Urethane Acrylate Monomers Research Articles

Characteristics of phosphorus‑nitrogen based flame-retardant monomers for UV-curable coatings on battery PET pouches

In this study, photocurable monomers containing phosphorus–nitrogen groups were employed alongside UV curing technology to develop flame-retardant (FR) coatings pouch-type battery cells made from polyethylene terephthalate (PET). Three different monomers were synthesized: a phosphorus-containing urethane acrylate monomer (DUPPO), a phosphorus–nitrogen-containing urethane acrylate monomer (DA-Pi-U), and a phosphazene-containing phenyl methacrylate crosslinker (CP-PMA). These monomers, recognized for their flame-retardant properties, were utilized in binary and ternary coating formulations that were effectively cured via a UV-curing process. The molecular architectures of the synthesized monomers were verified through 1H and 31P nuclear magnetic resonance spectroscopy. The rheological curing behavior of the coating solutions was assessed using an oscillatory rheometer. In addition, the reactivity of the FR coating system was examined via Fourier transform infrared spectroscopy. The thermal and flame-retardant characteristics of the FR coatings were confirmed through thermogravimetric analysis, Raman spectroscopy, limiting oxygen index measurements, and scanning electron microscopy. The ternary FR coating system with CP-PMA exhibited superior thermal stability, flame retardancy, crosslinking density, and mechanical robustness, making it suitable for PET pouches. Furthermore, optimal coating conditions for the slot coating process were determined using a viscocapillary model, enhancing practical applicability in industrial settings.

Synthesis of water-soluble tetrafunctional urethane acrylate bearing a pentaerythritol core and its radical polymerization behaviors in an aqueous solution

A novel water-soluble tetrafunctional urethane acrylate (TUA) was successfully synthesized by addition reaction of pentaerythritol to 2-isocyanatoethyl acrylate. TUA efficiently underwent radical polymerization and its copolymerization with monofunctional acrylate monomers exhibiting hydrophilicity in an ethanol aqueous solution, affording corresponding networked polymers in high yields. Notably, TUA exhibited much lower volume shrinkage during the radical polymerization compared to a comparative pentaerythritol core based tetrafunctional acrylate containing no urethane bonds. The thermal decomposition temperature of the networked homopolymer, synthesized from TUA, was much higher than those of the linear polymers, synthesized from monofunctional urethane acrylate monomers. TUA is expected to be applied to the development of environmentally sustainable polymer materials.

Development and Study of Biocompatible Polyurethane-Based Polymer-Metallic Nanocomposites.

IntroductionIn this work we selected components, developed technology and studied a number of parameters of polymer nanocomposite materials, remembering that the material would have high optical and good mechanical characteristics, good sorption ability in order to ensure high value of the optical signal for a short time while maintaining the initial geometric shape. In addition, if this nanocomposite is used for medicine and biology (biocompatible or biocidal materials or the creation of a sensor based on it), the material must be non-toxic and/or biocompatible. We study the creation of polymer nanocomposites which may be applied as biocompatible materials with new functional parameters.Material and MethodsA number of polymer nanocomposites based on various urethane-acrylate monomers and nanoparticles of gold, silicon oxides, zinc and/or titanium oxides are obtained, their mechanical (microhardness) properties and wettability (contact angle) are studied. The set of required, biology-related properties of these materials, such as toxicity and sorption of microorganisms are also investigated in order to prove their possible applicability.Results and DiscussionThe composition of the samples influences their microhardness and the value of contact angle, which means that varying with the monomer and the metallic, oxide nanoparticles composition, we could change these parameters. Besides it, the set of required, biology-related properties of these materials, such as toxicity and sorption of microorganisms were also investigated in order to prove their possible applicability. It was shown that the materials are non-toxic, the adhesion of microorganisms on their surface also could be varied by changing their composition.ConclusionThe presented polymer nanocomposites with different compositions of monomer and the presence of nanoparticles in them are prospective material for a possible bio-application as it is biocompatible, not toxic. The sorption of microorganism could be varied depending on the type of bacterias, the monomer composition, and nanoparticles.

Use of nanoindentation and nanoscratch experiments to reveal the mechanical behavior of sol–gel prepared nanocomposite films on polycarbonate

Sol–gel based UV cured hybrid coatings were prepared by combining different silanes with various urethane acrylate monomers. Effects of precursor concentration and inorganic to organic weight ratio were investigated. Nano indentation, nanoscratch and Taber tests were utilized to assess the behavior of the coatings. It was revealed that lower acrylic silane content and higher inorganic to organic weight ratios improved hardness, elastic modulus and scratch resistance. Increasing inorganic phase increased elastic modulus and hardness. Higher elastic modulus enhanced elastic recovery and scratch resistance of the films. Moderate level of hardness was found to perform better in abrasion resistance.

Photopolymerization behavior and phase separation effects in novel polymer dispersed liquid crystal mixture based on urethane trimethacrylate monomer

AbstractPolymer dispersed liquid crystals (PDLCs) are often formed by polymer induced phase separation, based on photopolymerization of multifunctional acrylate monomers. The emerged morphology is controlled by the interplay between polymerization rate and phase separation dynamics, which depends on different parameters such as monomer structure and functionality. In this work, a new PDLC formulation containing urethane trimethacrylate (UTMA) monomer is introduced, which has different molecular weight evolution, polymer gel point, and polymerization kinetics in comparison with some common ester acrylate (such as TMPTA and DPHPA) based PDLC compositions. UTMA is synthesized and characterized by Fourier transform infrared, 1H‐NMR, and 13C‐NMR spectroscopic techniques. Simultaneous examination of polymer evolution and LC phase separation by real‐time infrared spectroscopy shows that the UTMA based PDLC, which contains trifunctional urethane acrylate monomer, has greater amount of bond conversion, polymerization rate, and liquid crystal (LC) phase separation in comparison with TMPTA based PDLC. In spite of the acrylate monomers, which show gel point conversions as low as 1.83–5.72%, UTMA reaches to its maximum rate at 19.5% conversion, which causes higher phase separation and therefore greater LC domain size. The experimental results are explained more precisely by means of SEM and optical microscopy analyses. The results are confirmed by electro‐optics measurements. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Rapid Solid-State Photopolymerization of Cyclic Acetal-Containing Acrylates.

A cyclic acetal-functionalized urethane acrylate monomer is synthesized here and polymerized in a crystalline state without the polymerization kinetics being deleteriously affected by the solid state. Depending on the processing conditions, the cyclic acetal urethane acrylate monomer exists in either a metastable liquid state or a crystalline state at ambient conditions. Due to mobility restrictions, extremely poor polymerization kinetics and functional group conversions are typically achieved in solid state polymerizations. However, the solid-state photopolymerization of a cyclic acetal urethane acrylate results in nearly identical polymerization rates and ultimately higher conversion in the crystalline state than in the liquid state under otherwise identical conditions. We conclude that the crystallization process occurs in such a manner as to template the acrylic double bonds in a structure that facilitates rapid, minimally activated propagation.

Three-dimensional focal spots related to two-photon excitation

We used a photopolymer consisting of urethane acrylate monomer and free-radical-type initiators as a media for recording two-photon-excited (TPE) focal spots in three dimensions. Mathematically, the initiator plays a role of “k ” operator, transforming the quadratic light intensity distribution to a linear radical concentration distribution. Then, the monomer acts as a three-dimensional (3D) “film,” fixing the focal volume where radical concentration is above a threshold as a voxel. An ascending scan method was utilized to avoid substrate truncation and to achieve isolated complete 3D voxels, from which accurate forms of TPE focus were obtained. The 3D photographing technology led to a clear explanation of the origin of pronounced contradictions in reported spatial resolutions, and would be critical for laser precision microfabrication in various materials.

Synthesis and photoinitiated polymerization of a new urethane acrylate monomer: influence of polymerization temperature

The synthesis of a new urethane acrylate monomer (UAM) from hexamethylene diisocyanate trimer (HDT) and 2-hydroxyethyl methacrylate was performed by classical condensation. Physicochemical and thermal characterization of UAM was investigated ( Mn =1480 g mol −1; T g=−38°C) and no secondary reactions were observed. The photoinitiated polymerization of UAM with 2,2-dimethyl-2-hydroxy acetophenone (Darocur 1173) as radical photoinitiator was studied by using thermal photocalorimetry at different temperatures. Photoinitiator concentration (0.15% w/w) and light intensity (2.7 mW cm −2) were kept constant. The maximum conversion was obtained at 70°C. Above this temperature, thermal polymerization interfered with the photocalorimetric measurements.

Three-dimensional microfabrication with two-photon-absorbed photopolymerization

We propose a method for three-dimensional microfabrication with photopolymerization stimulated by two-photon absorption with a pulsed infrared laser. An experimental system for the microfabrication has been developed with a Ti:sapphire laser whose oscillating wavelength and pulse width are 790 nm and 200 fs, respectively. The usefulness of the proposed method has been verified by fabrication of several kinds of microstructure by use of a resin consisting of photoinitiators, urethane acrylate monomers, and urethane acrylate oligomers.