December 1 - 6, 2024
Boston, Massachusetts
Symposium Supporters
2024 MRS Fall Meeting & Exhibit
NM04.08.05

Interaction of CdS QDs with the PS/PMMA Polymer Blend Thin Film and Their Influences on Morphology

When and Where

Dec 5, 2024
3:15pm - 3:30pm
Hynes, Level 1, Room 110

Presenter(s)

Co-Author(s)

Hemant Kumar1,Rabibrata Mukherjee1,Pallab Banerji1

Indian Institute of Technology Kharagpur1

Abstract

Hemant Kumar1,Rabibrata Mukherjee1,Pallab Banerji1

Indian Institute of Technology Kharagpur1
Two polymers that are immiscible when dissolved in a mutual solvent undergo phase separation during spin coating on a non-wettable surface. Rapid evaporation of the solvent creates Marangoni stresses leading to instability between the two polymer interfaces. Phase separated morphology is influenced by several factors such as type of solvent, respective solubility of polymers, relative molecular weight, ratio of the polymers, type of the substrate and also its favored affinity towards the constituents. In this article surface morphology of as cast thin films of PS/PMMA polymer blend of composition 1:1 (ratio of PS & PMMA in solution, v/v) has been modulated by addition of CdS quantum dots. While presence of nano particles in a homo-polymer film makes the film stable against dewetting, in a blend it can also alter film morphology. To understand the influence of quantum dots in polymer blends, the morphology of spin coated PS/PMMA blend films was studied first. Upon addition of QDs, changes in morphology of the polymer blend film was studied with an Atomic Force Microscope. The Quantum dot concentration (CQDs) was varied between 0% to 10%. As the concentration of QDs increases, size of PS domain is found to increase. In contrast, annealing above glass transition of PS/PMMA suppresses the PMMA domains in the particle free film. Blends containing QDs show a similar change in morphology, upon annealing, as QD free films. Photoluminescence (PL) spectra of the QD containing blend is similar to the particle free blend film, revealing that upon addition of QDs in a blend, optical properties remain unaltered. Moreover, the slight narrowing of PL spectra on addition of QDs in the blend has been observed which is attributed to the scattering effect in the blend. RAMAN spectra indicate the presence of particles in the PS as well as PMMA domains.

Keywords

interface | polymer | thin film

Symposium Organizers

Sanghoon Bae, Washington University in Saint Louis
Jeehwan Kim, Massachusetts Institute of Technology
Ho Nyung Lee, Oak Ridge National Laboratory
Nini Pryds, Technical University Denmark

Session Chairs

Chun Ning (Jeanie) Lau
Yun Seog Lee

In this Session