Comparison of phase structures and surface free energy values for the coatings synthesised from linear polyurethanes and from waterborne polyurethane cationomers

Abstract

WAXS, DSC and AFM methods were employed to compare phase structures of the coatings obtained from waterborne polyurethane cationomers which had been synthesised in the reaction of some diisocyanates (MDI, IPDI, TDI and HDI) with polyoxyethylene glycols (M = 600 and 2,000) and butane1,4-diol or N-methyl- or N-butyldiethanolamine and 2,2,3,3-tetrafluoro-1,4-butanediol. The structures were also analysed of the coatings derived from linear polyurethanes which had been synthesised on the basis of similar raw materials. Better rigidity was found for generally amorphous cationomer coats. Changes were discussed in the surface free energy (SFE) values and in their components, as calculated independently with the use of the van Oss–Good and Owens–Wendt methods. Polyurethane coats turned out more hydrophobic as compared to cationomer ones. In both coat types, fluorine incorporated into cationomers contributed to lower SFE values: from 50 down to about 30 mJ/m2.

Polyurethanes Containing an Imidazolium Diol‐Based Ionic‐Liquid Chain Extender for Incorporation of Ionic‐Liquid Electrolytes

“…Cation‐containing polyurethanes, or polyurethane cationomers, are an important class of polyurethane ionomers, which have found wide applications in protective coatings, biocides, antistatic agents, antimicrobial nanofilters, and polymeric colorants 1–3. A typical synthesis of polyurethane cationomers involves a tertiary amine‐containing diol as the chain extender and a subsequent alkylation of tertiary amine to generate ammonium cations.…”

Modelling the surface free energy parameters of polyurethane coats—part 1. Solvent-based coats obtained from linear polyurethane elastomers

“…16) in a vacuum drier, at 80 °C, over 6 h, followed by additional conditioning by exposure to ambient air during 10 days. The detailed information on polyurethane synthesis conditions was presented in our earlier paper [14]. The results of mechanical tests for these coatings confirm that the synthesised materials are elastomers and that their strength at about 40 MPa and elongation at a break of 40 % is sufficient for protective coatings.…”

“…Those impacts result from the presence of hydrogen bonds, from polarity of segments and their susceptibility to dispersion interactions. Our earlier WAXS investigations revealed that the obtained (applied) polyurethane coats contained max up to 20 % of crystalline phase which was composed principally of hard segments [14]. It is hence the polyurethane chemical structure to be critical for SFE.…”

“…Such analyses were not conducted for polyurethanes No. 9, 14 and 18, the synthesis of which involved TFBD since—as results from our earlier research [14]—the presence of fluorine atom(s) in the polyurethane chain makes the most decisive factor for the polarity of a polymer film. The κ exp and κ theor values for other polyurethanes can be found in Table 1.…”

Synthesis of UV-curable polycarbonate diols (PCDL)-based polyurethane acrylate for negative photoresist

“…Numerous articles have described the chemistry and processes used to manufacture PU [5][6][7]. The effects of various factors such as the structure and content of diisocyanates, polyols, hydrophilic groups and chain extenders on the preparation and properties of PU dispersions have been studied extensively [8][9][10][11][12]. Additionally, thermal phase separation and the physical properties of PU prepared from different polyols have also been investigated [13,14].…”