Design Paradigm Utilizing Reversible Diels-Alder Reactions to Enhance the Mechanical Properties of 3D Printed Materials.

A design paradigm is demonstrated that enables new functional 3D printed materials made by fused filament fabrication (FFF) utilizing a thermally reversible dynamic covalent Diels-Alder reaction to dramatically improve both strength and toughness via self-healing mechanisms. To achieve this, we used as a mending agent a partially cross-linked terpolymer consisting of furan-maleimide Diels-Alder (fmDA) adducts that exhibit reversibility at temperatures typically used for FFF printing. When this mending agent is blended with commercially available polylactic acid (PLA) and printed, the resulting materials demonstrate an increase in the interfilament adhesion strength along the z-axis of up to 130%, with ultimate tensile strength increasing from 10 MPa in neat PLA to 24 MPa in fmDA-enhanced PLA. Toughness in the z-axis aligned prints increases by up to 460% from 0.05 MJ/m(3) for unmodified PLA to 0.28 MJ/m(3) for the remendable PLA. Importantly, it is demonstrated that a thermally reversible cross-linking paradigm based on the furan-maleimide Diels-Alder (fmDA) reaction can be more broadly applied to engineer property enhancements and remending abilities to a host of other 3D printable materials with superior mechanical properties.

[1]  Yinghua Jin,et al.  Recent advances in dynamic covalent chemistry. , 2013, Chemical Society reviews.

[2]  S. Nutt,et al.  A Thermally Re-mendable Cross-Linked Polymeric Material , 2002, Science.

[3]  Kim K. Oehlenschlaeger,et al.  State‐of‐the‐Art Analytical Methods for Assessing Dynamic Bonding Soft Matter Materials , 2014, Advanced materials.

[4]  M. Mastalerz.  Shape-persistent organic cage compounds by dynamic covalent bond formation. , 2010, Angewandte Chemie.

[5]  Amanda C. Engler,et al.  Dual-Responsive Hydrogels for Direct-Write 3D Printing , 2015 .

[6]  M. Urban,et al.  Dynamic materials: The chemistry of self-healing. , 2012, Nature chemistry.

[7]  R. Boutelle,et al.  Substituent effects on the reversibility of furan-maleimide cycloadditions. , 2011, The Journal of organic chemistry.

[8]  C. Highley,et al.  Direct 3D Printing of Shear‐Thinning Hydrogels into Self‐Healing Hydrogels , 2015, Advanced materials.

[9]  N. Sottos,et al.  Autonomic healing of polymer composites , 2001, Nature.

[10]  A. Gandini,et al.  Materials from renewable resources based on furan monomers and furan chemistry: work in progress , 2009 .

[11]  J Fraser Stoddart,et al.  Template-directed synthesis employing reversible imine bond formation. , 2007, Chemical Society reviews.

[12]  Julian R. Jones,et al.  3D Printing of Biocompatible Supramolecular Polymers and their Composites. , 2016, ACS applied materials & interfaces.

[13]  M. P. Stevens,et al.  Thermally reversible crosslinking of polystyrene via the furan-maleimide diels-alder reaction , 1992 .

[14]  C. Kappe,et al.  Synthetic applications of furan Diels-Alder chemistry , 1997 .

[15]  Karen L. Wooley,et al.  Model Diels-Alder Studies for the Creation of Amphiphilic Cross-Linked Networks as Healable, Antibiofouling Coatings. , 2012, ACS macro letters.

[16]  H. Durmaz,et al.  Linear tetrablock quaterpolymers via triple click reactions, azide‐alkyne, diels–alder, and nitroxide radical coupling in a one‐pot fashion , 2011 .

[17]  A. Adronov,et al.  Effect of spacer chemistry on the formation and properties of linear reversible polymers , 2013 .

[18]  H. Sodano,et al.  Self‐Healing Polyurethanes with Shape Recovery , 2014 .

[19]  D. McGrath,et al.  Thermally reversible dendronized linear ab step-polymers via "click" chemistry , 2011 .

[20]  Xinling Wang,et al.  Polyether–maleimide‐based crosslinked self‐healing polyurethane with Diels–Alder bonds , 2015 .

[21]  Matthew Di Prima,et al.  On reducing anisotropy in 3D printed polymers via ionizing radiation , 2014 .

[22]  J. Stampfl,et al.  Rapid formation of regulated methacrylate networks yielding tough materials for lithography-based 3D printing , 2016 .

[23]  Christopher N. Bowman,et al.  A Dual-Cure, Solid-State Photoresist Combining a Thermoreversible Diels–Alder Network and a Chain Growth Acrylate Network , 2014 .

[24]  Youchun Zhang,et al.  Thermally Self-Healing Polymeric Materials : The Next Step to Recycling Thermoset Polymers? , 2009 .

[25]  Nabarun Roy,et al.  DYNAMERS: dynamic polymers as self-healing materials. , 2015, Chemical Society reviews.

[26]  S. Rowan,et al.  Using the dynamic bond to access macroscopically responsive structurally dynamic polymers. , 2011, Nature materials.

[27]  Hod Lipson,et al.  Fabricated: The New World of 3D Printing , 2013 .

[28]  M. Sherwood,et al.  Thermally Induced Nanoimprinting of Biodegradable Polycarbonates Using Dynamic Covalent Cross-Links. , 2013, ACS macro letters.

[29]  B. Sumerlin,et al.  Future perspectives and recent advances in stimuli-responsive materials , 2010 .

[30]  Z. Eckel,et al.  Additive manufacturing of polymer-derived ceramics , 2016, Science.

[31]  Qian Tian,et al.  Simple, Cost-Effective 3D Printed Microfluidic Components for Disposable, Point-of-Care Colorimetric Analysis , 2016 .

[32]  N. Yoshie,et al.  Bio-Based Furan Polymers with Self-Healing Ability , 2013 .

[33]  N. Wagner,et al.  Dynamic Bonds in Covalently Crosslinked Polymer Networks for Photoactivated Strengthening and Healing , 2015, Advanced materials.

[34]  Philip J. Kitson,et al.  Integrated 3D-printed reactionware for chemical synthesis and analysis. , 2012, Nature chemistry.

[35]  Leroy Cronin,et al.  Combining 3D printing and liquid handling to produce user-friendly reactionware for chemical synthesis and purification , 2013 .

[36]  P. Bártolo,et al.  Additive manufacturing of tissues and organs , 2012 .

[37]  Scott R. White,et al.  Autonomic Healing of Polymers , 2008 .

[38]  David Dean,et al.  Evaluating 3D‐Printed Biomaterials as Scaffolds for Vascularized Bone Tissue Engineering , 2015, Advanced materials.

[39]  M. Shoichet,et al.  Diels-Alder Click cross-linked hyaluronic acid hydrogels for tissue engineering. , 2011, Biomacromolecules.

[40]  Ling Zhang,et al.  Fabrication of Highly Stretchable Conductors Based on 3D Printed Porous Poly(dimethylsiloxane) and Conductive Carbon Nanotubes/Graphene Network. , 2016, ACS applied materials & interfaces.

[41]  Wayne Hayes,et al.  Healable polymeric materials: a tutorial review. , 2010, Chemical Society reviews.

[42]  M. Panhuis,et al.  An overview of the suitability of hydrogel-forming polymers for extrusion-based 3D-printing. , 2015, Journal of materials chemistry. B.

[43]  Brian J. Adzima,et al.  3D Photofixation Lithography in Diels-Alder Networks. , 2012, Macromolecular rapid communications.