Self-assembly and rheological behaviors of intermacromolecular complexes consisting of oppositely charged fluorinated guar gums.
Carbohydr Polym 2018;
184:333-341. [PMID:
29352927 DOI:
10.1016/j.carbpol.2018.01.001]
[Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 11/23/2017] [Accepted: 01/01/2018] [Indexed: 12/12/2022]
Abstract
We synthesized fluorinated cationic/anionic guar gums (FCGG and FAGG) and characterized these species using Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy. The degree of fluorine substitution of FCGG (0.26%) and FAGG (0.21%) was calculated by elemental analysis. In addition, we explored the self-assembly and rheological behaviors of FCGG-FAGG complexes by viscometry, scanning electron microscopy, light scattering, fluorescence spectroscopy, and rheometry. The maximum viscosity and molecular weights were observed with a FAGG:FCGG mass ratio of 7.0:3.0, denoted by COMP. Moreover, FAGG-FCGG interactions in COMP led to the lowest shape factor and critical associating concentration. Additionally, the relaxation time and crossover modulus of COMP (6.65 s and 0.90 Pa, respectively) were remarkably higher than those of FCGG and FAGG alone. Finally, viscoelastic hysteresis loops emerged for FAGG and COMP. The results suggested that the self-assembly behaviors of FAGG-FCGG were influenced by both ionic and fluorinated groups.
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