Photo-chemically induced polycondensation of a pure phenolic resin for additive manufacturing

Abstract

Bakelite© or phenoplasts are considered the first synthetic polymers in the world. These resins, produced by polycondensation, have always been known for their chemical resistance, excellent flame resistance and thermal...

Matching Low Viscosity with Enhanced Conductivity in Vat Photopolymerization 3D Printing: Disparity in the Electric and Rheological Percolation Thresholds of Carbon-Based Nanofillers Is Controlled by the Matrix Type and Filler Dispersion

“…29 Such materials are conveniently printed at elevated temperatures, reducing their high viscosity. 43 The percolation threshold, marked by an abrupt increase of η 1 Hz , was observed already at 0.25 and 0.5% of dispersed MWCNTs and CB, respectively. Indeed, anisotropic nanotubes are expected to percolate at a lower concentration than the more isotropic CB.…”

“…Carbonaceous fillers worsened the double bond conversion due to intense light absorption (Table S4). 43 The FTIR−ATR spectroscopy is a surface-specific technique, and a slightly different curing profile might be expected in bulk.…”

Additive manufacturing of high-performance polycyanurates via photo-induced catalytic poly-trimerization

“…The additive manufacturing technology required for this approach is Hot Lithography. 21 Using a heated vat and platform, various new materials can be 3D printed layer-by-layer, which was not possible before, including oxazolines, 22 lactones, 23 bakelite® 24 and furan-based resins. 25 In this article, by exploiting this technique with the system previously described, we show that we have been able to expand the possibilities of 3D printing by adding a category in the high-performance range, with the disadvantage for applications that have a sensitivity to iron atoms, since for the formulation presented here, the coordinative center remains in the cured product.…”

Cationic photopolymerization of cyclic esters at elevated temperatures and their application in hot lithography

“…However, even though the initial aim of this approach was to increase the processability of viscous compounds at temperatures up to 120 °C, it is also a possibility to increase the polymerization rate of monomers with moderate reactivity at ambient temperatures. With this technique even novolaks have already been used in additive manufacturing 3 . One group of monomers, which is abundantly used and crucial in many applications where biocompatibility or biodegradability is required, are cyclic esters.…”

“…With this technique even novolaks have already been used in additive manufacturing. 3 One group of monomers, which is abundantly used and crucial in many applications where biocompatibility or biodegradability is required, are cyclic esters. While it is common to polymerize them via anionic ring-opening polymerization, the use of cationic ring-opening polymerization (CROP) is less investigated.…”