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Waterborne fluorinated polyurethane–acrylate hybrid emulsion modified by long aliphatic chains (WFPUA) is prepared by two steps, which include that the stearyl alcohol (SA)-blocked (end-capped) polyurethanes (SPU) are carried out in the mixtures of vinyl monomers, and then, the WFPUA is prepared via the free radical polymerization after the pre-emulsification of the said system. The characteristic of the reaction is the phase-inversion polymerization. The results show that the emulsifiability of SPU is firstly improved then decreased with the continuous increase in SA content. When the molar ratio of SA to 2-hydroxyethyl methacrylate (HEA) in the SPU is 1:1, the stability, zeta potential, viscosity and particle sizes of the WFPUA emulsion have the best results. The mechanical properties of WFPUA hybrid films deteriorate with the increase in SA content at 20 °C, but the mechanical properties of WFPUA films with more SA content achieve better results at 80 °C. The fluorinated groups migrated to the surfaces more easily with more SA content. In order to form the liquid crystalline-like structure on the WFPUA's surface, the gradient heating treatment to an elevated temperature (i.e., 120 °C) to properly orient the fluorinated chains is necessary. [ABSTRACT FROM AUTHOR]

ABSTRACT Crosslinking core-shell emulsions of waterborne fluorinated polyurethane-acrylate (WFPUA) were successfully synthesized using a solvent-free method. The crosslinkers of diacetone acrylamide and adipic dihydrazide were introduced into the WFPUA emulsions. The physical properties of hybrid emulsions such as the average particle size, stability, and viscosity were characterized. The core-shell of crosslinking WFPUA emulsion synthesized in this study was observed by transmission electron microscopy. Then, the results of Fourier transform infrared spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy indicated that the fluorinated monomer (FA) had been polymerized into the crosslinking waterborne polyurethane-acrylate polymer, and the fluorinated groups have evident enrichment on the film-air surface with the increase of FA content. At the same time, the thermal properties, water repellent/antifouling properties, and mechanical properties were measured. Moreover, the thermal properties and the elongation are raised but tensile stress and shore hardness are decreased with the increase of FA content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40970. [ABSTRACT FROM AUTHOR]

Through ultrasonic assisted radical polymerization, hydrophobically associating polyacrylamide (U-HAPAM) was prepared by acrylamide (AM), 2-acrylamido −2- methyl propane sulfonic acid (AMPS), and hydrophobic monomer octadecyl acrylate (ODA). The effects of concentration of initiator, ultrasonic frequency power and concentration of total monomers, had great influences on total monomer conversion, relative molecular mass and the viscosity of its aqueous solution. The macroscopic and microscopic self-assembly behaviors of the product was studied through apparent viscometry, fluorescence spectroscopy(FS) and atomic force microscope(AFM) respectively. The results showed that, the ultrasound possessed the certain ability of initiating and 0.3 % of initiator was advisable to use during the ultrasonic assisted radical polymerization to enhance the efficiency without substantially affecting the M; the thickening ability of the product was best under120W ultrasonic frequency power, of which the apparent viscosity attained 153.3 mPa · s as the concentration of U-HAPAM was 0.30 wt.%. Weighting the reaction efficiency and M, the concentration of total monomers was set as 10 % optimally. U-HAPAM achieved more excellent self-assembly performance and the critical association concentration of U-HAPAM prepared under these conditions was 0.27 wt.% (CAC) obtained from apparent viscometry and 0.23 wt.% (CAC') from FS. [ABSTRACT FROM AUTHOR]

The anionic hydrophobic association polyacrylamide (AFPAM) modified with fluorinated acrylate have been synthesized of acrylamide (AM), 2-acrylamide-2-methyl propanesulfonic acid (AMPS) and 2-(perfluorooctyl)ethyl acrylate (FEA) by free radical micellar copolymerization in aqueous solution utilizing sodium dodecyl sulfate(SDS) as the surfactant and potassium persulfate(KPS)/sodium bisulfite(SBS) as the redox initiator. The solution properties of these polymers were investigated. The results show that there are strong hydrophobic associations in the AFPAM aqueous solution. The intrinsic viscosity decreases and Huggins constant increases with the increase of hydrophobic FEA content. The addition of NaCl and CaCl2 results in an increase of solution viscosity which indicate the good salt-resistant performance. The polymers exhibit good temperature tolerance property, shear-thickening and thixotropy behavior. Additionally, the AFPAM has higher surface activity in salt solution than in water. [ABSTRACT FROM AUTHOR]

A novel cationic polyacrylamide modified with fluorinated acrylate had been synthesized of acrylamide (AM), methacryloxyethyl trimethylammonium chloride (DMC), and 2-(perfluorooctyl)ethyl acrylate (FEA) by free radical micellar copolymerization in aqueous solution utilizing cetyl trimethylammonium bromide (CTAB) as the surfactant and potassium persulfate (KPS)/sodium bisulfite (SBS) as the redox initiator. Some factors affecting synthesis, such as the amount of FEA, CTAB, and KPS, were described. Surface activity and flocculation of the polymer were studied. The results showed that with the incorporation of FEA, the intrinsic viscosity decreased until the modified polymer was not able to dissolve in water; and with the increase of CTAB and KPS, the intrinsic viscosity decreased firstly then increased slowly. The polymer exhibited good surface activity in both water and salt solution. Its flocculation properties were evaluated with kaolin suspensions using a standard jar test. The results demonstrated the superiority of the copolymer over the no-modified cationic polyacrylamide as a flocculant. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The dispersion of reduced graphene oxide (RGO) in polymer matrix was improved. • In situ incorporation of titanate functionalized RGO into polymer was used. • Isopropyl tri(diotylpyrophosphate) titanate (T3) was a good modifier for RGO. • The compatibility and interaction between T3-RGO and polymer were improved. • The one-component coating displayed excellent long-term corrosion resistance. Abstract Achieving a uniform dispersion of reduced graphene oxide (RGO) nanosheets in waterborne polymer matrix remains a challenge. Here, we significantly improved the dispersion stability of RGO in a polymer matrix through functionalizing RGO with titanate coupling agent of different dendritic structure. Titanate coupling agents of two branched dioctylpyrophosphate (T2) and three branched dioctylpyrophosphate (T3) were used. Rather than simply blending graphene with polymer matrix, functionalized graphene (T2-RGO or T3-RGO) was introduced into the reaction system with monomers to participate in the polymerization; resulting in improved compatibility and interaction between the graphene and polymer, especially for T3-RGO. One-component waterborne poly (urethane-acrylate) nanocomposite coatings (WPUA/T2G or WPUA/T3G) were then obtained. The particle size of WPUA/T3G colloidal particle size is much smaller than that of WPUA/T2G, the colloidal stability was also increased with the incorporation of T3-RGO. Compared with pure WPUA, the tensile strength of WPUA/T3G nanocomposite increased from 17.78 MPa to 40.01 MPa, and the elongation at break increased from 249% to 424%. The tensile strength and elongation at break of WPUA/T2G were 32.01 MPa and 366%, which were inferior to that of WPUA/T3G. Moreover, in comparison with pure WPUA, the impedance modulus of WPUA/T3G increased from 1.12 × 105 Ω.cm2 to 1.15 × 108 Ω.cm2, the coating resistance of WPUA/T3G increased from 8.41 × 104 Ω.cm2 to 1.39 × 108 Ω.cm2, which was also much higher than the impedance modulus (6.93 × 106 Ω.cm2) and coating resistance (7.31 × 106 Ω.cm2) of WPUA/T2G. WPUA/T3G nanocomposite coating exhibited excellent long-term corrosion resistance, being superior to the previously reported performance of solventborne polyurethane/graphene composite. [ABSTRACT FROM AUTHOR]