Thermal transition behavior

Allcock HR, Mang MN, Dembek AA, et al. Poly[(aryloxy)phosphaz enes] with phenylphenoxy and related bulky side groups, synthesis, thermal transition behavior, and optical properties [J]. Macromolecules, 1989, 22, 4179 190. 

Similarly, the thermal transition behavior of the members of the P(DMA)- fflf-(HPA) copolymer library was investigated using DSC. For all members of this library, single Tg were obtained, which is an indication of a good mixing of the two... 

A similar evaluation was made for the other series of CA-g-PHAs to establish a general relationship between their molecular architecture and thermal transition behavior [24]. Of particular interest is the finding that the composition dependence of the Tg of the cellulosic graft copolymers was represented well in terms of a formulation based on a comb-like polymer model [29], when CAs of acetyl DS 2 were employed as a trunk polymer. 

For thermal transition behavior of polymers, such as glass transition and melt transition, refer to F. W. Billimeyer, Jr., Textbook of Polymer Science (3rd ed.), Wiley, New York, 1984. 

To date, poly(ferrocenylgermanes) have been much less studied than the silicon analogs, and they represent an interesting area for future work. Nevertheless, their thermal transition behavior has been explored (Table II) (57). Studies of the electrochemistry of the poly(ferrocenylgermane) 20 (R = R = Me) have shown that this material exhibits two reversible oxidation waves in CH2CI2, which indicates that the iron atoms interact with one another in a similar way to poly(ferrocenylsilanes) 63). 

The heat treatment affected the thermal transition behaviors and the LCTTs of PECs. The as-molded sample of PEC-70HBA exhibited two transitions at 240 C and 270 C. After annealing, the endotherm at lower temperature disappeared the endothermic peak at 270 C was shifted to the higher temperature. 

The A, C and D transltons are apparent, with A centered at about 49.5 C, C at 66 C and D at about 81 C. From Lysko s experiments at lower Ca " " concentrations, it seems that and 83 have merged with A and C, respectively (14). As pyran is added, the effects on B] and B2 are reversed, although B] is flattened as it is by pyran in the absence of Ca2+. in addition, the C transition is raised in temperature by about 3 . This again is not simply a depletion of membrane Ca, since even at 3.7 mg/ml of pyran (more than a 10-fold excess of pyran carboxylate as compared to Ca2+) the profile has not returned to its form in the absence of Ca, shown as the bottom curve. Some association is indicated, and this causes significant modification of the thermal transition behavior of the membrane. 

Figure 6. Thermal transition behavior of DPPC in multilamellar suspension in SOmM. Tris at pH 7.4. Key lower curve, DPPC I mg/mL middle curve, DPPC 1 mg/mL + pyran copolymer 1 mg/mC and upper curve, DPPC 1 mg/mC + pyran copolymer I mg/mL + CaCl, 5otM.

The conformation of the helical polypeptides changes from helical to nonhelical with an increase in temperature, and the glycopolypeptides and polypeptides show similar thermal transition behavior (not shown) (23). CD spectra for all other random coil and a-helical glycopolypeptides were recorded and found to be consistent with our previously reported data (23, 24) with some variations in absolute intensities, regardless of the identity of the saccharides used in the modification (Gal or Cap). These observations confirmed that the glycosylation of polypeptides with different saccharides does not significantly alter the secondary structure of the polypeptides. 

For thermal transition behavior of polymers, such as glass transition and melt transition, refer... 

Polyferrocenylsilanes in the solid state thermal transition behavior, morphology, and conformational properties... 

St neider NS, Desper CR, Singler RE (1976) The thermal transitions behavior of poly-organophosphazenes. J. Appl. Polymer Sci., 20 3087... 

K. Suri, A. Annapoomi, R.P. Tandon, C. Rath, and V.K. Aggrawal, Thermal transition behavior of iron oxide-polypyrrole nanocomposites, Curr. Appl. Phys., 3, 209-213 (2003). 

Thermal Transition Behavior, Morphology, and Conformational Properties... 

In order to obtain easily the exact value of 5 at a temperature, T, the possibility of 8p prediction from the thermal transition behaviors such as the glass transition and the melting has been discussed. Consequently, it was found that the sum of flieir transition enthalpies gave ho in equation [5.2.1] approximately ... 

Equations [5.2.2], [5.2.3] and [5.2.4] would be available as tools to predict 8 from thermal transition behaviors. 

The ROP route has been extended to the synthesis of other polymers from [l]fer-rocenophane precursors. Polyferrocenylgermanes (47) were first reported in 1993 and have been well-characterized and possess quite similar thermal transition behavior, morphology, and electrochemical behavior to the analogous polyferro-cenylsilanes (169). Poly(ferrocenylsilane-ferrocenylgermane) random copolymers (48) have also been prepared via the thermal pol5mierization of mixtures of the respective monomers (169). 

Thermal Transition Behavior and Morphology of Poly(ferrocenylsilanes)... 

The glass transition temperature (Tg) of poly(terf-butyhnethacrylate) (PtBMA) Langmuir-Blodgett (LB) films relative to that of spin-coated films on a silicon substrate was investigated by XR analysis. The XR analysis determined the thicknesses and surlace roughnesses of the LB films. Tg of spin-coated films on an oxide-free silicon wafer deaeases (s the film thickness decreases, which is consistent with the majority of the previous reports in the literamre. However, the transition temperature of the LB films is nearly independent of the total thickness, that is, the number of accumulated layers, which is much different from the case for spinthermal annealing of the LB film, it recovers the thermal transition behavior of the spin-coated film with an equivalent thickness. 

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