Series Of Methacrylates Research Articles

Studying the Interaction of Viteral Substitutes with the Surface of Acrylic Intraocular Lenses

Purpose of the study: In vitro to study the degree of adhesion of vitreous substitutes, such as silicone oil of various viscosities and perfluorodecalin (PFOS), to hydrophobic acrylic polymer IOLs and evaluate the interaction of vitreous substitutes with the model MIOL-Soft-23 in the clinic. Material and methods. IOLs of the model MIOL-Soft-23 were taken for the experiment. MIOL-Soft-23 are included in the RPR-20 set. IOL of the model MIOL-Soft-23 is made by photopolymerization from a biocompatible spatially cross-linked hydrophobic acrylic polymer based on oligomers and monomers of the methacrylic series with filters in the ultraviolet region of the spectrum from 19 to 23 D. For the experiment, silicone oils of different viscosities were taken: RS-OIL 2000 (Alchimia), SIL-5000-S (DORC), Oxane 5700 (Bausch & Lomb), PFOS (perfluorodecalin) Dk-line (Bausch & Lomb). Also, saline sodium chloride 0.9 % (Solofarm) was used. Results. Revealed a decrease in the degree of silicone adhesion to the surface of acrylic hydrophobic IOLs as the temperature rises, not less than 1.5 %. The absence of dependence of the degree of adhesion on the degree of viscosity of silicone oil was confirmed, which corresponds to the literature data. For the first time, the average percentage of adhesion of perfluorodecalin to the IOL surface data were obtained, in particular, the MIOL-Soft-23 model. The range of values ranged from 0.7 to 7.2 %. The average coverage percentage is 1.9 ± 1.3 % (exposure at 37 ± 1 °C for up to 14 days) and 3.4 ± 1.5 % (exposure at room temperature for up to 14 days). This confirms the need for careful intraoperative monitoring of the completeness of removal of PFOS droplets from the IOL surface. Conclusion. The presence of the risk of adhesion of residual drops of silicone oil and PFOS to the surface of the IOL necessitates careful intraoperative control of the completeness of the removal of vitreous body substitutes, as well as further search for the best ways to eliminate this complication. The conducted complex of studies makes it possible to recommend the use of IOL model MIOL-Soft-23 in complicated cases of vitreal surgery.

Morphology Control via RAFT Emulsion Polymerization-Induced Self-Assembly: Systematic Investigation of Core-Forming Blocks.

Polymerization-induced self-assembly (PISA) is a useful formulation for readily obtaining nanoparticles from block copolymers in situ. Reversible addition–fragmentation chain-transfer (RAFT) emulsion polymerization is utilized as one of the PISA formulations. Various factors have so far been investigated for obtaining nonspherical particles via RAFT emulsion polymerization, such as the steric structure of the shell, the glass-transition temperature (Tg) of the core-forming block, and the water solubility of the core-forming monomer. This study focuses on core-forming blocks without changing the structure of the shell-forming block. In particular, we elucidate the balance between Tg for the core-forming block and the water solubility of the core monomer. A series of alkyl methacrylates, such as methyl methacrylate (MMA), ethyl methacrylate (EMA), and n-propyl methacrylate (PrMA), are emulsion-polymerized in the presence of a poly[poly(ethylene glycol) methyl ether methacrylate] (PPEGMA) macromolecular chain-transfer agent via the RAFT process. The resulting in situ morphology changes to form shapes such as spheres, worms (toroids), and vesicles are systematically investigated. The properties of the core that determine whether a morphological change occurs from spheres are (i) the solubility of the core-forming monomer in water, (ii) the relationship between Tg for the core-forming block and the polymerization temperature, and (iii) the hydrophobic core volume, which changes the packing parameter. These factors allow prediction of the block copolymer morphology produced during RAFT emulsion polymerization of other methacrylates such as n-butyl methacrylate (BuMA), tetrahydrofurfuryl methacrylate (THFMA) with physical properties of the homopolymer (poly(tetrahydrofurfuryl methacrylate) (PTHFMA)) between those for poly(MMA) (PMMA) and PBuMA, and 1-adamantyl methacrylate (ADMA) with low monomer solubility in water and high Tg of the homopolymer (PADMA).

Adhesion Strength of Organic-Inorganic Terpolymers Containing Nanostructured Poly(Titanium Oxide) with Self-Cleaning Properties to Different Materials

Optically transparent organic-inorganic terpolymers based on poly (titanium oxide), hydroxyethyl methacrylate and organic monomers of the vinyl and (meth) acrylic series (acrylonitrile, butyl methacrylate, vinyl butyl ether, 2-ethylhexyl acrylate) were obained as a coating on silicate glass, polycarbonate, touch-up paint and metal. Materials’ light transmittance in the visible spectral range is 87 - 92% depending on the composition. The adhesion of terpolymers’ thin layers to substrates of various natures was investigated under shear deformations and by the lattice notch method according to ISO 15140. It was found that it is necessary to selectively excerpt composition of terpolymers in accordance with the nature of the substrate for creation adhesive durable coatings. The most durable coatings are formed on glass, polycarbonate and automotive enamel. It was revealed that the nature of the substrate and the composition of organic-inorganic terpolymers affect the hydrophobicity of the coatings and their ability to hydrophilize under the influence of UV-irradiation. The contact wetting angle of coatings with water, on average, reversibly varied within ~ 90 ° ↔ ~ 30 °.

Occupational Methacrylate Allergy in Dental Personnel

Purpose of the article: Acrylate and methacrylate (MA) use in the dental industry is widespread, being utilized in dental prostheses and composite resins, dentin bonding materials, and glass ionomers. However, occupational methacrylate allergy in dental personnel is a growing phenomenon. The aims of this retrospective observational study are to evaluate the risk of occupational contact dermatitis following exposure to methacrylates in dental personnel and to identify possible preventive measures. Materials and Methods: A total of 126 subjects exposed to acrylic and methacrylic resins in their professional context and who reported clinical manifestations were included from our outpatient department database. These were subdivided into two groups: 81 dental technicians and 45 dental hygienists. All the subjects had undergone patch testing with a “methacrylate series” (FIRMA) and readings were taken after 2 days (D2), 4 days (D4), and 7 days (D7). Results: A significantly higher incidence of methacrylate allergy was found in the dental technician group compared to the dental hygienists. Among the dental technicians, 40.7% of the subjects presented skin manifestations. The hands were the most frequently affected sites. Conclusion: Our results confirm the high sensitizing potential of MA in the workplace for dental personnel and in particular an increased professional risk in work where the hands are directly involved (dental technicians). Patch testing as an integrated part of a screening tray is needed for a complete evaluation of occupational skin allergy due to MA in dental personnel. The adoption of proper primary preventive measures, including gloves, protective eyewear, face shields, and disposable gowns, can be useful in preventing new cases of contact dermatitis, which may lead to a change of occupation in dental personnel.

Renewable UV-curable polyester methacrylate/cellulose nanocrystals composite resin for wood waterproof coating

Low-viscosity UV-curable resins are widely used in industry as they allow for UV curing materials with reduced amounts of reactive diluents to adjust the viscosity. But their mechanical properties and waterproof performance after curing as UV coatings still need to be improved. Here, a series of low-viscosity bio-based UV-curable polyester methacrylates were synthesized through L-lactide (LA) and ε-caprolactone (CL) monomers. The results show that the introduction of star-shaped structure and random copolymerization of LA and CL can effectively reduce the viscosity of the resin to 313 mPa · s and at the same time increase the double bond conversion rate and maintain good mechanical properties. The composite resin was prepared by blending the star-shaped low-viscosity polyester methacrylate resin with cellulose nanocrystals (CNCs), and the microstructure was characterized by XRD and TEM. The curing kinetics, mechanical properties, thermal properties and waterproof properties of the composite resin were further tested. When the mass fraction of CNCs is 2.5 wt%, the water absorption rate of the pine samples coated with UV-cured composite resin is reduced to 17%, which is 65% lower than that of the uncoated samples and 20% lower than that of the samples coated with resin without CNC. This article provides a feasible and effective method for improving the mechanical properties and waterproof performance of low-viscosity UV-curing resins.

Dermatite de Contato Alérgica aos (Meta)Acrilatos- estudo retrospetivo de sete anos num Hospital Público Português

Introduction Acrylates are salts or esters of the acrylic acid, widely used as part of cosmetic or dental products, surgical equipment, medical devices, household items, building materials and printing inks. Allergic contact dermatitis (ACD) caused by (metha)acrylates could be described in occupational settings, mainly in beauticians using acrylic manicure and, specifically, the photo-bonded long-lasting nail polish. The use of gloves, fingertips made of Polyethylene/ Ethylvinyl-alcohol, mask, safety glasses and an appropriate uniform are recommended in these cases. Materials and methods We present a retrospective study of ACD to acrylates diagnosed at an Hospital in Braga (Portugal), between January 2012 and March 2018. In all cases the epicutaneous patch tests used included the Portuguese Contact Dermatitis Research Group baseline series and an extended series of (meth)acrylates. Results A total of 39 female patients had a sensitization to (metha)acrylates, aged between 21-66 years, with personal history of atopic eczema and allergic rhinitis in 23 and 26% of cases, respectively. The most frequent presentation was hand eczema (87%). Dorsal and palms were affected in an equal percentage of cases (38%) and nail dystrophy in 8% of patients. Ectopic lesions on the face were detected in 33% of cases, mostly with the involvement of the eyelids. Occupational related exposure due to (metha)acrylates was found in 69% of cases, mostly of them beauticians/ artificial nail technicians. The most common sensitizers among the 39 allergic individuals were 2-hydroxyethyl methacrylate (HEMA; positive in 97% of cases) and ethyleneglycol dimethacrylate (positive in 69% of cases). Conclusion In our population, we highlight the high number of cases of ACD from (meth)acrylates in relation to artificial nails. Concerning to the health and safety of workers, it certainly deserves better preventive measures at the occupational level and specific regulation from the authorities concerned with the safety of consumers. HEMA was the most frequent positive allergen (above 90% of tests) and, in agreement with previous studies, can be considered a good screening allergen.

New Antimicrobial Biomaterials for the Reconstruction of Craniofacial Bone Defects

Reconstructive bone surgery of the head and neck could prove challenging in terms of postoperative healing and recovery. Fighting infection during the healing period is one of the critical factors of the long-term survival of an implant. The aim of the study was to develop an innovative composition suitable for an antibacterial craniofacial implant that should have the capacity to continuously and constantly release the amount of gentamicin necessary to prevent the post-surgical infections. For this purpose, a series of composite materials based on dimethacrylic monomers, hydroxyapatite and ZrO2, with (series B) or without the addition of polymethyl methacrylate (series A), reinforced with woven E-glass fibers (FRC) were obtained using the laminate lay-up process. Gentamicin was included in all FRC sample matrices to confer an antimicrobial effect. The results show that after extraction of the residual monomers from the FRC samples in different solvents (chloroform, acetone and ethyl alcohol), the cumulative amount of released gentamicin after 12 days was between 7.05–11.38 mg for A samples and 11.21–14.52 mg for B samples. The microbiological protocol showed that gentamicin induces a two weeks-lasting antimicrobial effect maintained over the minimal inhibitory concentration for P. aeruginosa and S. aureus.

Microscopic morphology, rheological behavior, and mechanical properties of polymers: Recycled acrylonitrile‐butadiene‐styrene/polybutylene terephthalate blends

ABSTRACTIn this study, styrene‐acrylonitrile‐glycidyl methacrylate (SAG) series copolymers were specially designed for producing the recycled acrylonitrile‐butadiene‐styrene (rABS)/poly(butylene terephthalate) (PBT)/SAG blends, which were prepared through the process of continuous melt blending and batch feeding. The effects of viscosity composition, SAG chemical composition, and SAG content on the morphology, and rheological and mechanical properties of the blends have been investigated. As demonstrated by morphological observation, the variety of viscosity composition of the blends affects the size of dispersed PBT droplets. Moreover, high viscosity of rABS matrix seems to facilitate the formation of smaller dispersed phase size of blends. Various SAG chemical compositions have different stabilities on the morphology of the blends, which affects the deformation, fragmentation, and coalescence of dispersed phase droplets. In addition, a finer phase morphology can be achieved when the density distribution of epoxy group is optimal in SAG copolymer. Rheological characterization manifested that the rheological properties of the blends depends strongly on its composition and structure, while the crosslinking degree is associated with the concentration of reactive groups and extent of reaction. Thereby, the rheological behavior of the blends during processing can be controlled by changing the reactive sequence and adding the quantity of epoxy group. The test on mechanical properties verified that a recycled product with excellent performance can be obtained by altering processing methods and the blends formula, which may be further applied to the 3D printing materials required by fused deposition modeling technology. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48310.

Night-time atmospheric degradation of a series of butyl methacrylates

Rate coefficients for the reactions of NO3 with n-butyl methacrylate (k1), iso-butyl methacrylate (k2) and tert-butyl methacrylate (k3) have been determined at 298K and atmospheric pressure using the relative rate method. The following rate coefficients (×10−15cm3molecule−1s−1) were obtained for the first time: k1=(5.5±2.6), k2=(5.8±2.8) and k3=(5.6±2.5).The NO3 reactions of these compounds could contribute to the removal of NOx and as NOy reservoirs. The potential importance for the tropospheric nitrogen budget of these reactions is discussed and atmospheric lifetimes for the butyl esters are calculated.

Uranyl Complexes with (Meth)acrylate Anions

AbstractTwo isostructural series with general formulae [R(H2O)6][UO2(CH2CHCOO)3]2 (R = Mg, Co, or Ni) and [R(H2O)6][UO2{CH2C(CH3)COO}3]2·8H2O (R = Mg or Zn) have been synthesized and characterized by single‐crystal X‐ray diffraction and IR spectroscopy. The acrylate and methacrylate series of complexes crystallize in the monoclinic crystal system with the space groups P21/c and P21/n, respectively. The crystal structures of all the studied compounds have similar main structural units, specifically, octahedral aqua complexes [R(H2O)6]2+ and tris(carboxylato) complexes [UO2L3]– (L = acrylate or methacrylate anion). Despite this, there are significant structural differences between the two series that lead to the inclusion of outer‐sphere water molecules in the structures of the methacrylate series. The intermolecular interactions in the acrylate series were studied by the method of molecular Voronoi–Dirichlet polyhedra and compared with those in previously studied acetate compounds. The structures of the methacrylate series of complexes demonstrate an important role of π···π interactions in the molecular packing of the complexes.

Synthesis and radical polymerization of methacrylate endowed with bicyclobis(γ‐butyrolactone) moiety through methylene linker

ABSTRACTA series of methacrylates bearing bicyclobis(γ‐butyrolactone) (BBL) moiety were synthesized and radically polymerized to afford the corresponding poly(methacrylate)s bearing BBL moiety in the side chain, with expecting that the high polarity and rigidity of BBL would be inherited by the polymers. The resulting polymers were soluble in polar aprotic solvents such as dimethyl sulfoxide and N,N‐dimethylformamide because of the high polarity of the BBL moiety. The glass transition temperatures (Tg) of the polymers depended on the length of methylene linker that tethered the methacrylate and BBL moieties, making the use of shorter linkers lead to higher Tgs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2462–2468

Patch testing in oral lichenoid lesions of uncertain etiology.

The benefit of patch testing patients with oral lichenoid lesions (OLL) is still debated. We assessed the results of patch testing in patients with multiple amalgams and multiple OLL, where the etiology of the oral mucosal disease was unclear. Patients referred from an oral medicine clinic were patch tested to the British Society of Cutaneous Allergy standard series, dental and materials series, and, in 1 patient, the dental methacrylate series also. Patients' responses to amalgam removal were assessed during a mean follow-up of 2.6 (range, 0-4.75) years. Thirty-one patients with OLL were referred for patch testing. Ten (32%) patients tested positively to mercury. Eight patients with positive reactions to mercury had amalgam removal, with complete or partial resolution of the OLL in all cases (100%). Patients with OLL of unclear etiology adjacent to large amalgam restorations should be investigated for delayed contact hypersensitivity. Removal of amalgams in patients with positive patch test reactions to mercury results in improvement or resolution of the OLL in most patients.

Designing breathable superhydrophobic cotton fabrics

Superhydrophobic cotton fabrics were prepared through radiation induced graft polymerization by applying a series of alkyl methacrylates as the functional monomers.

Effect of polymer matrix and photoacid generator on the lithographic properties of chemically amplified photoresist

Resistive compositions based on ter-copolymers of isobornylacrylate with methylmethacrylate and (meth)acrylic acid, which are synthesized using the controlled radical polymerization with reversible chain transfer, as well as triphenylsulphoniumtriflate as a photo-sensitive catalyst are studied. The effect of the chain-transfer agent, as well as the composition and molecular weight of the copolymer on the sensitivity of the resists to UV radiation (222 nm), is determined. Using the ter-copolymer of tert-butoxycarbonyloxystyrene with methylmethacrylate and methacrylic acid, the dependence of the lithographic properties of the photoresist on the chemical composition of the photoacid generator is analyzed. The plasma-chemical stability of (co)polymer resists of methacrylic series in the plasma of Ar + SF6 is studied.

Material stiffness effects on neurite alignment to photopolymerized micropatterns.

The ability to direct neurite growth into a close proximity of stimulating elements of a neural prosthesis, such as a retinal or cochlear implant (CI), may enhance device performance and overcome current spatial signal resolution barriers. In this work, spiral ganglion neurons (SGNs), which are the target neurons to be stimulated by CIs, were cultured on photopolymerized micropatterns with varied matrix stiffnesses to determine the effect of rigidity on neurite alignment to physical cues. Micropatterns were generated on methacrylate thin film surfaces in a simple, rapid photopolymerization step by photomasking the prepolymer formulation with parallel line–space gratings. Two methacrylate series, a nonpolar HMA-co-HDDMA series and a polar PEGDMA-co-EGDMA series, with significantly different surface wetting properties were evaluated. Equivalent pattern periodicity was maintained across each methacrylate series based on photomask band spacing, and the feature amplitude was tuned to a depth of 2 μm amplitude for all compositions using the temporal control afforded by the UV curing methodology. The surface morphology was characterized by scanning electron microscopy and white light interferometry. All micropatterned films adsorb similar amounts of laminin from solution, and no significant difference in SGN survival was observed when the substrate compositions were compared. SGN neurite alignment significantly increases with increasing material modulus for both methacrylate series. Interestingly, SGN neurites respond to material stiffness cues that are orders of magnitude higher (GPa) than what is typically ascribed to neural environments (kPa). The ability to understand neurite response to engineered physical cues and mechanical properties such as matrix stiffness will allow the development of advanced biomaterials that direct de novo neurite growth to address the spatial signal resolution limitations of current neural prosthetics.

Macromol. Chem. Phys. 20/2013

Front Cover: A series of methacrylates, containing bisphosphonate, bisphosphonic acid, carboxylic acid, or both acids together are synthesized, with a view for use as dental adhesives, due to their hydrolytic stability, the properties of their copolymerizations with commercial dental monomers, and hydroxyapatite interactions. The bisphosphonic acid-containing monomers show good performance in terms of solubility, acidity, and copolymerizability with 2-hydroxyethyl methacrylate (HEMA) in water and HEMA/glycerol dimethacrylate (GDMA) in bulk. Further details can be found in the article by Prof. D. Avci* and co-workers on page 2324.

Preparation of a polyhedral oligomeric silsesquioxane-based perfluorinated monolithic column

A monolithic column with high affinity to fluorous compounds was prepared using a polyhedral oligomeric silsesquioxane (POSS) reagent as the cross-linker and pentadecafluorooctyl methacrylate (PDFOMA) as the functionality monomer. The pore properties and permeability could be tuned by the composition of the polymerization mixture. The characterization and evaluation results revealed that the obtained POSS–PDFOMA hybrid monolith owned the merits of POSS and PDFOMA with good mechanical stability, no residual silanol and high affinity to fluorous compounds. A series of perfluoroalkyl methacrylates were baseline resolved on the optimized monolithic column under isocratic elution of 70% acetonitrile aqueous solution. Such a resolution could not be achieved on a silica-based C18 monolithic column. A column efficiency of 30000N/m was observed. In addition, several perfluoroalkyl sulfonates were also baseline separated on the fluorous monolith applying 0.1% (v/v) acetic acid aqueous solution containing 75% acetonitrile as mobile phase without the addition of ammonium.

Hybridization of a Macroporous Sponge and Spherical Microporous Adsorbents for High Throughput Separation of Ionic Solutes

Hybrid materials using a macroporous sponge and spherical microporous adsorbents have been developed for an effective rapid pretreatment of water samples. Various adsorbents, including methacrylate series, divinylbenzene (DVB), and graphite particles, were utilized for hybridization with a macroporous sponge consisting of polyethylene and polyvinyl acetate, EVA resin. Both the EVA resin and each of the particles were thermally blended at 150°C with water-soluble pore templates, pentaerythritol and poly (oxyethylene, oxypropylene) triol. After molding as a columnar shape, the hybrid materials were observed by a scanning electron microscope both before and after washing with water/methanol sonication. Only methacrylate series could be effectively fixed onto the pore surface of sponge, whereas DVB and graphite particles were incorporated to the EVA matrix. We assume that the chemical interactions between EVA and adsorbents are very important for effective hybridization to fix the adsorbents onto the pore surface. Furthermore, we demonstrated the hybridization of ion-exchange resin and sponge for a high throughput purification of ionic compounds. The ion-exchangeable polymers prepared by methacrylic acid, 4-vinylpiridine, and p-styrene sulfonic acid with ethyleneglycol dimethacrylate could be fixed at a given ratio of "20, wt%", and its effective adsorption based on the ion-exchange ability was observed under rapid elution (3 mL min(-1)).

Stereospecific Free Radical and RAFT Polymerization of Bulky Silyl Methacrylates for Tacticity and Molecular Weight Controlled Poly(methacrylic acid)

A series of silyl methacrylates [CH2═C(CH3)CO2SiR3] with varying silyl group bulkiness [R3Si: Me3Si, Et3Si, Me2tBuSi, iPr3Si, Ph2tBuSi, Ph3Si, and (Me3Si)3Si] were synthesized and radically polymerized to efficiently give soluble polymers with the exception of the highly bulky tris(trimethylsilyl)silyl methacrylate (TTMSSMA), which resulted in insoluble polymers. All the polymers can easily be converted into poly(methacrylic acid) (PMAA) via acid- or fluoride-induced deprotection of the silyl groups and further into poly(methyl methacrylate) (PMMA) via methylation with trimethylsilyldiazomethane for the analysis of molecular weight and tacticity. The tacticity was dependent on the bulkiness of the silyl substituents; the isotacticity increased with increasing bulkiness. Thus, a series of PMAAs and PMMAs with various tacticities ranging from syndiotactic-rich (rr = 74%; Me2tBuSi) to atactic (mr = 50%; iPr3Si) and highly isotactic [mm = 93%; (Me3Si)3Si] enchainment were obtained by conventional radical poly...

Effect of the molecular architecture of side radicals on the optical properties of comb-shaped polymers

The optical properties of four comb-shaped polymers of the methacrylic series with different optically anisotropic groups in side chains are studied by the methods of flow birefringence and viscometry. The experimental values of the optical anisotropy are compared with theoretical estimates calculated in terms of the additivity principle of polarizabilities of valence bonds. It is shown the optical properties of comb-shaped polymers significantly depend on the position (even or odd) of optically anisotropic side groups relative to the main chain.