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© 2023, American Coatings Association.In this work, a novel bio-based phosphorus-containing reagent was synthesized and characterized. To obtain a flame retardant agent with acid functionality, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and bio-based itaconic acid were first reacted. The synthesized acid then was reacted with glycidyl methacrylate to form a difunctional phosphorus-containing methacrylate flame retardant monomer. The flame retardant monomer was added to a reactive monomer matrix with a photoinitiator to prepare UV-curable coatings. The molecular structure of the flame retardant was confirmed by Fourier-transform infrared-attenuated total reflection spectroscopy and proton nuclear magnetic resonance (1H NMR) spectroscopy. The flame retardant behavior of coatings was determined using limiting oxygen index. Thermal behaviors of the films were studied by thermal gravimetric analysis. Furthermore, scanning electron microscopy/energy-dispersive spectroscopy was used to determine the elemental composition and to observe the morphology of the coatings. The properties (water adsorption, gel content, etc.) of the coatings were also studied. It was found that the addition of DOPO resulted in a significant improvement in the flame retardant and thermal properties of the coatings.

In this study, the synthesis, characterization, and properties of a short oil length chain–stopped(rapid) alkyd resin is investigated. Gum rosin modified alkyd resin (RA-GR) was prepared using soybean oil, phthalic anhydride, glycerin and gum rosin acid. An alkyd modified with benzoic acid (RA-BA) was also prepared for comparison. FTIR analyses and GPC measurements of the alkyds were used for characterization. Other properties such as the viscosity, acid value, and solid content of the final resins were determined. Separately, the synthesized resins were used in paint formulations without any changes in other parameters such as filler, airdrying agents, solvents, etc. Paints were applied to metal and glass surfaces and the effect of gum rosin was investigated by looking at touch and hard drying times, adhesion to metals and gloss changes. Compared to the benzoic acid modified resin (RA-BA), gum rosin modified resin (RA-GR) exhibited remarkable positive effects on the paint with a better adhesion to the metals, and short drying times without any loses in the glosses.

Transparent conducting electrode (TCE) were prepared on a flexible polysulfone (PSU) film with a multilayer transfer of multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs) coated on glass substrates via layer-by-layer(LBL) deposition. First, bare CNTs were functionalized with carboxylic acid and amine moieties to obtain negatively and positively charged nanotubes, respectively. Second, functionalized CNTs were sequentially coated on a glass substrate via the LBL deposition, which was followed by subjecting the multilayer electrode to various chemical and thermal post-treatment processes to improve the electrical conductivity. Third, the multilayer was transferred from the glass substrate to the polymer film by coating and detaching the PSU. The highest figure of merit (FOM) was observed to be 2.52 x 10(-6) Omega(-1) at 68% optical transmission and 1.14 x 10(-3) Omega(-1) at 81% optical transmission for MWCNT and SWCNT films, respectively. Finally, the transparent electrode was demonstrated in a resistive touch sensor. (C) 2017 Elsevier B.V. All rights reserved.

This review summarizes the studies related to chemical functionalization of polysulfones used in many different applications such as membranes with special functions, nanocomposites, biofilm formation, fuel cells etc. reported in recent years from the literature since 2000. Various strategies have been applied for the functionalization of polysulfones. One strategy is to add desired functionality into starting monomers in the solution containing the main components of commercial polysulfones, the aromaticdihalidesulfoneandbisphenolmonomers,ortofunctionalizetherelatedmonomersbeforethecondensation.Another approachistoformdifunctionalpolysulfoneoligomers.Then,functionalgroupscanbeutilizedtoreactwithmonomersorother polymers to obtain functional polymers or block copolymers. The most applied method is post-modification of commercially available polysulfones by incorporation of functional groups to their aromatic groups and their use in the formation of graft polymers or polysulfone-based networks. c � 2013 Society of Chemical Industry

Synthesis of polysulfone-b-polystyrene (PSU-b-PS) block copolymers by a combination of condensation polymerization and free radical polymerization processes are described. First, a new macroazoinitiator (MAI) containing polysulfone (PSU) units was prepared by direct esterification of 4,4-azobis(4-cyanopentanoic acid) with α,ω-hydroxyl PSU telechelics at ambient conditions. The macroinitiator was then used in conventional free radical polymerization of styrene leading to the formation of desired block copolymers. In this process, initiating macroradicals were generated by thermal cleavage of the azo group present in the macroazoinitiator structure. The precursor polysulfone macroazoinitiator (PSU-MAI) and resulting block copolymers were characterized by spectral analysis using FT-IR, 1H-NMR, GPC, TGA, and DSC.

Crosslinked polysulfone/polyhedral oligomeric silsesquioxane (POSS) hybrid networks were synthesized in this work by photoinduced copolymerization of polysulfone dimethacrylate (PSU-DMA) and multifunctional POSS-methacrylamide (POSS-MAAm) with various feed ratios. The morphology of the nanocomposites was investigated by transmission electron microscopy (TEM), which suggests the random dispersion of POSS in the PSU matrix without macroscopic agglomeration. Thermogravimetric analysis results confirmed that the thermal stability and char yield of PSU-DMA/POSS-MAAm nanocomposites increased with the increase of POSS loading. Enhanced glass transition temperatures and storage modulus of the networks were observed to be higher than its precursor polymer.

Polymer-layeredclaynanocompositeshavegainedmuchattentioninindustryandinacademiabecausetheyexhibitsignificant improvements in materials properties such asthermal resistance, lower gas permeability, flame retar-dancy, solvent resistance, and mechanical propertiescomparedtotheneatpolymerormicro-andmacrocompo-sites.

Polysulfones with benzoxazine end groups (PSU-B-a) were obtained using monomer synthesis method from the phenol terminated polysulfone (PSU-OH), aniline and paraformaldehyde as starting materials. For this purpose, the precursor PSU-OHs with different molecular weights were prepared by condensation of bisphenol-A and bis(p-chlorophenyl) sulfone in presence of potassium carbonate. The structure of the polymers before and after functionalization was confirmed by proton nuclear magnetic resonance spectroscopy (H-1 NMR) and Fourier transform infrared spectroscopy (FT-IR). Thermally activated crosslinking behavior of these polymers was investigated by differential scanning calorimetry (DSC). Thermal and tensile properties of the crosslinked polymers obtained from PSU-B-a alone or with low molar mass benzoxazine (P-a) were studied by thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). (C) 2011 Elsevier Ltd. All rights reserved.

A new two-step method involving non-solvent induced phase separation (NIPS) and a UV curing process for the preparation of networked-polysulfone membranes is described. In this approach, first, methacrylated polysulfone macromonomers (PSU-DM)s were prepared by polycondensation followed by end-group esterification. PSU-DMs thin films containing phenylbis( 2,4,6-trimethylbenzoyl)phosphine oxide (BAPO) photoinitiator cast on glass plates were successively subjected to NIPS and UV curing processes to produce the ultrafiltration membranes. The reverse sequence, i.e. first UV-curing followed by NIPS was also applied. Although different double bond conversions were attained, both procedures essentially yielded structurally analogous membranes which were insoluble in DMF, DMSO, and boiling water. UV-curing behavior, structure, thermo-mechanical and morphological properties of the membranes were investigated. Regardless of the preparation sequences, membranes exhibited pure water permeability in the range of tight ultrafiltration membranes. (C) 2015 Elsevier Ltd. All rights reserved.

The novel axially dicarborane substituted silicon (IV) (SiPc-DC) phthalocyanine was synthesized by treating silicon phthalocyanine dichloride SiPc(Cl)(2) (SiPc) with o-Carborane monool. The compound was characterized by mass spectrometry, UV Vis, FT-IR, H-1 and B-11 Nuclear Magnetic Resonance Spectroscopy (NMR). Spectral, photophysical (fluorescence quantum yield) and photochemical (singlet oxygen (Phi(Delta)) and photodegradation quantum yield (Phi(d))) properties of the complex were reported in different solutions (Dimethyl sulfoxide (DMSO), Dimethylformamide (DMF) and Toluene). The results of spectral measurements showed that both SiPc and carborane cage can have potential to be used as sensitizers in photodynamic therapy (PDT) and boron neutron capture therapy (BNCT) by their singlet oxygen efficiencies (Phi(Delta)= 0.41, 0.39). (C) 2014 Elsevier B.V. All rights reserved.

Polysulfone/poly(ethylene glycol) amphiphilic networks were prepared via in situ photo-induced free radical crosslinking polymerization. First, the hydrophobic polysulfone diacrylate (PSU-DA) oligomer was synthesized by condensation polymerization and subsequent esterification processes. Then, the obtained oligomer was co-crosslinked with the hydrophilic poly(ethylene glycol) diacrylate (PEG-DA) or poly(ethylene glycol) methyl ether acrylate (PEG-MA) at different feed ratios. In the case of PEG-MA, the resulting network possessed dangling pendant hydrophilic chains on the crosslinked surface. The structure and the morphology of the membranes were characterized by attenuated total reflection infrared spectroscopy (ATR-IR) and scanning electron microscopy (SEM). The enhancement of surface hydrophilicity was investigated by water contact angle measurements. The biomolecule adsorption properties of these networks were also studied. The biomolecules easily adsorbed on the surface of the hydrophobic polysulfone networks whereas dangling hydrophilic chains on the surface prevented the adsorption of the biomolecules.

A diacrylate polysulfone oligomer is synthesized and used as the acrylic oligomer for the in situ synthesis of noble metal/PSU nanocomposites through UV-induced simultaneous radical polymerization of acrylic functionalities and NP formation by reduction of their precursors. Thus, silver or gold NPs are formed in situ during polymer network formation. FESEM analysis of the morphology of the cured systems demonstrates that the nanoparticles of the noble metals are homogeneously distributed in the network without macroscopic agglomeration.

The UV-curable telechelic polysulfones with (meth)acrylate functionalities were synthesized by condensation polymerization and subsequent esterification. The final polymers and intermediates at various stages were characterized by 1H NMR, FT-ATR, and GPC. The oligomeric films prepared from the appropriate solutions containing these telechelics and 2,2-dimethoxy-2-phenylacetophenone (DMPA) as the photoinitiator undergo rapid polymerization upon irradiation forming insoluble networks. The photo-curing behavior was investigated by photo-DSC and the effects of the molecular weight of the polysulfone precursor and type of functionality on the rate of polymerization and conversion were evaluated. Thermal properties of the photochemically cured films were studied by differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA).