene (VLDPE), metallocene medium density polyethylene (mLLDPE), polypropylene, polypropylene copolymers, ethylene-propylene rubber (EPR), ethylene-propylene-diene terpolymers (such as EPDM), acrylonitrile butadiene styrene (ABS), acrylonitrile EPDM styrene (AES), styrene-butadiene-styrene (SBS), polyoxymethylene (POM), polyamides (PA, such as PA6, PA66, PA11, PA12 and PA46), polyvinyl chloride (PVC), tetraethylene hexapropylene vinylidene fluoride polymers (THV), Perfluoroalkoxypolymers (PFA), Polyhexafluoropropylene (HFP), Polyketones (PK), Ethylene Vinyl Alcohol (EVOH), Copolyesters,Polyurethanes (PU), thermoplastic polyurethanes, polystyrene (PS), polycarbonates (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphenylene oxides (PPO), and polyphenylene ethers (PPE). Specific blends include PC / ABS, PC / PBT, PP / EPDM, PP / EPR, PP / PE, PA / PPO, and PPO / PE. The polymer compositions can be optimized to achieve the desired overall properties, such as injection molding, conductivity, toughness, stiffness, smoothness, and tensile properties. The foregoing list is not intended to be exhaustive, but merely illustrates the various materials that can be used. Polymer blends containing one or more of these polymer materials, with the described polymers present either as a major or minor component,can also be used. The specific type of polymer may depend on the desired application. Specific examples of the polymers are described in detail below.

[0012] In general, the polymer groups described in Volume 18 of the Encyclopedia of Chemical Technology, KIRK-OTHMER, (1982), pages 328 to 887 and in Modern Plastics Encyclopedia ,98, pages B-3 to B-210 and in "Polymers: Structure and Properties," by C.A. Daniels, Technomic Publishing Co., Lancaster, Pa. (1989), all of which are incorporated by reference in their entirety, can be used as the polymer(s). The polymers can be prepared in a variety of different ways, and these methods are known to those skilled in the art. The above references, the KIRK-OTHMER section, Modern Plastics Encyclopedia, and the C.A. Daniels reference, provide methods by which these polymers can be prepared.

[0013] The polymer compositions of the present disclosures may also contain suitable additives for their known purposes and in known amounts. For example, the compositions may contain additives such as crosslinking agents, vulcanizing agents, stabilizers, pigments, dyes, colors, metal deactivators, oil extenders, lubricants, and / or inorganic fillers, and the like, along with other additives described elsewhere herein. In some embodiments, the composite may contain additional particulate particles intended to increase thermal conductivity. In many embodiments, carbon black is the only particulate matter included, and the polymer composite may not contain any other particulate matter. In some embodiments, the carbon black may comprise more than 50 wt. %, more than 75 wt. %, or more than 95 wt. % of the particulate matter in the polymer composite.

[0014] The polymer compositions can be prepared using conventional methods, such as mixing the various components with commercially available mixers. The composition can be prepared by batch or continuous mixing processes as known in the art. For example, devices such as discontinuous internal mixers, continuous internal mixers, reciprocating single-screw extruders, twin-screw and single-screw extruders, etc., can be used to mix the components of the compositions. Carbon black can be added to one or more of the components of a multi-part polymer system and can be present in the same or different concentrations in each of the components. For example, in a two-part epoxy system, the carbon black can be blended into the epoxy resin, the crosslinking agent, or both.In copolymers and terpolymers, partially crystallized carbon black can be incorporated into one, some, or all of the prepolymer components. The concentration of partially crystallized carbon black in each component can, in some cases, be varied to adjust the viscosity of the various components or otherwise improve the blending of the components. Partially crystallized carbon black can also be used in a polymer blend. As used herein, a polymer blend is a homogeneous mixture of two or more different polymers and is distinct from a copolymer and a terpolymer. Partially crystallized carbon blacks can also be incorporated directly into a polymer blend prior to curing or can be incorporated into one or more of the polymer precursors prior to blending with a second polymer precursor.Partially crystallized carbon blacks can also be incorporated into a masterbatch, which, prior to curing, is used as a carrier for subsequent blending into a similar or different polymer system. In a masterbatch, the concentration of partially crystallized carbon black can be significantly higher (e.g., at least 2x, at least 3x, at least 4x, at least 2x, and 10x, for example, from 3x to 8x, or from 2x to 6x) than in the resulting composite polymer composition. The composite polymer compositions containing partially crystallized carbon black can be blended and formed into pellets for future use in the manufacture of materials such as articles for automotive applications.

[0015] Partially crystallized carbon blacks can be formed by increasing the crystallinity of a base furnace (untreated) carbon black without complete crystallization of the particles. Base furnace blacks exhibit native crystallinity with a typical microcrystalline Raman area (L a) in the range of 16 to 21 Å. In one set of embodiments, the base carbon blacks are partially crystallized by controlled heat treatment of a base carbon black. A carbon black is "heat treated or processed" or "thermally treated or processed" when it is subjected to a secondary heat treatment (after initial particle production) that alters the crystallinity, surface energy, and morphology of the carbon black particle. Crystallization of the carbon black particle may also change the shape of the primary particles, for example, from a substantially spherical to a more (but not necessarily perfect) polyhedral shape.

[0016] Partially crystallized furnace carbon blacks can be formed from readily available furnace carbon blacks. Suitable base carbon blacks that can be used, provided that base carbon blacks to be used in the present invention are furnace carbon blacks, include: VULCAN® XC72, VULCAN® XC72R, and VULCAN® XC500 carbon blacks and other carbon blacks available under Regal®, Black Pearls®, Spheron®, CSX™, Vulcan®, and Sterling® from Cabot Corporation. Other carbon blacks such as KETJEN® EC ​​300 and KETJEN® EC ​​600 carbon blacks, available from AkzoNobel; PRINTEX® XE carbon black, from Evonik; Ensaco® 350 carbon black, from TIMCAL; Raven®, XT Technology, Ultra®, and other carbon blacks available from Birla Carbon; the Corax®, Durex®, Ecorax®, Sable™ and Purex® brands and the CK line available from Orion Engineered Carbons; SA, and Chezacarb® B Carbon Black from Unipetrtol RPA (Unipetrol Group) can also be used as base carbon blacks, provided that they are furnace carbon blacks to be used according to the invention.

[0017] A measure of crystallinity is the microcrystalline Raman area. Raman measurements of L a (microcrystalline area) are based on Gruber et al., "Raman Studies of Heat-Treated Carbon Blacks," Carbon Volume 32 (7), pages 1377-1382, 1994, which is incorporated herein by reference. The Raman spectrum of carbon includes two major "resonance bands" at approximately 1340 cm -1 and 1580 cm -1 , which are called "D" and "G" bands, respectively. It is generally assumed that the D band corresponds to the disordered sp 2 -carbon and the G-band on graphitic or “ordered” sp 2 -carbon. Using an empirical approach, the ratio of the G / D bands and the La , measured by X-ray diffraction (XRD), are highly correlated and the regression analysis yields the empirical relationship: La=43.5×(Area of ​​G band / Area of ​​D band) where L a in Angstroms. Therefore, a higher L a -value of a more ordered crystalline structure. Crystallinity can also be measured by X-ray diffraction (XRD).

[0018] In one manufacturing process, a heat-treated carbon black may be produced in a tube furnace or other suitable heating device. The furnace may be heated electrically or by combustion of fossil fuels. The temperature of the carbon black bed may be constant throughout to ensure that all of the carbon black is exposed to the same reaction conditions. The carbon black bed may be static or fluidized. Samples may be exposed to specific temperatures, such as those specified below, for a period of time sufficient to achieve, but not exceeding, the desired partial crystallinity. Samples may be heat-treated in an inert environment, and an inert gas, such as nitrogen, may be passed through or over the carbon black to assist in the removal of volatiles emanating from the carbon black.By taking samples at different time intervals, an operator can analyze the samples and accurately determine the degree of crystallinity of the carbon black. Those skilled in the art are able to take a sample of carbon black after such treatment, analyze the Raman microcrystallinity, and adjust the process accordingly to achieve, for example, a target crystallinity or surface energy. Once the time and temperature profiles have been determined for a specific base carbon black, the profile can be repeated on the specific base carbon black to reproduce partially crystallized carbon black with, for example, a desired crystallinity, surface energy, surface area, and OAN structure. Other heat treatment methods are known to those skilled in the art and can be calibrated in the same way.

[0019] In various embodiments, the carbon black particles may be exposed to temperatures greater than 700°C, greater than or equal to 800°C, greater than or equal to 1000°C, greater than or equal to 1100°C, greater than or equal to 1200°C, greater than or equal to 1300°C, greater than or equal to 1400°C, greater than or equal to 1500°C, or greater than or equal to 1600°C. In other embodiments, the carbon black particles may be exposed to temperatures of less than 800°C, less than 1000°C, less than 1100°C, less than 1200°C, less than 1300°C, less than 1400°C, less than 1500°C, less than 1600°C, less than 1700°C, or less than 1800°C. Specific temperature treatment ranges include 1000°C to less than 1800°C, 1100°C to 1700°C, 1100°C to 1600°C, 1100°C to 1500°C, 1100°C to 1400°C, and 1100°C to 1300°C. Treatment can be performed in an inert gas atmosphere, such as nitrogen.The residence time of the material at the selected temperature can be as short as milliseconds or greater than or equal to 30 minutes, one hour, two hours, or more than two hours. In some embodiments, the residence time can be limited to less than three hours, less than two hours, less than 90 minutes, less than one hour, or less than 30 minutes. The temperature can be held constant during the residence time or, in alternative embodiments, ramped up or down.

[0020] According to the invention, the partially crystallized furnace carbon black has a microcrystalline Raman area (L a ) of at least 28 Å, at least 29 Å, at least 30 Å, at least 35 Å, or at least 40 Å. In some cases, the partially crystallized furnace carbon black has a microcrystalline Raman area (L a) of 100 Å or less, 75 Å or less, 50 Å or less, 40 Å or less, 35 Å or less, or 30 Å or less. The crystallinity measured by Raman spectroscopy can also be reported using the percent crystallinity of the particle, and in some cases, the percent crystallinity can be more than 25, more than 30, more than 35, more than 37, more than 40, more than 42, or more than 50. The same sample or different samples can show a percent crystallinity of less than 65, less than 60, less than 55, less than 50, less than 45, less than 42, less than 40, less than 38, less than 35, less than 32, or less than 27.

[0021] Partial crystallization may include increasing the native microcrystalline Raman area size of the base carbon black by greater than or equal to 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, or 24 Å and / or increasing the native microcrystalline Raman area size by less than or equal to 35, 30, 25, 20, 15, or 10 Å. Similarly, the native microcrystalline Raman area size of the base carbon black may be increased by greater than or equal to 10%, 20%, 30%, 50%, 75%, 100%, 120%, or 150%. In some embodiments, the increase in the microcrystalline Raman area of ​​the base carbon black can be limited to less than or equal to 10%, 20%, 30%, 50%, 75%, 100%, 120%, or 150%. The amount of crystallization can be verified by removing the carbon black samples at various intervals and measuring the microcrystalline Raman area.

[0022] The treatment of the base carbon black can increase the microcrystalline Raman area size (L a ) by more than 5, 10, 15, 20, or 25 Å and reduce the surface energy, while limiting a reduction in the Brunauer-Emmett-Teller (BET) surface area to no more than 25%, for example, by no more than 10%, or a reduction by 1% to 25%, 5% to 25%, 10% to 25%, 1% to 10%, or 5% to 10%, relative to the BET surface area of ​​the base carbon black. Similarly, the OAN structure can be maintained, so that the partially crystallized carbon black has an OAN structure reduced by less than 5%, 10%, or 25%, compared to the base carbon black.

[0023] The surface energy (SE) of a carbon black particle can be determined by measuring the water vapor absorption with a gravimetric instrument. The carbon black sample is placed on a microbalance in a humidity chamber and balanced in a series of steps to compensate for changes in relative humidity. The mass change is recorded. The increase in equilibrium mass as a function of relative humidity is used to generate the vapor absorption isotherm. The scattering pressure (in mJ / m 2 ) for a sample is defined as π e / BET, where: πe=RT∫0p0Γdlnp and R is the ideal gas constant, T is the temperature constant, Γ is the mole of absorbed water, p0 is the vapor pressure, and p is the vapor partial pressure in each incremental step. The scattering pressure depends on the surface energy of the solid and is related to the surface energy of the solid and indicates the hydrophobic / hydrophilic properties of the solid, with a lower surface energy (SE) corresponding to higher hydrophobicity.

[0024] According to the invention, the partially crystallized furnace carbon black has a surface energy (SE) of less than 8 mJ / m 2 , 7 mJ / m 2 or less, 6 mJ / m 2 or less, 5 mJ / m 2 or less or 3 mJ / m 2 or less. In the same or other embodiments, the partially crystallized carbon black has a surface energy (SE) of more than 0 mJ / m 2 , more than 1 mJ / m 2 , more than 2 mJ / m 2, more than 3 mJ / m 2 , more than 4 mJ / m 2 , more than 5 mJ / m 2 , more than 6 mJ / m 2 , more than 7 mJ / m 2 on.

[0025] One method for measuring the surface area of ​​carbon blacks is the Brunauer-Emmett-Teller method (BET according to ASTM 6556). Various versions of the partially crystallized carbon blacks used here can achieve a BET surface area of ​​at least 100 m 2 / g, for example in the range of 100 m 2 / g up to 600 m 2 / g. In other cases, the partially crystallized carbon black has a BET of at least 200 m 2 / g, at least 300 m 2 / g, at least 400 m 2 / g, at least 500 m 2 / g or at least 600 m 2 / g. In some embodiments, the BET of the partially crystallized carbon black is less than 1200 m 2 / g, less than 1000 m 2 / g, less than 800 m 2 / g, less than 700 m 2 / g, less than 600 m 2 / g or less than 500 m 2 / g. In a particular series of embodiments, the BET surface area can be in the range of 40 to 400 m 2 / g, 46 to 350 m 2 / g, 40 to 300 m 2 / g or 40 to 200 m 2 / g. In another embodiment, the BET surface area is less than 425 + / - 25 m 2 / G.

[0026] Another way to characterize the surfaces of carbon blacks is to use the statistical thickness of the surface (STSA according to ASTM D6556). The STSA of many of the carbon blacks described here can be at least 100 m 2 / g, for example in the range of 100 m 2 / g up to 600 m 2 / g. In other cases, the partially crystallized carbon black has an STSA of at least 200 m 2 / g, at least 300 m 2 / g, at least 400 m 2 / g, at least 500 m2 / g or at least 600 m 2 / g. In some embodiments, the STSA of the partially crystallized carbon black is less than 1200 m 2 / g, less than 1000 m 2 / g, less than 800 m 2 / g, less than 700 m 2 / g, less than 600 m 2 / g or less than 500 m 2 / G.

[0027] While heat treatment is a method for providing partial crystallization, the residence time and furnace geometry may need to be adjusted to achieve the desired degree of crystallinity, structure, surface area, and surface energy. For example, it has been found that a carbon black prepared by heating a base carbon black at a temperature of 1100°C to less than 1800°C for a predetermined time (e.g., less than 10 hours, less than 2 hours, or less than 1 hour) can result in a heat-treated carbon black with a BET surface area (ASTM 6556) in the range of 100 m 2 / g up to 1100 m 2 / g and one or more other specific properties, such as a surface energy (SE) of less than 8 mJ / m 2 or less (for example, 6 mJ / m 2 or less or 3 mJ / m 2 or less), a microcrystalline Raman area size (L a) of at least 28 Å and less than 60 Å (for example in the range of 28 Å to 60 Å, at least 28 Å or in the range of 28 Å to 50 Å, etc.) or a combination thereof.

[0028] In many embodiments, the structure of the partially crystallized carbon black can be controlled within a specific range. The structure can be measured using the oil absorption number (OAN), which is known to those skilled in the art and described in ASTM D2414. The OAN is greater than 120 cm 3 / 100g, more than 140 cm 3 / 100g or more than 160 cm 3 / 100g, are less than 200, less than 180 or less than 160 cm 3 / 100g. Experimental data show that if the OAN of the base carbon black is too low, the partial crystallization does not contribute to improvements in thermal conductivity

[0029] In one embodiment of the heat treatment, the base carbon black has a surface energy of more than 10 mJ / m before partial crystallization (base carbon black) 2 and a BET surface area (ASTM 6556) of at least 50 m 2 / g. For example, the BET surface area can be at least 100 m 2 / g, 200 m 2 / g, 300 m 2 / g, at least 500 m 2 / g, at least 1000 m 2 / g, 1200 m 2 / g, at least 1300 m 2 / g, at least 1400 m 2 / g or at least 1500 m 2 / g. In the same or other embodiments, the BET surface area may be less than or equal to 150 m 2 / g, 300 m 2 / g, 500 m 2 / g, 1000 m 2 / g, 1500 m 2 / g or 2100 m 2 / g. The base carbon black can in some cases have a surface energy of more than 10 mJ / m 2 and a BET surface area in the range of 200 m 2 / g up to 1500 m 2 / g, for example a BET surface area in the range of 300 m 2 / g up to 1500 m 2 / g, from 500 m 2 / g up to 1500 m 2 / g, from 1000 m 2 / g up to 1500 m 2 / g, from 300 m 2 / g up to 1000 m 2 / g, from 500 m 2 / g up to 1000 m 2 / g, from 300 m 2 / g up to 500 m 2 / g or from 200 m 2 / g up to 500 m 2 / g. These same BET surface areas can be retained in the partially crystallized carbon blacks prepared from these base carbon blacks, although the surface energy is generally lower than that of the base carbon black. The base carbon black is a furnace black.

[0030] In a specific set of examples, the partially crystallized carbon black has a BET surface area of ​​125-175 m 2 / g, for example in a range of approximately 138 to 169 m 2 / g, for example 130, 135, 138, 142, 147, 150, 155, 160, 165 or 169 m 2 / g; an external surface (STSA) in a range of 135 to 142 m 2 / g, for example 136, 137, 138, 139, 140 or 141 m 2 / g; a total pore volume of 0.44 to 0.49 ml / g, for example 0.45, 0.46, 0.47 or 0.48 ml / g; Raman crystallinity (L a ) from 28.4 to 34.6Å, for example 29.0, 29.5, 30.0, 30.5, 31.0, 31.5, 32.0, 32.5, 33.0, 33.5 or 34.0 Å and a surface energy (SE) of 4.9 to 6.3 mJ / m 2 , for example 5.2, 5.5, 5.8 or 6.1 mJ / m 2 .

[0031] For example, the iodine value according to ASTM D1510 of the partially crystallized carbon black may be less than 450, less than 425, less than 400, less than 350, less than 300, less than 250, or less than 200 mg / g. In the same or other embodiments, the iodine value may be more than 50, more than 100, more than 150, more than 200, more than 250, or more than 300 mg / g.

[0032] The partially crystallized carbon blacks described here are generally unmodified, meaning they have not been subjected to any organic treatment. As used herein, an unmodified carbon black is a carbon black to which no organic groups are chemically attached.

[0033] Carbon black can be provided in any amount suitable for the polymer system employed, the specific end use, the mixing method, the viscosity present, the desired properties of the final product, and other considerations. Partially crystallized carbon black is present in the system at a total concentration within the general range of 12% to 28% by weight, preferably 15% to 25% by weight, for example, 12% to 20%, 15% to 23%, or 17% to 28%. Too high a loading will result in the resulting polymer composition being too viscous to be formed into articles, and too low a loading will not provide sufficient thermal conductivity. It should be understood that the entire amount of carbon black may be added to only one component or may be divided between some or all of the components that make up the polymer system used.Mixtures of 2, 3 or more different partially crystallized carbon blacks can also be used.

[0034] The partially crystallized carbon blacks described here can provide improved thermal conductivity as well as improved rheology compared to the corresponding base carbon black in the same polymer system. For example, the use of the partially crystallized carbon blacks in polymer precursors can enable high loadings without an increase in viscosity, or can enable similar loadings and lower viscosity. When used in polymer systems at concentrations of 12 to 28 wt.%, the partially crystallized carbon blacks can provide a Raman microcrystallinity (L a) of less than 21 Å, improve the thermal conductivity by more than 5, 10, 15 or 20 percent compared to the corresponding base black. At the same concentrations, the thermal conductivity can be improved by more than 1.6 times with respect to the neat polymer, for example from 1.7 times to 3 times or from 2 times to 4 times with respect to the neat polymer. At the same concentrations, the melt flow index (MFI) of the polymer precursor can be improved by more than 50%, 100% or 150%. These improvements in thermal conductivity and viscosity can be utilized individually or in combination. For example, a 1:1 substitution of the partially crystallized carbon black with a base carbon black can provide a polymer composition that has both improved viscosity and improved thermal conductivity.Alternatively, by substituting the partially crystallized carbon black for a base carbon black, the amount of carbon black added to the polymer composition can be increased without loss of flow properties, but with a significant gain in thermal conductivity, due to both more efficient heat transfer per gram of carbon black and the higher loading of carbon black in the composition. In another aspect, the use of a partially crystallized carbon black in a composition allows for the use of a reduced amount of carbon black without loss of thermal conductivity in the polymer composition.

[0035] In some embodiments, the polymer system consists of, or essentially consists of, a polymer and a partially crystallized carbon black. In other embodiments, the polymer component of the composite-polymer composite is more than 50%, more than 75%, or more than 85% of the polymer system by weight. In another embodiment, the polymer system consists of, or essentially consists of, a polymer, a partially crystallized carbon black, and boron nitride (BN).

[0036] Components other than carbon black and the polymer component may be present in the polymer described herein and / or used in its manufacture. The nature, amounts, and / or proportions of these components (also referred to as "additives") typically depend on the polymer system employed, the end use, processing conditions, properties, for example, viscosity of the precursor composition, and other conditions. In many cases, the additives are provided as part of the polymer system employed and / or may be added at a suitable time during the manufacturing process, before or during curing, or at another suitable time. The amounts are often preset by the selected polymer system. This is particularly true for off-the-shelf systems.In other cases, appropriate amounts of additives can be determined based on experience and / or routine testing. Examples of additional ingredients include, but are not limited to, hardeners, rheology modifiers, waxes, reactive diluents, extenders, pigments, fillers, catalysts, OV and heat stabilizers, coupling agents such as silanes, surfactants, tackifiers, solvents, and others, including other additives described elsewhere.

[0037] In some embodiments, the composition may contain a second type of particle to enhance heat transfer. For example, in addition to a partially crystallized carbon black, the composition may also contain a high thermal conductivity (HTC) particle. HTC particles include non-electrically conductive materials, such as ceramics, such as aluminum nitride (AIN), beryllium oxide, silicon carbide, and boron nitride (BN). Electrically conductive HTC particles include metals from the periodic table, such as molybdenum, aluminum, copper, tungsten, silver, and gold. Other HTC particles may include minerals such as diamond, corundum, hematite, spinel, and pyrite. The specific shape of an HTC particle can enhance heat transfer, and the particles may be in the form of spheres, cylinders (rods), cubes, blades, or platelets. HTC particles may also be irregularly shaped.In certain embodiments, these HTC particles include non-carbonaceous particles that have a thermal conductivity greater than 30 W / mK. Specific examples of HTC particles used in conjunction with partially crystallized carbon blacks include BN, MgO, ZnO, and Al. 3 O 2In some cases, the combination of an HTC particle, such as BN, and a partially crystallized carbon black has been shown to enable more efficient heat transfer than the equivalent total (by mass or volume) of BN alone. For example, the combination of an HTC particle, such as BN, and a partially crystallized carbon black can increase the thermal conductivity of a polymer composition by 1.5 times, 2 times, 3 times, 4 times, or multiples, for example, between 1.5 times and 6 times, or from 2 times to 4 times, compared to the same polymer composition containing no BN and partially crystallized carbon black.

[0038] To form the composite polymers and polymer precursors described herein, the components are combined using a suitable mixing process and in a suitable sequence, including the simultaneous mixing of some or all of the starting materials.

[0039] As used herein, a polymer precursor is a monomer or oligomer that is not yet polymerized, but is capable of being converted into a polymer through crosslinking or a polymerization process. The polymer precursors used herein to form carbon black composites are fluid enough that the carbon black can be evenly distributed throughout the precursor. In one example, a partially crystallized carbon black is combined with a polymer precursor, such as a polymer precursor of a thermoset. Under suitable conditions (e.g., specific temperatures, presence of curing agents, and / or parameters), the polymer precursor is cured (polymerization), as is known in the art. The precursor can be an entire system used to form the conductive materials described herein or a component thereof.The partially crystallized carbon black can be dispersed in various forms as an aggregate or in agglomerate form.

[0040] In multi-component systems (i.e., systems consisting of two or more components), the total amount of carbon black may be divided between or among some or all of the components. The proportions in each component may depend, for example, on the relative volumes of the components. In some multi-component systems, attempts are often made to match the viscosity of the components to facilitate processing, such as mixing. Carbon black may be added to two or more precursor components in amounts that result in similar viscosities. These amounts can be determined based on the experience of those skilled in the art or by routine testing.

[0041] The proportions of carbon black in each polymer precursor component may also depend on factors such as the type of cure used, the desired cure time, the properties of the final product, etc., as is known in the art. The weight ratios of carbon black to the polymer precursor may be, for example, from 1:1 to 1:10, for example, from 1:2 to 1:8, or from 1:4 to 1:6. Other suitable ratios may be selected. In an exemplary two-part composition, carbon black is added to both components, with minor amounts (less than 50% by weight, for example, less than 40%, less than 30%, or 25% or less, for example, within the range of about 45% to about 15%; to about 20%, or 35 to about 25% by weight) typically added to the crosslinking agent.

[0042] Various mixing processes are known for mixing solid components with a polymer precursor. For example, dry powder mixing can be used for polymer precursors that are in solid form. Depending on the end use, the resulting mixture can be combined with a liquid to form a slurry or a paste.

[0043] With a precursor having a sufficiently low viscosity, mixing can be conveniently achieved by dispersing carbon black and, optionally, other additives in the precursor. In many cases, carbon black and, optionally, other additives are dispersed using a suitable mixing device, for example, a three-roll mill, sigma paddle mixer, high-shear mixer, or other devices known in the art. The mixing process can be performed manually or by means of a robot.

[0044] Co-solvents and / or dispersants may be added to simplify the process. In one specific embodiment, the dispersion is formed in the absence of additional co-solvents and / or dispersants, i.e., without adding co-solvents and / or dispersants that are not part of the original composition. In other cases, the use of a carbon black as described herein reduces the amounts of solvents and / or dispersants necessary in an original recipe (e.g., a recipe for a composition using untreated carbon black).

[0045] The distribution of carbon black achieved in a mixture can be determined by visual observation or by a suitable quantitative or qualitative analytical method. Uniform or substantially uniform distribution is believed to enhance the electrical conductivity, thermal conductivity, mechanical strength, and / or other properties of the final product.

[0046] In many cases, a composition containing carbon black and a polymer precursor is viscoelastic, meaning it exhibits both viscous and elastic properties upon deformation. While viscous materials resist shear flow and strain linearly with time under stress, elastic materials expand upon strain and quickly return to their original state upon removal of the stress. Viscoelastic materials have elements of both properties and exhibit time-dependent strain.

[0047] Viscoelasticity is typically studied using dynamic mechanical analysis, in which a small oscillating stress is applied and the resulting strain is measured. While in purely elastic materials, stress and strain are in phase, so that the response of one to the other is instantaneous, in purely viscous materials, the strain is delayed by 90 degrees. Viscoelastic materials are thought to exhibit an intermediate behavior, exhibiting some delay in strain.

[0048] The complex dynamic modulus G is usually used to represent the relationship between oscillating stress and strain: G=G'+iG" where: the real part of the complex dynamic modulus, G', is the storage modulus; G" of the imaginary part is the loss modulus; and i2= -1.

[0049] If σ 0 and ε 0are the amplitudes of stress and strain and δ is the phase shift between them, G' = (σ 0 / ε 0 ) cos δ and G'' = (σ 0 / ε 0 ) sin δ.

[0050] Procedures for performing dynamic mechanical analysis (DMA) to determine the elastic modulus (or storage modulus, G'), viscous modulus (or loss modulus, G'') and damping coefficient (tan δ) as a function of temperature, frequency or time are described, for example, in ASTM D4065, D4440 and D5279.

[0051] The combination of carbon black or other solid components with a viscoelastic composition often increases the storage modulus. However, excessive increases can make mixing and / or handling of the composition, including its application, difficult or impossible. In practice, this limits the amount of carbon black that can be added and thus restricts the thermal conductivity and / or other effects primarily intended to be achieved by the addition of carbon black. However, it has been found that a carbon black, such as the partially crystallized carbon blacks described here, can mitigate the increase in storage modulus.For example, a partially crystallized carbon black added to a component of a two-part epoxy system can reduce the storage modulus of the composition by approximately one order of magnitude compared to a control composition identical (same ingredients and amounts) to the composition, except that the carbon black is a base carbon black. The lower viscosity achievable with partially crystallized carbon blacks increases the rheological flexibility of the composition.

[0052] Without being bound to a particular interpretation, it is believed that both particle-polymer compatibility and particle-particle cohesive strength can play a role in the dispersion of the carbon black in a polymer precursor. While the underlying architecture and morphology of a base carbon black particle is essentially unchanged compared to its partially crystallized form, untreated and partially crystallized carbon blacks are believed to behave differently when dispersed. Thus, it is possible that the surface of the partially crystallized carbon particle is more compatible with the polymer (compared to the untreated carbon black), thereby facilitating dispersion. A reduction in particle-particle cohesive strength could also lead to an improvement in dispersion.As a result, a polymer composition containing partially crystallized carbon black can be formulated to a much lower viscosity than one containing untreated carbon black. The manufacturer then has the flexibility to increase the carbon black content and / or the content of other additives. In another approach, mixing, handling, and / or using the lower viscosity composition (at unchanged content) can simplify its use.

[0053] The viscoelastic composition can be applied to a desired application, for example, to a substrate using methods known in the art. The application of the viscoelastic composition can be manual or automated and can be carried out by extrusion, painting, spraying, brushing, dipping, or any other suitable method. In other cases, the composition is molded or extruded.

[0054] To form a thermally conductive polymer, the carbon black-containing composition is cured under suitable conditions (temperature, ramp and soak protocols, time, pressure, radiation, specific curing aids, special atmospheres if necessary, etc.) known in the art or from experience with similar compositions and / or routine testing. For example, in commercial systems, curing is typically performed according to the instructions provided by the manufacturer. As is known in the art, curing conditions are highly dependent on the specific polymer system employed, with heat curing being a common requirement.

[0055] Curing the polymer(s) in the polymer system produces a thermally conductive material that can be considered a polymer-carbon black composite. In many embodiments, the material exhibits good thermal conductivity, as well as good mechanical and rheological properties. ExamplesExample 1 - Viscosity

[0056] To evaluate the rheological effects of using partially crystallized carbon blacks in a polymer precursor, various polymer precursor samples were prepared containing both base carbon blacks and partially crystallized carbon blacks. These included high-density polyethylene (HDPE), polystyrene (PS), polycarbonate (PC), and polyamide-6 (PA). Each of the carbon blacks is listed in Table 1. The carbon blacks were heat-treated in an inert atmosphere at the temperature specified in Table 2 until they reached the Raman area size L specified in Table 2. aThe analyzed properties for each of the carbon blacks are listed in Table 2. The indicator "NA" means that the value was not measured and "ND" means that the value was below the detection limit. The iodine value was determined according to ASTM D1510, the BET surface area was determined according to ASTM D6556, the OAN structure was determined according to ASTM 2414, and the surface energy (SE), Raman crystallinity (L a ) and the percentage crystallinity were determined using the methods described above. The melt index of the polymer composites was measured at the specified loadings and temperatures according to ISO 1133.

[0057] The HDPE resin was Lupolen™ 4261A IM resin from LyondellBasell and had an MFI of 15 g / 10 min at a load of 2.16 kg and a temperature of 190°C. The melt flow index (MFI) for the composite HDPE samples was measured at 21.6 kg and 190°C for 10 minutes. A 1.664 L Banbury internal batch mixer was used to blend the carbon black under the following conditions: Chamber cooling temperature: 40°C Rotor cooling temperature: 40°C Mixing time after flux: 90 s Back pressure: 4.2 bar Rotor speed: 180 rpm

[0058] The polystyrene (PS) resin was Edistir™ N1840 resin from Polimeri. It exhibits an MFI of 10 g / 10 min at a 5 kg load at 200°C. The melt flow index (MFI) of the composite PS samples was measured at 10 kg and 200°C for 10 minutes. A 1.664 l Banbury internal batch mixer was used to mix the carbon black under the following conditions: Chamber cooling temperature: 20°C Rotor cooling temperature: 20°C Mixing time after flux: 90 s Back pressure: 4.2 bar Rotor speed: 180 rpm

[0059] The polycarbonate (PC) resin was Wonderlite™ PC-122 resin from Chimei Asahi. It exhibits an MFI of 22 g / 10 min at a 1.2 kg load at 300°C. The melt flow index of the composite PC samples was measured at 10 kg and 260°C for 10 minutes. The polycarbonate polymers were produced in an APV twin-screw extruder with a moderate shear profile under the following conditions: Screw speed: 300 RPM Throughput: 12 kg / h Temperature from hopper to tool (°C): 175-230-230-260-260-260-260-240

[0060] The polyamide-6 (PA) resin was Zytel™ ST7301NC resin from DuPont. The melt flow index (MFI) for the composite PA samples was measured at 10 kg and 275°C for 10 minutes. The PA polymers were produced in an APV twin-screw extruder with a moderate shear profile under the following conditions: Screw speed 300 RPM Throughput: 12 kg / h Temperature from hopper to tool (°C): 175-230-230-260-260-260-260-240

[0061] The melt flow index results for each of the polymer composites are presented in Table 3 and show that, at the same loading, the composite samples containing the partially crystallized carbon black exhibited significantly higher MFIs than the parent or base carbon black from which they were formed. It should be noted that these improvements were achieved without significant changes to the surface or structure of the carbon blacks. Table 1 - Carbon Black Sample Identification Sample ID Base Carbon Black Treatment CB1 VULCAN XC500 Untreated CB2 VULCAN XC500 Heat treated at 1200°C CB3 VULCAN XC72 Untreated CB4 VULCAN XC72 Heat treated at 1200°C CB5 VULCAN XC200 Untreated CB6 VULCAN XC200 Heat treated at 1400°C CB7 VULCAN XC68 Untreated CB8 VULCAN XC68 Heat treated at 1050°C CB9 SHELF 85 Untreated CB10 SHELF 85 Heat treated at 1200°C CB11 CSX 99 Untreated CB12 CSX 99 Heat treated at 1400°C CB13 VULCAN XC500 Heat treated at 1800°C CB14 VULCAN XC72 Heat treated at 1400 °C CB15 VULCAN XC72 Heat treated at 1500 °C CB16 CSX 691 Untreated Table 2 - Properties of Carbon Black sample I 2 Nr. (mg / g) BET (m 2 / g) OAN (cm) 3 / 100g) SE (mJ / m 2 ) L a (Å) Crystallinity % CB1 73,3 57 148,0 18,0 21 33 CB2 71,1 55 139,5 1,0 38 47 CB3 252,7 235 175,4 14,9 18 29 CB4 177,8 153 164,5 6,3 39,5 47,6 CB5 46 46 115 2,6 18 29 CB6 N / A 46 115 N / A 29 40 CB7 68 58 123 9,3 18,4 29,7 CB8 N / A N / A N / A < 1 29,2 40,2 CB9 16 N / A 36 13,6 17 28 sample I 2 Nr. (mg / g) BET (m 2 / g) OAN (cm) 3 / 100g) SE (mJ / m 2 ) L a (Å) Crystallinity % CB10 16 N / A 36 N / A 32 42 CB11 N / A 425+ / -25 150 16,2 20 31 CB12 N / A 425+ / -25 150 N / A 24 36 CB13 74 N / A 148 ND 95 68 CB14 N / A N / A N / A 1,3 39,5 47,6 CB15 N / A N / A N / A 0,9 41,6 48,9 CB16 15 20 95,2 14 18 29 NA = not available Table 3 - Melt index Loading wt% MFI HDPE MFI PS MFI PC MFI PA CB1 18 8,3 CB2 18 11,9 CB1 24 5,5 11,8 15,9 CB2 24 8,6 13,4 21,6 CB1 26 11,6 CB2 26 19,3 CB3 16 9,3 16,4 CB4 16 10,4 17,5 CB3 22 5,1 7,8 13,4 20,8 CB4 22 7,2 9,2 31,3 23,4 CB3 24 8,9 CB4 24 24,5 CB7 22 5,6 CB8 22 9,2 Example 2 - Thermal conductivity measurements

[0062] To evaluate the thermal conductivity (TC) of the composite polymers with partially crystallized carbon blacks, a series of HDPE composite samples were tested using a NETZSCH ®LFA 467 flashlight at 25°C. The samples included both base carbon blacks and partially crystallized carbon blacks, and the composite polymers were prepared as described above in Example 1. Samples for thermal conductivity measurements were formed into 2.54 cm disks using electrically heated presses. The mold was made from 316 stainless steel plates with four one-inch holes and 316 stainless steel cover plates. One gram of each sample was weighed and filled into each round hole. KEVLAR® Para-Aramid sheets were placed on the top and bottom of each mold. The presses were set to 365°F, and the mold was placed on the presses for 5 minutes, then closed and pressurized to 23 psi for 5 minutes. The pressure was released by opening the presses, removing the hot molds, and placing them on water-cooled presses for 10 minutes.

[0063] The sample size for the measurement was a circular disk with a diameter of 25 mm and a thickness of approximately 1 mm. The sample thickness was measured using a thickness gauge, taking the average of three thickness values. The samples were coated with a thin layer of graphite spray lubricant and dried before measurement. The samples were inserted into the sample holder and equilibrated at 25 °C for 4 minutes. After equilibration, each sample was pulsed with high-intensity, short-duration radiant energy from a Xenophon lamp. The energy of the pulse was absorbed on the front side of the sample, and the temperature rise on the back side of the sample was measured using an IR detector. The thermal diffusivity value was calculated from the measured sample thickness and the time taken to reach a maximum value.The specific heat of each sample was calculated by measuring a standard reference material against a predefined specific heat table (Pyroceram9XX) and using Proteus62 LFA analysis software to calculate the experimental values. Thermal conductivity was calculated using the following equation 1.0: k=ρ*c_p*α where k is the thermal conductivity (W / mK), ρ is the density of the sample (g / m 3 ), cp is the specific heat capacity of the sample (J / g / K) and a is the thermal conductivity of the sample (m 2 / s).

[0064] The thermal conductivity results are shown in Table 4 and in the Fig. 1-5 shown. Fig.Figure 1 shows a bar chart illustrating the relative thermal conductivity of VULCAN XC500 Carbon Black (CB1) and two of its partially crystallized derivatives, CB2 and CB13. The results for CB2 show a significantly higher thermal conductivity compared to the base carbon black. The results for sample CB13, which was heat-treated at a higher temperature than CB2, show a thermal conductivity equivalent to that of the base carbon black CB1. This poor thermal conductivity is believed to be a result of impaired particle dispersion due to over-crystallization of the carbon black, as CB13 has a Raman L a of 95 Å and a percent crystallinity of 68.

[0065] Fig.Figure 2 shows a bar chart showing the relative conductivity of VULCAN XC72 Carbon Black (CB3) and three of its partially crystallized derivatives. Each of the partially crystallized derivatives, CB4, CB14, and CB15, exhibits a significantly higher thermal conductivity compared to the base carbon black, CB3. It should be noted that these three partially crystallized carbon blacks are Raman L a measurements of 39.5, 39.5 and 41.6 Å respectively.

[0066] Fig. Figure 3 shows a bar chart illustrating the relative thermal conductivity of VULCAN XC200 Carbon Black (CB5) and its partially crystallized derivative, CB6. CB6 provides significantly improved thermal conductivity compared to the base carbon black (CB5) and exhibits a Raman L a of 29 Å (an increase of 11 Å).

[0067] Fig.Figure 4 shows a bar chart illustrating the relative thermal conductivity of REGAL 85 Carbon Black (CB9) and its partially crystallized derivative CB10. The partially crystallized derivative exhibits identical thermal conductivity to the base carbon black, CB9. Although partially crystallized, the thermal conductivity is believed to be lower than that of the base carbon black due to its small structure (OAN of 36 cm). 3 / 100g) of both the base carbon black (CB9) and the partially crystallized carbon black (CB10) was not improved.

[0068] Fig.Figure 5 shows a bar graph illustrating the relative thermal conductivity of CSX 99 carbon black (CB11) and its partially crystallized derivative, CB12. The thermal conductivity of the partially crystallized carbon black is slightly lower than that of the base carbon black (CB11) from which it is derived. Although CB12 was partially crystallized, its poor thermal conductivity is believed to be a result of the relatively low Raman L a of 24 Å.

[0069] Overall, these results demonstrate that the thermal conductivity of polymer composites can be significantly improved by substituting a carbon black with a partially crystallized carbon black. These data also demonstrate that optimal thermal conductivity results are achieved when Raman L a more than 24 Å and less than 95 Å and if the OAN structure of the partially crystallized carbon black is more than 36 cm 3 / 100g.

[0070] As mentioned above, the partially crystallized carbon blacks are also capable of higher loadings than the base carbon blacks without affecting the rheology of the polymer precursor. These higher loadings can be combined with the higher thermal conductivity to provide polymer composites with significantly higher thermal conductivity without loss of rheological properties. Alternatively, lower carbon black loadings (than those of the base carbon blacks) can be used without any loss of thermal conductivity of the polymer composite. Table 4 - Thermal conductivity of HDPE composites. Sample ID Concentration in HDPE (wt%) Thermal conductivity (W / mK) CB1 18,8 0,45 CB2 18,6 0,51 CB3 20,2 0,38 CB4 16,7 0,48 CB5 21 0,37 CB6 21 0,44 CB9 21,1 0,39 CB10 21,1 0,39 CB11 19,9 0,35 CB12 19,8 0,34 CB13 19,9 0,45 CB14 14,6 0,48 CB15 15,4 0,51 Example 3 - Thermal conductivity measurements

[0071] In another series of experiments, the thermal conductivity of composite samples prepared using two different fillers was measured. The results are shown in Table 5 below. The filler concentrations are given in volume percent (vol%). All samples were compounded with the same polyolefin resin, Lupolen 4261 A IM HDPE, available from Lyondell Basell Industries. This polyolefin has a melt index of 15g / 10min (@190°C and 21.6Kg). Sample "BN1" is grade PCTP30D high thermal conductivity (HTC) particles available from Saint-Gobain. These BN particles are platelets with a D 50 of 180 µm, were not heat-treated, and exhibit a thermal conductivity (W / mK) of 30-130, a refractive index of 1.74, and a dielectric constant of 3 to 4. Each composite was compounded as described below. Experimental molding process

[0072] Each composite was compounded by mixing the particles and polymer resin using a 60cc Brabender mixer (0.7 filler density) at 170°C for 15 minutes at 35 rpm. Each batch was then removed from the mixing chamber and cooled to room temperature. Once the mixture reached room temperature, it was fed into a Retsch SM300 mill operating at 800 rpm to grind the polymer composite into a powder. The resulting polymer composite powder was collected and molded using a heated press at 185°C (365°F) for 5 minutes. To facilitate the removal step, Kevlar sheets were placed between the stainless steel mold and the powder composite. The resulting polymer composite molds were then placed on water-cooled presses for 10 minutes. The final result was a set of 25 mm (diameter) and 1 mm (thickness) discs suitable for thermal conductivity measurements. Experimental procedure for thermal conductivity

[0073] The thermal conductivity of all samples was measured using a NETZSCH LFA467 thermal conductivity meter at 25°C. The sample size for the measurement was a circular disk with a diameter of 25 mm and a thickness of approximately 1 mm. The sample thickness was measured using a thickness gauge, taking the average of three thickness values. The samples were coated with a thin layer of graphite spray lubricant and dried before measurement. The samples were inserted into the sample holder and equilibrated at 25°C for 4 minutes. After equilibration, each sample was pulsed with high-intensity, short-wave radiant energy from a Xenophon lamp. The energy of the pulse was absorbed on the front side of the sample, and the temperature rise on the back side of the sample was measured using an IR detector. The thermal diffusivity value was calculated from the measured sample thickness and the time taken to reach a maximum value.The specific heat of each sample was calculated by measuring a standard reference material against a predefined specific heat table (Pyroceram9XX) and using Proteus62 LFA analysis software to calculate the experimental values. Thermal conductivity was calculated using the following equation: k=ρ*c_p*α where k is the thermal conductivity (W / mK), p is the density of the sample (g / m 3 ), cp is the specific heat capacity of the sample (J / g / K) and a is the thermal diffusivity of the sample (m 2 / s). The results are shown in Table 5 below Table 5 Quality Volume-% average TC [W / mK] Mean standard deviation [W / mK] CB1 10 0,363 0,006 CB1 15 0,385 0,007 CB1 20 0,412 0,011 CB1 30 0,498 0,014 CB1 + BN1 20 BN1 0,580 0,066 2.5 CB1 CB1 + BN1 20 BN1 0,615 0,061 5 CB1 CB1 + BN1 20 BN1 0,708 0,023 10 CB1 CB16 + BN1 20 BN1 0,546 0,020 2.5 CB2 CB16 + BN1 20 BN1 0,559 0,032 5 CB2 CB16 + BN1 20 BN1 0,673 0,054 10 CB2 BN1 10 0,469 0,025 BN1 15 0,626 0,091 BN1 20 1,123 0,186 BN1 27 1,404 0,043 CB2 + BN1 20 BN1 1,208 0,073 2.5 CB2 CB2 + BN1 20 BN1 1,367 0,078 5CB2 CB2 + BN1 20 BN1 1,599 0,092 10 CB2 CB2 10 0,452 0,072 CB2 15 0,481 0,102 CB2 20 0,536 0,038 CB2 25 0,590 0,049 HDPE None 0,289 0,020

[0074] Fig.Figure 6 shows a graphical representation of the thermal conductivity of composites containing either BN alone, thermally treated carbon black alone, or untreated carbon black alone. The results demonstrate the excellent heat transfer properties of BN, but also show that the crystallized carbon black (CB2) is significantly better than its parent material, CB1.

[0075] Fig.Figure 7 adds some of the composites containing two different particle types. The combination of CB1 and BN1, as well as the combination of CB16 and BN1, are plotted. From this plot, it is clear that the combination of these carbon blacks and boron nitride actually reduces the thermal conductivity compared to BN alone. Each of the particle ratios tested (20 + 2.5, 20 + 5, and 20 + 10) resulted in a lower thermal conductivity than just 20 vol% BN. This means that these carbon blacks, compared to boron nitride, reduce the thermal conductivity of the composite compared to the composite containing only boron nitride and no carbon blacks.

[0076] Fig.8 adds the polymer composite containing a mixture of BN and partially crystallized carbon black. In this case, the addition of Carbon Black CB2 improves the thermal conductivity over BN alone. The BN1-CB2 combination provides better thermal conductivity in the polymer composite than that expected from summing the thermal conductivity contributions provided by each constituent particle alone. The BN1-CB2 combination contributes a greater amount to the thermal conductivity than an equivalent amount of pure BN. For example, at a total particle volume of more than 25%, the trend lines show that the BN1-CB2 combination provides better thermal conductivity than an equivalent amount of BN1 alone. By replacing some of the BN in a composite with a partially crystallized carbon black, costs can be reduced while actually increasing thermal conductivity.This is shown for ratios (by volume) of BN to CB of 2:1, 4:1 and 8:1 at total particle loadings of 30 vol%, 25 vol% and 22.5 vol%, respectively. Example 4

[0077] Composites were prepared according to the compositions given in Table 6 below, using Zytel ST7301NC polyamide 6 from DuPont as the polymer. BN2 is 15 / 400 platelet boron nitride available from 3M. The composites were blended in a Baker Perkins APV twin-screw extruder with a screw diameter of 27 mm and a length / diameter ratio of 40.5 and cooled with a water bath. A #2 screw was used, and the extruder operated at 300 rpm, with a throughput of 8 kg / hour for two strands. Zones 2, 3, and 9 were maintained at 250 °C, zone 4 at 260 °C, and zones 5-8 at 270 °C. The melt tooling was in the range of 260 and 272 °C. Vent port 1 was open to atmosphere, vent port 2 was closed, and vent port 3 was kept under vacuum. The torque ranged between 33 and 40%, with the exception of the 30 vol. sample.-% BN1, at which the torque was not stable. The thermal conductivity and volume resistivity were measured as described in Example 3 and are also listed in Table 6 below. The melt flow index (MFI) was measured according to ASTM D1238 (275 °C / 5 kg for all samples except the pure polymer, which was 275 °C / 2.16 kg). Table 6 Quality Volume-% Average TC [W / mK] Mean standard deviation [W / mK] MFI CB1 + BN1 CB1 5; BN1 20 0,611 0,042 11,5 CB1 + BN1 CB1 10; BN1 20 0,649 0,049 0,8 BN1 20 0,511 0,030 36,8 BN1 30 0,785 0,027 6,0 BN1 35 0,892 0,017 2,1 CB2 + BN1 CB2 5; BN1 20 0,636 0,030 13,3 CB2 + BN1 CB2 10; BN1 20 0,761 0,016 0,8 CB2 + BN2 CB2 10; BN2 20 0,845 0,020 1,0 No CB 0,301 0,029 26,9 CB2 25 0,705 0,032 - - - CB2 30 0,814 0,027 0 CB1 30 0,581 0,015 0

[0078] Additionally, composites were prepared using the HDPE of Example 3 but using the blending procedures of Example 4, using 20 vol% BN1 and 5 vol% CB2 to achieve a thermal conductivity of 1.116 + / - 0.030 W / mK. This is less than the thermal conductivity of the same composite obtained using the procedure of Example 3. Without wishing to be bound by any particular theory, it is believed that the higher shear exerted by the twin-screw extruder in Example 4 may have fractured some of the boron nitride platelets, thereby reducing the thermal conductivity compared to the composite obtained using the lower shear of the barbender mixer in Example 3.

[0079] All definitions as defined and used herein shall be construed as giving preference to dictionary definitions, definitions in referenced documents, and / or the ordinary meanings of the defined terms.

[0080] The indefinite articles “a” and “an” as used in the specification and claims shall be construed to mean “at least one” unless expressly stated otherwise.

[0081] The term "and / or" used herein in the description and claims should be understood to mean "either one or both" of the elements so related, meaning that the elements are present together in some cases and separately in others. Elements other than those specifically recited herein by the "and / or" clause may be present, whether related or unrelated to the specifically recited elements, unless expressly stated otherwise.

[0082] All references, patents and patent applications and publications cited or referred to in this application are incorporated herein by reference in their entirety.

Claims

[1] Composite polymer composition comprising: a polymer matrix; and a partially crystallized carbon black dispersed in the polymer matrix in a concentration of 12 to 28 wt.%, wherein the carbon black has an OAN structure of more than 120 cm 3 / 100g and less than 200 cm 3 / 100g, a surface energy of less than 8 mJ / m 2 , a percentage crystallinity of less than 65% and a microcrystalline Raman area size (L a ) of more than or equal to 28 Å, wherein the carbon black is produced by thermal treatment of a furnace black at a temperature of more than 700°C and less than 1800°C. [2] The composite polymer composition according to claim 1, wherein the composite polymer composition is a plastic composition. [3] A composite polymer composition according to any one of the preceding claims, wherein the polymer matrix comprises a copolymer or terpolymer. [4] Composite polymer composition according to one of the preceding claims, wherein the polymer matrix comprises a polyolefin, a polystyrene (PS), a polycarbonate (PC), a polyamide (PA) and / or a polyamine. [5] A composite polymer composition according to any one of the preceding claims, wherein the partially crystallized carbon black has a microcrystalline Raman area (L a ) of more than or equal to 35 Å and a surface energy of more than 1 mJ / m 2 has. [6] Composite polymer composition according to any one of the preceding claims, wherein the polymer matrix is ​​selected from thermoplastic polyolefins (TPO), polyethylene (PE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), ultra-high-molecular-weight polyethylene (UHMWPE), very-low-density polyethylene (VLDPE), metallocene medium-density polyethylene (mLLDPE), polypropylene, polypropylene copolymers, ethylene-propylene rubber (EPR), ethylene-propylene-diene terpolymers (EPDM), acrylonitrile-butadiene-styrene (ABS), acrylonitrile-EPDM-styrene (AES), styrene-butadiene-styrene (SBS), polyoxymethylene (POM), polyvinyl chloride (PVC), tetraethylene-hexapropylene-vinylidene fluoride polymers (THV), perfluoroalkoxy polymers (PFA), polyhexafluoropropylene (HFP), polyketones (PK), ethylene-vinyl alcohol (EVOH), copolyesters, polyurethanes (PU), thermoplastic polyurethanes, polybutylene terephthalate (PBT),Polyethylene terephthalate (PET), polyphenylene oxide (PPO), polyphenylene ether (PPE), an acrylic, an epoxy, a silicone, a phenolic resin, a polyimide, a plastisol and polyvinyl acetate. [7] A composite polymer composition according to any one of the preceding claims, further comprising a non-carbonaceous particle having a thermal conductivity of more than 30 W / mK. [8] The composite polymer composition according to claim 7, wherein the non-carbonaceous particle is selected from BN, MgO, ZnO and Al2O3. [9] The composite polymer composition according to claim 8, wherein the non-carbonaceous particle comprises BN and the volume ratio of the partially crystallized carbon black to BN is in the range of 1:1 to 1:

10. [10] Composite polymer composition according to any one of claims 1-9, wherein the thermal conductivity of the composite polymer composition is at least 1.6 times greater than the thermal conductivity of the polymer matrix. [11] Composite polymer composition according to any one of claims 1-10, wherein the thermal conductivity of the composite polymer composition is at least 1.7 times greater than the thermal conductivity of the polymer matrix. [12] Composite polymer composition according to any one of claims 1-11, wherein the thermal conductivity of the composite polymer composition is 2-4 times greater than the thermal conductivity of the polymer matrix. [13] The composite polymer composition according to any one of claims 1-12, wherein the partially crystallized carbon black improves a thermal conductivity of the composite polymer composition by at least 10% with respect to an untreated carbon black. [14] The composite polymer composition according to any one of claims 1-13, wherein the percent crystallinity of carbon black is greater than or equal to 35%. [15] Composite polymer composition according to any one of claims 1-13, wherein the carbon black has a BET surface area of ​​less than 425 m 2 / g. [16] A composite polymer composition according to any one of claims 1-13, wherein the carbon black has an iodine value of less than 425 mg / g. [17] The composite polymer composition of any one of claims 1-13, further comprising a second carbon black. [18] A composite polymer composition according to any one of claims 1-13, wherein the partially crystallized carbon black is prepared by measuring the microcrystalline Raman area (L a ) of a base carbon black by more than 5 Å. [19] Masterbatch comprising the composite polymer composition according to any one of claims 1-13. [20] Polymer precursor composition comprising: a polymer precursor comprising a polymerizable monomer or oligomer; and a partially crystallized carbon black dispersed in the monomer or oligomer in a concentration of 12 to 28 wt.%, wherein the carbon black has an OAN structure of more than 120 cm 3 / 100g and less than 200 cm 3 / 100g, a surface energy of less than 8 mJ / m 2 , a percent crystallinity of less than 65% and a microcrystalline Raman area size (La) of greater than or equal to 28 Å; wherein the carbon black is produced by thermal treatment of a furnace black at a temperature of more than 700°C and less than 1800°C. [21] Polymer precursor composition according to claim 20, wherein the polymer precursor is a precursor of a polymer selected from thermoplastic polyolefins (TPO), polyethylene (PE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ultra-high molecular weight polyethylene (UHMWPE), very low density polyethylene (VLDPE), metallocene medium density polyethylene (mLLDPE), polypropylene, polypropylene copolymers, ethylene-propylene rubber (EPR), ethylene-propylene-diene terpolymers (EPDM), acrylonitrile-butadiene-styrene (ABS), acrylonitrile-EPDM-styrene (AES), styrene-butadiene-styrene (SBS), polyoxymethylene (POM), polyvinyl chloride (PVC), tetraethylene-hexapropylene-vinylidene fluoride polymers (THV), Perfluoroalkoxy polymers (PFA), polyhexafluoropropylene (HFP), polyketones (PK), ethylene-vinyl alcohol (EVOH), copolyesters, polyurethanes (PU), thermoplastic polyurethanes, polybutylene terephthalate (PBT),Polyethylene terephthalate (PET), polyphenylene oxide (PPO), polyphenylene ether (PPE), an acrylic, an epoxy, a silicone, a phenolic resin, a polyimide, a plastisol and polyvinyl acetate. [22] The polymer precursor composition of claim 20, wherein the precursor comprises a precursor of a polyolefin, a polystyrene (PS), a polycarbonate (PC), a polyamide (PA) and / or a polyamine. [23] A polymer precursor composition according to any one of claims 20-22, further comprising a non-carbonaceous particle having a thermal conductivity of more than 30 W / mK. [24] The polymer precursor composition of claim 23, wherein the non-carbonaceous particle is selected from BN, MgO, ZnO and Al2O3. [25] The polymer precursor composition of claim 24, wherein the non-carbonaceous particle comprises BN and the volume ratio of the partially crystallized carbon black to BN is in the range of 1:1 to 1:

10. [26] Polymer precursor composition according to any one of claims 20-25, wherein after polymerization a thermal conductivity of the polymerized polymer precursor composition is at least 1.6 times greater than the thermal conductivity of a polymer of the polymer precursor. [27] Polymer precursor composition according to any one of claims 20-25, wherein after polymerization a thermal conductivity of the polymerized polymer precursor composition is at least 1.7 times greater than the thermal conductivity of a polymer of the polymer precursor. [28] Polymer precursor composition according to any one of claims 20-25, wherein after polymerization, a thermal conductivity of the polymerized polymer precursor composition is 2-4 times greater than the thermal conductivity of a polymer of the polymer precursor. [29] The polymer precursor composition according to any one of claims 20-25, wherein the partially crystallized carbon black improves a thermal conductivity of a polymer of the polymer precursor composition by at least 10% relative to an untreated carbon black. [30] The polymer precursor composition of any one of claims 20-25, wherein the percent crystallinity of carbon black is greater than or equal to 35%. [31] A polymer precursor composition according to any one of claims 20-25, wherein the carbon black has a BET surface area of ​​less than 425 m 2 / g. [32] A polymer precursor composition according to any one of claims 20-25, wherein the carbon black has an iodine value of less than 425 mg / g. [33] The polymer precursor composition of any one of claims 20-25, further comprising a second carbon black. [34] A polymer precursor composition according to any one of claims 20-25, wherein the partially crystallized carbon black is prepared by measuring the microcrystalline Raman area (L a ) of a base carbon black by more than 5 Å. [35] A product comprising the composite polymer composition of any one of claims 1-13, wherein the product is selected from wire and cable sheathing, 3D printed products, automotive parts, and LED housings and devices.

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