About

Michael Bortner is a professor in the Department of Chemical Engineering at Virginia Tech. He earned his Ph.D. from Virginia Tech in 2003, his M.Eng. from Virginia Tech in 2002, and his B.S. from Penn State in 1998. His research interests include polymer nanocomposites, nanostructured materials and surfaces, polymer morphology and structure-property relationships, and surface and interface phenomena in polymers. His applications focus on additive manufacturing, composite processing, smart materials, advanced materials, structural composites, and multifunctional coatings. Dr. Bortner's expertise encompasses nanomaterial dispersion and characterization, manufacturing process development, novel nanocomposite characterization techniques, and transport phenomena at polymer/particle interfaces and in multi-phase systems.

Research topics

• Composite material
• Materials science
• Organic chemistry
• Chemistry
• Chemical engineering
• Mechanical engineering
• Engineering
• Polymer chemistry
• Manufacturing engineering
• Nanotechnology
• Process engineering
• Crystallography
• Thermodynamics
• Aerospace engineering
• Engineering drawing
• Combinatorial chemistry
• Chromatography

Selected publications

• Building tomorrow: Unlocking the potential of additive manufacturing to revolutionize coastal infrastructure

  Integrated Environmental Assessment and Management · 2026-03-28

  articleOpen access

  Natural and engineered waterborne infrastructure are critical resources necessary for coastal protection, economic security, and ecosystem services; however, increasing pressures from natural hazard events are compromising the performance and resilience of these systems. Addressing these challenges requires innovative approaches that enhance infrastructure functionality while expanding social, economic, ecological, and recreational benefits. Additive manufacturing (AM), including 3D printing (3DP), presents a promising pathway to transform the design and implementation of nature-inspired infrastructure. These technologies enable the fabrication of complex, bioinspired structures using natural or sediment-based materials, aligning with Engineering With Nature® (EWN®) principles and U.S. Army Corps of Engineers (USACE) infrastructure priorities. Despite this potential, key knowledge gaps remain that limit the transition from conceptual designs to scalable, field-ready applications. To address these gaps, an inaugural collaborative research workshop was convened at the U.S. Army Engineer Research and Development Center (ERDC). The workshop brought together interdisciplinary experts to evaluate current capabilities and define pathways for advancing nature-inspired 3DP solutions. Discussions were organized across four thematic areas: ecosystem restoration and bio-inspired design, coastal resilience, material and sediment properties, and scaling from benchtop to field implementation. Outcomes from the workshop highlight critical research needs, including material standardization, performance validation, and integration with existing engineering practices. This emerging capability also enables the embedding of habitat features, integration of sensors for monitoring infrastructure performance and environmental or security threats, and incorporation of carbon sequestration strategies directly into engineered systems. In addition, AM/3DP supports the retrofitting of existing gray infrastructure, advancing "greening the gray" approaches that enhance resilience and flood protection for both communities and critical assets. Collectively, these findings identify actionable pathways to develop feasible, scalable solutions that deliver multi-benefit outcomes. This work supports a broader paradigm shift toward integrating nature-based approaches with advanced manufacturing technologies in coastal infrastructure.

  PublisherDOI

• Hydroxypropyl cellulose/thermoplastic polyurethane blend films with reversible optical performance triggered by water

  Carbohydrate Polymers · 2026-02-21

  articleSenior authorCorresponding
  PublisherDOI

• Experimental evidence of sticky rouse behavior in a disulfide-crosslinked vitrimeric thermoplastic

  Chemical Engineering Journal · 2026-05-01

  articleSenior author
  PublisherDOI

• Crystallization–gelation Interplay in Solidification of Carbon Fiber and Graphite Filled Polypropylene: Medium-format Extrusion-based Additive Manufacturing Case Study

  Materials & Design · 2026-03-29

  articleOpen accessSenior author
  PublisherDOI

• Breaking Bad: Deagglomerating TiO ₂ in 3D Printable Polymer Composites for Photocatalysis in Environmental Media

  ACS Applied Materials & Interfaces · 2026-02-16 · 1 citations

  articleOpen accessSenior author

  dispersion and distribution by twin screw extrusion are sufficient to achieve environmentally effective degradation rates if agglomerates are less than approximately 20 μm (an image analysis cutoff) and if these smaller agglomerates remain near the surface of printed structures. When such dispersion states are achieved, additional efforts to break up agglomerates appear nonessential for acceptable photocatalytic performance.

  PublisherDOI

• Additive manufacturing of vitrimers: Interplay between polymer physics and processing approaches

  Chemical Engineering Journal · 2025-10-28 · 2 citations

  articleSenior authorCorresponding
  PublisherDOI

• Realizing semicrystalline polymer physics across disparate processing scales: From desktop extrusion to large-format additive manufacturing

  Progress in Polymer Science · 2025-11-17 · 1 citations

  articleSenior authorCorresponding
  PublisherDOI

• Going against the grain: Porous defects in polymer-zeolite composite extrusion to enhance contaminant adsorption

  Additive manufacturing · 2025-03-29 · 1 citations

  articleSenior authorCorresponding
  PublisherDOI

• Impact of polymer molecular weight blends on the powder bed fusion process and the properties of polypropylene printed parts

  RSC Applied Polymers · 2025-01-01 · 4 citations

  articleOpen access

  Designing and controlling the molecular characteristics of polymeric feedstocks provides a cost-effective strategy to tune the properties of structures formed via the powder bed fusion process.

  PublisherOA PDFDOI

• Development of a Miniaturized Capillary Rheometer for High Shear Rate Rheology of Dense Suspensions

  Advanced Materials Technologies · 2025-06-13 · 2 citations

  articleOpen accessSenior authorCorresponding

  Abstract Traditional capillary rheometers are effective for determining high rate steady shear viscosity of non‐Newtonian fluids at processing relevant conditions. However, they require substantial capital investment and dozens of grams of material, presenting challenges working with limited sample quantities or hazardous materials. Additional challenges with dense suspensions include particle bridging at the transducer orifice or die and large dead zones of aggregation resulting from the sharp entry angles from piston to die. A downscaled, “disposable” capillary rheometer termed the “miniaturized capillary rheometer” is introduced to address these challenges. This device can be created in a typical lab space at low cost and requires only single grams of sample. To validate the miniaturized capillary rheometer measurements, three different dense suspensions with different particle size and geometry (60 vol% glass microbubbles, 7 vol% fumed silica, and 20 vol% calcium carbonate) are evaluated over a range of shear rates spanning 63–1000 s −1 and compared to full‐scale capillary rheometry. Apparent viscosity profiles generally agree between both methods, with improved agreement in true viscosity once Bagley and Weissenberg–Rabinowitsch corrections are applied. These findings substantiate this miniaturized approach for measuring viscosity of dense suspensions, enabling studies with small material quantities at a fraction of the cost.

  PublisherOA PDFDOI

Frequent coauthors

• Arit Das

  Virginia Tech

  25 shared

• Christopher B. Williams

  19 shared

• Donald G. Baird

  Virginia Tech

  12 shared

• Jacob J. Fallon

  Virginia Tech

  11 shared

• John P. Reynolds

  9 shared

• Alan R. Kennedy

  U.S. Army Engineer Research and Development Center

  9 shared

• Eric L. Gilmer

  Virginia Tech

  8 shared

• E. Johan Foster

  University of British Columbia

  8 shared