Series Of Acrylates Research Articles

Synthesis and characterization of ureidopyrimidinone-functionalized polyurethane acrylates and their hybrid nanocomposites for UV coating applications

In this study, ureidopyrimidinone moieties (UPy), capable of physical crosslinking via quadruple hydrogen bonding, were successfully incorporated into UV-curable polyurethane acrylate prepolymers. First, a hydroxyl-terminated unsaturated ester monomer was synthesized and reacted with isophorone diisocyanate to create a hydroxyl-terminated UV-curable urethane oligomer (U–OH). Then, isocyanate-terminated building blocks (UPy moieties and an acrylate-based photosensitive monomer) were synthesized and used in various ratios to functionalize U–OH for the preparation of a series of UV-curable UPy-containing polyurethane acrylate (PUA) resins. The resulting products were structurally characterized using 1H NMR and FTIR spectroscopy. Furthermore, organic–inorganic hybrid nanocomposites were obtained by introducing silane coupling agents into PUA resins using the sol–gel process. A series of UV-curable UPy-containing PUA coatings and hybrid nanocomposites were prepared, and their synergistic effect on coating properties was investigated. The dynamic mechanical analysis revealed that the Tg of the samples increased with increasing UPy content, although the mechanical properties remained largely unaltered, as shown by the stress–strain test. The studies also demonstrated that the hybrid nanocomposites exhibited higher decomposition temperatures and better thermal stability compared to pure PUAs. All the coatings exhibited good transparency in the visible region. An optical microscope was used to investigate the self-healing property by scratching the plexiglass panels with a razor blade. Among the other samples, the coating with the highest percentage of UPy content exhibited the best self-healing ability after heat treatment at 90 °C for 10 min.Graphical abstract

Photo Fenton RAFT Polymerization of (Meth)Acrylates in DMSO Sensitized by Methylene Blue.

A novel open-to-air photo RAFT polymerization of a series of acrylate and methacrylate monomers mediated by matching chain transfer agent irradiated by far-red light in DMSO is reported. Hydroxyl radical (•OH) generated from methylene blue (MB) sensitized decomposition of H2 O2 via photo-Fenton like-reaction is used for polymerization initiation. The "living/control" characteristic is evidenced by kinetic study, in which a pseudo first order curve and linearly increases of molecular weight with the increase of monomer conversion are observed. The living end-group fidelity is characterized by MALDI-TOF-MS and 1 H NMR results, and confirmed by successful chain extension. The temporary controllability is proved by light on/off switch experiment. This article is protected by copyright. All rights reserved.

Biomimetic high water adhesion superhydrophobic surface via UV nanoimprint lithography

Imitating nature and comprehending its workings is a means for human beings to advance the development of functional materials. In this study, UV nanoimprint lithography technology was utilized to successfully replicate the micro-nano hierarchical structure (micro-papillae and nano-wax tube crystals) present on the surface of the natural fresh lotus leaf. A series of UV-curable waterborne polyurethane acrylate (UV-WPUA) surfaces with special wetting and superhydrophobic properties were obtained. The polydimethylsiloxane negative stamp with lotus leaf’s structure was obtained through a stamp replica molding method, and then the UV-WPUA resin covered with the negative stamp was exposed to 172 nm Xe2* excimer and medium-pressure mercury lamps to mimic the micro-nano hierarchical structure of the lotus leaf. The UV-WPUA surfaces displayed high water adhesion superhydrophobic properties, with a water contact angle reaching 160.8° and water adhesive force of 140.0 μN, and exhibiting excellent self-cleaning performance. The results indicate that higher the UV intensity, the more accurately the surface replicates the micro-nano hierarchical structure of the lotus leaf, resulting in larger water contact angle and higher adhesive force. This study paves the way for the advancement of functional surfaces through the simulation of natural materials.

Effects of carbon chain length of acrylate monomer on sizing properties of sesbania gum-g-polyacrylate

A series of acrylate monomers with different carbon chain lengths including methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA) and 2-ethylhexyl acrylate (EHA) has been grafted onto molecular chains of native sesbania gum (SG) to obtain SG-g-polyacrylate with similar grafting ratios through Fenton’s initiator respectively. Effects of carbon chain length of the series of acrylates on sizing properties of the grafted SG on polyester yarn have been studied. It is found that, by grafting acrylates onto the molecular chains of SG, its sizing properties are improved markedly. Under the condition of similar grafting ratios, SG-g-PMA shows the highest apparent viscosity, tenacity of sizing film, wettability and adhesion strength to polyester fibre in all the grafted SG prepared. SG-g-PEA and SG-g-PEHA show the highest wear resistance and elongation of sizing film respectively. The polyester/cotton (65/35) warp yarns sized by SG-g-PMA, SG-g-PEHA and SG-g-PEA possess the highest tensile strength, tensile elongation and abrasion resistance respectively, in all the sized conditions. The SG grafted with acrylate monomers with different carbon chain lengths can meet various requirements in sizing polyester yarn.

Photochemically Driven Polymeric Biocompatible and Antimicrobial Thiol-Acrylate Nanocomposite Suitable for Dental Restoration.

The development a photochemically driven polymeric composite for dental restorative materials to restore tooth cavities with antibacterial, biocompatibility, and outstanding mechanical properties is an urgent need for clinical application in stomatology. Herein, a series of polyurethane acrylate (PUA) prepolymers and antibacterial polyurethane acrylate quaternary ammonium salts (PUAQASs) were synthesized, and their mechanical and biological properties were explored. The unique secondary mercaptan with a long shelf life and low odor was used to reduce oxygen inhibition and increase cross-linking density; meanwhile, modified photocurable nano zirconia (nano ZrO2) enhances mechanical properties of the nanocomposites and possesses preeminent dispersion in the matrix. The results show that minimal inhibitory concentrations (MICs) of PUAQASs are 200 and 800 μg/mL for Staphylococcus aureus and Escherichia coli, respectively. The addition of secondary thiols significantly increases the photopolymerization rate and monomer conversion. The highest hardness and modulus reach 1.8 and 8.7 GPa compared to 1.8 and 8.3 GPa for commercial resin. The lap shear stress on the pig bone is 912 MPa, and that on commercial resin is 921 MPa. Most importantly, the photochemically driven polymeric composite has excellent biocompatibility and significantly better antimicrobial properties than commonly used commercial resins.

Synthesis and Properties of Self-Polishing Antifouling Coatings Based on BIT-Acrylate Resins

Painting antifouling coatings is one of the most important methods to prevent marine biofouling. Acrylic resin is widely used in marine antifouling because of its excellent stickiness, water resistance, and film-forming capabilities. At present, the widely used acrylate antifouling coatings require a high concentration of cuprous oxide as antifoulant. The release and accumulation of copper ions are the main factors affecting the marine environment. In this study, BIT–allyl methacrylate (BM) and zinc acrylate (ZM) were selected as functional monomers copolymerized with methyl methacrylate (MMA) and butyl acrylate (BA) to prepare a series of BIT acrylate antifouling resins. The inhibitory effects of all resins against marine bacteria (S. aureus, V. coralliilyticus, and V. parahaemolyticus), marine algae (Chlorella, I. galbana, and C. curvisetus), and barnacle larvae were studied. Moreover, marine field tests on the BIT modified resin in coastal waters were conducted. The results demonstrate that the grafted BIT–zinc acrylate resin not only exhibits excellent antifouling properties but also a significant self-polishing performance, providing a novel strategy to design a long-term antifouling resin with stable antifoulant release.

Effects of Carbon Chain Length of Acrylate Monomer on Sizing Properties of Locust Bean Gum-g-P (AA-co-Acrylate)

In order to impart good application properties to locust bean gum size for all-polyester yarn, a series of acrylate monomers including methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and common hydrophilic monomer–acrylic acid were grafted onto molecular chains of native locust bean gum to obtain locust bean gum- g-P(AA-co-acrylate) products with similar grafting ratios through Fenton’s reagent, respectively. The effects of carbon chain length of the series of acrylates on sizing properties of the grafted locust bean gum for polyester warp were studied. It was found that by grafting acrylates onto the molecular chains of locust bean gum the sizing properties of the locust bean gum were improved markedly. Under the condition of similar grafting ratios, locust bean gum- g-poly(AA-co-methyl acrylate) showed the highest apparent viscosity, water solubility, film strength, wettability, and adhesion to polyester fiber in all the grafted locust bean gum prepared. Meanwhile, locust bean gum- g-poly(AA-co-butyl acrylate) and locust bean gum- g-poly(AA-co-2-ethylhexyl acrylate) had the highest wear resistance and elongation of sizing film, respectively. The modified locust bean gum grafted with acrylate monomers with different carbon chain lengths was able to meet various requirements in the sizing process for polyester yarn.

The structure of the kidneys and their intra- and extra-organ vascularization in poultry

The purpose of the study is to study the structural features of the kidneys and the sources of their vascularization in poultry. To study the structures of the kidneys, the method of conventional and fine dissection was used. In the manufacture of angiosteotopic preparations of the arterial system, self-hardening plastic of the acrylic series "Belakryl" was used. The objects of the study were the carcasses of chicken cross Hisex white, Peking duck and Italian goose at 160 days of age, in the amount of 9 pieces. Peking duck and Italian goose have cranial, middle, and caudal lobes in their kidneys, with the exception of chicken, which has an additional lobe. The relative mass of kidneys to body weight is 0.52% for chicken, 0.36% for Peking duck and 0.29% for Italian goose. The length of the kidneys from the length of the pelvis is 61.7% in the chicken, which is associated with a short trapezoid shape of the pelvic bone, in the Peking duck - 55.8% and in the Italian goose - 58.5%, which have long pelvic bones with their adaptation to the water image life. The kidneys maintain a constant osmotic pressure, chemical composition and active reaction of the blood by excreting excess salts and acidic products. The kidney parenchyma of the studied bird species consists of interstitial tissue, in which there are afferent renal arteries that produce urine and efferent ones that participate in the trophic function. The physiological functioning of the kidneys is associated with the work of the arterial system, which is involved in the excretory function. Arterial blood enters the kidneys through the cranial, middle, and caudal renal arteries. Within the kidney, the arteries branch into intralobular arteries. From which afferent arterioles depart, bringing blood to the vascular glomerulus. Efferent arterioles leave the vascular glomerulus, pass into the capillary and connect with the venous capillaries of the portal system of the kidneys.

Blood supply of the heart myocardium of the Edilbaev sheep breed

Pathologies of the cardiovascular system are a serious disease in diseases of small ruminants. The study of the anatomical and topographic coverage of the blood supply to the heart in various species and breeds allows expanding the field of knowledge in humane and veterinary cardiac surgery. The purpose of our study is to establish the features of anatomical and topographic disorders of the course and branching of the coronary vessels of the heart of sheep of the еdilbaevskaya breed, as well as to give them a morphometric characteristic.Sheep of the еdilbaevskaya breed at the age of twelve months, obtained during slaughter from the farm "Slaughterhouse" of the Leningrad Region of the Russian Federation and delivered to the Department of Animal Anatomy of the SPbGUVM, were used as cadaver material. As a technique for studying vasoradiography and manufacturing corrosion preparations using non-shrinking plastics of bulk acrylic series. According to the results of the study, it was found that the sheep of the еdilbaev breed have a left-coronal type of blood supply to the heart. Diseases of the heart and branches of the left and right coronary arteries of the heart were determined, and their morphometric characteristics were given.

Effect of side-group structure and temperature on chain transfer to polymer and branching in acrylate homopolymerizations

The paper reports studies of the effects of ester side-group size and structure on chain transfer to polymer (CTP) and mol% branches (%br) in the final polymers from monomer-starved semi-batch emulsion homopolymerizations of a series of alkyl acrylates with different numbers of ester OR side-group carbon atoms (NsgC) in the range 1–10. Although the high instantaneous conversions and high gel contents in the final polymers show that intermolecular CTP is significant, the kinetics have been analysed principally in terms of intramolecular CTP (intraCTP) because this is expected to be numerically the dominant CTP process. For linear OR side groups, there is a small, continuous increase in %br (from ~ 3.4 to ~ 5.0 mol%) as NsgC increases from 1 to 8, which arises predominantly from the acrylate molar mass (Macrylate) reducing the molar monomer concentration and from the small increase in rate coefficient for propagation (kp) as NsgC increases; no discernible effects of NsgC on the rate coefficient for intraCTP ({k}_{mathrm{trP}}^{mathrm{intra}}) are evident. For isomeric butyl acrylates, there is no measurable effect of isomer structure on %br (4.3–4.4 mol%), indicating that butyl groups are too small for changes in side-group bulkiness to influence {k}_{mathrm{trP}}^{mathrm{intra}} and kp. A similar observation was made for n-hexyl acrylate (nHA) and 2-ethylbutyl acrylate (%br 4.7–4.8 mol%). However, cyclohexyl acrylate (cHA) gives a much higher %br (~ 7.2 mol%), which has been assigned to steric effects increasing {k}_{mathrm{trP}}^{mathrm{intra}} because kp values for nHA and cHA are very similar. For OR side-groups with NsgC of 8 and10, there is a strong effect of side-group non-linearity (2-ethylhexyl, iso-octyl and iso-decyl) increasing %br, with polymers from n-alkyl acrylates having much lower %br (~ 4.5–5.0 mol%) than those from the equivalent non-linear acrylates (~ 6.7–7.1 mol%); since the kp values are expected to be similar for these acrylates, it is evident that the much bulkier non-linear OR groups cause a significant increase in {k}_{mathrm{trP}}^{mathrm{intra}} compared to the linear equivalents. Tentative hypotheses for these steric effects have been postulated. Studies of the effect of temperature (0–80 °C) on CTP and %br for methyl acrylate solution homopolymerization (in which intraCTP should be completely dominant) show the expected reduction in %br as temperature reduces, such that CTP is negligible at 0 °C; Arrhenius analysis gives an activation energy of 40.7 kJ mol−1 for intraCTP, which is within the range of values reported for n-butyl acrylate.

Studying the Influence of Mica Particle Size on the Properties of Epoxy Acrylate/Mica Composite Coatings through Reducing Mica Particle Size by the Ball-Milled Method

In this work, a series of epoxy acrylate (EA)/mica composite coatings were synthesized through introducing mica powders of different particle size into epoxy acrylate coatings and using an ultraviolet (UV) curing technique to investigate the influence of mica particle size on the coatings. Mica powders of different particle sizes were obtained by ball-milling for 4, 8, 12, 16, and 20 h with a planetary high-energy ball mill. The particle size and morphologies of ball-milled mica powders were characterized by laser particle size analyzer and scanning electron microscopy (SEM). The results indicated that planetary ball-milling reduced the particle size of mica powders effectively. Mica powders that were un-ball-milled and ball-milled were added into the epoxy acrylate matrix by a blending method to synthesize the organic-inorganic UV curable coatings. The optical photographs of the coatings showed greater stability of liquid mixtures with smaller particle size fillers. The chemical structures of EA/mica composite coatings were investigated by Fourier transform infrared spectroscopy (FTIR), and the conversion rate of C=C bonds was calculated. The results indicated that the C=C conversion of coatings with mica powders of smaller particle sizes was higher. Tests of mechanical properties and tests using electrochemical impedance spectroscopy (EIS) showed that pencil hardness, impact resistance, and coating resistance were improved due to the reduction of mica powders particle size.

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 °.

Synthesis of zwitterionic polymer and its application in textile stiffening finish

AbstractDevelopment of formaldehyde‐free stiffening finish agents is highly desirable in modern environmental‐friendly textile chemical processing technologies. Herein, two zwitterionic monomers are synthesized and used to synthesize a series of acrylate soap‐free emulsions. The prepared acrylate soap‐free emulsion was analyzed by nanoparticle size analyzer to determine grain size and PDI. The properties of polymer film obtained from emulsion were characterized by IR, DSC, and DMA. The results showed that zwitterionic monomer in acrylate emulsion can greatly improve the glass transition temperature (Tg) and initial tensile modulus of polymer film, and that ambient temperature had little effect on initial tensile modulus. It was found that when the amount of zwitterionic monomer is 3% of the total monomer dosage, the synthesized polymer emulsion can achieve the same stiffening effect as that of commercial stiffening agents. Meanwhile, the stiffness of finished fabric is less affected by the change in ambient temperature. The effective Tg increase and high initial tensile modulus of these zwitterionic polymers demonstrate their applicability in stiffening finish for seat belts.

Free radical polymerization of acrylates bearing acetylene for preparation of clickable polymers

It is still a challenge to directly, without any control means, synthesize polymers bearing acetylene groups by normal free radical polymerization (FRP) of acetylenyl vinyl monomers, such as propargyl (meth)acrylates, because the reactive acetylene groups result in chain branching and gelation. Some propargyl acrylates with alkyl substitutes, however, can afford linear and soluble polymers. To clarify the substitute effects the FRP behaviours of a series of acrylates bearing acetylene groups with or without substitutes are studied. Homopolymerizations of acetylenyl acrylates without or with mono-substitute on propargyl led to branched polymers at early reaction stage, and became gelled after 0.5 h with monomer conversion over 12% and gel content over 50%. The acetylenyl acrylates with di-substitutes on propargyl can afford linear and soluble homo- and copolymers with‾Mn up to over 10,000 and with 45–75% monomer conversion, except for monomer 2-(2-methylbut-3-yn-2-yloxy)ethyl acrylate (DMPOEA) which has di-substitutes and a spacer connecting to the propargyl. Reactivities of vinyl and acetylene groups were found within 20 times difference by laser flash photolysis (LFP) experiments. The substitute effects of acetylenyl acrylates on FRP are explained by the intramolecular cycloaddition between CC and CC to form lactone from the s-cis conformers of the di-alkyl substituted acetylenyl acrylates. Propagating radicals can transform to stable allyl radicals by α-H atom transfer and thus the chain propagations stop. Both real-time FT-IR monitoring of photo-polymerization and high resolution 13C NMR spectra of the polymer confirmed the existence of lactone units on polymer chains. The hypothesis is also accordance with facts obsorved in the FRP. Finally postpolymerization modification through acetylene groups on polymer chains by photo thiol-yne click reaction is exemplified.

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.

Research on the Performance of Series Waterborne Polyurethane Acrylate Modified Epoxy Acrylates

In this study, a series of bifunctional-based UV curable waterborne polyurethane acrylate modified epoxy acrylate (UV-WPUA) was prepared by using 2,4-toluene diisocyanate (TDI), Epoxy resin (E51) and polyethylene glycol (PEG) as the main materials. Waterborne resin and UV curing film with content of C-O-C were obtained by using polyethylene glycols with different molecular weights. The infrared spectra (FT-IR) demonstrated the presence of C=C and epoxy bond in the UV curing film chains. In addition, the molecular weight of the oligomer, and glass transition temperature, gelation rate and thermogravimetric analysis of the films were investigated.

Silica bonded N-(propylcarbamoyl)sulfamic acid (SBPCSA) as a highly efficient and recyclable solid catalyst for the synthesis of Benzylidene Acrylate derivatives: Docking and reverse docking integrated approach of network pharmacology

A green approach has been developed for the synthesis of a series of benzylidene acrylate 3(a-p) from differently substituted aromatic/heterocyclic aldehydes and ethyl cyanoacetate in excellent yields (90–98%), and employing silica bonded N-(Propylcarbamoyl)sulfamic acid as a recyclable catalyst under solvent-free condition. The molecular structure of compounds 3b, 3d and 3i were well supported by single-crystal X-ray crystallographic analysis. The present protocol bears wide substrate tolerance and is believed to be more practical, efficient, eco-friendly, and compatible as compared to existing methods. In-silico approaches were implemented to find the biochemical and physiological effects, toxicity, and biological profiles of the synthesized compounds to determine the expected biological nature and confirm a drug-like compound. A molecular docking study of the expected biologically active compound was performed to know the hypothetically binding mode with the receptor. Also, reverse docking is applied to recognize receptors from unknown protein targets for drug-like compounds to explain poly-pharmacology and binding postures with different receptors.

Semiconductor Quantum Dots Are Efficient and Recyclable Photocatalysts for Aqueous PET-RAFT Polymerization.

This Letter describes the use of CdSe quantum dots (QDs) as photocatalysts for photoinduced electron transfer reversible addition-fragmentation chain transfer (PET-RAFT) polymerization of a series of aqueous acrylamides and acrylates. The high colloidal solubility and photostability of these QDs allowed polymerization to occur with high efficiency (>90% conversion in 2.5 h), low dispersity (PDI < 1.1), and ultralow catalyst loading (<0.5 ppm). The use of protein concentrators enabled the removal of the photocatalyst from the polymer and monomer with tolerable metal contamination (8.41 ug/g). These isolated QDs could be recycled for four separate polymerizations without a significant decrease in efficiency. By changing the pore size of the protein concentrators, the QDs and polymer could be separated from the remaining monomer, allowing for the synthesis of block copolymers using a single batch of QDs with minimal purification steps and demonstrating the fidelity of chain ends.

Synthesis of non-isocyanate polyurethanes and their application in radiation-curable aerospace coatings

Although the current polyurethane coatings used in the aerospace applications meet the stringent performance requirements, they don’t comply with the environmental demands, e.g., low VOC contents. Moreover, containing a significant amount of solvent, they usually need long drying times, which causes significant production burdens. Furthermore, many of these coatings contain isocyanates, which are hazardous and are likely to be regulated soon.In this study, a series of sustainable UV-curable non-isocyanate urethane acrylate (NIPU-AC) oligomers, with different structures and acrylate equivalent weights, were synthesized and used as a primary building block of UV-curable coatings for aerospace applications. Synthesis of the NIPU-AC oligomers was carried out in three steps: First, multi-functional cyclic carbonates (MFCC) were prepared by carbonation of aliphatic epoxy compounds under mild temperature and pressure conditions in the presence of a catalyst. In the next step, amine-terminated polyurethane oligomers (PUPAs) were synthesized by the reaction of MFCCs with a stoichiometric excess amount of aliphatic and cycloaliphatic amines. (meth)acrylate functionality was then introduced by direct reaction of amine groups at the chain ends of PUPAs with methacrylic anhydride (MAAH). The amine value titration and FTIR confirmed the successful synthesis of NIPU-AC oligomers with >95% yield. Finally, UV-curable NIPU coatings, as a new generation of sustainable coatings for aerospace applications, were developed and evaluated for aerospace-critical performance properties, such as low-temperature flexibility and resistance to specific chemicals/fluids.The results showed that flexibility at -54 ℃ (no cracks or delamination at 1/8”), and good chemical resistance (MEK double rubs > 90, and no significant change in the appearance regarding the fluids) could be reached through the proper design of NIPU-ACs, selection of appropriate reactive diluents, and UV-cure conditions. These fast-curable NIPU coatings, which contain low VOCs and HAPS and no isocyanates, could be sustainable alternatives for current aerospace polyurethane coatings.

UV‐curable polyurethane acrylate resin containing multiple active terminal groups for enhanced mechanical properties

ABSTRACTIn this article, aiming to develop the high performance ultraviolet (UV)‐curable resin used in the polymer matrix composite, a series of polyurethane acrylate (PUA) resins with the different numbers of allyl terminal groups were elaborately designed and synthesized, in which the contents of hard segments and soft segments were also adjusted simultaneously. The effects of allyl number on properties of PUA were systemically investigated. It was found that allyl number had the negligible effect on the processability as well as positive effect on thermal performances, and all PUA resins exhibited the low viscosity and rapid UV polymerization. Besides, with the change of allyl number in the range of 2–4, PUA resin casting with three allyls possessed the preferable mechanical properties such as 85.1 MPa tensile strength, 3.94 GPa tensile modulus, and 20.7 kJ m−2 impact strength. More importantly, the high strength and high modulus of the composite further demonstrated the wide potentials of the as‐prepared PUA resin as the ideal resin matrix candidate for the fiber reinforced polymer composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48147.