{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/155850"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/155850","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Method for Photopolymerization 3D Printing of Recyclable Thermoplastic Polymers","abstract":"Conventional light-based processes used in additive manufacturing (AM), such as vat polymerization, yield non-recyclable thermoset polymers, which pose sustainability issues at scale. This thesis studies a method for photopolymerization 3D printing of the common polymers polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) to address the growing demand for low-waste production of high-resolution polymer parts with complex geometries in industrial-scale manufacturing. This new approach not only produces directly recyclable linear thermoplastic polymers but also enables the light-based printing of polymers soluble in their own monomer. It was previously demonstrated by Chazot et al. that photo-defined layers of polyacrylonitrile (PAN) can be formed at a liquid-liquid interface; this technique was named interfacial photopolymerization (IPP). In this thesis, which focuses on multilayer 3D printing (3D-IPP), the resolution and stability of layers formed by IPP are improved using a light-absorbing dye while incorporating a water-soluble polyethylene glycol binder to improve yield, printing speed, and mechanical properties. Joint initiation using commercial water-soluble photoinitiators V-50 and LAP, along with the addition of HCL and CaCl2, further enhances printing performance by producing dense layers and reducing voids. Post-processing techniques are devised to preserve part geometry after printing, including controlled air drying, thermal post-processing with PEG infiltration, and the inclusion of compatible polymeric binders in the printing composition to minimize cracking and shrinkage. Additionally, hardware is developed to integrate the IPP process into a commercial projector-based 3D printer, demonstrating compatibility of the proposed chemistry with off-the-shelf hardware. The capability to digitally manufacture high resolution 3D structures with IPP is demonstrated and the physical properties of the resulting composite polymer are characterized. While 3D-IPP cannot yet directly rival conventional manufacturing methods, the benign aqueous chemistry as well as recyclability and circularity of produced parts offers a promising path towards sustainable and resource-efficient AM as the technology matures.","abstract_html":"Conventional light-based processes used in additive manufacturing (AM), such as vat polymerization, yield non-recyclable thermoset polymers, which pose sustainability issues at scale. This thesis studies a method for photopolymerization 3D printing of the common polymers polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) to address the growing demand for low-waste production of high-resolution polymer parts with complex geometries in industrial-scale manufacturing. This new approach not only produces directly recyclable linear thermoplastic polymers but also enables the light-based printing of polymers soluble in their own monomer. It was previously demonstrated by Chazot et al. that photo-defined layers of polyacrylonitrile (PAN) can be formed at a liquid-liquid interface; this technique was named interfacial photopolymerization (IPP). In this thesis, which focuses on multilayer 3D printing (3D-IPP), the resolution and stability of layers formed by IPP are improved using a light-absorbing dye while incorporating a water-soluble polyethylene glycol binder to improve yield, printing speed, and mechanical properties. Joint initiation using commercial water-soluble photoinitiators V-50 and LAP, along with the addition of HCL and CaCl2, further enhances printing performance by producing dense layers and reducing voids. Post-processing techniques are devised to preserve part geometry after printing, including controlled air drying, thermal post-processing with PEG infiltration, and the inclusion of compatible polymeric binders in the printing composition to minimize cracking and shrinkage. Additionally, hardware is developed to integrate the IPP process into a commercial projector-based 3D printer, demonstrating compatibility of the proposed chemistry with off-the-shelf hardware. The capability to digitally manufacture high resolution 3D structures with IPP is demonstrated and the physical properties of the resulting composite polymer are characterized. While 3D-IPP cannot yet directly rival conventional manufacturing methods, the benign aqueous chemistry as well as recyclability and circularity of produced parts offers a promising path towards sustainable and resource-efficient AM as the technology matures.","abstract_has_math":false,"creators":["Tumkur Mahesh, Prajwal"],"institution":"Massachusetts Institute of Technology","degree_name":"Master","degree_level":null,"degree_discipline":null,"degree_department":"Massachusetts Institute of Technology. Department of Mechanical Engineering","school":null,"contributors":[],"advisors":["Hart, A. John"],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024-05","date_published":"2024-05","updated_at":"2026-07-22T22:22:04Z","subjects":[],"languages":[],"rights":["Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)","Copyright retained by author(s)"],"rights_urls":["https://creativecommons.org/licenses/by-sa/4.0/"],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/1721.1/155850","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Hart, A. John"]},{"key":"dc:contributor.department","label":"Department","values":["Massachusetts Institute of Technology. Department of Mechanical Engineering"]},{"key":"dc:creator","label":"Author","values":["Tumkur Mahesh, Prajwal"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2024-08-01T19:01:07Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2024-08-01T19:01:07Z"]},{"key":"dc:date.issued","label":"Date","values":["2024-05"]},{"key":"dc:publisher","label":"Institution","values":["Massachusetts Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master","Master of Science in Mechanical Engineering"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)","Copyright retained by author(s)"]},{"key":"dc:rights.uri","label":"Rights URI","values":["https://creativecommons.org/licenses/by-sa/4.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/1721.1/155850"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Conventional light-based processes used in additive manufacturing (AM), such as vat polymerization, yield non-recyclable thermoset polymers, which pose sustainability issues at scale. This thesis studies a method for photopolymerization 3D printing of the common polymers polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) to address the growing demand for low-waste production of high-resolution polymer parts with complex geometries in industrial-scale manufacturing. This new approach not only produces directly recyclable linear thermoplastic polymers but also enables the light-based printing of polymers soluble in their own monomer. It was previously demonstrated by Chazot et al. that photo-defined layers of polyacrylonitrile (PAN) can be formed at a liquid-liquid interface; this technique was named interfacial photopolymerization (IPP). In this thesis, which focuses on multilayer 3D printing (3D-IPP), the resolution and stability of layers formed by IPP are improved using a light-absorbing dye while incorporating a water-soluble polyethylene glycol binder to improve yield, printing speed, and mechanical properties. Joint initiation using commercial water-soluble photoinitiators V-50 and LAP, along with the addition of HCL and CaCl2, further enhances printing performance by producing dense layers and reducing voids. Post-processing techniques are devised to preserve part geometry after printing, including controlled air drying, thermal post-processing with PEG infiltration, and the inclusion of compatible polymeric binders in the printing composition to minimize cracking and shrinkage. Additionally, hardware is developed to integrate the IPP process into a commercial projector-based 3D printer, demonstrating compatibility of the proposed chemistry with off-the-shelf hardware. The capability to digitally manufacture high resolution 3D structures with IPP is demonstrated and the physical properties of the resulting composite polymer are characterized. While 3D-IPP cannot yet directly rival conventional manufacturing methods, the benign aqueous chemistry as well as recyclability and circularity of produced parts offers a promising path towards sustainable and resource-efficient AM as the technology matures."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["S.M."]},{"key":"dc:title","label":"Title","values":["Method for Photopolymerization 3D Printing of Recyclable Thermoplastic Polymers"]}]}],"canonical_facts":{"dc:contributor.advisor":["Hart, A. John"],"dc:contributor.department":["Massachusetts Institute of Technology. Department of Mechanical Engineering"],"dc:creator":["Tumkur Mahesh, Prajwal"],"dc:date.accessioned":["2024-08-01T19:01:07Z"],"dc:date.available":["2024-08-01T19:01:07Z"],"dc:date.issued":["2024-05"],"dc:description.abstract":["Conventional light-based processes used in additive manufacturing (AM), such as vat polymerization, yield non-recyclable thermoset polymers, which pose sustainability issues at scale. This thesis studies a method for photopolymerization 3D printing of the common polymers polyacrylonitrile (PAN) and polymethyl methacrylate (PMMA) to address the growing demand for low-waste production of high-resolution polymer parts with complex geometries in industrial-scale manufacturing. This new approach not only produces directly recyclable linear thermoplastic polymers but also enables the light-based printing of polymers soluble in their own monomer. It was previously demonstrated by Chazot et al. that photo-defined layers of polyacrylonitrile (PAN) can be formed at a liquid-liquid interface; this technique was named interfacial photopolymerization (IPP). In this thesis, which focuses on multilayer 3D printing (3D-IPP), the resolution and stability of layers formed by IPP are improved using a light-absorbing dye while incorporating a water-soluble polyethylene glycol binder to improve yield, printing speed, and mechanical properties. Joint initiation using commercial water-soluble photoinitiators V-50 and LAP, along with the addition of HCL and CaCl2, further enhances printing performance by producing dense layers and reducing voids. Post-processing techniques are devised to preserve part geometry after printing, including controlled air drying, thermal post-processing with PEG infiltration, and the inclusion of compatible polymeric binders in the printing composition to minimize cracking and shrinkage. Additionally, hardware is developed to integrate the IPP process into a commercial projector-based 3D printer, demonstrating compatibility of the proposed chemistry with off-the-shelf hardware. The capability to digitally manufacture high resolution 3D structures with IPP is demonstrated and the physical properties of the resulting composite polymer are characterized. While 3D-IPP cannot yet directly rival conventional manufacturing methods, the benign aqueous chemistry as well as recyclability and circularity of produced parts offers a promising path towards sustainable and resource-efficient AM as the technology matures."],"dc:description.degree":["S.M."],"dc:identifier.uri":["https://hdl.handle.net/1721.1/155850"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)","Copyright retained by author(s)"],"dc:rights.uri":["https://creativecommons.org/licenses/by-sa/4.0/"],"dc:title":["Method for Photopolymerization 3D Printing of Recyclable Thermoplastic Polymers"],"dc:type":["Thesis"],"thesis:degree_name":["Master","Master of Science in Mechanical Engineering"]},"updated_at":"2026-07-22T22:22:04Z"}