Effects of photointensity gradient on directional crystal growth in blends of crystalline polymer and photoreactive monomer undergoing photopolymerization-induced phase transformation

Journal Article · Thu May 07 00:00:00 EDT 2009 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.3126663· OSTI ID:21559712

Rathi, Pankaj; Park, Soo Jeoung; Kyu, Thein ^[1]

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1. Department of Polymer Engineering, University of Akron, Akron, Ohio 44325 (United States)

Effects of light intensity gradient on development of intricate hierarchical morphology of semicrystalline polyethylene oxide (PEO) and photoreactive diacrylate (DA) blends undergoing photopolymerization-induced crystallization have been demonstrated experimentally and theoretically. The melting temperature of PEO was found to decline upon addition of DA monomer. A solid-liquid phase diagram has been established by self-consistently solving the combined phase field free energy of crystal solidification and Flory-Huggins (FH) free energy of liquid-liquid demixing. Dynamic calculations were performed using time-dependent Ginzburg-Landau (model C) equations by incorporating the combined phase field and FH free energy densities coupled with the photopolymerization kinetics. The spatiotemporal development of gradient morphology was computed under various intensity gradient profiles including linear, cylindrical, and Gaussian profiles. The observed seaweed or dense lamellar branching morphology of the PEO/DA blend is strikingly similar to the directionally grown interface structures observed in metals driven by external thermal gradients.

• OSTI ID: 21559712
• Journal Information: Journal of Chemical Physics, Vol. 130, Issue 17; Other Information: DOI: 10.1063/1.3126663; (c) 2009 American Institute of Physics; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ACRYLATES
CRYSTAL GROWTH
CRYSTALLIZATION
CRYSTALS
FREE ENERGY
GINZBURG-LANDAU THEORY
KINETICS
LIQUIDS
MELTING
MELTING POINTS
MONOMERS
MORPHOLOGY
PHASE DIAGRAMS
POLYETHYLENE GLYCOLS
POLYMERIZATION
SOLIDIFICATION
SOLIDS
TIME DEPENDENCE
ALCOHOLS
CARBOXYLIC ACID SALTS
CHEMICAL REACTIONS
DIAGRAMS
ENERGY
FLUIDS
GLYCOLS
HYDROXY COMPOUNDS
INFORMATION
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
POLYMERS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE