Effects of ion group content and polyol molecular weight on physical properties of HTPB‐based waterborne poly(urethane‐urea)s

Abstract

A series of waterborne poly(urethaneurea)s, WPUUs, based on using nonpolar hydroxyl-terminated polybutadiene (HTPB) as the soft segment, were successfully synthesized in this article. The effects of the COOH group content and soft-segment molecular weight (Mn s ) on the dispersion, morphology, and physical properties were investigated. Variations of the particle size, viscosity, and zeta potential were first governed by the hydrophilicity of the polymer chain, and then by the swelling derived from water. Fourier transfer infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) indicated that the degree of phase separation decreased as the COOH group content increased or as Mn s decreased. However, the hydrogen bonding between the soft and hard segments and the two-phase mixing could not occur in this nonpolar HTPB-based WPUU system, indicating that the hard segments tended to form smaller domains and to pack more loosely. It was attributed to the fact that the presence of bulky ionic salt groups destroyed the ordered arrangement of the hard segments. In this case, the increases of the interface area between the soft and hard phases resulted in that the present behaviors were similar to the phase mixing. In tensile properties, HTPB-based WPUUs exhibited higher tensile stress, elongation at break, and modulus as the COOH group content decreased or as Mn s decreased. In thermal degradation, the introduction of HTPB polyol improved the thermal stability of WPUU.

Synthesis, characteristic, and properties of waterborne polyurethane based on natural rubber

“…WPU has been performed in a wide range of commercial applications, including adhesives and coatings for various substrates 15, 16. Among the various types of polyols, which normally are synthesized from products of petroleum oil, used to synthesize WPU, polyether,16–18 polyester,19–21 or hydroxytelechelic polydienes15, 22–24 are generally used as soft segment in polyurethane structure. However, in the trend of increasing price and exhausting day over day of petroleum oil as well as environmental concerns (toxic waste or climate warming), a change from petroleum products with renewable sources is necessary for replacement development into the future 5, 10.…”

Synthesis and Application of a Low Dye Absorption Waterborne Polyurethane for Microfiber Synthetic Leather

“…The stretching vibration absorption peak and bending vibration absorption peak of the N-H bond were at 3372 and 1560 cm −1 . For the three carbon-carbon double bonds of HTPB, the three characteristic absorption peaks, located at 726, 967, and 909 cm −1 , respectively, indicate the 1,4-homeopathy, 1,4-trans, and 1,3-butadiene structures of HTPB [7,21,23].…”

“…In addition, various chain extender structures are added, such as 1, 4-butanediol (BDO), and ethylenediamine (EDA). The polyols form the soft segment, and the urethane bonds and urea bonds generated by the reaction of the diisocyanate and the chain extender form the hard segment; these segments are connected to each other by intermolecular forces and hydrogen bonds [7][8][9][10][11].…”