TY - JOUR
T1 - Designing Multicomponent Polymer Colloids for Self-Stratifying Films
AU - Singh, Piyush K.
AU - Pacholski, Michaeleen L.
AU - Gu, Junsi
AU - Go, Yoo Kyung
AU - Singhal, Gaurav
AU - Leal, Cecilia
AU - Braun, Paul V.
AU - Patankar, Kshitish A.
AU - Drumright, Ray
AU - Rogers, Simon A.
AU - Schroeder, Charles M.
N1 - The authors acknowledge the Dow University Partnership Initiative (UPI Program) for financial support. The authors thank Luke Yu from the University of Illinois at Urbana-Champaign for useful insights on modeling. Insightful discussions with Hyeonmin Jeong and Charles Sing (Illinois) and Praveen Agarwal, Paul Mwasame, Sipei Zhang, Sean Tang, and Melinda Einsla (Dow) are gratefully acknowledged. The authors thank Hilda Buss (Dow) for chemical synthesis. This research was carried out in part in the Materials Research Laboratory Central Research Facilities, University of Illinois, where the support of research scientists, particularly, Roddel Remy, Timothy Spila, and Mohammad Amdad Ali, is greatly appreciated. Synchrotron X-ray experiments were conducted at beamline 12-ID-B at the Advanced Photon Source (APS), Argonne National Laboratory. Use of APS was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, under Contract DE-AC02-06CH11357. The SAXS characterization experiments were supported by the National Science Foundation under Grant DMR-1554435.
PY - 2022/9/20
Y1 - 2022/9/20
N2 - Aqueous polymer colloids known as latexes are widely used in coating applications. Multicomponent latexes comprised of two incompatible polymeric species organized into a core-shell particle morphology are a promising system for self-stratifying coatings that spontaneously partition into multiple layers, thereby yielding complex structured coatings requiring only a single application step. Developing new materials for self-stratifying coatings requires a clear understanding of the thermodynamic and kinetic properties governing phase separation and polymeric species transport. In this work, we study phase separation and self-stratification in polymer films based on multicomponent acrylic (shell) and acrylic-silicone (core) latex particles. Our results show that the molecular weight of the shell polymer and heat aging conditions of the film critically determine the underlying transport phenomena, which ultimately controls phase separation in the film. Unentangled shell polymers result in efficient phase separation within hours with heat aging at reasonable temperatures, whereas entangled shell polymers effectively inhibit phase separation even under extensive heat aging conditions over a period of months due to kinetic limitations. Transmission electron microscopy is used to track morphological changes as a function of thermal aging. Interestingly, our results show that the rheological properties of the latex films are highly sensitive to morphology, and linear shear rheology is used to understand morphological changes. Overall, these results highlight the importance of bulk rheology as a simple and effective tool for understanding changes in morphology in multicomponent latex films.
AB - Aqueous polymer colloids known as latexes are widely used in coating applications. Multicomponent latexes comprised of two incompatible polymeric species organized into a core-shell particle morphology are a promising system for self-stratifying coatings that spontaneously partition into multiple layers, thereby yielding complex structured coatings requiring only a single application step. Developing new materials for self-stratifying coatings requires a clear understanding of the thermodynamic and kinetic properties governing phase separation and polymeric species transport. In this work, we study phase separation and self-stratification in polymer films based on multicomponent acrylic (shell) and acrylic-silicone (core) latex particles. Our results show that the molecular weight of the shell polymer and heat aging conditions of the film critically determine the underlying transport phenomena, which ultimately controls phase separation in the film. Unentangled shell polymers result in efficient phase separation within hours with heat aging at reasonable temperatures, whereas entangled shell polymers effectively inhibit phase separation even under extensive heat aging conditions over a period of months due to kinetic limitations. Transmission electron microscopy is used to track morphological changes as a function of thermal aging. Interestingly, our results show that the rheological properties of the latex films are highly sensitive to morphology, and linear shear rheology is used to understand morphological changes. Overall, these results highlight the importance of bulk rheology as a simple and effective tool for understanding changes in morphology in multicomponent latex films.
UR - http://www.scopus.com/inward/record.url?scp=85138085472&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85138085472&partnerID=8YFLogxK
U2 - 10.1021/acs.langmuir.2c00855
DO - 10.1021/acs.langmuir.2c00855
M3 - Article
C2 - 36053575
AN - SCOPUS:85138085472
SN - 0743-7463
VL - 38
SP - 11160
EP - 11170
JO - Langmuir
JF - Langmuir
IS - 37
ER -