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Synthesis and characterisation of coating polyurethane cationomers containing fluorine built-in hard urethane segments.

Król B, Król P, Pikus S, Chmielarz P, Skrzypiec K - Colloid Polym Sci (2010)

Bottom Line: Changes were discussed in the surface free energy and its components, as calculated independently according to the method suggested by van Oss-Good, in relation to chemical and physical structures of cationomers as well as morphology of coating surfaces obtained from those cationomers.Fluorine incorporated into cationomers (about 30%) contributed to lower surface free energy values, down to about 15 mJ/m(2).That was caused by gradual weakening of long-range interactions within which the highest share is taken by dispersion interactions.

View Article: PubMed Central - PubMed

ABSTRACT
Polyurethane cationomers were synthesised in the reaction of 4,4'-methylenebis(phenyl isocyanate) with polyoxyethylene glycol (M = 2,000) or poly(tetrafluoroethyleneoxide-co-difluoromethylene oxide) α,ω-diisocyanate and N-methyl diethanolamine. Amine segments were built-in to the urethane-isocyanate prepolymer in the reaction with 1-bromobutane or formic acid, and then they were converted to alkylammonium cations. The obtained isocyanate prepolymers were then extended in the aqueous medium that yielded stable aqueous dispersions which were applied on the surfaces of test poly(tetrafluoroethylene) plates. After evaporation of water, the dispersions formed thin polymer coatings. (1)H, (13)C NMR and IR spectral methods were employed to confirm chemical structures of synthesised cationomers. Based on (1)H NMR and IR spectra, the factors κ and α were calculated, which represented the polarity level of the obtained cationomers. The DSC, wide angle X-ray scattering and atom force microscopy methods were employed for the microstructural assessment of the obtained materials. Changes were discussed in the surface free energy and its components, as calculated independently according to the method suggested by van Oss-Good, in relation to chemical and physical structures of cationomers as well as morphology of coating surfaces obtained from those cationomers. Fluorine incorporated into cationomers (about 30%) contributed to lower surface free energy values, down to about 15 mJ/m(2). That was caused by gradual weakening of long-range interactions within which the highest share is taken by dispersion interactions.

No MeSH data available.


Three-dimensional AFM 500 × 500 nm image for cationomer no. 2, obtained by the “moderate tapping” method
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Fig8: Three-dimensional AFM 500 × 500 nm image for cationomer no. 2, obtained by the “moderate tapping” method

Mentions: More interesting arrangements can be seen in AFM method. Figures 8 and 9 present AFM micrographs for cationomers nos. 2 and 4. What can be seen is strongly superior separation of phases in sample no. 4 as well as fragments of very thin fibrils which were formed within the hard phase. Images of the surface shape recorded with AFM method, visible on these micrographs phase inhomogeneity and on the basis of the results of the WAXS analysis, in our opinion, can assign received cationomers certain ability to create thermodynamic stable crystalline structures. That alone makes a proof for orderly arrangement of supermolecular structures. That fact may not be uninfluential on the energy performance of the sample which was quantitatively analysed by the van Oss–Good method. This method is reflecting long-range interactions (γSLW) and acid–base interactions (γSAB) which the chemical structure of polyurethane chains and their orientation character in the range of domain built from soft and hard segments are deciding. Of course shouldn’t chemical structure of polymer in the aspect of it influence on surface properties overrate, because other factors connected with, e.g. the technique of producing polymer sample as the coating, fibre or the product about character of the polyurethane foam or the elastomer can perform. For the presented work it is essential that all analysed samples were obtained in the same way (Table 4).Fig. 8


Synthesis and characterisation of coating polyurethane cationomers containing fluorine built-in hard urethane segments.

Król B, Król P, Pikus S, Chmielarz P, Skrzypiec K - Colloid Polym Sci (2010)

Three-dimensional AFM 500 × 500 nm image for cationomer no. 2, obtained by the “moderate tapping” method
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2927047&req=5

Fig8: Three-dimensional AFM 500 × 500 nm image for cationomer no. 2, obtained by the “moderate tapping” method
Mentions: More interesting arrangements can be seen in AFM method. Figures 8 and 9 present AFM micrographs for cationomers nos. 2 and 4. What can be seen is strongly superior separation of phases in sample no. 4 as well as fragments of very thin fibrils which were formed within the hard phase. Images of the surface shape recorded with AFM method, visible on these micrographs phase inhomogeneity and on the basis of the results of the WAXS analysis, in our opinion, can assign received cationomers certain ability to create thermodynamic stable crystalline structures. That alone makes a proof for orderly arrangement of supermolecular structures. That fact may not be uninfluential on the energy performance of the sample which was quantitatively analysed by the van Oss–Good method. This method is reflecting long-range interactions (γSLW) and acid–base interactions (γSAB) which the chemical structure of polyurethane chains and their orientation character in the range of domain built from soft and hard segments are deciding. Of course shouldn’t chemical structure of polymer in the aspect of it influence on surface properties overrate, because other factors connected with, e.g. the technique of producing polymer sample as the coating, fibre or the product about character of the polyurethane foam or the elastomer can perform. For the presented work it is essential that all analysed samples were obtained in the same way (Table 4).Fig. 8

Bottom Line: Changes were discussed in the surface free energy and its components, as calculated independently according to the method suggested by van Oss-Good, in relation to chemical and physical structures of cationomers as well as morphology of coating surfaces obtained from those cationomers.Fluorine incorporated into cationomers (about 30%) contributed to lower surface free energy values, down to about 15 mJ/m(2).That was caused by gradual weakening of long-range interactions within which the highest share is taken by dispersion interactions.

View Article: PubMed Central - PubMed

ABSTRACT
Polyurethane cationomers were synthesised in the reaction of 4,4'-methylenebis(phenyl isocyanate) with polyoxyethylene glycol (M = 2,000) or poly(tetrafluoroethyleneoxide-co-difluoromethylene oxide) α,ω-diisocyanate and N-methyl diethanolamine. Amine segments were built-in to the urethane-isocyanate prepolymer in the reaction with 1-bromobutane or formic acid, and then they were converted to alkylammonium cations. The obtained isocyanate prepolymers were then extended in the aqueous medium that yielded stable aqueous dispersions which were applied on the surfaces of test poly(tetrafluoroethylene) plates. After evaporation of water, the dispersions formed thin polymer coatings. (1)H, (13)C NMR and IR spectral methods were employed to confirm chemical structures of synthesised cationomers. Based on (1)H NMR and IR spectra, the factors κ and α were calculated, which represented the polarity level of the obtained cationomers. The DSC, wide angle X-ray scattering and atom force microscopy methods were employed for the microstructural assessment of the obtained materials. Changes were discussed in the surface free energy and its components, as calculated independently according to the method suggested by van Oss-Good, in relation to chemical and physical structures of cationomers as well as morphology of coating surfaces obtained from those cationomers. Fluorine incorporated into cationomers (about 30%) contributed to lower surface free energy values, down to about 15 mJ/m(2). That was caused by gradual weakening of long-range interactions within which the highest share is taken by dispersion interactions.

No MeSH data available.