Hyperbranched Polyurethane Acrylate Research Articles

Synthesis of xylitol-based hyperbranched polyurethane acrylate and its application in self-matting acrylate coatings

Synthesis of xylitol-based hyperbranched polyurethane acrylate and its application in self-matting acrylate coatings

UV curable hyperbranched polyester polyurethane acrylate for hydraulic machinery coating

The content of river cement and sand in our country is relatively high, and the surface of hydraulic machinery in hydropower stations is often subject to fatigue damage and erosion. This topic is mainly used to solve the problem of abrasion and corrosion of hydraulic machinery coatings. UV curable polyurethane acrylate (PUA) can be quickly solidified into film and directly coated on the surface of hydraulic machinery with excellent anti-wear, adhesion properties and low cost. In this work, a hyperbranched polyester synthesized by the stepwise reaction of trimethylolpropane (TMP) and dimethylolpropionic acid (DMPA) was as a ‘nucleus’, and the polyurethane prepolymer was obtained by grafting IPDI and PTMG (C Schüll, H Frey, 2013 Grafting of hyperbranched polymers: from unusual complex polymer topologies to multivalent surface functionalization, Polymer, 54, 5443–5455). The UV-curing hyperbranched polyester polyurethane acrylate (PUA-1) was prepared by capping with HEA (Xu, W, Wang, W, Hao, L, Zhao, W, Liu, H, Wang, X 2020 Effect of generation number on properties of fluoroalkyl‐terminated hyperbranched polyurethane latexs and its films. J. Appl. Polym. Sci., e49215). Another UV-curing hyperbranched polyester polyurethane acrylate (PUA-2) was prepared as comparison by using TDI and PTMG as the main raw materials. Fourier Transform Infrared Spectrometer,1H-nuclear magnetic resonance spectroscopy, Gel Permeation Chromatography, thermogravimetric analysis and dynamic thermomechanical analysis were used to characterize its structure and properties. The wear rate of the two hyperbranched polyesters measured by the underwater steel ball method is below 3%, The swelling rate of PUA-1 is between 250%–300%, and the swelling rate of PUA-2 is around 260%, indicating that PUA-2 has better solvent resistance than PUA-1, and the internal structure of the film is more dense. TG analysis showed that the thermal stability of the two materials was good.

Development of a novel resin for provisional prostheses using hyperbranched polyurethane acrylate and triethylene glycol dimethacrylate - An in vitro study.

To develop a novel resin for provisional prostheses using hyperbranched polyurethane acrylate (HBPUA) and triethylene glycol dimethacrylate (TEGDMA) with promising mechanical properties and low volumetric shrinkage. Four groups including TIH3-0 (100 wt% TEGDMA), TIH3-30 (30 wt% HBPUA + 70 wt% TEGDMA), TIH3-60 (60 wt% HBPUA + 40 wt% TEGDMA), and TB-60 (60 wt% bisphenol A-glycidyl dimethacrylate + 40 wt% TEGDMA) were prepared and commercial Luxatemp (DMG) was used for comparison. Fourier transform infrared spectroscopy and gel permeation chromatography were used for material characterization. Mechanical properties including microhardness, flexural strength, flexural modulus, and load energy were measured before and after water immersion. Physical properties measurement included weight changes, solubility, water absorption, surface hydrophobicity, and volumetric shrinkage. Finally, biocompatibility was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The number- and weight-average molecular weights of the HBPUA were approximately 870 and 1480, respectively. The addition of HBPUA to TEGDMA increased the mechanical strength considerably. Although the weight changes and water absorption of TIH3-60 were higher than those of Luxatemp, the microhardness, flexural strength, flexural modulus, load energy, solubility, shrinkage, and biocompatibility of TIH3-60 were either comparable or superior to those of Luxatemp. Based on the findings of the present study, TIH3-60 has potential for development as a new provisional material.

Hyperbranched polyurethane acrylates synthesized via copolymerization of monomers A2 and B3 with monofunctional compound BR added gradually at different rates

AbstractA kinetic model was proposed to describe hyperbranched polymers (HBPs) formed by the polymerization of monomers A2 and B3 with monofunctional compound (BR) added gradually in a semibatch reactor. The dependences of the degree of polymerization (DP) and the degree of branching on the reaction time and the monomer compositions were calculated. The DP of the HBPs could be increased by the slow addition of BR in the reactor. If the monomers B3 and A2 were mixed at a molar ratio of B3:A2 = 1:3, and the BR was fed slowly into the reactor, the HBPs with weight average DP were approximately 3200 and 16 700 at conversion of 0.95 and 0.99, respectively, which were higher than those prepared by the batch system. This theory was further verified by an experimental demonstration. Hyperbranched polyurethane acrylate can be synthesized with a higher DP in a semibatch system than in a batch reactor.

Preparation and properties of UV-curable hyperbranched polyurethane acrylate hard coatings

In order to efficiently protect plastic cover of 5G mobile phones, a novel hyperbranched polyurethane acrylate-based hard coating (HBPUA) having highly rigid hyperbranched cores was prepared and used as the protective film. For purpose of researching the structure and property relationship, two more hyperbranched cores (Hyper-6OH) and corresponding HBPUA oligomers were also synthesized. The structures of Hyper-6OH and HBPUA were characterised by proton nuclear magnetic resonance, and the molecular weight of HBPUA was confirmed by gel permeation chromatography. To further enhance the crosslinking and lower the internal stress, pentaerythritol tetra(3-mercaptopropionate) (PETMP) was introduced into the film system. The curing behaviours of the prepared HBPUA coatings were determined by Fourier-transform infrared spectroscopy. The results indicated that the double bond conversion was associated with the rigidity of the hyperbranched core and the content of thiol groups. The properties of HBPUA-based films were characterized by the test of gel content, swelling ratio and water absorption and as well as dynamic mechanical property, mechanical property, thermogravimetry and surface property. The results reveal that the pencil hardness of the prepared coatings reaches 5H that is higher than the commercially available resin PUA-6, enabling potential application in the protection of plastic cover. The rigidity of the hyperbranched cores and the introduction of PETMP remarkably affect the Tg value of the films, and the addition of thiol groups increases the gel content, swelling ratio, toughness and adhesion of coatings, but decreases the water absorption and tensile strength. Moreover, all coatings exhibit good thermal properties.

Kinetic Model and Synthesis of Hyperbranched Polyurethane Acrylates from Monomers A2 and B3 with End-Capping Molecules BR

The preparation of hyperbranched polymers by the polymerization of monomers A2 and B3 with monofunctional monomers BR was investigated by recursive and kinetic models. A diagram of the gel and sol regions corresponding to the composition of the monomers was proposed. According to the kinetic model, the average degree of polymerization and the degree of branching (DB) that are dependent on the conversion and initial compositions of the reactants were calculated by a generating function method. If the molar ratio of B3/A2/BR was 1:3:3, then polymers with a weight-average degree of polymerization of 171 and a DB of 0.97 could be obtained at a conversion of 0.99. Polyurethane acrylates were further prepared from various mixtures of trimethylolpropane ethoxylate (B3), hexamethylene diisocyanate (A2), and hydroxyethyl acrylate (BR). The molecular weights of the polymers predicted by the model were in good agreement with those determined by gel permeation chromatography.

Castor oil-based waterborne hyperbranched polyurethane acrylate emulsion for UV-curable coatings with excellent chemical resistance and high hardness

Synthesis, characterization, and coating performance of castor oil (CO)-based waterborne hyperbranched polyurethane acrylate (WHPUA) emulsions are highlighted in this work. Herein, a second-generation CO-based hyperbranched polyester (C20) was synthesized by introducing the renewable CO as a B3 core and dimethylolpropionic acid as an AB2 monomer via a pseudo-one-pot condensation procedure. Three types of CO-based WHPUA emulsions were prepared through the addition of the hyperbranched C20 with maleic anhydride (MA) and the isocyanate-bearing semiadduct (IPDI-HEA) at different MA/IPDI-IH molar ratios without the addition of any emulsifiers. The prepared emulsions were further formulated into UV-curable coating formulations and exposed to a medium-pressure mercury lamp. Consequently, the obtained UV-cured coatings exhibited outstanding adhesion performance, excellent transparency, and an acceptable degree of final double bond conversion. Owing to a relatively low concentration of hydrophilic units and a large number of acrylate functionalities in the waterborne oligomer, the obtained films were endowed with high crosslinking density and low hydrophilic nature, thus producing enhanced tensile strength, pencil hardness, water resistance, and chemical resistance. Due to their combination of renewable materials, a waterborne system and a UV-curing technique, these CO-based WHPUA emulsions offer promising opportunities to be used as environmentally friendly coatings.

Synthesis and properties of UV-curable cardanol-based acrylate oligomers with cyclotriphosphazene core

Multiarm cardanol-based oligomers with a cyclotriphosphazene core were prepared through a nucleophilic substitution reaction; the structures of oligomers were fully characterized and confirmed through Fourier transfer infrared spectrometry, 1H nuclear magnetic resonance (NMR), 31P NMR, and gel permeation chromatography. The designed multiarm bio-based acrylates (AECC) were successfully prepared by epoxidizing the unsaturated aliphatic chain of cardanol segments with m-chloroperoxybenzoic acid and acrylating epoxy groups. The synthesized oligomers contain rigid phosphazene/benzene rings as “hard cores” and long aliphatic chains as “flexible shells.” Compared with commercial hyperbranched polyurethane acrylate (CN2302) and acrylated epoxidized soybean oil, cured AECC coatings and films exhibited not only greater hardness, excellent adhesion, higher glass transition temperatures, and excellent mechanical properties but also good thermal stability and biodegradability. We successfully obtained a high-performance UV-curing resin that has a high biorenewable material content and can meet basic daily requirements.

Effect of soft chain length and generation number on properties of flexible hyperbranched polyurethane acrylate and its UV-cured film

Abstract A series of UV-curable flexible hyperbranched polyurethane acrylate (F-HBPUA) with various generation numbers and soft chains are successfully developed by modifying different generations of hydroxyl terminated hyperbranched polyurethane (HBPU-OH) with diverse soft chains contained semiadduct urethane monoacrylate. The influence of generation number and soft chain on the performances of F-HBPUA and its UV-cured freestanding film is studied. The degree of branching of F-HBPUA from the second to the fifth generation is proved to be 0.74, 0.79, 0.82 and 0.94, respectively. The glass transition temperature of F-HBPUA increases with increasing generation number but it decreases with the increase of soft chain length. The thermal stability of F-HBPUA improveswith higher generations while the longer soft chain is only beneficial to the heat resistance at below 300 °C. As the increase of generation number and chain length, the UV-curing time of F-HBPUA film is significantly shortened from 12 s to 3 s, the flexibility of the UV-cured film is greatly increased from 4 mm to 1 mm, adhesion is improved to 3 grades. This novel flexible hyperbranched polyurethane acrylates can be applied to coatings, membranes and 3D print parts with excellent flexibility.

Preparation, Characterization and Application of UV-Curable Flexible Hyperbranched Polyurethane Acrylate.

A novel UV-curable hyperbranched polyurethane acrylate (FHBPUA) with excellent flexibility is successfully synthesized based on a reaction of hydroxyl terminated hyperbranched polyurethane (regarded as core) with flexible semiadduct urethane monoacrylate (regarded as arms). The structure and property of FHBPUA is firstly analyzed and then utilized as functional additives to ameliorate the UV-curing and mechanical properties of epoxy acrylate resin. The degree of branching of FHBPUA turns out to be 0.82. Its thermal decomposition process consists of three different stages, and the glass transition temperature is around 65 °C. The freestanding FHBPUA film (~30 μm thickness) can be UV-cured within 3 s, and its flexibility is up to 1 mm. With the increase of FHBPUA content to 10 wt %, the UV-curing time of UV1000 film decreases from 6 to 3 s, flexibility strikingly increases from 10 to 1 mm, and adhesive force also improves from 5 to 3 grades, meanwhile its glossiness is not influenced by FHBPUA. In addition, a certain amount of FHBPUA can improve the tensile strength and elongation at break of UV1000 film. This novel FHBPUA can be used not only to develop flexible UV-curable freestanding films but also as functional additives to perfect other UV-curable compositions like coatings, inks and 3D printed parts.

Modification and characterization of urethane acrylate oligomers used for UV-curable coatings

Nine modified urethane acrylate oligomers including polyether-modified polyurethane acrylate, epoxy-modified polyurethane acrylate and hyperbranched polyurethane acrylate have successfully been synthesized and characterized by Fourier transform infrared spectra. The properties of UV-cured films formed by these oligomers were also investigated. The effects of the molecular structure of the oligomers on the properties of cured film, including tack-free time, pencil hardness, impact resistance, adhesion and boiling water resistance, have been discussed. The results indicate that the UV-cured film with good performance can be designed by the modification of the molecular structure of the oligomer. Among the oligomers prepared in this paper, the cured film formed using HBPUA-50%OA as oligomer exhibits a relatively short tack-free time, high hardness, good impact resistance, great adhesion and boiling water resistance.

Synthesis of UV-Cured Hyperbranched Polyurethane Acrylate Coatings and Its Corrosion Resistance Revealed by Electrochemistry

Synthesis of UV-Cured Hyperbranched Polyurethane Acrylate Coatings and Its Corrosion Resistance Revealed by Electrochemistry

UV-curable coating crosslinked by a novel hyperbranched polyurethane acrylate with excellent mechanical properties and hardness

A novel hyperbranched polyurethane acrylate was synthesized. It was used as crosslinker to prepare a series of high-performance UV-curable coatings.

Synthesis of Novel Hyperbranched Polyurethane Acrylate Based on Pentaerythritol

To study the structure and properties of hyperbranched polyesters as well as the modified ones. Three generations of hyperbranched polyesters named HBPE-1, HBPE-2 and HBPE-3 were synthesized by the reactions from pentaerythritol and 2,2-dihydroxy-methyl-propionic acid by single-step polycondensation. They were characterized by 1H NMR, 13C NMR and the results indicated they possessed a high degree of branching. Then homemade urethane acrylate prepolymer reacted with three generations of hydroxyl-terminated hyperbranched polyesters introducing C=C contents, the product was characterized by FT-IR, DSC, TGA techniques. The results of TGA showed well thermal stability of all the products. TGA curves of the modified HBPES showed two stages, 280-350°C means pyrolysis of main chain ester section and 400-450°C means pyrolysis of urethane acrylate section. The results of DSC indicated that glass transition temperature increased with the number of the hyperbranched polyester units’ increment. What’s more, glass transition temperature of HBPE-3 was 48.13°C. HPUA-3 was semi-crystalline material, its glass transition temperature was-12.59°C, cold crystallization temperature Tc 110.92°C, melting temperature Tm 134.74°C. Since the introduction of a large number of unsaturated units to the end, the resin can be introduced into the UV-curable systems for paints, inks, adhesives and some other fields.

Application of Thiol-ene “click” Chemistry to Preparation of Hyperbranched Polyurethane Acrylate Oligomers Containing Carboxyl Groups

Application of Thiol-ene “click” Chemistry to Preparation of Hyperbranched Polyurethane Acrylate Oligomers Containing Carboxyl Groups

The Production of Green Polymer - Hyperbranched Curable Palm Oil Oleic Acid

Palm oil is one of the main raw materials available in the country. Hence, the diversification ofpalm oil derivatives into new products has been given priority. The development of new radiation curable materials for applications in radiation ultraviolet (UV) or electron beam (EB) curing technology is an important research area. The hyperbranched curable polyurethane acrylate (HBPUA) from oleic acid of palm oil has been synthesized through a three-step reaction. Dipentaerythritol was initially reacted with 2, 2-bis (hydroxymethyl) propionic acid in a solution medium aided by p-toluene sulfonic acid as a catalyst to form hyperbranched polyol polyester first generation (HBP-1). HBP-1 then used as the core and reacted with palm oil oleic acid to form the hyperbranched polyol polyester second generation (HBP-2). HBPUA was prepared by reacting HBP-2 resin with diisocyanate and hydroxyl-containing acrylate monomer with the presence of 0.1-2 wt% dibutyltin dilaurate as a catalyst. The reaction was confirmed by several analytical data namely hydroxyl value (OHV), fourier transform infrared (FTIR), gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) analyses. The HBPUA was easily curable when subjected to EB radiation. The thermal decomposition of HBPUA showed good thermal stability up to 450 oC.

Optimization of Blue Light Induced Hyperbranched Polyurethane Acrylate System Applied to Textiles

The introduction of blue light curing to dyeing and finishing will be save energy and reduce emission. Searching out blue light cured polymers of high strength and good flexibility is immediately needed. Hyperbranched polyurethane acrylate (HBPUA) exhibits relatively low viscosity and good mechanical property. Typical acrylate monomers of low smell were copolymerized with HBPUA, subsequently, the tensile mechanical property and flexibility of blue light cured polymers were evaluated in contrast of commercial adhesives. The concentration of monomer was further optimized and the dynamic mechanical property of selected film was presented. The results show that 80/20 HBPUA/TPGDA copolymer is thought of the most suitable system for textiles in this study. The related character of 80/20 HBPUA/TPGDA blue light cured system is listed below: 52.3% reaction conversion, 7.2MPa tensile stress, 9.2% fracture elongation, 61.8°C glass transition temperature.

Synthesis of EB-curable hyperbranched urethane acrylate from palm oil oleic acid

Hyperbranched urethane acrylate (HBPUA) from oleic acid of palm oil has been synthesised by a three-step reaction. Dipentaerythritol was initially reacted with 2, 2-bis (hydroxymethyl) propionic acid in a solution medium aided by p-toluene sulfonic acid as the catalyst. This mixture was then used as the core (HBP) and reacted with palm oil oleic acid to form the hyperbranched polyol (HBP-1). The hyperbranched polyurethane acrylate (HBPUA) was prepared by reacting HBP-1 resin with diisocyanate and hydroxyl-containing acrylate monomer in the presence of 0.1–2 wt% dibutyltin dilaurate as a catalyst. The reaction was confirmed by several analyses, i.e., determination of hydroxyl value (OHV), Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) spectroscopy analyses. HBPUA was found curable when subjected to electron beam (EB) irradiation. The thermal stability of EB cured films of HBPUAs was determined by thermogravimetric analyser (TGA). The thermal decomposition of HBPUAs showed good thermal stability up to 450°C.

Synthesis of UV-curable hyperbranched polyurethane (meth)acrylate oligomers via thiol-ene “click” chemistry

First, the second-generation hyperbranched poly(amine-ester) (G2-OH) was successfully prepared by thiol-ene “click” chemistry. Subsequently, a series of photosensitive hyperbranched oligomers (G2-ORs) were synthesized by facile modifications of the G2-OH with acryloyl chloride, methacryloyl chloride, IPDI-HEA, and IPDI-HEMA, respectively. The structures of hyperbranched oligomers were characterized by element analysis, FT-IR, 1H NMR, GPC and viscosity measurement. It was shown that these synthesized oligomers have narrow molecular weight distribution and low intrinsic viscosity at 30°C. UV–vis spectra results showed that the G2-ORs had sharp absorption bands at around 202 nm. The results of photosensitivities measurement indicated that the G2-Macr shows the highest photosensitive than other hyperbranched oligomers in the absence of photoinitiator. In addition, these UV-cured photosensitive G2-ORs had good thermal properties. The solubilities of the synthesized hyperbranched oligomers were also examined. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Steady rheological behaviors of UV-curable waterborne hyperbranched polyurethane acrylate dispersions

A rotational rheometer was used to investigate the steady rheological behaviors of UV-curable waterborne hyperbranched polyurethane acrylate dispersions (WHBPUADs). The flow curves of WHBPUADs were fitted mathematically using the Cross model. The effects of many factors including solid content, concentration of hydrophilic groups, and degree of neutralization on the rheological behaviors were studied and discussed. It was found that the viscosity of WHBPUAD decreased with increasing shear rate, indicating that WHBPUAD was pseudoplastic. On the other hand, at the same shear rate, the viscosity of WHBPUAD increased with increasing solid content and degree of neutralization but decreased with increasing concentration of hydrophilic groups. The Cross model could describe the flow curve of WHBPUAD accurately, with square of correlation coefficient (R 2) above 0.9. Moreover, most of the zero-shear viscosity values (η 0) obtained by the Cross model were located in the range of 0.2–10 Pa·s, which could fully meet the practical application requirement.