Thermally Induced Phase Separation Behavior of Compatible Polymer Mixtures

Nishi, Toshio; Wang, T. T.; Kwei, T. K.

doi:10.1021/ma60044a025

Cited by 370 publications

(200 citation statements)

References 1 publication

(1 reference statement)

Supporting

Mentioning

191

Contrasting

Order By: Relevance

“…During the past years, a large number of studies focused on the miscibility and phase separation in polymer blends, from both theoretical and experimental viewpoints [1][2][3][4][5][6]. For polymer mixtures, controlling components compatibility has always seemed to be a very important factor in polymer industry.…”

Section: Introductionmentioning

confidence: 99%

Interfacial adhesion of nanoparticles in polymer blends by intrinsic fluorescence spectra

Yang¹,

He²,

Zhang³

et al. 2011

Express Polym. Lett.

View full text Add to dashboard Cite

Abstract.Intrinsic fluorescence was applied to quantitatively describe the interfacial adhesion of nanoparticles in polystyrene/poly(vinyl methyl ether) (PS/PVME) blends. Due to the aggregation of aromatic rings on PS chains, the temperature dependence of excimer fluorescence intensity (I 324 ) showed the high sensitivity to the phase separation process. Consistent with Ginzburg thermodynamic model, it was found that the addition of spherical hydrophilic nanoparticles shifted the phase separation temperature to higher temperatures due to the aggregation of silica into PVME chains leading to the free energy reduction and slowing down the phase separation dynamics. A certain composition of polymer blend, i.e. 2/8, was focused on to shed light on the dynamic of spinodal decomposition (SD) phase separation by using decomposition reaction model. It was shown that the addition of nanoparticles to polymer blends resulted in the deviation of linear relationship between the initial SD phase separation rate (R p0 ) and thermodynamic driving force (!f SD ). Besides, for PS/PVME (2/8) with 2 vol% silica nanoparticles, the apparent activation energy of phase separation (E a ) was 196.61 kJ/mol, which was higher than that of neat PS/PVME (2/8) blend (E a = 173.68 kJ/mol), which strongly confirmed the interfacial adhesion effect of silica nanoparticles as compatibilizers.

show abstract

Section: Introductionmentioning

confidence: 99%

Interfacial adhesion of nanoparticles in polymer blends by intrinsic fluorescence spectra

Yang¹,

He²,

Zhang³

et al. 2011

Express Polym. Lett.

View full text Add to dashboard Cite

show abstract

“…18 -26 For polymer solutions and polymer blends, however, only a few experimental studies on SD have been made, 27 -31 while some studies have focused on coarsening processes. 32 • 33 For a liquid mixture of polystyrene and poly(vinyl methyl ether), for example, Nishi et al 30 observed by pulsed NMR technique the change in composition with time during spinodal decomposition and evaluated the kinetic parameters describing the spinodal decomposition by use of the Cahn theory. In this series of studies, our aim has been to obtain a understanding of the mechanisms of phase separation, at both the early and late stages, of polymer solutions and polymer blends.…”

mentioning

confidence: 99%

Phase Separation Process in Polymer Systems. I. Light Scattering Studies on a Polystyrene and Poly(methylphenylsiloxane) Mixture

Nojima

Tsutsumi

Nose

1982

Polym J

View full text Add to dashboard Cite

ABSTRACT:Early stages of phase separation in liquid mixtures of polystyrene (PS) and poly(methylphenylsiloxane) were studied by light scattering. Measurements were made at four concentrations less than 60 wt% PS and at several temperatures in the two-phase region. The time (t) dependence of maximum intensity of scattered light /m and the corresponding wave number km did not obey the Cahn theory but could be represented by power-laws: Imoc. A phase separation of polymer systems upon quenching starts from a homogeneous state and proceeds through a series of heterogeneous states, as is the case with the liquid-gas phase transition in one-component systems or with liquid-liquid or solid-solid phase separation in two-component systems of small molecules. The process can be divided into two main stages, early and late, depending on the degree of time evolution. 1 At the early stages, there occur dominant concentration fluctuations in a homogeneous phase (mother phase or matrix), and these lead to the birth of new phases (daughter phases). At the late stages, called the coarsening process, 2 the size and number of daughter phases change accompanying neither nucleation of new phases nor variation in composition, and the gradual aggregation of daughter phases occurs by what is called the coalescence 1 or Ostwald Ripening mechanism.3.4 Finally, the entire system settles down to a macroscopic two-phase state.The early stage proceeds either by spinodal decomposition (SD) or by nucleation and growth. 5 The former takes place spontaneously without energy barriers when the system is brought into an unstable region, since any concentration fluctuation over a certain range of wave lengths reduces the free energy of the unstable system. The latter starts when the system enters into a metastable region, in which the system is unstable only for seldom-occurring sufficiently large concentration fluctuations. Thus, in this, there is an energy barrier for the nucleation of a new phase, but once it is formed, the new phase grows rapidly by diffusion.Spinodal decomposition was first formulated by Hillert 6 and Cahn (Cahn theory) 7 based on a linear mean field theory for concentration fluctuations. 8 In the framework of a mean field approximation, the Cahn theory was modified by Cook, 9 Langer, 10 -12 and Abraham 13 • 14 to take non-linear effects into account, and extended to polymer blends by de Gennes with the tube modelY On the other hand, Binder 16 and Kawasaki and Ohta 17 have developed new approaches to spinodal decomposition by using modern theories of phase transition.Recently, many experimental studies have been 225

show abstract

“…In some cases, spinodal decomposition may result if the metastable region is rapidly crossed such that nucleation of phase separation does not occur. In addition to the observations by McMaster, another early study of spinodal decomposition was reported by Nishi et al [60].…”

Section: Phase Separation: Spinodal Decomposition Versus Nucleation Amentioning

confidence: 84%

Historical Perspective of Advances in the Science and Technology of Polymer Blends

Robeson

2014

Polymers

View full text Add to dashboard Cite

This paper will review the important developments in the field of polymer blends. The subject of polymer blends has been one of the most prolific areas in polymer science and technology in the past five decades judging from publications and patents on the subject. Although a continuing important subject, the peak intensity occurred in the 1970s and 1980s. The author has been active in this area for five decades and this paper is a recollection of some of the important milestones/breakthroughs in the field. The discussion will cover the development of the theory relevant to polymer blends, experimental methods, approaches to achieve compatibility in immiscible/incompatible blends, the nature of phase separation and commercial activity.

show abstract

Thermally Induced Phase Separation Behavior of Compatible Polymer Mixtures

Cited by 370 publications

References 1 publication

Interfacial adhesion of nanoparticles in polymer blends by intrinsic fluorescence spectra

Interfacial adhesion of nanoparticles in polymer blends by intrinsic fluorescence spectra

Phase Separation Process in Polymer Systems. I. Light Scattering Studies on a Polystyrene and Poly(methylphenylsiloxane) Mixture

Historical Perspective of Advances in the Science and Technology of Polymer Blends

Contact Info

Product

Resources

About