Protonated polymers

The resolution of infra-red densitometry (IR-D) is on the other hand more in the region of some micrometers even with the use of IR-microscopes. The interface is also viewed from the side (Fig. 4d) and the density profile is obtained mostly between deuterated and protonated polymers. The strength of specific IR-bands is monitored during a scan across the interface to yield a concentration profile of species. While in the initial experiments on polyethylene diffusion the resolution was of the order of 60 pm [69] it has been improved e.g. in polystyrene diffusion experiments [70] to 10 pm by the application of a Fourier transform-IR-microscope. This technique is nicely suited to measure profiles on a micrometer scale as well as interdiffusion coefficients of polymers but it is far from reaching molecular resolution. 

The pair-correlation function for the segmental dynamics of a chain is observed if some protonated chains are dissolved in a deuterated matrix. The scattering experiment then observes the result of the interfering partial waves originating from the different monomers of the same chain. The lower part of Fig. 4 displays results of the pair-correlation function on a PDMS melt (Mw = 1.5 x 105, Mw/Mw = 1.1) containing 12% protonated polymers of the same molecular weight. Again, the data are plotted versus the Rouse variable. 

Elastic and quasi-elastic (NSE) neutron scattering experiments were performed on dilute solutions of linear poly(isoprene) (PIP) polymers and of PIP stars (f = 4,12,18) [150]. In all cases the protonated polymers were dissolved in d-benzene and measured at T = 323 K, where benzene is a good solvent. Figure 50 shows the results of the static scattering profile in a scaled Kratky representation. In this plot the radii of gyration, obtained from a fit of the... 

EL pyridine-phenylene copolymers 564 [666] and 565 [667] have been synthesized and studied by Bryce and coworkers. Although a rather low el(<0.1%) was reported for the devices, an interesting phenomenon was found for polymers 565. When the PLED (ITO/PEDOT/565/Ca/Al) was fabricated using acidic solutions, a strong red shift in the EL band compared to that obtained with the neutral solution (from 510 to 575 nm) was observed. The authors explained this concept by planarization of the protonated polymer chain as a result of intramolecular hydrogen bonding N H- O. Variation of pyridine linkage in copolymers 565, 566, and 567 affects the PL and EL emissions (AEL = 444, 432,... 

The experiments on alkali iodides, PEOx-Nal or PEOx-Lil [316-318] were performed on PEO chains of 23 or 182 (-CH2-CH2-O-) monomers and Orion ratios between 15 and 50. The incoherent scattering from protonated polymers was measured using INI 1C, which yields the intermediate scattering function of the self-correlation. The experiments were performed in the homogeneous liquid phase where the added salt is completely dissolved and no crystalline aggregates coexist with the solution, i.e. at temperatures around 70 °C. 

The superscripts H-Cl refers to solvent proton-chlorine interaction, H-HS to solvent proton-proton interaction, and H-P to interaction of the solvent proton with the polymer. The latter should be dominated by solvent proton-polymer proton interaction. Upon addition of CDCI3, followed by extrapolation to pure CDCI3, the extrapolated rate [(1/Ti)q] is given by... 

Figure 9. Temperature and concentration dependence of the solvent proton-polymer proton relaxation rate (0), 10% polymer (X), 20% polymer.

The CP experiments on polymer blend systems, using a mixture of two polymers in which one is deuterated and another is protonated, have been carried out in order to elucidate their miscibility. This information is given by whether protons in the protonated polymer are cross-polarized to deute-rons of the other deuterated polymer or not. These studies show that effective CP transfer may be limited to about 10 A. In the... 

Alternative oxidants such as potassium iodate were also explored for the intrazeolite polymerization of aniline in NaY and acidic forms of Y zeolite. With peroxydisulfate, the polymerization proceeded only if a sufficient supply of intrazeolite protons was available. No polymer formed in either NaY or in acid zeolites with neutral iodate solution, but at low pH polyaniline was obtained in all hosts. The open nature of the zeolite host, even when partially filled with polymer, permits the introduction of base (such as ammonia). On admission of ammonia into the emeraldine salt-containing zeolite, the protonated polymer was converted into the neutral emeraldine base form. 

Due to its high speed, the cationic initiation reaction contributes to the over-all lactam consumption, in contrast to the anionic polymerization in which the disproportionation is usually very slow as compared with the fast propagation reactions involving acyllactam growth centres. Neutral and protonated polymer amide groups can also take part in the dispro-... 

The interpolymer CP from of a protonated polymer to of a deuter-ated polymer was applied to investigate the structure of the interfacial regions... 

Figure 5. Temperature dependence of peel force for Polymer I modified with 10 mot % ethylene glycol vs. protonated form at a peel rate of 12 in./min ( ) Polymer I modified, (O) protonated Polymer I modified ...

Protonation of Polymer I. The sodium cation associated with Polymer I was replaced with the hydrogen ion by acidifying an aqueous solution of Polymer I with IN hydrochloric acid. The protonated polymer was insoluble in water but soluble in organic solvents, especially chlorinated solvents. The bond strength of the protonated polymer was very poor (Figure 5). 

While the IR dichroism and NMR studies can give information about the conformation at individual bonds, the small-angle neutron scattering (SANS) measures the global conformation of the polymers (Cotton et al., 1974). SANS has been successfully utilized, for example by Hardouin and coworkers (Hardouin et al, 1991 Leroux et al, 1993), to establish the evolution with the temperature of the global shape of some mesogen-jacketed liquid crystalline polymers from isotropic to the nematic phase. A pseudobinary system of fully protonated polymer (P4,4,4) with the same polymer... 

Protonation of the 75% intrinsically oxidized NA powder or the fully oxidized PNA powder in aqueous media only gives rise to a 50% protonated polymer [69], with the Nls core-level lineshape of the protonated polymer not unlike that of the acid-protonated EM base [83]. In this case, protonation is accompanied by a substantial decrease in the intrinsic oxidation state of the polymer. The lack of any significant protonation of the amine nitrogen in these PAN powders by aqueous acid is similar to that observed in the EM powders, and may have resulted from excessive hydrolysis [89] of the powder samples due to their extended effective surface area. 

For homopolymer blends consisting of deuterated (labeled) polymer molecules randomly dispersed or dissolved in a protonated polymer matrix, small-angle neutron scattering in the Guinier region arises from the contrast between the labeled (deuterated) and the protonated species. The scattering cross-section can be expressed... 

In fact, neutron scattering studies show that coiled molecules have the same unperturbed dimensions as they would have in the appropriate dilute solution (see Figure 4-20). The experimental conclusion is independent of the method of preparation of the solid solution. In one case, such a solid solution was prepared by dissolving a protonated polymer in deuterated monomer and... 

Wong, C. K. L., So, M. R, and Dominic Chan, T.-W., Origins of the Proton in the Generation of Protonated Polymers and Peptides in Matrix-assisted Laser Desorption/Ionization, Eur. Mass. Spectrom., 4, 223,1998. 

The rate at which the initiating amines are incorporated is proportional to the basicity. As the conversion progresses, the concentration of protonated lactams in the reaction mixture decreases while that of the protonated polymer amide groups increases. The latter takes part in the initiation reactions with lactam molecules and in exchange reactions with polymer molecules ... 

The UV-vis-near-IR absorption spectrum of the solution of the protonated polymer exhibits MLCT bands and valence tautomerization similar to those of 1,8-Fc2Aq as shown in Fig. 3.32, indicating the formation of fulvene complexes in the main chain in solution. Infrared spectrum of the protonated polymer also shows the similarity with that of l,8-Fc2Aq, namely, half the CC triple bond remains. 

Bates FS, Wiltzius P (1989) Spinodal decomposition of a symmetrical critical mixture of deuterated and protonated polymer. J Chem Phys 91 3258-3274... 

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