Accession Number:

ADA516059

Title:

STIR: Active Polymer Micro-Constructs

Descriptive Note:

Final rept. 15 Sep 2008-14 Jun 2009

Corporate Author:

MASSACHUSETTS UNIV AMHERST MA OFFICE OF GRANT AND CONTRACT ADMIN

Personal Author(s):

• Kim, Jungwook
• Yoon, Jinhwan
• Hayward, Ryan C.

Report Date:

2009-09-16

Pagination or Media Count:

6.0

Abstract:

We have developed temperature-responsive 3-D actuating hydrogel microstructures based on lithographically-patterned photo-crosslinkable polyN-isopropyl acrylamide copolymers. In one approach, a bilayer gel microstructure is constructed by joining together patterned layers of chemically distinct polymers with differing propensities to swell when placed in water. In a second approach, a single copolymer is used, but the duration of exposure to UV light 365 nm is spatially varied, leading to lateral patterning of the crosslink density of the polymer network, and therefore its degree of swelling. In either case, the swelling of the more expansive elements is constrained by the presence of the less expansive elements, generating swelling stresses within the 2-D patterned hydrogel film, driving deformation into a 3-D microstructure that actuates in response to changes in temperature.

Descriptors:

• *COPOLYMERS
• *HYDROCARBONS
• *ACTUATION
• *DEFORMATION
• *POLYMERS
• *MICROSTRUCTURE
• MONOMERS
• GELS
• CROSSLINKING(CHEMISTRY)
• PHYSICAL PROPERTIES
• CHEMICAL PROPERTIES
• THREE DIMENSIONAL
• DENSITY

Subject Categories:

• Organic Chemistry
• Polymer Chemistry
• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE