Isothermal physical aging of thin PMMA films near the glass transition temperature

J.-E. Nam; J.-K. Lee; C.-S. Oh

doi:10.1117/12.840160

20 October 2009 Isothermal physical aging of thin PMMA films near the glass transition temperature

J.-E. Nam, J.-K. Lee, C.-S. Oh

Proceedings Volume 7493, Second International Conference on Smart Materials and Nanotechnology in Engineering; 749365 (2009) https://doi.org/10.1117/12.840160
Event: Second International Conference on Smart Materials and Nanotechnology in Engineering, 2009, Weihai, China

Abstract

The isothermal physical aging and the glass transition temperature (T_g) in PMMA thin films were investigated by means of differential scanning calorimetry (DSC). Freestanding thin film was obtained by spin coating onto a silicon wafer substrate and then releasing the coated film using a water floating technique for different molecular weights (MW = 120,000, 350,000, 996,000 g/mole) and film thicknesses (40~667 nm). The thin films were stacked in a DSC pan and isothermally aged for different aging times (t_a = 1 and 12 h) and aging temperatures (T_a =105, 110 and 115 oC) below but near T_g. Enthalpy relaxation (▵H_Relax) due to the isothermal physical aging vs. ▵T_a (T_g - T_a, driving force of aging) data showed that the enthalpy value increased with increasing ▵T_a, reached maximum, and then decreased as ▵T_a increases further. As film thickness decreases, ▵H_Relax was rapidly reduced for samples below ~100 nm of film thickness near T_g (e.g., T_a =110 and 115 °C), indicating the suppression of physical aging. About 7~10 oC depression in T_g was observed for thinner films (~40 nm), compared to thicker films (~660 nm) in this study.

Citation Download Citation

J.-E. Nam, J.-K. Lee, and C.-S. Oh "Isothermal physical aging of thin PMMA films near the glass transition temperature", Proc. SPIE 7493, Second International Conference on Smart Materials and Nanotechnology in Engineering, 749365 (20 October 2009); https://doi.org/10.1117/12.840160

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available