3D Printing of Polymer Nanocomposites via Stereolithography

Abstract

Additive manufacturing (AM) is still underutilized as an industrial process, but is quickly gaining momentum with the development of innovative techniques and materials for various applications. In particular, stereolithography (SLA) is now shifting from rapid prototyping to rapid manufacturing, but is facing challenges in parts performance and printing speed, among others. This review discusses the application of SLA for polymer nanocomposites fabrication to show the technology's potential in increasing the applicability of current SLA‐printed parts. Photopolymerization chemistry, nanocomposite preparation, and applications in various industries are also explained to provide a comprehensive picture of the current and future capabilities of the technique and materials involved.

3D Printing/Interfacial Polymerization Coupling for the Fabrication of Conductive Hydrogel

“…Another 3D printing process based on spatially controlled solidification of a liquid resin by photopolymerization is digital light processing (DLP). Instead of using a laser to “draw” the object under a point‐by‐point manner like in SLA, DLP equipment projects an entire slice of an object using a digital projector . Both techniques provide powerful tools to fabricate complex 3D polymeric structures, with good resolution and fast production times especially in the case of DLP.…”

Printing Polymer Nanocomposites and Composites in Three Dimensions

“…A homogeneous dispersion of nanomaterials and an acceptable viscosity of materials are desirable when nanocomposites are used. [17] SLA printing of nanocomposites have comprehensively been reviewed by Manapat et al [20] Further advances in the stereolithography led to the development of a more precise technique based on two-photon polymerization (TPP), developed by Japanese researchers [21] that enables the fabrication of very fine features (resolution of 100 nm). Here, a laser beam is focused onto a very small volume of a photopolymer by the utilization of a high numerical aperture objective.…”

“…For example, polylactide is a commonly-used materials for bio-related applications, but it is not photosensitive in its untreated state. [20] The selective laser sintering (SLS) technique is one of the powder bed technologies, which was developed by a team at the University of Texas Austin [25] in the mid-1980s. The SLS consists of selectively sintering thin layers of powdered materials (e.g., thermoplastics) by a controlled scanning laser beam, usually a CO 2 laser, according to the sliced pattern.…”

“…Upon creation of the first layer, another layer of the powder is laid down and the process is repeated until a desired 3D structure is built. Biomedical applications, tissue engineering [17][18][19][20] Optical projection SLA Similar to the SLA, but uses dynamic photomasks (with designed patterns for each layer) which are produced by a digital mirror device Photopolymers (UV-curable)…”

“…Solution mixing using sonication method is another option, where the polymer matrix can be dissolved in the solvent. [20,35] PolyJet inkjet printing and direct-write extrusion-based techniques are powerful alternatives to the conventional techniques mentioned above. Unlike other inkjet printing techniques in which low viscosity solutions or polymer suspensions are used as printing materials, the PolyJet technique, developed by Objet in 2000, [41] uses photopolymers and their associated nanocomposites to inkjet print truly 3D structures with a resolution of %30 mm in a layer-by-layer fashion.…”