The toughness of network polymers can be improved by adding supramolecular interactions, such as interchain hydrogen bonding (H-bonding). Polyurethane (PU), discovered in the 1940s, is now ubiquitously used as a high-performance polymer; PU contains H-bonds between N-H (donor) and C=O (acceptor) groups on the urethane (carbamate) linkages. The supramolecular H-bonding enhances toughness in network PU. As an example of including urethane linkages in polymer networks, materials used in vat photopolymerization 3D printing are capable of moderate plastic deformations, with a tensile strength of 30-40 MPa and an elongation-at-break of ~50%. We hypothesize that enhanced H-bonding may further strengthen the supramolecular interactions for enhanced toughness. In addition, PU unavoidably relies on highly toxic isocyanate feedstock chemicals, and many efforts have made to reduce their consumption. We sought to significantly improve the toughness of network polymers by introducing amide linkages. Polyamide, first invented by Wallace Carothers and commercialized by Dow under the tradename Nylon, is one of the classic polymers. Comparing an amide to a urethane group, the carbonyl group in the amide is more electron-withdrawing so that the proton is more available for forming H-bonds. The stronger H-bonding is evident in the higher melting temperatures (Tm) of amides than their urethane counterparts, in mono-and di-functional molecules, and linear polymers (Figure ). Surprisingly, the study of network polyamides has been scarce, likely due to synthetic inconvenience. Amides are commonly formed by condensation reactions between carboxylic acid (or acid chloride) and amines, or nucleophilic addition of amines to esters (or anhydrides). In both cases, small molecules must be removed to drive the reaction equilibrium towards the formation of high molecular weight polymers. However, the elimination of small molecules is impractical for synthesizing neat network polymers, since diffusivity becomes prohibited. To this end, our approach to obtain ductile glassy networks is centered on meticulously designed network polyamides synthesized by thiol-ene photopolymerization reactions. Thiol-ene photopolymerization has been demonstrated to be useful in synthesizing network polymers with homogeneous network structures and functionality. Thiol-ene polymerizations proceed in a step-growth fashion by free-radical mediated addition reactions. Work from Hoyle, Savin, and Bowman has shown moderately tough materials by incorporation of urethane, thiourethane, and triazole group in the thiol-ene networks, respectively. We sought to synthesize amide containing multifunctional allyl monomers to obtain network polyamides. Hakkarainen et al. reported thiol-ene polyamide networks using an diallyl terephthalamide monomer, though only brittle materials were obtained. In this work, we aim to study the effect of H-bonding from various amide groups and the effect of crosslinking density on ductility. We target a 4 between the two traditional network polymers. (B) A cartoon showing a strained H-bonding network capable of large strain at below Tg and elastic recovery at above Tg.