Effect of added block copolymer on phase-separation kinetics of a polymer blend. 1. A light-scattering study

Abstract

A light-scattering study has been made to investigate the effect of added styrene-butadiene diblock copolymer on the phase-separation kinetics of blends of low molecular weight polystyrene and polybutadiene. The scattered light intensity was measured at 2 O intervals up to 60' as a function of time from the beginning of phase separation into the late stage of Ostwald ripening. Various corrections, including the one for double scattering, were applied to the observed intensity. The effect of the added block copolymer was to retard the growth of phase-separated domains, as seen from the time evolution of qmw and I,, of the peak in the intensity curve. This can be explained in terms of the reduction in the interfacial tension between the demixed phases, resulting from accumulation of block copolymer there. The time-evolution exponents of qmu and I, , , the invariant Q, and the superposition of scattering intensity curves all show the validity of dynamic scaling in the late ripening stage.

Particulate growth in phase-separated polymer blends

“…The binary blends of PS/PB, PS/PI, and PS/R715 show nearly a 1 3 growth rate, while the blend with 8 wt % diblock (PS/PB/ D730A) has a growth of 0.14. Previously, the addition of a block copolymer to a blend has been shown to decrease the growth rate in blends where Ostwald ripening 25 or coalescence 26,27 was believed to be occurring. Also, the Ising-type model of Kandasamy and Nauman 28 predicts a …”

Synthesis and Characterization of a Diblock Copolymer of Methyl Methacrylate and Vinyl Acetate by Successive Photo-Induced Charge Transfer Polymerization Using Ethanolamine as the Parent Compound

“…[7] This means that this kind of blends is homogeneous and miscible at low temperature and immiscible at high temperature. The effect of the block or graft copolymer as the compatibilizer on the corresponding blend pairs with an upper critical solution temperature (UCST) phase diagram has been widely investigated, including polystyrene-block-polybutadiene (PS-b-PB) [8,9] and polystyreneblock-poly(methyl phenyl siloxane) (PS-b-PMPS) systems. [10] However, the system with LCST phase diagram Communication: A diblock copolymer consisting of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate) (PVAc) with hydroxyl group at one end is prepared by successive charge transfer polymerization (CTP) under UV irradiation at room temperature using ethanolamine and benzophenone as a binary initiation system.…”

Modeling the effect of compatibilizers in the coarsening of ternary polymer blends with core-shell morphology

“…The coarsening of particles in a phase‐separated polymer blend has received much attention in the recent literature 1–9. This is due in part to the importance of particle size with respect to the physical properties of a given blend.…”