Emerging 3D printed thermal insulating materials for sustainable approach: A review and a way forward

Abstract

Thermal insulating materials are such materials that do not allow the movement of heat through themselves. The material must have lower thermal conductivity to work efficiently as an insulator. Conventionally glass wool, calcium silicates, concrete, and processed wood particle boards are well‐known thermal insulators used for construction purposes. The thermal conductivity of glass wool is near about ~0.02–0.04 W/mK, and calcium silicates are also around ~0.08 W/mK. In contrast to these fabrication techniques, 3D printing or additive manufacturing has emerged as the most in‐demand fabrication method. The scope of versatility in shapes, design, dimension, and finish that 3D printing yields are enormous, and their performance is significantly comparable and, in some cases, better than conventionally prepared materials. 3D printing includes various methods such as FDM, SLA, SLS, DIW, and so on. Recent literature has shown the fabrication of thermally insulating material using raw materials like silk fiber, fly ash, cement, polymer composite, metal oxides, and so on, through additive manufacturing. These materials have very low thermal conductivity, as low as 0.03–0.08 W/mK for SLA and DIW printed silivoxel, cellulose nanocrystals composites having 0.08–0.09 W/mK and 0.04 for PU and cork composites. The low thermal conductivity values indicate their possible and efficient application as thermal insulators.

3D Printed Liquid Crystal Polymer Thermosiphon for Heat Transfer under Vacuum

“…Polymers can serve as effective insulating materials, particularly when designed with higher porosity. [54,55] However, here we propose a heat transfer component by integrating a polymer-based thermosiphon within a building façade to selectively insulate and conduct heat depending on the outdoor and indoor conditions. The proposed façade would reduce the demand for building heating and cooling systems, comprising nearly half of the CO 2 emissions of global building stock (30% of global emissions) [56] while maintaining a comfortable indoor environment for occupants.…”

3D printed honeycomb bilayer structures based on polylactic acid as lightweight microwave absorbing materials

“…Porous structures as aerogels, 21,22 foams, 23,24 and others, comprised of polymer matrices filled with appropriate dielectric/magnetic particles may also provide additional decreasing of density and better flexibility to the resulting material. Polymeric porous composites with designed geometries can be easily developed by using additive manufacturing (AM), or 3D printing, technologies 25 . Among several types of AMs, material extrusion (MEX) is one of the more affordable, process friendly option and material versatile, allowing the choice of material that better suit specific application 25,26 .…”

“…Polymeric porous composites with designed geometries can be easily developed by using additive manufacturing (AM), or 3D printing, technologies. 25 Among several types of AMs, material extrusion (MEX) is one of the more affordable, process friendly option and material versatile, allowing the choice of material that better suit specific application. 25,26 Moreover, the use of MEX allows the empiric study of the material or geometry in question without large delay, which is highly advantageous for nonhomogenous composites that are hard to simulate.…”

“…25 Among several types of AMs, material extrusion (MEX) is one of the more affordable, process friendly option and material versatile, allowing the choice of material that better suit specific application. 25,26 Moreover, the use of MEX allows the empiric study of the material or geometry in question without large delay, which is highly advantageous for nonhomogenous composites that are hard to simulate. Some works have explored this technology to produce components for EMI shielding applications by using PLA, ABS, PP, PE, PAEK, POE among others conductive filaments.…”