Synthetic vascular materials via a vaporization of sacrificial component (VaSC) approach

The introduction of microchannels into traditional composites has numerous applications ranging from self-healing to autonomous cooling materials. However, current approaches for microvascularization are hindered by scalability and lack of compatibility with the composite manufacturing proceess. Herein, we present the development of a new procedure for incorporating microchannels into composites that overcome these limitations. Namely, the vaporization of sacrificial component (VaSC). The chosen sacrificial material, poly(lactic acid) (PLA), can be easily incorporated into composites and undergoes a solid-to-gas transition at ca. 280 oC, which allows for the extraction of the gaseous product from the composite leaving hollow spaces in the matrix. The fabrication of a microvascular composite by this method necessitated the development of PLA sacrificial fibers, and three distinct production techniques for producing the desired PLA fibers were explored (chemical modification of commercial PLA fibers, homespun PLA fibers, and micro-structuring of a PLA film). The dissertation also discusses the coated sacrificial fibers (CSFs) as a building block for biomimetic vascular structures. In addition, the fabrication of a microporous battery separator via a similar VaSC approach was developed. In order to improve the safety of automobile battery systems, we sought to apply produce a thermally stable battery separator that prevents cell shortage by establishing a high-temperature fabrication route. A solution containing PLA and polyimide (PI) was cast into form a biphasic film; thermal removal of the PLA phase left a microporous PI film. Experimental evidence showed that the microporous PI film that was fabricated using the PLA sacrificial component had superior thermal properties and could potentially replace current commercial separators.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Materials Science & Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Dong, Hefei

Contributors dc:contributor

• Moore, Jeffrey S.
• White, Scott R.
• Sottos, Nancy R.
• Braun, Paul V.
• Cheng, Jianjun

• self-healing materials
• poly(lactic acid) (PLA)
• hot pressing
• vaporization of sacrificial component (VaSC)
• microvascular composites
• fiber spinning
• vascular materials

Statement dc:rights

• Cpoyright 2013 Hefei Dong

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/46825

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/46825