Laser Light Scattering Studies of Bulk Polymers in the Glass Transition Regime

Jamieson, A. M.; Simha, Robert; Lee, H.; Tribone, J.

doi:10.1111/j.1749-6632.1981.tb55660.x

Cited by 5 publications

(2 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this section we shall summarize the empirical evidence for several polymers from investigations of the local segmental motions by both dynamic light scattering and dielectric relaxation. In particular, we find the three inequalities (3), (4), and (9) hold simultaneously. We shall collect the experimental data of PPG, PVAc, PEA, and PMA.…”

Section: Experimental Data Establishing a Correlationmentioning

confidence: 78%

“…A larger value of the parameter B is experimentally observed for dynamic light scattering than that for dielectric relaxation, if the same TQ is used in both VFTH representations of rb and rdt. Whence, it follows from inequality (4) that Bb > B^ (9) and the correlation between n and B is found. More importantly, we find the experimental data are in good Data not reported or not tabulated.…”

Section: Introductionmentioning

confidence: 93%

See 1 more Smart Citation

Intercomparisons of dielectric relaxation, dynamic light scattering, and viscoelastic properties of the local segmental motion in amorphous polymers

Ngai¹,

Mashimo²,

Fytas³

1988

Macromolecules

View full text Add to dashboard Cite

Independent of the nature of the probe (e.g., longitudinal compliance by dynamic light scattering, shear compliance by dynamical compliance and modulus or by creep recovery, electric compliance by dielectric relaxation) near and above the glass temperature, the appropriate correlation or relaxation function of the local segmental motion in an amorphous polymer is well described by the Kohlrausch-Williams-Watts function ß |-( / *)1' |. The temperature dependence of the effective time t* is well represented by the Vogel-Fulcher-Tamann-Hesse equation t* = exp|B/(T-T0)j. However, the fractional exponent n and the quantity B, for a fixed T0, can depend on the nature of the probe. Through a compilation of the experimental data of a number of amorphous polymers, we have established an empirical correlation between n and B. Whenever the two quantities n and B are probe dependent in an amorphous polymer, we find the product (1 -n)B remains invariant. An explanation of this empirical relation can be found from an extant prediction of the coupling model of relaxation.

show abstract

Section: Experimental Data Establishing a Correlationmentioning

confidence: 78%

Section: Introductionmentioning

confidence: 93%

Intercomparisons of dielectric relaxation, dynamic light scattering, and viscoelastic properties of the local segmental motion in amorphous polymers

Ngai¹,

Mashimo²,

Fytas³

1988

Macromolecules

View full text Add to dashboard Cite

show abstract

Appendix B: Robert Simha Publications

2010

Polymer Physics

View full text Add to dashboard Cite

Rayleigh‐brillouin spectroscopy of syndiotactic poly(n‐butyl methacrylate) near the glass transition

Patterson

Jue

Stevens

1990

J Polym Sci B Polym Phys

View full text Add to dashboard Cite

We present Rayleigh‐Brillouin light scattering data of highly syndiotactic poly(n‐butyl methacrylate) [PBMA] whose glass transition temperature as measured by DSC is 55°C. The Brillouin peak shifts, Brillouin peak widths, and Landau‐Placzek ratios from −15 to 130°C are reported. The Brillouin peak widths decrease continuously through the glass transition region. This indicates a continual decrease in the strength of processes whose relaxation times are about 10−10 s with decreasing temperature even as the system becomes glassy. The Landau‐Placzek ratio above the glass transition is about 3, indicating the high optical purity of our sample. This low Landau‐Placzek ratio arises from the sample's homogeneous stereochemistry. Some of the anomalous behavior observed around 40–50°C in previous PBMA studies is explained in terms of syndiotactic regions within a largely atactic sample.

show abstract

Laser Light Scattering Studies of Bulk Polymers in the Glass Transition Regime

Cited by 5 publications

References 27 publications

Intercomparisons of dielectric relaxation, dynamic light scattering, and viscoelastic properties of the local segmental motion in amorphous polymers

Intercomparisons of dielectric relaxation, dynamic light scattering, and viscoelastic properties of the local segmental motion in amorphous polymers

Appendix B: Robert Simha Publications

Rayleigh‐brillouin spectroscopy of syndiotactic poly(n‐butyl methacrylate) near the glass transition

Contact Info

Product

Resources

About