Recent Progress in Applications of the Cold Sintering Process for Ceramic–Polymer Composites

Abstract

Ceramic-polymer composites are of interest for designing enhanced and unique properties. However, the processing temperature windows of sintering ceramics are much higher than that of compaction, extrusion, or sintering of polymers, and thus traditionally there has been an inability to cosinter ceramic-polymer composites in a single step with high amounts of ceramics. The cold sintering process is a low-temperature sintering technology recently developed for ceramics and ceramic-based composites. A wide variety of ceramic materials have now been demonstrated to be densified under the cold sintering process and therefore can be all cosintered with polymers from room temperature to 300 °C. Here, the status, understanding, and application of cold cosintering, with different examples of ceramics and polymers, are discussed. One has to note that these types of cold sintering processes are yet new, and a full understanding will only emerge after more ceramic-polymer examples emerge and different research groups build upon these early observations. The general processing, property designs, and an outlook on cold sintering composites are outlined. Ultimately, the cold sintering process could open up a new multimaterial design space and impact the field of ceramic-polymer composites.

Thermosetting polymers in cold sintering: The fabrication of ZnO‐polydimethylsiloxane composites

“…Recently, several studies have highlighted the possibility to fabricate ceramic-thermoplastic polymers composites by the cold sintering process (CSP). [1][2][3][4][5][6][7] The CSP is a technique that enables the fabrication of dense ceramics and ceramic-based composites at low temperature (<350°C), mainly based on a pressure solution creep mechanism (dissolution → mass transport → precipitation, following chemical potential gradients), induced by the presence of a transient liquid phase and uniaxial pressure. [8][9][10][11][12][13][14][15] CSP bridges the gap between processing temperatures of an important number of ceramics and polymers, offering a unique opportunity for the discovery, design, and fabrication of new composites with engineered grain boundaries.…”

“…Recently, several studies have highlighted the possibility to fabricate ceramic‐thermoplastic polymers composites by the cold sintering process (CSP) . The CSP is a technique that enables the fabrication of dense ceramics and ceramic‐based composites at low temperature (<350°C), mainly based on a pressure solution creep mechanism (dissolution → mass transport → precipitation, following chemical potential gradients), induced by the presence of a transient liquid phase and uniaxial pressure .…”

Cold sintering and microwave dielectric properties of dense HBO2‐II ceramics

“…On the other hand, a new sintering method known as “cold sintering” has attracted extensive attention after its appearance in 2014, since many ceramics can be densified by this method at extremely low temperatures from room temperature to 300°C . Cold sintering is also very attractive for the low‐temperature preparation of ceramic‐polymer and ceramic‐ceramic composites . For a regular cold sintering process, the ceramic powder is mixed with a small amount of transient liquid phase (usually water) in which the ceramic is soluble, and a uniaxial pressure is applied on the mixture.…”

“…[18][19][20] Cold sintering is also very attractive for the low-temperature preparation of ceramic-polymer and ceramic-ceramic composites. 21,22 For a regular cold sintering process, the ceramic powder is mixed with a small amount of transient liquid phase (usually water) in which the ceramic is soluble, and a uniaxial pressure is applied on the mixture. The transient liquid phase activates the dissolution-precipitation mechanism and accelerates the mass transport greatly, so that the densification of the ceramics can be realized easily near the evaporation temperature of the transient solvent.…”

Femtosecond Optical Annealing Induced Polymer Melting and Formation of Solid Droplets

“…Efficiencies have been largely improved in polymeric optoelectronic devices with the development of new materials, new designs, and new processing techniques [4,5,6]. Deep insights into the physics, new designs of the device structures, and surface/interfacial processing of the thin-film polymer are always within the important research topics [7,8,9,10,11]. Photophysical and photoelectronic properties of polymer semiconductors can be tailored by changing the fabrication process [7,8,9] or the decorative strategies, such as the annealing processes, the additive solvent treatment, or the laser irradiation [10,11,12].…”