The composites of cross-linked polyethylene with enhanced thermal conductivity

• Published in: Journal of thermal analysis and calorimetry Vol. 149; no. 10; pp. 4385 - 4396
• Main Authors: Latko-Durałek, Paulina, Sałasińska, Kamila, Kubiś, Michał, Kozera, Paulina, Pietrak, Karol, Rojewski, Szymon, Jurczyk-Kowalska, Magdalena, Szlązak, Karol, Łapka, Piotr, Boczkowska, Anna
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 2024; Springer Nature B.V
• Subjects: Analytical Chemistry; Boron nitride; Chemistry; Chemistry and Materials Science; Composite materials; Cross-linked polyethylene; Fillers; Graphite; Heat conductivity; Heat transfer; Inorganic Chemistry; Measurement Science and Instrumentation; Mechanical properties; Modulus of rupture in bending; Multi wall carbon nanotubes; Physical Chemistry; Polyethylene; Polymer Sciences; Thermal conductivity; Cross-linked polyethylene; Thermal properties; Polymer matrix composites; Analytical Modeling; Particle-reinforcement
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-024-13000-2

This paper describes the composites of silane cross-linked polyethylene (PEX b ) mixed with four different fillers dedicated to improving thermal conductivity, such as multi-walled carbon nanotubes, graphite, boron nitride, and mineral filler. Using the mathematical modeling, the concentration of each filler was estimated to reach the value of 0.675 W m −1 K −1 suitable for the usage PEX b in the production of geothermal pipes. From tested fillers, all improve the thermal conductivity of pure PEX b ; however, above the required value, only 28 mass% of boron nitride (0.937 W m −1 K −1 ). It was associated with its perfect dispersion and the highest gel content achieved, also resulting in the highest flexural modulus. Graphite at 5 mass% and mineral filler at 35 mass% allowed the thermal conductivity to equal 0.622 W m −1 K −1 and 0.624 W m −1 K −1 , respectively, with a simultaneous medium effect on the mechanical properties. Carbon nanotubes increased PEX's conductivity to a small extent, due to their occurrence as agglomerates.