Acrylic Content Research Articles

Development of a methodology for the study of polymer wound coatings for application characteristics

This paper reports a research methodology for characterizing wound dressings in order to assess the application properties of medical devices as a whole. Wound dressing was based on grafting polymerization of N-vinyl caprolactam and 2-hydoxyethyl acrylate on polyvinyl alcohol. The obtained copolymer was characterized by FTIR. Cross-linked films of wound dressings were obtained by radiation treatment of the copolymers. The physico-mechemical properties of wound dressings were investigated. Testing included degree of swelling, elastic modulus, tensile strength and elongation at break. The radiation doses of the reaction affected physico-mechanical properties of wound dressings. As the dose of radiation increased, the yield of gel increased, degree of swilling and tensile strength decreased. Also, the results indicated that the yield of the crosslinked fraction increases, and the swelling capacity of polymer mesh decreases with increasing 2-hydroxyethyl acrylate content in the graft copolymer

Design and development of a reinforced tubular electrospun construct for the repair of ruptures of deep flexor tendons

This research aims at developing a more potent solution for deep flexor tendon repair by combining a mechanical and biological approach. A reinforced, multi-layered electrospun tubular construct is developed, composed of three layers: an inner electrospun layer containing an anti-inflammatory component (Naproxen), a middle layer of braided monofilament as reinforcement and an outer electrospun layer containing an anti-adhesion component (hyaluronic acid, HA). In a first step, a novel acrylate endcapped urethane-based precursor (AUP) is developed and characterized by measuring molar mass, acrylate content and thermo-stability. The AUP material is benchmarked against commercially available poly(ε-caprolactone) (PCL). Next, the materials are processed into multi-layered, tubular constructs with bio-active components (Naproxen and HA) using electrospinning. In vitro assays using human fibroblasts show that incorporation of the bio-active components is successful and not-cytotoxic. Moreover, tensile testing using ex vivo sheep tendons prove that the developed multi-layered constructs fulfill the required strength for tendon repair (i.e. 2.79–3.98 MPa), with an ultimate strength of 8.56 ± 1.92 MPa and 8.36 ± 0.57 MPa for PCL and AUP/PCL constructs respectively. In conclusion, by combining a mechanical approach (improved mechanical properties) with the incorporation of bio-active compounds (biological approach), this solution shows its potential for application in deep flexor tendon repair.

Data Envelopment Analysis and Decision Maker Models: An Innovative Approach for Optimization of Reaction Variables of Graft Copolymerization of Poly(butyl acrylate) to Tamarind Seed Xyloglucan

AbstractThis article presents a novel methodology using a combination of non‐parametric frontier analysis models, data envelopment analysis (DEA), and decision maker (DM) model to optimize real‐time reaction variables, that is, concentration of butyl acrylate, time duration of the reaction, and temperature for precision synthesis of poly(butyl acrylate) (PBA) and xyloglucan (tamarind seed polysaccharide) graft copolymers.The copolymer samples (units) obtained by a different set of reaction variables and conditions are ranked using DEA to identify the efficient units. An appropriate minimum weight restriction is imposed by the DM on the chosen inputs and output by linear programming models that are designed in such a way that each DEA efficient unit can get “maximin” weight. The model predictions for reaction parameters and experimental data obtained are found to be very close to each other.

ION BEAM INDUCED MODIFICATION OF THE PET ION-TRACK MEMBRANES SURFACE WITH FUNCTIONAL MONOMERS

This study considers the possibility of using high-energy electrons (3.8 MeV, dose range of 46–200 kGy) for radiation-induced grafting of the polyethylene terephthalate ion-track membranes (PET ITMs) with the functional monomer of acrylic acid (AA). The effect of such factors as monomer concentration, dose, and average speed of the beam section of the accelerator conveyor was studied. The pristine and grafted samples of ion-track membranes were comprehensively studied by advanced physicochemical techniques. As a result of the studies, the optimal conditions for the radiation-induced grafting of PET ITMs with accelerated electrons were determined. A sufficiently high degree of grafting of AA while maintaining the mechanical strength of the polymer template were achieved for next conditions: the content of CuSO4 inhibitor is not more than 1%, the acrylic acid monomer concentration is not more than 10%, radiation dose in the range of 100–117 kGy.

Preparation of Cross-Linkable Waterborne Polyurethane-Acrylate Coating Films with Multifunctional Properties

Self-migration or unstable phase inversion occurs when the application conditions are varied, which limits the application of polyurethane-acrylate (PUA) composite films. In this paper, cross-linked polyurethane/poly(methyl methacrylate-co-borneol acrylate) shell microspheres were prepared by using the seeded emulsion polymerization method. The core-shell structure of these samples was identified by dynamic light scattering (DLS) and high-resolution transmission electron microscope (HR-TEM). Moreover, HR-TEM images indicated that the core-shell structure of the microsphere does not undergo complete phase inversion. In addition, with increasing content of borneol acrylate in the shell, the water resistance and antibacterial adhesion of films were improved. The X-ray photoelectron spectroscopy (XPS), Energy Dispersive Spectrometer (EDS), water contact angle (CA) measurements, antibacterial and anti-adhesion tests demonstrate that the C/N ratios of films from the inside to the upper surface had an obvious gradient in growth, indicating the shell component (polyborneol acrylate) was predominantly present at the surface of films after coalescence in cross-linked core-shell PUA. It was found that a suitable degree of cross-linking contributes to the segregation of the hydrophobic component (borneol groups) on the film surface. As a consequence, the excellent water resistance, cytocompatibility, and antibacterial properties endowed this series of polymer materials with promising application potential in the biomedical field.

Свойства сополимеров бутилакрилата с винилизо-бутиловым эфиром, полученных с использованием инициирующей системы триэтилборан – кислород компенсационным способом

The synthesis of copolymers of butyl acrylate with vinyl isobutyl ether was carried out by adding the active monomer to the excess of the comonomer when boiling in the presence of triethylborane. An organoelement co-initiator was isolated from a complex with hexamethylenediamine in a solution of vinyl butyl ether, with addition of methacrylic acid in an amount proportional to the amount of amine in moles, together with butyl acrylate. As a co-initiator of triethylborane, air oxygen was present in the reaction mixture at boiling of the vinyl butyl ether. The introduction of butyl acrylate was completed within 20 minutes. After that, the process was stopped (in the first series of samples), or else the reaction mixture was thermostated for another 40 minutes (in the second series of samples). At the end of polymerization, the liquid fraction was distilled off. The copolymer samples were isolated by removing the monomers under vacuum, and their conversion was evaluated gravimetrically by the dry residue. Molecular weight parameters for the samples were determined by gel permeation chromatography. The composition of the copolymers was determined by IR spectroscopy using a calibration graph based on the area of the characteristic peak. The obtained data suggest that during the copolymerization of butyl acrylate with vinyl isobutyl ether, a macromolecular chain is formed along two centers: oligomeric and low-molecular. The formation of an oligomer along with a low-molecular polymer, usually formed under such conditions at traditional radical initiation, is explained by the presence of boroxyl radicals in the reaction mixture, which are known in the oxidation of trialkylboranes. Due to the interaction of the latter with initiating R• or RO• radicals, which are also observed during the oxidation of trialkylboranes, or with oligomeric growing radicals, a growth center of the polymer chain is formed by the mechanism of reversible inhibition with a very low degree of polymerization. Continued thermostating of the reaction mixture after dosing butyl acrylate with methacrylic acid leads to a shift in the oligomeric mode in the direction of increasing the value of molecular weight; accordingly, M n increases and M w /M n decreases. This occurs because the copolymerization process continues in the absence of the initiator due to the reversible inhibition reaction. The time-dependent conversion rate is characterized by an abrupt decrease in the conversion rate by 40–60 %, which is also associated with the transition of the method of forming macromolecules with the predominantly high-speed bimolecular break to a process following the reversible inhibition mechanism according to the scheme, which runs at a much lower rate. The composition of the copolymers is characterized by a slightly higher equimolar content of acrylate, with a higher value of the relative activity of vinyl isobutyl ether, paired with butyl acrylate during copolymerization (r BA = 1.45 ± 0.07; r VBE ≈ 0; r BA = 5.2 ± 1.5; r ViBE ≈ 0).

In Situ Generation and Stabilization of Accessible Cu/Cu2 O Heterojunctions inside Organic Frameworks for Highly Efficient Catalysis.

Heterostructural metal/metal oxides are the very promising substituents of noble-metal catalysts; however, generation and further stabilization of accessible metal/metal oxide heterojunctions are very difficult. A strategy to encapsulate and stabilize Cu/Cu2 O nanojunctions in porous organic frameworks in situ is developed by tuning the acrylate contents in copper-based metal-organic frameworks (Cu-MOFs) and the pyrolytic conditions. The acrylate groups play important roles on improving the polymerization degree of organic frameworks and generating and stabilizing highly dispersed and accessible Cu/Cu2 O heteronanojunctions. As a result, pyrolysis of the MOF ZJU-199, consisting of three acrylates per ligand, generates abundant heterostructural Cu/Cu2 O discrete domains inside porous organic matrices at 350 °C, demonstrating excellent catalytic properties in liquid-phase hydrogenation of furfural into furfuryl alcohol, which are much superior to the non-noble metal-based catalysts.

In Situ Generation and Stabilization of Accessible Cu/Cu2O Heterojunctions inside Organic Frameworks for Highly Efficient Catalysis

AbstractHeterostructural metal/metal oxides are the very promising substituents of noble‐metal catalysts; however, generation and further stabilization of accessible metal/metal oxide heterojunctions are very difficult. A strategy to encapsulate and stabilize Cu/Cu2O nanojunctions in porous organic frameworks in situ is developed by tuning the acrylate contents in copper‐based metal–organic frameworks (Cu‐MOFs) and the pyrolytic conditions. The acrylate groups play important roles on improving the polymerization degree of organic frameworks and generating and stabilizing highly dispersed and accessible Cu/Cu2O heteronanojunctions. As a result, pyrolysis of the MOF ZJU‐199, consisting of three acrylates per ligand, generates abundant heterostructural Cu/Cu2O discrete domains inside porous organic matrices at 350 °C, demonstrating excellent catalytic properties in liquid‐phase hydrogenation of furfural into furfuryl alcohol, which are much superior to the non‐noble metal‐based catalysts.

Performance profiling of UV-grafted forward osmosis polyethersulfone membrane using multivariate classical scaling technique

In this work, Classical Scaling (CMDS) method was used to develop a set of membrane profile performance for various types of UV-grafted polyethersulfone (PES) membrane. Previously, there is no such profiling has been considered. The main motivation of the profiling is to determine what is the most preference impact factor which significantly influence the membrane strength during application. Initially, nine (9) different samples of modified PES membranes were prepared mainly by adopting numerous characterization parameters of acrylic acid monomer concentration and grafting time. Three (3) performance indicators namely water permeability (A), solute permeability (B) and structural parameter (S) were used as representing the foundation of membrane performance profile. In particular, the Euclidean and City-block scales were utilized to build up the multivariate profile based on two dimension configurations. The key finding suggests that the modified membranes were easily clustered based on its grafting mechanism. From the general observation on the compressed CMDS dimensional space, samples that fall above the x-axis in Euclidean scale configuration and those scattered samples in the City-block scale have relatively larger pores. Thus, the CMDS profiling tends to favor the pore size as the dominant impact factor in characterizing the membrane performance based on the three specified parameters that investigated.

Radiation-Chemical Synthesis of Crosslinked Films Based on N-Vinylcaprolactam Copolymers.

Water-soluble copolymers were obtained by graft copolymerization of N-vinylcaprolactam and 2-hydroxyethyl acrylate on polyvinyl alcohol. The chemical composition of the obtained graft copolymers was determined by IR spectroscopy. Cross-linked films were obtained by radiation treatment of water-soluble copolymers. To estimate the efficiency of the radiation crosslinking of films, the dependence of the yield of gel fraction on the absorbed dose was studied at different proportions of the initial components. It was established that the yield of the crosslinked fraction increases and the swelling capacity of polymer mesh decreases with increasing 2-hydroxyethyl acrylate content in graft copolymer and absorbed dose.

Evaluation of Isobornyl Acrylate Content in Medical Devices for Diabetes Treatment.

Background: Along with increased usage of continuous glucose monitors, flash glucose monitors, and patch pumps by patients with diabetes, the frequency of skin reactions has also increased. Skin irritation and itching can be annoying to users. However, more serious contact allergies to one or more components of the adhesives or plastic material of the housing of the devices can become lifelong. Redness and itchiness are so strong that patients can no longer use a particular system. In August 2017, a major culprit allergen, isobornyl acrylate (IBOA), was identified for these more serious reactions. Objectives: Our objective was to evaluate IBOA content in different medical products. Methods: The plastic material used for the housing of the Freestyle Libre (n = 3), Dexcom G6 (n = 3), and Enlite (n = 4) was analyzed for IBOA content by gas chromatography-mass spectrometry. Adhesives of the different systems were also analyzed. Results: IBOA was found in the housings of Freestyle Libre and Enlite sensor, but not in the Dexcom G6. Conclusions: Patients with an IBOA allergy should consider switching to a medical product without IBOA. Furthermore, removal of IBOA from devices that contact the skin is encouraged.

Relaxation behavior of random copolymers containing rigid fumarate and flexible acrylate segments by dynamic mechanical analysis

Due to the absence of a methylene spacer in the main chain, poly(substituted methylene)s with rigid structures possess some distinguished properties including a unique β-relaxation process. In this study, two series of random copolymers of diisopropyl fumarate (DiPF) with 1-adamantyl acrylate (AdA) and n-butyl acrylate (nBA) with various compositions were synthesized. The relaxation behavior of the copolymers was investigated using dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The α-relaxation temperature of the copolymers decreased as the acrylate content increased. Depending on the glass transition temperature (Tg) of the counterpart copolymers, that is, Tg = 156 °C for the homopolymer of AdA and Tg = –53 °C for the homopolymer of nBA, the β-relaxation temperature from the DiPF segments systematically shifted. While the β-relaxation temperature increased when copolymerized with AdA, the temperature decreased when copolymerized with nBA. Both copolymers maintained a high storage modulus of more than 10 MPa in the range between the α- and β-relaxation temperatures. The merging of the α and β processes at an intermediate composition was also observed. The random copolymerization of DiPF and acrylates enables us to fine tune the properties associated with the β-relaxation of DiPF segments. The relaxation behavior of random copolymers of diisopropyl fumarate (DiPF) with 1-adamantyl acrylate (AdA) and n-butyl acrylate with various compositions was investigated using dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The β relaxation temperature systematically shifted depending on the glass transition temperature of the counterpart copolymers, and the merging of the α and β processes at an intermediate composition was also observed. Thus, the random copolymerization of DiPF and acrylates enables us to fine tune the properties associated with the β relaxation of DiPF segments.

Synthesis and in situ functionalization of microfiltration membranes via high internal phase emulsion templating

AbstractThe continuous phase of high internal phase emulsions (HIPEs) can be polymerized to produce highly porous materials, known as polyHIPEs. The aim of this work was to synthesize polyHIPE microfiltration membranes having a hydrophobic bulk and a hydrophilic surface to enhance their performance. Therefore, in situ functionalization was performed through interfacial copolymerization of a hydrophobic monomer (butyl acrylate) in the continuous phase with a hydrophilic monomer (sodium acrylate) in the disperse phase. The functionalization of polyHIPEs was studied by using conductometric titration and Fourier transform IR spectroscopy. We show that the surface charge density of poly(butyl acrylate)‐based polyHIPEs can be controlled by varying the concentration of sodium acrylate in the disperse phase. PolyHIPE microfiltration membranes have higher intrinsic permeability (around 1.31 × 10−8 m2) in comparison to conventional microfiltration membranes. The interfacial copolymerization of sodium acrylate increases the permeability of microfiltration membranes. In addition, the rejection of polyHIPE microfiltration membranes was studied for the separation of microalgae. © 2019 Society of Chemical Industry

Synthesis and characterization of cross‐linked poly(sodium acrylate)/sodium silicate hydrogels

Transparent and intumescent polymer‐silicate hydrogels were synthesized by free‐radical polymerization, in the presence of the redox initiators system (potassium persulphate/sodium thiosulphate) and cross‐linking monomer (N,N′‐methylenebisacrylamide). Hydrogels obtained in such a manner were rheologically tested and it was found that the same sample with a different sodium acrylate concentration polymerized faster when its content was lower. The spectroscopic and thermal analysis proved that the polymer combines with sodium silicate by hydrogen bonds and during thermal degradation only small polymer fragments and water molecules were released. NMR studies have shown that the content of water glass causes shorter relaxation times. Conducted fire tests showed that glass panes systems filled with the tested hydrogels meet the relevant construction standards and what is their big advantage, a thin 1 mm layer of polymer‐silicate gel is sufficient for this purpose. We believe that these results will contribute to the development of intumescent hydrogels with enhanced fire‐retardant properties. POLYM. ENG. SCI., 59:1279–1287 2019. © 2019 Society of Plastics Engineers

Synthesis of special acrylic nanofibers as an appropriate precursor for conductive carbon nanofibers

Electrospinning technique is a significant approach used for producing special acrylic nanofibers (SANFs) through applying electrostatic field. SANFs were electrospun from polyacrylonitrile (PAN) copolymer solutions to be used as a precursor for carbon nanofibers (CNFs). The Box–Benkhen design (BBD) was used to elucidate the effects of the acrylic concentration (wt%), electrospinning voltage (kV), and spinning distance (cm) on the SANFs surface morphology and optimize these parameters. Based on BBD model the optimum SANFs diameter of 292 nm and 14.20% coefficient of variation, were collected at 9.3 wt% PAN concentration, 14 kV applied voltage, and 20 cm spinning distance. The optimized SANFs manufactured under BBD settings were specified by scanning electron microscope (SEM), mechanical tester, and differential scanning calorimeter (DSC). The optimized SANFs was stabilized in air and then carbonized in inert atmosphere at 800, 1000, and 1200 °C, respectively. The electrical conductivity of CNFs samples obtained from SANFs at 800 °C carbonization temperature is 2.31 × 10−2 S/cm, which is increased to 2.60 × 10+1 S/cm at 1200 °C. The results indicated that, the optimized SANFs possessed the most desired morphological properties, mechanical characteristics, and thermal stability; and thus they are appropriate for the development of high-performance CNFs.

Synthesis of fluorinated polyacrylate surfactant‐free core–shell latex by RAFT‐mediated polymerization‐induced self‐assembly: Effects of the concentration of hexafluorobutyl acrylate

AbstractA simple method for preparing fluorinated polyacrylate surfactant‐free latex was developed by RAFT‐mediated polymerization‐induced self‐assembly, in which the fluorinated polyacrylate copolymers formed a core–shell spherical morphology. The influence of the concentration of hexafluorobutyl acrylate on the properties of latex was systematically studied. The results showed that the average particle size increased, and the monomer conversion gradually increased with increasing the length of the second segment (PHFBA). And the monomer conversion progressively decreased, and average particle size gradually increased as the concentration of monomer (HFBA) increased from 2 wt% to 6 wt%. Furthermore, the thermal stability and the water contact angle of the film increased as the concentration of HFBA increased, and the water contact angle of film can be up to 127.3° when the concentration of HFBA was 6 wt%. XPS also showed that the fluorine‐containing groups well concentrated at the film–air interfaces during the annealing process.

Novel petroleum demulsifiers based on acrylic random copolymers

Although normally the copolymers used to remove water from crude oil have a block structure, two series of random acrylic copolymers were evaluated as petroleum demulsifiers. These acrylic copolymers, with two different butyl acrylate (BuA) and 2-ethylhexyl acrylate (2-EHA) contents, were synthesized by semi-continuous emulsion polymerization. Their weight-average molar mass () was varied by modifying the amount of chain transfer agent relative to the monomers from 0 to 8 wt%. FTIR and 13C-NMR spectroscopies confirmed that the conversion of the monomers was complete. The synthesized acrylic copolymers were subsequently evaluated as demulsifier agents in a Mexican heavy crude oil (10.24°API). Copolymers with 70 wt% butyl acrylate monomer and a weight-average molar mass above of 11 000 g mol−1 presented the greatest ability to remove emulsified water from the system. The demulsifying capability of the copolymer was evidenced to be strongly dependent on their molecular mass.HighlightsSynthesis of random acrylic copolymers (BuA-co-2-EHA) of different average molar mass ().Evaluation of random acrylic copolymers as demulsifiers of heavy crude oil.Weight-average molar mass () and monomer composition play an important role on the performance of random acrylic copolymers as demulsifiers.

Thermomechanical properties of PEGDA and its co-polymers

Abstract Current research activities focus on personalized, comfortable and safe products for systemic or local drug application in patients. Poly(ethylene glycol) diacrylate is in particular interest as a drug delivery material, as it shows appropriate biological properties such as hydrophilicity and low toxicity. Additionally, as an easily photopolymerizable compound it can be also utilized for the production of scaffolds with the use of different techniques such as stereolithography. Even though it is often used as a biomaterial or as a copolymer in many photopolymer systems for drug delivery, thermomechanical analysis and basic understanding are rare. Therefore, we investigated the tensile stress and the glass transition temperature of pure PEGDA and of its copolymers with 1,3-butanediol diacrylate or pentaerythritol triacrylate, as a function of the photoinitiator (PI) or acrylate concentration. Additionally, we demonstrated that the washing procedure decreases the tensile stress values. We showed, that by the means of composing PEGDA with these, it is possible to influence thermomechanical properties of the sample. Our outcomes have revealed, that there is no clear influence of the PI concentration on the thermomechanical properties. However there is an influence of the monomer concentration. Therefore, it should be possible to modify drug release profiles in future experiments.

Hot-melt pressure-sensitive adhesive for seamless bonding of nylon fabric Part II: Process parameter optimization for seamless bonding of nylon fabric

This study develops hot melt pressure sensitive adhesives (HMPSAs) for the seamless bonding of nylon fabric, using butyl acrylate as the main monomer material and mixing the functional monomer for polymerization. It is combined with 2-10phr diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide for the photoinitiator and ultraviolet irradiation is used to make a pre-polymer. The effects of butyl acrylate content, type of functional monomer, and 2-10phr diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide content on the molecular weight of acrylate pre-polymer are discussed, following the Taguchi method. The pre-polymer is then mixed with the reactive diluent glycidyl methacrylate blend and with 2-10phr diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, coated on a release film, irradiated by ultraviolet light, and cured into hot melt pressure sensitive adhesives. The adhesive properties of hot melt pressure sensitive adhesive bonding on nylon include the peel strength, the shear strength, adhesive warpage, adhesive color difference, and adhesive overflow, which are discussed following the Taguchi method and the elimination and choice translating reality method for multi-quality analysis. Hot melt pressure sensitive adhesives are implemented by optimization parameters for practical validation. The results show that the peel strength of hot melt pressure sensitive adhesives is 1.495 kg/cm, the shear strength of hot melt pressure sensitive adhesives is 14.326 kg/cm2, adhesive warpage is 0.93 mm, adhesive color difference is 1.66, and adhesive overflow is 0.97 mm. The performance of HMPSAs in this study is enhanced effective.

A cracked polymer templated Ag network for flexible transparent electrodes and heaters

In this work, an Ag metal network was fabricated on PET substrate using crackle lithography with acrylic based colloidal dispersion as sacrificial material. The effect of acrylic concentration on optical and electrical properties of Ag electrodes was investigated systematically. All of the Ag electrodes exhibited a high average transmittance of about 74.5%–79.9% in the visible range, and the minimum sheet resistance value reached 8.9 Ω/□. The Ag mesh also showed an excellent mechanical stability for both tensile strain and compressive strain. The fabricated Ag mesh transparent heater exhibited higher heating temperatures (∼95 °C) with lower input voltage (∼6 V), shorter response time (T < 40 s), and lower power consumption (126.9 °C cm2 W−1). Potential application of the Ag mesh based transparent heater in window defogging was also successfully demonstrated.