Determination for poly

In addition to the nature of the ester group, the structural isomerism of the polymer backbone also exerts some effect on the imidization characteristics [82]. Thus, for PMDA/ODA poly(amic ethyl ester) the pure para-isomer was found to imidize at slightly lower temperatures as compared to the pure metaisomer, see Fig. 10. This result is consistent with the report the amide groups exhibiting para-catenation represent the more favorable conformation for cyclization as determined for poly(amic acids) [83]. Results consistent with the... 

Table 1. Molecular weight determination for poly(4-methyl-l-pentene)...

Table 2. Potential values for the Cu /Cu redox change determined for poly-thia macrocyclic complexes in 80 % MeOH-20 % water (by weight) at 25 °C. (From Ref. [62])...

Fig. 6.1. The thermal expansion coefficient a of ice as determined for poly-crystalline samples by Jakob Erk (1928), — for single crystals by Hamblin...

For some polymers only anion exchange is observed. Then P = 0 and a, associated with the exchange of solvent molecules with one anion, can be determined. For poly(-3, 4-ethylenedioxythiophene) in LiClO/acetonitrile a = — 1 was found. This means one perchlorate anion substitutes one acetonitrile molecule. The experiments are also possible in aqueous electrolytes. Results for different anions in aqueous electrolytes are shown in Table ll.l.. ... 

The CNDO/2 MO calculation is the calculation for a molecule under vacuum. Astrup reported the geometry of 1,2-DME in the gas phase (at about 0°C) studied by the electron diffraction method.His assumption on the C—C bond length (1.504 A) may be too short in comparison with the bond length 1.54 A determined for poly(oxyethylene) by X-ray analysis. Since there is no other source, his geometry was used in this study. 

Trans/cis olefin ratios were also determined for poly(l-MeNB) and poly(NB) prepared with 3 and 4, respectively. In the first case, the trans/cis ratio is between 90 10 and 95 5, and in the latter... 

Figure 7 shows that the O3D term of conductivity of P30T is well fitted by Eq. 13 with a = 2.1 and = 0.18 eV. The latter value is close to that determined for poly (3-methylthiophene) and also to the energy of lattice phonons in P30T determined above. 

To illustrate the scaling law, sedimentation coefficients were determined for poly (ethylene oxide) (molecular weight 3 x 10 ) in aqueous solution as a function of the concentration. Data are as follows ... 

The temperature of the inverse temperature transition was determined for poly(VPAVG) as a function of concentration of polypentapeptide by means of the development of turbidity on raising the temperature. The temperature dependent aggregation was followed as turbidity at 300 nm using a CARY 14 spectrophotometer equipped with a 300 Hz vibrator in order to minimize settling during the temperature scan. Concentrations were varied from 100 mg/mL down to 0.15 mg/mL and the temperature was scanned from below 20 C to 60 C or more. 

Figure6.14 Equilibrium melting point determination for poly(ethylene oxide) in blends with styrene-acrylic acid (29 wt% AA) copolymers (reprinted (replotted) with permission of reference Jo, W. H.and Lee, S. C., Macromolecules (1990) 23, p. 2261, copyright (1990) American Chemical Society)...

Ns has been determined for poly(styrene) and poly(isobu-tyl methacrylate) for different temperatures. For decreasing temperatures, an increase in Ns has been found, supporting the ideas of the Adam-Gibss theory. ... 

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