Description:

“Near Infrared Driven Polymer Actuators”

Prof. Jennifer Lu
University of California, Merced

Abstract

A material that produces mechanoresponse reliably upon low-energy driven stimuli such as near infrared (NIR) (690 - 900 nm) or heating a few degrees above room temperature has significant technological implications. We are investigating two types of mechanoresponsive systems whose conformational changes can be triggered by low-energy stimuli.
Our lab has revealed a new sub-molecular switch, a dibenzocyclooctadiene (DBCOD) -- a hinge that consists of a flexible eight‐membered ring connecting two rigid phenyl rings. Like proteins, the conformational change can be triggered by a low‐energy stimulus such as NIR photon irradiation or heating a few degrees above room temperature. A polymer system that contains a small amount of DBCODs without any process optimization exhibits an anomalous giant thermal contraction. The thermal contraction value is about 10 times greater than the second best reported system. Therefore, a new class of nano- and molecular-actuators driven by NIR, hitherto unavailable, can be attained. The large geometry change in response to ambient temperature fluctuations can also be exploited for thermal sensing or a power-free autonomous heliotropic material for effective solar energy tracking and thus efficient harvesting. It also paves a pathway to create low-thermal expansion polymers.
Our lab is also creating a dynamic scaffold based on NIR stimuli-responsive polymer composites. Together with a spatial light modulator, spatially and temporally defined mechanical forces potentially can be imposed onto cells for influencing stem cell differentiation. Our lab has demonstrated that human fetal hepatocytes seeded on this new dynamic scaffold change their shapes in response to mechanical force induced by near infrared with no obvious detrimental effect on cell viability. This is the first demonstration of a cell-seeding platform that can impose spatiotemporal mechanical forces onto cells to induce shape changes.

Speaker Background

Jennifer Lu is one of the first three faculty members who established the Materials Science and Engineering program at UC Merced ‐‐ California’s newest research university. Prior to joining UC Merced, she acquired ten years industry experience at IBM and Agilent Technologies. She holds over 20 patents related to device fabrication. Her lab has consistently published findings in high impact factor journals. She was a recipient of the DARPA Young Investigator award, and an invited participant in the Frontiers of Science and Engineering workshop co-sponsored by NAE, NAS, and the Brazilian Academy of Sciences. She is current serving as the Director of Merced Nanomaterials Center for Energy and Sensing (MACES) sponsored by NASA.

Date:

Monday, December 12, 2016

Location:

Michael’s at Shoreline
2960 N Shoreline Blvd
Mountain View, CA

Map

Timing:

6 PM social hour
7 PM dinner
8 PM lecture

Cost:

	Employed/postdoc	Student/unemployed/retired
Early Registration	$30	$15
Registration	$35	$20
Walk-in (not guaranteed)	$40	$25

Lecture-only is free.

 

Payment:

We accept cash or checks at the door, or online payment via credit card. No-shows are responsible for full payment of registration fee.

Registration:

Please register below or contact:

Dave Robinson
email: drobins@sandia.gov
phone: 925-294-6613

Deadline for registration:

11:59PM, Monday, December 5 for early registration discount.
5:00PM, Sunday, December 11 for regular registration.

Dinner Selection:

Seafood - Broiled Salmon with lemon beurre blanc
Chicken - Breast of Chicken, Portobello
Vegetarian - Vegetable Napoleon

You should receive confirmation of your registration; if not, please contact us again.