NORTHWESTERN UNIVERSITY
The mechanical properties of polymers in confined domains are examined from a novel combination of nanoscale indentation experiments and theory. The work will be directly applied to thin polymer films and then extended to model polymer nanocomposites. These results will be the first of their kind to determine the nanoscale, local mechanical properties of polymers, providing new insight to help understand the physics of polymer chain motion and response near interfaces. The mechanics simulation and modeling will extend methods developed from contact mechanics theory to soft materials with viscoelastic properties and strong surface-driven property gradients and will overcome current limitations.
The research is a creative, interdisciplinary endeavor, directly training graduate students, undergraduates and postdocs in research methods, experimental design, modeling, and nanotechnology, as applied to polymer systems and soft materials. The results will help understand fundamental issues in design of polymer products in the microelectronics, medical and structural fields ? these applications increasingly hinge upon polymers in small domains and at interfaces, demanding a deep understanding of local polymer properties to intelligently tailor small scale architectures. The work also has far-reaching impacts beyond the study of polymers in the development of a rigorous method to probe properties of materials via nanoindentation in cases of small sample sizes, where current size effects prohibit results. The analysis approach developed here can be extended to biological samples, with many of the same features and concerns, where small scale mechanics are increasingly discovered to play critical roles in biological properties and function.
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| AWARD OVERVIEW |
| Award Number |
0928050 |
Funding Agency |
National Science Foundation |
| Total Award Amount |
$380,000 |
Project Location - City |
Evanston |
| Award Date |
06/03/2009 |
Project Location - State |
IL |
| Project Status |
More than 50% Completed |
Project Location - Zip |
60208-1110
|
| Jobs Reported |
1.09 |
Congressional District |
09 |
| Project Location - Country |
US |
|
|
Recipient Information
(Grants)
| Recipient Information (Grants) |
|
Recipient Name
|
NORTHWESTERN UNIVERSITY |
| Recipient DUNS Number |
160079455
|
| Recipient Address |
633 CLARK ST EVANSTON |
| Recipient City |
EVANSTON |
| Recipient State |
Illinois |
| Recipient Zip |
60208-0001 |
| Recipient Congressional District |
09 |
| Recipient Country |
USA |
Required to Report Top 5
Highly Compensated Officials |
No |
Projects and Jobs Information
| Projects and Jobs Information |
| Project Title |
New Approach to Nanoindentation Experiments and Modeling: Toward Fundamental Understanding of Thin Polymer Films and Polymer Nano Composites |
| Project Status |
More than 50% Completed |
| Final Project Report Submitted |
No |
| Project Activities Description |
Engineering & Technology |
| Quarterly Activities/Project Description |
In this period of time, the investigation of interphase between polymer and inorganic materials continued on nanocomposites of carbon nanotube (CNT) with Polystyrene (PS). A new method has been explored to enable the study of interphase around a single nanotube in real nanocomposites. The samples were prepared in three ways: 1. CNTs were blended with PS directly; 2. CNTs, activator and PS were mixed at the same time; 3. CNTs were fully blended with activators first then embedded in PS. All the samples came in with various weight percentages. In order to use AFM, a smooth cross-section on nanocomposites is required. First, ion milling was employed. However after examining by SEM and AFM, it was observed that all the nanotubes on milled surface were destroyed by ion beams, except the ones inside big clusters, which cannot be picked and tested by AFM tip. Then, mechanical polishing was performed, but the surface roughness was not able to be reduced to satisfy the requirement of AFM tests. Finally, microtoming was performed, which uses an ultra-sharp diamond blade to quickly cut out a thin film of nanocomposites from bulk samples. It was then shown that microtoming can keep nanotubes intact and surface roughness acceptable at the same time. On the microtomed nanocomposites thin films, many CNT clusters can be found. Comparing to non-activated samples, the fully activated ones with same weight percentage exhibit much less clusters, which indicates better CNT dispersion, and better chances to find a single nanotubes surrounded by interphase. So the AFM tests were mainly focused on fully activated samples. On the perimeter of CNT clusters, several single CNTs were successfully located, and the interphases around them were measured. And the AFM surface potential mapping is also explored to reveal the CNT networks beneath surface. Additional work needs to be done to correlate surface potential mapping and modulus mapping. |
| Jobs Created |
1.09 |
| Description of Jobs Created |
American Recovery and Reinvestment Act funds have significantly aided the research mission of Northwestern University by providing salary and wage compensation for individuals directly involved in ARRA-funded projects, both at Northwestern and at consortium institutions, as well as at the vendor organizations who provide goods and services in support of that mission. Northwestern has employed a standard methodology for determining jobs created or retained, based on revised guidance presented by OMB on 12-18-09 (ref. M-10-08). Jobs are reported in aggregate for the grant, comprised of calculated figures for hourly and salaried employees at Northwestern plus the reported jobs created or retained by subrecipients. The number of Northwestern hourly employees will be calculated as the number of hours charged to the grant during the quarter divided by the standard hours in a full-time schedule for the quarter. The number of Northwestern salaried employees will be calculated based on the salaries charged to the ARRA fund during the quarter. Following is a list of descriptions for jobs created or retained, in whole or in part, by this ARRA funded project:Laboratory Aide,Research Assistant. |
Purchaser Information
(Grants)
| Purchaser Information |
| Contracting Office ID |
Not Reported |
| Contracting Office Name |
Not Available |
| Contracting Office Region |
Not Available |
| TAS Major Program |
49-0101 |
| Award Information |
| Award Date |
06/03/2009 |
| Award Number |
0928050 |
| Order Number |
|
| Award Type |
Grants |
| Funding Agency ID |
49 |
| Funding Agency Name |
National Science Foundation |
| Funding Office Name |
Not Available |
| Awarding Agency ID |
49 |
| Awarding Agency Name |
National Science Foundation |
| Amount of Award |
$380,000 |
| Funds Invoiced/Received |
$336,622 |
| Expenditure Amount |
$355,757 |
| Infrastructure Expenditure Amount |
$0 |
| Infrastructure Purpose and Rationale |
Not Reported |
| Infrastructure Point of Contact Name |
Not Reported |
| Infrastructure Point of Contact Email |
Not Reported |
| Infrastructure Point of Contact Phone |
Not Reported |
| Infrastructure Point of Contact Address |
Not Reported |
| Infrastructure Point of Contact City |
Not Reported |
| Infrastructure Point of Contact State |
Not Reported |
| Infrastructure Point of Contact Zip |
Not Reported |
Product or Service Information
(Grants)
| Product or Service Information |
| Primary Activity Code |
U03 |
| Activity Description |
Engineering & Technology |
| Sub-Awards Information |
| Sub-awards to Organizations |
0 |
| Sub-award Amounts to Organizations |
$0 |
| Sub-Awards to Individuals |
0 |
| Sub-Award Amounts to Individuals |
$0 |
| Number of Sub-awards less than $25,000/award |
0 |
| Amount of Sub-awards less than $25,000/award |
$0 |
| Number of payments to vendors greater than $25,000 |
0 |
| Total Amount of payments to vendors greater than $25,000/award |
$0 |
| Number of payments to vendors less than $25,000/award |
13 |
| Total Amount of payments to vendors less than $25,000/award |
$1,818 |
| Location Information |
| Latitude, Longitude |
42º 3' 20",
-87º 40' 28" |
| Congressional District |
09 |
| Address 1 |
633 Clark St |
| Address 2 |
|
| City |
Evanston |
| County |
Cook |
| State |
IL |
| Zip |
60208-1110 |
|
 |