Spherical hybrid filler BN@Al2O3 via chemical adhesive for enhancing thermal conductivity and processability of silicon rubber

Hexagonal boron nitride (h-BN) is an ideal candidate material for electrical and electronic systems due to its excellent performance. However, the addition of platelet-like h-BN leads to a dramatic increase of viscosity of composites and anisotropic thermal conductivity of composites. Herein, modified h-BN (m-BN) was coated onto spherical α-Al₂O₃ via chemical adhesive, and core-shell structured hybrid spherical filler (m-BN@Al₂O₃) was prepared. Furthermore, the microstructure, rheology, mechanical properties, and thermal conductivity of hybrid filler/polydimethylsiloxane (PDMS) were studied. At 60 vol% filler loading, the thermal conductivity of m-BN@Al₂O₃/PDMS is up to 2.23 W·m⁻¹·K⁻¹, which is 86% higher than that of Al₂O₃/PDMS and the ratio of in-plane diffusivity to through-plane diffusivity decreases from 2.0 to 1.0. At meanwhile, the viscosity of m-BN@Al₂O₃/PDMS is about one fourth of the viscosity of m-BN/Al₂O₃/PDMS. This simple and versatile strategy opens a pavement for enhancing the thermal conductivity of polymer and has great potential in high-frequency communication.     

Preparation of a novel bi-layer modified alumina-based hybrid material and its effect on the thermal conductivity enhancement of polymer composites

In this work, a new kind of double layers modified alumina-based hybrid (silver@copper@alumina (Ag@Cu@Al₂O₃) hybrid) was successfully synthesized through the two-step layer-by-layer process. First, copper (Cu) nanoparticles were assembled onto alumina (Al₂O₃) particles by reduction of Cu²⁺. Second, Ag@Cu@Al₂O₃ hybrids were assembled via Ag deposition on the surface of Cu@Al₂O₃ particles. The obtained Ag@Cu@Al₂O₃ hybrids served as thermally conductive fillers to greatly boost the thermal conductivity of poly (dimethylsiloxane) (PDMS). The thermal conductivity reached 1.465 W m^?1 K^?1 at 85 wt% filler loading. The thermal conductivity of PDMS matrix was increased more than 7 times by the addition of Ag@Cu@Al₂O₃ hybrid, which was much higher than single layer modified alumina-based hybrids (Ag@Al₂O₃ and Cu@Al₂O₃ hybrids) and virgin Al₂O₃ particle. The effect of double layers modified filler, single layer modified filler and virgin filler on the thermal conductivity of PDMS matrix was discussed in detail and the mechanism of these fillers for improving thermal conductivity was studied through Foygel's thermal conduction model. Otherwise, electric, mechanical and thermal properties of Ag@Cu@Al₂O₃/PDMS composites were also further tested and analyzed.     

Polymer composites with enhanced thermal conductivity via oriented boron nitride and alumina hybrid fillers assisted by 3-D printing

Herein, oriented boron nitride (BN)/alumina (Al₂O₃)/polydimethylsiloxane (PDMS) composites were obtained by filler orientation due to the shear-inducing effect via 3-D printing. The oriented BN platelets acted as a rapid highway for heat transfer in the matrix and resulted in a significant increase in the thermal conductivity along the orientation direction. Extra addition of spherical Al₂O₃ enhanced the fillers networks and resulted in the dramatic growth of slurry viscosity. This, together with filler orientation induced the synergism and provided large increases in the thermal conductivity. A high orientation degree of 90.65% and in-plane thermal conductivity of 3.64 W/(m∙K) were realized in the composites with oriented 35 wt% BN and 30 wt% Al₂O₃ hybrid fillers. We attributed the influence of filler orientation and hybrid fillers on the thermal conductivity to the decrease of thermal interface resistance of composites and proposed possible theoretical models for the thermal conductivity enhancement mechanisms.     

Preparation of nano‐reinforced thermal conductive natural rubber composites

Natural rubber (NR) composites highly filled with nano‐α‐alumina (nano‐α‐Al₂O₃) modified in situ by the silane coupling agent bis‐(3‐triethoxysilylpropyl)‐tetrasulfide (Si69) were prepared. The effects of various modification conditions and filler loading on the properties of the nano‐α‐Al₂O₃/NR composites were investigated. The results indicated that the preparation conditions for optimum mechanical (both static and dynamic) properties and thermal conductivity were as follows: 100 phr of nano‐α‐Al₂O₃, 6 phr of Si69, heat‐treatment time of 5 min at 150°C. Furthermore, two other types of fillers were also investigated as thermally conductive reinforcing fillers for the NR systems: (1) hybrid fillers composed of 100 phr of nano‐α‐Al₂O₃ and various amounts of the carbon black (CB) N330 and (2) nano‐γ‐Al₂O₃, the particles of which are smaller than those of nano‐α‐Al₂O₃. The hybrid fillers had better mechanical properties and dynamic performance with higher thermal conductivity, which means that it can be expected to endow the rubber products serving under dynamic conditions with much longer service life. The smaller sized nano‐γ‐Al₂O₃ particles performed better than the larger‐sized nano‐α‐Al₂O₃ particles in reinforcing NR. However, the composites filled with nano‐γ‐Al₂O₃ had lower thermal conductivity than those filled with nano‐α‐Al₂O₃ and badly deteriorated dynamic properties at loadings higher than 50 phr, both indicating that nano‐γ‐Al₂O₃ is not a good candidate for novel thermally conductive reinforcing filler. POLYM. COMPOS., 37:771–781, 2016. © 2014 Society of Plastics Engineers     

Biphenyl liquid crystal epoxy containing flexible chain: Synthesis and thermal properties

A biphenyl type liquid crystal epoxy (LCE) monomer 4,4′-di(2,3-epoxyhexyloxy)biphenyl (LCBP4) containing flexible chain was synthesized and the curing behavior was investigated using 4,4′-diaminodiphenylmethane (DDM) as the curing agent. The effect of curing condition on the formation of the liquid crystalline phase was examined. The cured samples show good mechanical properties and thermal stabilities. Moreover, the relationship between thermal conductivity and structure of liquid crystalline domain was also discussed. The samples show high thermal conductivity up to 0.28–0.31 W/(m*K), which is 1.5 times as high as that of conventional epoxy systems. In addition, thermal conductive filler, Al₂O₃, was introduced into LCBP4/DDM to obtain higher thermal conductive composites. When the content of Al₂O₃ was 80 wt%, the thermal conductivity of the composite reached to 1.86 W/(m*K), while that of diglycidyl ether of bisphenol A (Bis-A) epoxy resin/DDM/Al₂O₃ was 1.15 W/(m*K). Compared with Bis-A epoxy resin, the formation of liquid crystal domains in the cured LCE resin enhanced the thermal conductivity synergistically with the presence of Al₂O₃. Furthermore, the introduction of Al₂O₃ also slightly increased the thermal stabilities of the cured LCE.     

Effect of different size complex fillers on thermal conductivity of PA6 thermal composites

ABSTRACT

Nylon 6 (PA6) thermal conductive composites were prepared by melt blending with different sizes of spherical Al₂O₃ and AlN and the filling amount was 60 wt%. This paper explored the effects of different particle sizes and filler kinds on the thermal conductivity and mechanical properties of the composites. The results showed that the composites filled with AlN and spherical Al₂O₃ had higher thermal conductivity than the composites filled with single filler under the same filling amount. When the mass ratio of 48 μm spherical Al₂O₃ and 14 μm AlN was 1:2, the thermal conductivity and thermal diffusivity was 2.44 W/(m·K) and 0.72 mm²/s, respectively. In addition,the tensile strength was 57.50 MPa and the impact strength was 6.13 KJ/m². By comparing actual thermal conductivity value with the theoretical value calculated by Agari model, we found that actual value of alumina filling was close to the theoretical value.     

Effect of nanoparticles on the performance of thermally conductive epoxy adhesives

Microsized or nanosized α‐alumina (Al₂O₃) and boron nitride (BN) were effectively treated by silanes or diisocyanate, and then filled into the epoxy to prepare thermally conductive adhesives. The effects of surface modification and particle size on the performance of thermally conductive epoxy adhesives were investigated. It was revealed that epoxy adhesives filled with nanosized particles performed higher thermal conductivity, electrical insulation, and mechanical strength than those filled with microsized ones. It was also indicated that surface modification of the particles was beneficial for improving thermal conductivity of the epoxy composites, which was due to the decrease of thermal contact resistance of the filler‐matrix through the improvement of the interface between filler and matrix by surface treatment. A synergic effect was found when epoxy adhesives were filled with combination of Al₂O₃ nanoparticles and microsized BN platelets, that is, the thermal conductivity was higher than that of any sole particles filled epoxy composites at a constant loading content. The heat conductive mechanism was proposed that conductive networks easily formed among nano‐Al₂O₃ particles and micro‐BN platelets and the thermal resistance decreased due to the contact between the nano‐Al₂O₃ and BN, which resulted in improving the thermal conductivity. POLYM. ENG. SCI., 50:1809–1819, 2010. © 2010 Society of Plastics Engineers     

Properties of thermally conductive silicone rubbers filled with admicellar polymerized polypyrrole-coated Al2O3 particles

Polypyrrole (PPy) nanolayers were introduced on the surface of alumina (Al₂O₃) particles via admicellar polymerization. The properties of silicone rubbers (SRs) filled with PPy-coated Al₂O₃ and pristine Al₂O₃ as thermally conductive fillers were studied and compared. The results demonstrate that the addition of PPy-coated Al₂O₃ leads to a better interfacial compatibility but lower cross-linking density of the composites than pristine Al₂O₃. The improvement in the compatibility and the decrease in the cross-linking density are paradoxes in affecting mechanical properties. The improvement in the compatibility shows a slight predominance on the strength at low-filler contents. Lower cross-linking density of modified-Al₂O₃/SR composites led to a better processing performance and a higher maximum filler loading amount than the pristine Al₂O₃/SR composites, which is beneficial to increasing the thermal conductivity and maintaining a relatively good strength. The PPy-coated Al₂O₃/SR composite with 83 wt% filler content has a thermal conductivity of 1.98 W/(m K) and a tensile strength of 2.9 MPa, and the elongation at break was 63%. Functionalized fillers by admicellar polymerization used in the fabrication of filler/SR composites not only improve the interfacial compatibility but also optimize and expand the functions of the composites, which has great significance for the production and application of thermally conductive SR in some branches of industry (automotive, electrical engineering, etc.) in the future.     

Novel heat‐conductive composite silicone rubber

The silicone rubber with good thermal conductivity and electrical insulation was obtained by taking vinyl endblocked polymethylsiloxane as basic gum and thermally conductive, but electrically insulating hybrid Al₂O₃ powder as fillers. The effects of the amount of Al₂O₃ on the thermal conductivity, coefficient of thermal expansion (CTE), heat stability, and mechanical properties of the silicone rubber were investigated, and it was found that the thermal conductivity and heat stability increased, but the CTE decreased with increasing Al₂O₃ fillers content. The silicone rubber filled with hybrid Al₂O₃ fillers exhibited higher thermal conductivity compared with that filled with single particle size. Furthermore, a new type of thermally conductive silicone rubber composites, possessing thermal conductivity of 0.92 W/mK, good electrical insulation, and mechanical properties, was developed using electrical glass cloth as reinforcement. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2478–2483, 2007     

Electrical and thermal studies of the distribution of carbon black in a polyester matrix in the presence of aluminum oxide

The distribution of a filler in a polymeric matrix is one of the most important factors affecting the physical properties of the final product. For this reason, the main objective of this study was to introduce aluminum oxide (Al₂O₃), acting as a dispersing agent, to reduce the filler–filler interaction and enhance the filler–polymer interaction. To achieve this aim, the electrical behavior of a styrenated polyester resin filled with different amounts of high‐abrasion furnace black in the presence of 5% Al₂O₃ was studied in the vicinity of the percolation threshold to evaluate the effect of the addition of Al₂O₃ in an attempt to reduce the filler–filler interaction through the polyester matrix. At a certain concentration of carbon black, an abrupt increase was noticed through electrical conductivity, permittivity, and dielectric loss investigations. With this increase, the tendency of conductive chain formation increased through the aggregation of a carbon black particle network. The addition of 5% Al₂O₃ improved the filler distribution by lowering the aggregate size and consequently enhanced the formation of the network. From the Arrhenius temperature dependence of the electrical conductivity, the activation energy and pre‐exponential factor were obtained, and they confirmed the validity of the compensation law for the semiconducting composite systems. The composites were also analyzed by thermogravimetric analysis. Al₂O₃ improved the thermal stability of the composites in comparison with that of a sample free of Al₂O₃. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

A Concurrent Enhancement of Both In-Plane and Through-Plane Thermal Conductivity of Injection Molded Polycarbonate/Boron Nitride/Alumina Composites by Constructing a Dense Filler Packing Structure

In this work, a facile strategy is proposed to concurrently enhance both in-plane and through-plane thermal conductivity of injection molded polycarbonate (PC)-based composites by constructing a dense filler packing structure with planar boron nitride (BN) and spherical alumina (Al₂O₃) particles. The state of orientation of BN platelets is altered with the presence of Al₂O₃, which is favorable for improving both in-plane and through-plane thermal conductivity of subsequent moldings. Rheological analysis showed that the formation of intact thermal conductive pathways is crucial to the overall enhancement of thermal conductivity. Both in-plane and through-plane thermal conductivity of PC/BN(20 wt%)/Al₂O₃(40 wt%) composites reached as high as 1.52 and 1.09 W mK⁻¹, which are 485% and 474% higher than that of pure PC counterparts, respectively. Furthermore, the prepared samples demonstrated excellent electrical insulation and dielectric properties which show potential application in electronic and automotive industries.     

Magnetically aligning multilayer graphene to enhance thermal conductivity of silicone rubber composites

The increasing demand for packaging materials calls for new technologies to achieve excellent thermal conductivity of polymer composites with low content of thermal conductive filler. This article prepared a kind of magnetically functionalized multilayer graphene (Fe₃O₄@MG) via electrostatic interactions, which efficiently enhanced the thermal conductivity of silicone rubber (SR) composites by the alignment of Fe₃O₄@MG in an external magnetic field. The morphology and structure of the Fe₃O₄@MG together with the thermal conductivity of corresponding Fe₃O₄@MG/SR composites were systematically investigated by SEM, TEM, XRD, elemental mapping, and thermal conductivity tester. The obtained results showed that Fe₃O₄@MG was induced to form chain-like bundles in silicone rubber matrix under the applied magnetic field, which enhanced the MG–MG interaction, and formed effective thermal pathways in the alignment direction. Furthermore, as coating mass ratio of Fe₃O₄@MG increased, the thermal conductivity of randomly oriented Fe₃O₄@MG/silicone rubber composites (R-Fe₃O₄@MG/SR) decreased gradually, whereas the through-plane thermal conductivity of vertically aligned Fe₃O₄@MG/silicone rubber composites (V-Fe₃O₄@MG/SR) increased even filled with same contents of thermal conductive filler. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47951.     

Synergistic thermal conductivity enhancement of PC/ABS composites containing alumina/magnesia/graphene nanoplatelets

Graphene nanoplatelets (GNPs) have attracted considerable attention in the field of thermal management materials due to their unique structure and exceptional thermal conductive properties. In this work, we demonstrate a significant synergistic effect of GNPs, alumina (Al₂O₃), and magnesia (MgO) in improving the thermal conductivity of polycarbonate/acrylonitrile‐butadiene‐styrene polymer alloy (PC/ABS) composites. The thermal conductivity of the composites prepared through partial replacement of Al₂O₃ and MgO with GNPs could increase dramatically compared with that without GNPs. The maximum thermal conductivity of the composite is 3.11 W mK⁻¹ at total mass fraction of 70% with 0.5 wt% GNPs loading. It increases 60% compared with that without GNPs (1.95 W mK⁻¹). The synergistic effect results from the compact packing structure formed by Al₂O₃/MgO and the bridging of GNPs with Al₂O₃/MgO, thus promoting the formation of effective thermal conduction pathways within PC/ABS matrix. More importantly, together with the intrinsically high thermal conductivity of GNPs, boosted and effective pathways for phonon transport can be created, thus decrease the thermal resistance at the interface between fillers and PC/ABS matrix and increase the thermal conductivity of composites. POLYM. COMPOS., 38:2221–2227, 2017. © 2015 Society of Plastics Engineers     

Effective thermal conductivity and thermal properties of phthalonitrile‐terminated poly(arylene ether nitriles) composites with hybrid functionalized alumina

A polymer‐based thermal conductive composite has been developed. It is based on a dispersion of micro‐ and nanosized alumina (Al₂O₃) in the phthalonitrile‐terminated poly (arylene ether nitriles) (PEN‐t‐ph) via solution casting method. The Al₂O₃ with different particle sizes were functionalized with phthalocyanine (Pc) which was used as coupling agent to improve the compatibility of Al₂O₃ and PEN‐t‐ph matrix. The content of microsized functionalized Al₂O₃ (m‐f‐Al₂O₃) maintained at 30 wt % to form the main thermally conductive path in the composites, and the nanosized functionalized Al₂O₃ (n‐f‐Al₂O₃) act as connection role to provide additional channels for the heat flow. The thermal conductivity of the f‐Al₂O₃/PEN‐t‐ph composites were investigated as a function of n‐f‐Al₂O₃ loading. Also, a remarkable improvement of the thermal conductivity from 0.206 to 0.467 W/mK was achieved at 30 wt % n‐f‐Al₂O₃ loading, which is nearly 2.7‐fold higher than that of pure PEN‐t‐ph polymer. Furthermore, the mechanical testing reveals that the tensile strength increased from 99 MPa for pure PEN‐t‐ph to 105 MPa for composites with 30 wt % m‐f‐Al₂O₃ filler loading. In addition, the PEN‐t‐ph composites possess excellent thermal properties with glass transition temperature (T_g) above 184°C, and initial degradation temperature (T_id) over 490°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41595.     

Estimation of thermal conductivity of polymer multiphase composites

The thermal conductivities of a medium density polyethylene composites filled separately with two different thermal conductive fillers including graphite, cuprum, and aluminum oxide (Al₂O₃), an epoxy composites filled respectively with two different thermal conductive fillers including silicon nitride, aluminum hydroxide, Al₂O₃ and aluminum nitride, and a polypropylene composites filled with aluminum hydroxide and magnesium hydroxide were estimated using a thermal conductivity equation of polymer multiphase composites. This equation was based on a new heat transfer model, and the parameters were easily determined. It was found that the estimated thermal conductivities of the three composites systems were approximately close to the experimental measured data reported in literature. In addition, the predictions were roughly close to the estimations from the Agari model. POLYM. ENG. SCI., 57:965–972, 2017. © 2016 Society of Plastics Engineers     

Mechanical and thermal properties of spark plasma sintered Al2O3-graphene-SiC hybrid composites

Monolithic Al₂O₃ and Al₂O₃-graphene-SiC hybrid composites were prepared by spark plasma sintering (SPS) under vacuum atmosphere. The results show that the hybrid composites were almost completely dense (>97%). SiC content has a significant effect on the microstructure of the composites. With the increase of SiC content, the average grain size of alumina decreased gradually. The addition of SiC to alumina changed fracture mode from inter-granular fracture to mixed fracture mode of inter-granular fracture and trans-granular fracture. The Al₂O₃-0.4 wt%graphene-5 wt% SiC hybrid composite has the highest bending strength and hardness, which were 57% and 19.22% higher than those of the monolithic alumina, respectively. The room temperature (RT) thermal conductivity of the monolithic Al₂O₃ (25.5 W/m·K) was the highest. The thermal conductivity and thermal diffusivity coefficient of the composites decreased with the increase in temperature, while the specific heat of monolithic alumina and composites increased with the increase in temperature and additives. These properties were related to the microstructure of materials and the possible transport mechanisms were discussed.     

Design and fabrication of electro‐conductive polymer nanocomposites with mechanical and thermal resistance

The commencement of the industrial revolution paved the way for the fabrication of flexible polymers with high‐strength metalloceramics as novel materials of all kinds. Fabricating metal–ceramic/polymer conductive composites is one such dimension followed for the present research work making use of the properties of the three components. Electroless deposition, for permanent metallic coating, was performed to coat Al₂O₃ with metallic Cu followed by the inclusion of the Cu–Al₂O₃ filler into a poly(vinyl chloride) (PVC) matrix. X‐ray diffraction and energy‐dispersive X‐ray studies predicted a prominent growth of metallic Cu crystallites onto Al₂O₃ with an increased average size and variation in elemental composition, respectively, when compared to pristine Al₂O₃. Morphological behaviour via scanning electron microscopy also envisioned uniform Cu coating onto Al₂O₃ and a homogeneous dispersion throughout the polymer matrix. When incorporated into PVC, electrical conductivity analysis highlighted a distinct variation in composite phases from insulating (7.14 × 10^?16 S cm^?1) to semiconducting behaviour (8.33 × 10^?5 S cm^?1) as a function of Cu–Al₂O₃ filler. Mechanical behaviour (tensile strength, Young's modulus and elongation at break) and thermal properties of the prepared composites also indicated a substantial improvement in material strength with Cu–Al₂O₃ incorporation. The enhanced electrical conductivity along with improved thermomechanical status with significant filler–matrix interaction permits the potential usage of such novel composites in a range of state‐of‐the‐art semiconducting electronic devices. © 2018 Society of Chemical Industry     

Synthesis of a novel biphenyl epoxy resin and its hybrid composite with high thermal conductivity

A novel biphenyl epoxy monomer of p-methyl phenylhydroquinone epoxy resin (p-MEP) was synthesized and characterized. We researched its potential in the area of thermal conduction application and prepared a series of hybrid composites based on it with different mass ratios of sphere Al₂O₃ filler. From the good mobility and low viscosity of p-MEP, it allowed mixing with more Al₂O₃ fillers. The hybrid epoxy resins owned the advantages of traditional epoxy resins as well as quite considerable thermal conductivity. Therefore, the hybrid composite at the maximum mass fraction of 70% possess the highest thermal conductivity of 5.6 W mK⁻¹, which is 5.6 times higher than that of pristine p-MEP (0.1 W mK⁻¹). © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47078.     

Simultaneously enhanced mechanical properties and thermal properties of ultrahigh‐molecular‐weight polyethylene with polydopamine‐coated α‐alumina platelets

Polydopamine (PDA) was employed to modify micrometric Al₂O₃ platelets to improve the interfacial compatibility between α‐Al₂O₃ powder and ultrahigh‐molecular‐weight polyethylene (UHMWPE). The structure of PDA‐coated Al₂O₃ and UHMWPE composites was investigated via Fourier transform infrared spectroscopy, scanning electron microscopy and X‐ray photoelectron spectroscopy. The thermal stability and mechanical performance of the samples were also evaluated. It is clear that UHMWPE/PDA‐Al₂O₃ composites exhibit better mechanical properties, higher thermal stability and higher thermal conductivity than UHMWPE/Al₂O₃ composites, owing to the good dispersion of Al₂O₃ powder in the UHMWPE matrix and the strong interfacial force between the macromolecules and the inorganic filler caused by the presence of PDA. The tensile strength and the tensile elongation at break of UHMWPE/PDA‐Al₂O₃ composite with 1 wt% PDA‐Al₂O₃ are 62.508 MPa and 462%, which are 1.96 and 1.98 times higher than those of pure UHMWPE, respectively. The thermal conductivity of UHMWPE/PDA‐Al₂O₃ composite increases from 0.38 to 0.52 W m^?1 K^?1 with an increase in the dosage of PDA‐Al₂O₃ to 20 wt%. The results show that the prepared PDA‐coated Al₂O₃ powder can simultaneously enhance the mechanical properties and thermal conductivity of UHMWPE. © 2018 Society of Chemical Industry     

Influence of filler type and content on thermal conductivity and mechanical properties of thermoplastic compounds

Combining thermal conductivity with electrical isolation is a very interesting topic for electronic applications in order to transfer the generated heat. Typical approaches combine thermally conductive fillers with a thermoplastic matrix. The aim of this work was to investigate the influence of different fillers and matrices on the thermal conductivity of the polymer matrix composites. In this study, various inorganic fillers, including aluminum oxide (Al₂O₃), zinc oxide (ZnO), and boron nitride (BN) with different shapes and sizes, were used in matrix polymers, such as polyamide 6 (PA6), polypropylene (PP), polycarbonate (PC), thermoplastic polyurethane (TPU), and polysulfone (PSU), to produce thermally conductive polymer matrix composites by compounding and injection molding. Using simple mathematical models (e.g., Agari model, Lewis–Nielson model), a first attempt was made to predict thermal conductivity from constituent properties. The materials were characterized by tensile testing, density measurement, and thermal conductivity measurement. Contact angle measurements and the calculated surface energy can be used to evaluate the wetting behavior, which correlates directly with the elastic modulus. Based on the aforementioned evaluations, we found that besides the volume fraction, the particle shape in combination with the intrinsic thermal conductivity of the filler has the greatest influence on the thermal conductivity of the composite.