Theoretical and experimental study of dissolution of inhomogeneities formed during spinodal decomposition in polymer mixtures

Akcasu, A. Ziya; Bahar, İvet; Erman, Burak; Feng, Yakai; Han, Charles C.

doi:10.1063/1.463737

Cited by 30 publications

(33 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It requires one to adjust the starting time for the SD process from 0 to ta' Similar idea has been used in the reverse quench case. 42 In Fig. 11(b), we compare measured S(q,ta;T f) with the structure factor constructed in the same way as above but with t replaced by t-7.98 (min) and S(q,ta=O;T f) equated to S(q,O;T f) ' It is clearly seen that the calculated lines can predict S(q,ta;T f) data well and the peak shift in the very early time of SD.…”

Section: Alternative Data Analysis With Cahn-hilliard-cook Theorymentioning

confidence: 99%

Time-resolved small-angle neutron scattering study of spinodal decomposition in deuterated and protonated polybutadiene blends. I. Effect of initial thermal fluctuations

Jinnai

Hasegawa

Hashimoto

et al. 1993

The Journal of Chemical Physics

View full text Add to dashboard Cite

Articles you may be interested inSmall-angle neutron scattering studies of polybutadiene/polystyrene blends as a function of pressure and microstructure: Comparison of experiment and theory Effect of the Onsager coefficient and internal relaxation modes on spinodal decomposition in the high molecular isotopic blend polystyrene/deuteropolystyrene studied with small angle neutron scattering Smallangle neutron scattering by partially deuterated polymers and their blends J. Chem. Phys. 100, 3905 (1994); 10.1063/1.466325 Timeresolved smallangle neutron scattering study of spinodal decomposition in deuterated and protonated polybutadiene blends. II. Qdependence of Onsager kinetic coefficient J. Chem. Phys. 99, 8154 (1993); 10.1063/1.465642 Timeresolved smallangle neutron scattering study of later stage spinodal decomposition of a polymer blend AIP Conf.Time-resolved small-angle neutron scattering (SANS) experiments have been performed on the self-assembling process of a binary mixture of deuterated polybutadiene and protonated polybutadiene at the critical composition. This mixture has an upper critical solution temperature type of phase diagram with the spinodal temperature at 99.2 ·C. Specimens held in the single-phase state at an initial temperature (T;) were quenched to a point inside the spinodal phase boundary at a final temperature (T f) to induce phase separation via spinodal decomposition (SD). In order to examine the effect that thermal concentration fluctuations have on SD, three different initial temperatures, T;= 102.3 ·C, 123.9 ·C, and 171.6 ·C, were chosen while T f was fixed at -7.5°C. The time-dependent SANS structure factor, S(q,t;T f)' showed clear scattering peaks corresponding to the early and intermediate stages of SD. The time changes in the wave number qm(t;T f) and the intensity Sm(t;T f) at the peak of S(q,t;T f) followed different paths depending on the initial temperature. This fact evidences a definite effect of thermal concentration fluctuations on SD (Le., a significant "memory" effect). A critical test of the linearized Cahn-Hilliard-Cook theory led to the conclusion that this theory can describe satisfactorily the early stage SD in the deep-quench region.

show abstract

Section: Alternative Data Analysis With Cahn-hilliard-cook Theorymentioning

confidence: 99%

Time-resolved small-angle neutron scattering study of spinodal decomposition in deuterated and protonated polybutadiene blends. I. Effect of initial thermal fluctuations

Jinnai

Hasegawa

Hashimoto

et al. 1993

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…PVME. 15 Using time-resolved light scattering, they showed that the kinetics of coarsening and This phase separation interpretation also implies that the morphology should change for off-critical dissolution processes are different. This is because growth occurring during the phase-separacompositions.…”

Section: Introductionmentioning

confidence: 98%

Formation and dissolution of phase-separated structures in ultrathin blend films

Ermi

Karim

Douglas

1998

J. Polym. Sci. B Polym. Phys.

View full text Add to dashboard Cite

“…The coefficient of the gradient term, which originates from the random phase approximation, is given by: [25] kðfÞ ¼ 1 36…”

Section: Model and Methodologymentioning

confidence: 99%

“…As for an incompressible polymeric blend, we take the Flory‐Huggins expression for the free energy of mixing where χ is the Flory‐Huggins interaction parameter which characterizes the strength of interaction between the species A and B and favors phase separation when it is positive. The coefficient of the gradient term, which originates from the random phase approximation, is given by:25 where $\sigma _{\rm A} (\sigma _{\rm B} )$ is the monomer size (Kuhn length) of species A(B), which is assumed to be equal in this paper.…”

Section: Model and Methodologymentioning

confidence: 99%

Pattern Evolution Induced by Periodic Temperature Modulation in a Binary Polymeric Mixture

Sun

Song

2006

Macro Theory & Simulations

View full text Add to dashboard Cite

Summary: The process of periodic phase separation is numerically studied based on Cahn‐Hilliard‐Cook theory for a binary polymer blend. The model system is quenched blow and above the critical point alternatively. And hierarchic morphologies consisting of large and small domains are observed. As the periodic phase separation proceeds, small domains are created and destroyed periodically, whereas large domains keep growing. Within the first half of each period, the behavior of small domains is similar to the two‐step phase separation. And the quench to one‐phase region during the second half period not only decreases the peak intensity of structure function for large domains, but also eliminates the high‐wave number peak corresponding to small domains. The average order parameter under oscillatory quenches exhibits a periodic behavior. The minimum of average order parameter in each period approaches to its equilibrium value monotonously and the maximum value increase in the early time regime and decrease in the late time regime. The magnitude of oscillation has considerable effects on the evolution of hierarchic structures. Small magnitude of oscillation hinders the formation of hierarchic morphologies. Moreover, large magnitude of oscillation slows down the coarsening of large domains in the early stage of periodic phase separation and accelerates the growth of large domains in the late time regime. In addition, no scaling invariance could be observed for the net growth of large domains.

show abstract

Theoretical and experimental study of dissolution of inhomogeneities formed during spinodal decomposition in polymer mixtures

Cited by 30 publications

References 28 publications

Time-resolved small-angle neutron scattering study of spinodal decomposition in deuterated and protonated polybutadiene blends. I. Effect of initial thermal fluctuations

Time-resolved small-angle neutron scattering study of spinodal decomposition in deuterated and protonated polybutadiene blends. I. Effect of initial thermal fluctuations

Formation and dissolution of phase-separated structures in ultrathin blend films

Pattern Evolution Induced by Periodic Temperature Modulation in a Binary Polymeric Mixture

Contact Info

Product

Resources

About