Molecular Design of Brush-like Amphiphilic Statistical Tripolymers and Their Self-Assembly Behaviors

Abstract

It was found for the first time that the existence of hindrance units of sodium p-styrenesulfonate (SSS) on the polymer backbone could increase the hydrophobic content of the polymers on the premise of water solubility. A novel series of brush-like amphiphilic statistical tripolymers were designed and prepared by polymerization of amphiphilic macromonomer 2-(acrylamido)-dodecane sulfonic acid (AMC12S, 10 to 90 mole fraction), with SSS (0 to 5 mole fraction), and 2-(acrylamido)-2-methylpro­panesulfonic acid (AMPS). The self-assembly behaviors of these tripolymers were investigated using a combination of steady-state fluorescence, dynamic light scattering (DLS), and transmission electron micrograph (TEM) methods, mainly focusing on the effect of varying unit contents along the polymer backbone on the associative performance. The increase of amphiphilic units results in a simultaneous decrease of the microdomain polarity and the assembly size. Furthermore, the increase of hindrance units leads to an increase of assembly size but no change of microdomain polarity, manifesting a further aggregation of the polymer assemblies. The further aggregation partly results from the stretch facilitation of polymer chains by the hindrance units, and the facilitation effect works more intensely for the polymers with less amphiphilic units.

Self-assembly phenomena of the brush-like amphiphilic organopolysiloxanes in aqueous solution

“…Sample solutions for surface tension, fluorescence, DLS, and TEM measurements were prepared as the methods in our previous work . The polymer samples were dissolved in water, and the solutions were heated to ~90°C and then continually stirred for another 15 min.…”

“…The emission spectra were recorded on a Hitachi F‐4500 spectrofluorometer at 25.0 ± 0.5°C . The measurements were carried out with the excitation at 335 nm and the slit widths at 2.5 nm.…”

“…The DLS was carried out using a LLS spectrometer (ALV/SP‐125) with a multi‐τ digital time correlator (ALV‐5000) . Light (λ = 632.8 nm) from a solid‐state He–Ne laser (22 mW) was used as the incident beam.…”

Preparation of a crosslinked coating containing fluorinated water-dispersible polyurethane particles

“…17.50 mL of the initiator solution was added into the seed solution, and the mixture was heated to 85 • C after 30 min of the deoxidation under a nitrogen flow. The seed solution was allowed to undergo polymerization for 1 h, and the remaining two thirds of the mixed monomers (20.00 g) was gradually added into the reaction mixture over a period of ∼2 h. During this period, 35.00 mL of the initiator solution was simultaneously added dropwise, and the temperature was kept constant at 83-85 • C. After the dropwise addition period, the remaining 17.50 mL of the initiator solution was finally added into the reaction mixture, and the reaction was continued for 4 h to reduce the free monomer content. The resultant FWPU latex with a solid content of 30.00 wt% was filtered through a 50 mesh filter and collected.…”

“…Light ( = 632.8 nm) from a solid-state He-Ne laser (22 mW) was used as the incident beam. The measurements were conducted at a scattering angle of 90 • at a temperature of 25.0 ± 0.1 • C. The correlation function was analyzed via the CON-TIN method [35].…”