Synthesis, characterization and photoinduced curing of polysulfones with (meth)acrylate functionalities

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)

Preparation and Characterization of Polyaspartic and a High Solids Acrylic Copolymer Polyol Based Polyurethanes

In this work, a high solids acrylic copolymer polyol (poly(MMA/BA/HEMA/AA)) was synthesized from the polymerization of methyl methacrylate (MMA), butyl acrylate (BA), hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) and was added to the polyaspartic resin. The polyaspartic-polyol mixtures reacted with polyisocyanates to create hybrid polyurethane-polyaspartic hybrid coatings. Different amounts of synthesized acrylic copolymer (5, 10, and 20% of total resin mixture) were mixed into polyaspartic resin and subsequently reacted with polyisocyanates in a 1:1 molar ratio. The characterization of the polymer was performed with Gel Permeation Chromatography (GPC), Fourier-Transform Infrared-Attenuated Total Reflection (FTIR-ATR) and Differential Scanning Calorimetry (DSC). The determination of physical and mechanical properties of the hybrid coatings was accomplished by hardness, glossiness, abrasion, stress-strain, corrosion, and impact tests. The results indicated that by adding high solids acrylic copolymer (HSAC), the drawbacks of polyaspartic resin (short pot life, hardness and brittleness, and poor adhesiveness) have been largely eliminated without reducing its intrinsic properties. The pot life increased from 16 minutes to 27 minutes and shore D hardness decreased from 60-65 to 52-55 as the polyol content increased in the mixtures. The acrylic polyols and aspartic mixtures may be used in the preparation of paints and varnishes applied on concrete, metal, and wood surfaces

Synthesis of self-curable polysulfone containing pendant benzoxazine units via CuAAC click chemistry

<p>Synthesis, characterization, and properties of new thermally curable polysulfone containing benzoxazine moieties in the side chain were investigated. First, chloromethylation and subsequent azidation processes were performed to form polysulfone containing pendant clickable azide groups. Independently, antagonist 3,4-dihydro-3-(prop-2-ynyl)-2H-benzoxazine was prepared by using paraformaldehyde, phenol and propargylamine. The following copper(I) catalyzed azide-alkyne cycloaddition click reaction was applied to obtain self-curable polysulfone with pendant benzoxazine units. The polymer and intermediates at various stages were characterized by ¹H-NMR, ¹³C-NMR and FT-IR spectroscopies. The thermal properties and curing behavior of final polymer were investigated by differential scanning calorimetry and thermal gravimetric analysis. Compared to the neat polysulfone, the obtained polymers exhibited thermally more stable polymers.</p