Plastic Coatings Research Articles

Major benzophenone concentrations and influence of food consumption among the general population in Korea, and the association with oxidative stress biomarker

Benzophenones (BPs) have been used as sunscreen agents and as ultraviolet stabilizers in plastic surface coatings for food packaging. However, few studies have been performed to examine the level of human exposure to BPs and the potential sources of such exposure. We evaluated the exposure levels to six major BPs (BP-1, BP-2, BP-3, BP-4, BP-8, and 4-hydroxybenzophenone (4-OH-BP)) among the adult population in two cities in Korea, and investigated the potential dietary sources of the BPs. Urinary levels of malondialdehyde (MDA) as an oxidative stress biomarker as well as their association with the levels of BPs were also analyzed. Among the six BPs analyzed, 4-OH-BP, BP-1, BP-3, and BP-4 were detected in 77%, 49%, 27%, and 21% of the population, respectively. BP concentrations were relatively higher in younger (people in their 20s and 30s) cosmetic users and leaner women. Even after the adjustment of age, body mass index, and cosmetic use, the consumption of frozen storage food, instant noodles, and instant coffee was significantly correlated with urinary BPs, and these associations were sex-dependent. No significant correlation was observed between the levels of BPs and levels of MDA. The results of the present study will be useful for developing plans of public health management of BPs.

Partial Obstruction of the Endotracheal Tube by the Plastic Coating Sheared from a Stylet.

A preterm with gestational age of 24 weeks was intubated at day of life 16. The intubation was done in a routine manner with the use of a stylet. It took a significant effort from the clinician to pull the stylet out after intubation. After intubation the respiratory status of the neonate deteriorated requiring significantly greater support. When ventilating and oxygenating the infant was getting progressively difficult, the decision was made to change the endotracheal tube (ETT). The cause for deterioration of respiratory status was then determined to be a sheared piece of plastic from the sheath of the stylet which was lodged in the lumen of the ETT. After removal of the plastic particle, the condition of the infant improved significantly.

Transparent nanocellulose-pigment composite films

Biodegradable coatings and films of cellulose nanofibers (CNFs) or a combination of CNFs and inorganic fillers, such as clay or calcium carbonate (CaCO3), can provide a replacement for non-biodegradable plastic coatings as barrier layers in packaging boards. In this work, transparent composite films were prepared from CNFs of Pinus radiata and Eucalyptus using different amounts of clay and CaCO3 as fillers. The impact of raw material (softwood vs. hardwood), TEMPO oxidation levels and filler type (clay vs. CaCO3) on film properties was studied. Pinus radiata CNF films had superior mechanical properties to Eucalyptus CNF films, but no significant differences were observed in the barrier and optical properties. Clay seemed to work better as filler compared to CaCO3, in terms of its impact on film properties. Composite films with CaCO3 as filler were highly brittle with inferior properties to clay-CNF films, and an uneven distribution and agglomeration of the CaCO3 mineral particles was evident in SEM images. Based on the results, clay as filler in CNF coatings is preferred for targeting packaging board applications. Rheological characterisation of the CNF suspensions revealed shear-thinning behaviour, with the CNF from Eucalyptus having higher viscosities and lower power-law indices when compared to the CNF from P. radiata.

UV-curable electromagnetic shielding composite films produced through waterborne polyurethane-acrylate bonded graphene oxide: preparation and effect of different diluents on the properties

AbstractUV-curable electromagnetic shielding composite films (UV-EMSF) were prepared with graphene oxide/polyurethane-acrylate (GO-PUA) oligomers, different diluents (styrene-butyl acrylate or tripropyleneglycol diacrylate-butyl acrylate or trimethylol propane triacrylate-butyl acrylate) and photoinitiator (2-hydroxy-2-methyl-1-phenyl-1-propanone). The chemical structures, morphology, crystallinity and thermal behavior of UV-EMSF were investigated by Fourier transform-infrared spectroscopy, scanning electron microscope, X-ray diffraction and thermogravimetric analysis. The stability, optical transparency and electrical conductivity of emulsions were measured. The effects of different diluents on the properties such as gel content, solvent resistance, hardness, tensile strength, contact angle and adhesion force were systemically studied. It was found that the emulsions had a good stability and the electrical conductivity of the emulsions indicated that the addition of GO had an effect on the electric conductivity. The prepared UV-EMSF composites with low-cost, low pollution and easy-to-prepare low resistivity have a great potential application in different areas such as electronic, electrical, communications, plastic coatings and wood finishes.

Effect of different photoinitiators on the properties of UV-cured electromagnetic shielding composites

Abstract A series of UV-cured electromagnetic shielding composites (UV-EMSC) containing different content of graphene oxide (GO) were prepared with oligomer, acrylate active diluents and different photoinitiators (Darocur 1173, Irgacure 184 or Irgacure 651). To fabricate conductive oligomer with low resistivity, polyurethane-acrylate (PUA) was used as the polymer matrix to help construct two-dimensional conductive networks consisting of GO. For forming conductive network structure, the surface functional groups (-OH, -COOH) of GO served as slightly conductive particles bonded with -NCO from the chain of polyurethane. The UV-EMSC exhibited a low resistivity of approximately 402 Ω·cm and an outstanding enhanced electrical conductivity of 249 mS/m at a GO content of 0.0200%. The effects of different photoinitiators on the properties of UV-cured films were investigated. The results indicate that the prepared UV-EMSC has great potential applications in different regions, such as in coatings of electronic, electrical, communications, plastic coatings and wood finishes.

Preparation and Properties of Graphene Oxide-Modified Waterborne Polyurethane-Acrylate Hybrids

A series of graphene oxide-modified waterborne polyurethane-acrylate (GEO/WPUA) hybrids were prepared and characterized by FT-IR, SEM, TEM and XRD. The result shows that graphene oxide in the hybrid has good dispersion. The mechanical property, thermal stability and water resistance of hybrids with different content of GEO were investigated. The results indicate that GEO/WPUA films have bigger tensile strength and hardness than pure WPUA. When the content of GEO is 0.015%, the hybrid has the best water resistance. The obtained GEO/WPUA hybrids have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Aspects of polymer surfaces wetting

Predicting quantitative characteristics of polymer surfaces wetting is one of the urgent tasks, which is to be solved at designing the systems of adhesives, coatings, printing materials, etc. The hydrophilic–lipophilic balance concept, which, however, allows only a qualitative effectiveness assessment of wetting agents is often used to solve this problem. The modified Owens–Wendt method, the theoretical basis of which allows to determine the relationship between the components of the surface tension of liquid and wetting efficiency of polymer surface with the known energy distribution is used in this paper. A practical approach, allowing to define the parameters of the surface tension of surfactants solutions, using the reference data on the components of the surface tension of liquids is proposed. It was shown that the method allows to achieve the high measurement accuracy of the specified solutions parameters and quantitatively predict the angles values of polymer surfaces wetting by liquid with the accuracy ± 4°. It was determined that solutions of anionic and nonionic surfactants are characterized by extremely low values of the polar component of the surface tension. At the same time, the values of solvent dispersion component increase at introducing these modifiers. The results are of practical importance, and can be used to develop wetting agents for the systems of polymeric adhesives, printing materials and coatings for plastics. Developing the obtained theoretical patterns will allow to take into account the influence of bi– and three–component solvent systems in the model that provides a quantitative description of such processes as dispersing highly–hydrophobic pigments and creating strong adhesion contacts in polymeric systems.

Preparation and properties of UV-curable waterborne graphene oxide/polyurethane-acrylate composites

In this work, the waterborne graphene oxide/polyurethane-acrylate (GO-WPUA) oligomer was prepared based on isophorone diisocyanate (IPDI), polyether polyol (NJ-220), graphene oxide (GO), dimethylol propionic acid (DMPA) and hydroxyethyl methylacrylate (HEMA). A series of the UV-curable waterborne graphene oxide/polyurethane-acrylate composites containing different content of GO were obtained with oligomer, monomers (BA and TPGDA) and photoinitiator Darocur 1173. The structure, viscosity, particle size and surface tension of emulsions were measured. Some mechanical performances, solvent resistance, the water absorption and thermal property of films were investigated. When the content of GO is 0·01%, the UV-curable film has the best mechanical property. The obtained composites have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Structural architecture and solubility of native and modified gliadin and glutenin proteins: non-crystalline molecular and atomic organization

Wheat gluten (WG) and its components, gliadin and glutenin proteins, form the largest polymers in nature, which complicates the structural architecture of these proteins. Wheat gluten, gliadin and glutenin proteins in unmodified form showed few secondary structural features. Structural modification of these proteins using heat, pressure and the chemical chaperone glycerol resulted in a shift to organized structure. In modified gliadin, nano-structural molecular arrangements in the form of hexagonal closed packed (HCP) assemblies with lattice parameter of (58 Å) were obvious together with development of intermolecular disulphide bonds. Modification of glutenin resulted in highly polymerized structure with proteins linked not only by disulphide bonds, but also with other covalent and irreversible bonds, as well as the highest proportion of β-sheets. From a combination of experimental evidence and protein algorithms, we have proposed tertiary structure models of unmodified and modified gliadin and glutenin proteins. An increased understanding of gliadin and glutenin proteins structure and behavior are of utmost importance to understand the applicability of these proteins for various applications including plastic materials, foams, adhesives, films and coatings.

Preparation, characterisation and properties of waterborne fluorinated polyurethane acrylate/SiO2 hybrid

Waterborne fluorinated polyurethan acrylate dispersion was prepared from the polyether polyol, isophorone diisocyanate, dimethylpropionic acid, hexafluorobutyl acrylate and trimethylolpropane triacrylate as monomers. Then, the prepolymer containing alkoxysilane Si(OR)3 was synthesised from dispersion and coupling agent methacryloxypropyl trimethoxy silane. The Si(OR)3 group was hydrolysed and reacted with different content tetraethoxysilane hydrolysis solutions in via hybridisation and gelatinous. A series of waterborne fluorinated polyurethane acrylate/SiO2 hybrids were prepared by sol–gel technique. The physical properties of dispersion such as storage stability, viscosity, particle size and surface tension were measured. The results indicated that all the prepared dispersions showed acceptable storage stability. The mechanical properties such as tensile strength, elongation at break and hardness and chemical resistance such as water absorption and acid resistance of the films were investigated. The hybrid materials were characterised using Fourier transform infrared, SEM and X-ray diffraction. The obtained hybrid materials have great potential application such as coatings, adhesion, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Harvesting light

Organic photovoltaics offer the tantalizing promise of low-cost plastic coatings that can be applied to building surfaces and roofing to generate electricity sustainably. Now, the demonstration that the addition of organic dyes can improve device performance by energy-transfer processes offers an exciting new opportunity.

Research Status of Plastic Vacuum Coating

Vacuum coating technology in the decoration, block, electromagnetic, sunlight, etc all have advantages, is widely used in various fields. Plastic vacuum coating technology can improve the surface quality of the plastics , It has the unique function of both plastics and metals. Introduced the plastic vacuum coating equipment, coating of paint and plastic vacuum coating in glass, foam, electromagnetic shielding and other aspects of the application of the latest research situation.

Preparation, Characterization, and Property Analysis of Environmentally Friendly Waterborne Polyurethane-Acrylate

Waterborne polyurethane (WPU) prepolymer was first prepared based on isophorone diisocyanate (IPDI), polyether polyol (NJ-210), dimethylol propionic acid (DMPA), and hydroxyethyl methyl acrylate (HEMA) via an in situ method. A series of waterborne polyurethane-acrylate (WPUA) dispersions were obtained with different proportions of acrylate (butyl acryolate and ethyl acrylate) and initiating agent by in situ dispersion technique. The structures and thermal properties of prepared WPU and WPUA were analyzed and characterized with FT-IR, UV-vis spectroscopy, and DSC. Performance of the emulsion and film was studied by means of apparent viscosity, particle size and polydispersity, surface tension, and mechanical properties. The results indicated that the particle sizes of the WPUA dispersions were larger than those of the pure WPU and the solvent resistance and mechanical properties of WPUA films were improved over those of the WPU film. The film had the greatest hardness and the least water absorption when the BA:EA mass ratio was 50:50. The obtained WPUAs have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings, and wood finishes.

Preparation, mechanical properties and surface morphologies of waterborne fluorinated polyurethane-acrylate

A series of waterborne fluorinated polyurethane-acrylate (WFPUA) materials were prepared from polyester polyol (NJ-330), isophorone diisocyanate (IPDI), dimethylol propionic acid (DMPA) and different content of hexafluorobutyl acrylate (FA). The chemical structure was characterized with FT-IR, 1H and 13C NMR; and the result confirmed that the FA monomer had been introduced into the chain of the WPUA polymer. The physical properties of WFPUA dispersions, mechanical properties and thermal properties of WFPUA films were measured. When the content of FA monomer was 3.0wt.%, the film exhibited the highest tensile strength, hardness and excellent chemical resistance. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used for characterization of cross and surface sections of the WFPUA films to verify the results. The obtained WFPUA materials have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Pulmonary Migration of a Fragment of Plastic Coating Sheared from a Stylet

BackgroundIn trauma patients, particularly with head immobilization, tracheal intubation without the use of a stylet may be impossible. ObjectivesTo report a very rare but potentially fatal complication that may happen in any Emergency Department: fracture of the plastic sheath of an intubation stylet, reported only twice before in the literature. Case ReportTwo large plastic fragments detached from a stylet while intubating a trauma patient. One piece was removed from the endotracheal tube a few hours later in the operating room. The second fragment migrated asymptomatically into the pulmonary airway. It was successfully retrieved from the right bronchus 24 h later. ConclusionThis potentially life-threatening event may go unnoticed after intubation if the endotracheal tube is not obstructed by the fragment. Gentle withdrawal of the stylet from the tube is essential to avoid stylet fracture. Careful examination of the stylet after intubation may suggest a stylet fracture.

Preparation and properties of waterborne poly(urethane acrylate)/silica dispersions and hybrid composites

The waterborne polyurethane acrylate (PUA) dispersion was prepared based on polyester polyol, isophorone diisocyanate, dimethylol propionic acid, butyl acrylate and trimethylolpropane triacrylate. Then, a series of PUA/SiO2 hybrid dispersions were prepared from PUA dispersion, coupling agent 3-glycidyloxypropyl trimethoxysilane and different content tetraethoxysilane hydrolysis solutions by the sol–gel process. The physical properties of PUA/SiO2 hybrid dispersions and the mechanical properties of PUA/SiO2 hybrid composites were measured. The PUA/SiO2 hybrids were characterised. The results showed that the nano-SiO2 particles of the hybrids had good dispersion and formed a good interfacial bonding layer on its surface. When the tetraethyl orthosilicate content was 0·5 wt-%, the hybrid film exhibited excellent comprehensive mechanical properties and water resistance. The tensile strength, hardness and water absorption of the film were 3·32 MPa, 90 and 6·7% respectively. The obtained PUA and hybrid composites have great potential application, such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Metallic and plastic dye solar cells

AbstractDye solar cells (DSCs) are quite a new technology in photovoltaics. The traditional DSCs are prepared on conductively coated glass substrates in high temperature using a batch process. Manufacturing the cells on low‐cost metal and plastic substrates would enable significant cost reductions as well as roll‐to‐roll mass production. There is a selection of metals and possible conducting coatings for plastics with varying electrical, optical, and chemical properties and price. The substrate has a dominant impact on the methods and materials that can be applied to make the cell and consequently on the resulting performance of the device. Furthermore, the substrates influence significantly the stability of the device. The main issue with plastics is their permeability whereas with metals, chemical stability in the electrolyte is themain concern. The leakage of electrolyte and the impact of water intake through the plastics can be affected by the material choices in particular with the electrolyte and dye composition. In the case of the metallic electrodes, the chemical stability can be improved by choosing a corrosion‐resistant metal, applying a blocking layer or changing to a less aggressive electrolyte. One major focus of the current research of the flexible DSCs is increasing the efficiency by improved low‐temperature preparation methods and materials especially for the photoelectrode. Another significant challenge is the development of noncorrosive electrolyte and dye combinations that work well even in the presence of significant amounts of water.This article is categorized under: Photovoltaics > Science and Materials Energy Research & Innovation > Science and Materials

Effect of heating on the performance of anticorrosive coatings

PurposeWhen coatings are applied to industrial equipment, they have to be able to stand the heat produced by solar energy and/or by different conditions on the process. Therefore, the purpose of this paper is to study the effect of temperature on the protective properties of coatings since this parameter degrades the polymer structure. In addition, the temperature effects on dry coating can also be specified.Design/methodology/approachIn order to know the behaviour of an organic coating at different temperatures, a drying aging cycle was performed by heating on substrate steel and free‐of‐substrate films during ten uninterrupted days at three and different temperatures: 65, 85 and 100°C. At the end of this period, the aged films were analyzed by means of electrochemical impedance spectroscopy (EIS) measurements, thermal analysis (DSC and TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electronic microscopy (SEM).FindingsThe most critical temperature for the aging was 85°C and “over‐cured” phenomenon were observed on the aged films which were reported by EIS, thermal and IR analyses.Practical ImplicationsThese aging conditions were tested on a very strong and rigid resin containing a barrier pigment. Thus, it can also be applied to other plastic coatings, such as vinyl or alkyd ones, by modifying the temperatures according to glass transition temperature (Tg), as well as the ageing time depending on the hardness and resistance of such coatings and, of course, the protective effect of the pigment. In addition, another aggressive electrolyte, such as synthetic sea water, chloride, sulphide media, as well as inhibitors or ecological pigments could be used in order to predict its behaviour in different corrosive media.Originality/valueThe value of this work is on the specific temperatures used for the aging method applied to a rigid resin which revealed the over‐cured phenomena and the behaviour of the pigment; so if it is applied to a more plastic and flexible coating, it may reveal other phenomena and promote other kind of degradation, maybe even more aggressive ones.

Waterborne Polyurethane-Acrylate Containing Different Polyether Polyols: Preparation and Properties

The waterborne polyurethane–acrylate (PUA) was prepared based on isophorone diisocyanate, polyether polyol, dimethylol propionic acid, hydroxyethyl methyl acrylate, butyl acrylate (BA) and styrene (St). Fourier transform infrared spectrometry (FT-IR), Ultraviolet-visible spectrophotometry (UV-Vis) and Differential scanning calorimetry (DSC) were employed to investigate the structures, optical transparency and thermal properties. Some physical properties of the aqueous dispersions such as viscosity, particle size and surface tension were measured. Some mechanical performances and solvent resistance of films were investigated. When the ratio of the BA/St was 30/70, the films had excellent water and alkali resistances. The obtained PUA composites have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.

Selective zinc ion detection by functionalised ZnO nanorods with ionophore

In this paper, highly dense and well aligned single-crystal zinc oxide nanorods were grown along the c-axis on a gold coated glass substrate using a low temperature aqueous chemical growth approach. The prepared ZnO nanorods were functionalized with plastic membrane coatings containing specific ionophore (12-crown-4) which is highly selective to zinc ions (Zn+2). The electrochemical response of the sensor was found to be linear over a relatively wide logarithmic concentration range from 1 μM to 100 mM. The proposed sensor showed a good linearity with a high sensitivity of ∼35 mV/decade for sensing Zn+2 ions. A fast response time of less than 5 s with a good selectivity, repeatability, reproducibility, and negligible response to common interferents ions such as calcium (Ca2+), magnesium (Mg2+), or potassium (K+), and iron (Fe+3) and copper (Cu+2) was also demonstrated. Moreover, the proposed sensor showed good stoichiometric results for potentiometric titration.