Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Robust Polymer Microfluidic Device Fabrication via Contact Liquid Photolitographic Polymerization (CLiPP)
Dept. of Chem. and Biol. Engineering, ECCH 111, University of Colorado.
Dept. of Chem. and Biol. Engineering, ECCH 111, University of Colorado.ORCID iD: 0000-0002-0441-6893
Dept. of Chem. and Biol. Engineering, ECCH 111, University of Colorado.
Dept. of Chem. and Biol. Engineering, ECCH 111, University of Colorado.
Show others and affiliations
2004 (English)In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 4, no 6, 658-662 p.Article in journal (Refereed) Published
Abstract [en]

Microfluidic devices are commonly fabricated in silicon or glass using micromachining technology or elastomers using soft lithography methods; however, invariable bulk material properties, limited surface modification methods and difficulty in fabricating high aspect ratio devices prevent these materials from being utilized in numerous applications and/or lead to high fabrication costs. Contact Liquid Photolithographic Polymerization (CLiPP) was developed as an alternative microfabrication approach that uniquely exploits living radical photopolymerization chemistry to facilitate surface modification of device components, fabrication of high aspect ratio structures from many different materials with numerous covalently-adhered layers and facile construction of three-dimensional devices. This contribution describes CLiPP and demonstrates unique advantages of this new technology for microfabrication of polymeric microdevices. Specifically, the procedure for fabricating devices with CLiPP is presented, the living radical photopolymerization chemistry which enables this technology is described, and examples of devices made using CLiPP are shown.

Place, publisher, year, edition, pages
2004. Vol. 4, no 6, 658-662 p.
Keyword [en]
HIGH-ASPECT-RATIO, ON-A-CHIP, SOFT LITHOGRAPHY, 3-DIMENSIONAL MICROFABRICATION, PHOTOPOLYMERIZATION, SYSTEMS, INIFERTER, MEMS, STEREOLITHOGRAPHY, MONOLITHS
National Category
Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-8068DOI: 10.1039/b405985aISI: 000225382800022OAI: oai:DiVA.org:kth-8068DiVA: diva2:13290
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2010-10-19Bibliographically approved
In thesis
1. Fabrication of polymeric microfluidic devices via photocurable liquid monomers
Open this publication in new window or tab >>Fabrication of polymeric microfluidic devices via photocurable liquid monomers
2005 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Microfluidic devices have long been considered an ideal tool for rapid and inexpensive chemical analysis and reactions in areas ranging from point-of-care health to national security applications. However, fabricating microfluidic devices is time consuming, difficult and above all expensive. In commercial applications many thousand units need to be sold before the development costs are recovered. The problem is compounded since most microfluidic devices do not have generalized architectures which means that each end use requires a specialized design. The microfluidics marketplace can therefore be seen as being composed of 1000’s of niche markets.

To address development costs, there is clearly a need for a versatile technology that can be used for many different applications and that enables rapid testing and optimization of new designs. This work describes such a technology: Contact Liquid Photolithographic Polymerization (CLiPP).

The thesis consists of two parts: polymerization kinetics and the fabrication of polymeric microfluidic devices via CLiPP.

The photopolymerization kinetics is evaluated for a number of monomer types, and the results are used to assess their suitability in the CLiPP process. Vinyl ether/maleate photoinitiated copolymerization is examined in detail. It is shown that the polymerization kinetics is dramatically influenced by the availability of easily abstractable hydrogens The presence of α-hydrogens adjacent to the vinyl ether functional group reduces the polymerization rate and the dependence of the polymerization rate as a function of initiation rate. Also, photoinitiated acrylate and methacrylate polymerization kinetics are presented. The kinetics results in these three monomer types are used to explain the different patterning properties of the monomer functionalities used in the CLiPP process, in which acrylates show enhanced patterning properties compared to methacrylates. The polymerization kinetics is studied with traditional tools and methods: photo Differential Scanning Calorimetry (photo-DSC), photo Fourier Transform Real Time Infrared Spectroscopy (photo-RTIR), and photo Real Time Electron Paramagnetic Spectroscopy (ESR).

The microfluidic fabrication is performed via both in-house fabricated and commercially available CLiPP-specific hardware. The patterning qualities of the structures are evaluated via Scanning Electron Microscopy (SEM) and Optical Microscopy. The finished devices are used in their intended environment and evaluated in suitable manners to assess their utility.

In this thesis, the development and design of specialized CLiPP fabrication machines, fabrication techniques and resulting microfluidic device features are presented anddiscussed. It is shown that the CLiPP scheme enables features such as 3 dimensional (3D) capabilities for minimized device footprints, a very large number of polymeric materials for optimized device components as well as facile integration of prefabricated components. Also, covalent layer adhesion and permanent surface modifications via living radical processes are demonstrated. These capabilities are exemplified in a number of examples that range from a 3D fluidic channel maze with separated fluidic streams and a device with independently moveable parts to a device constructed from multiple polymeric materials and devices with permanently modified surfaces, Also, batch processing capabilities are shown through fabrication of 400 identical undercut microstructures.

Rapid and inexpensive design evaluations, multiple materials capabilities and the ability to seamlessly incorporate prefabricated microstructures of the CLiPP process strongly encourages continued method development. The future work that remains to be addressed is divided into two parts. First, to enable novel research devices, new polymer materials with enhanced mechanical and surface properties must be developed. Also, integration of prefabricated microstructures such as sensors and actuators has to be incorporated in a reproducible and rational manner. Secondly, to enable device mass fabrication, new automated equipment is to be developed in order to utilize the full batch processing potential of CLiPP.

Place, publisher, year, edition, pages
Stockholm: KTH, 2005. viii, 89 p.
Series
Trita-FPT-Report, ISSN 1652-2443 ; 2005:26
Keyword
Photopolymerization, radical photopolymerization, polymerization kinetics, photoinitiation, vinyl ether, maleate, vinyloxy
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-466 (URN)91-7178-183-8 (ISBN)
Public defence
2005-11-11, Sal M1, Brinellvägen 64, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20101019Available from: 2005-10-26 Created: 2005-10-26 Last updated: 2010-10-19Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Authority records BETA

Haraldsson, Klas Tommy

Search in DiVA

By author/editor
Haraldsson, Klas Tommy
In the same journal
Lab on a Chip
Polymer Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 183 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf