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Population exposure to endocrine disrupting chemical- bisphenols, which are used commonly in food containers and drinking water pipes in Europe, is above acceptable health and safety levels, according to updated research data. In order to evaluate the most abundant potential migrants in canned sweetened beverages marketed in Poland, we performed the HPLC-MS screening test of the migrants present in the can coating material. The analyzed samples represented the three top-ranked companies of the global soft drink market; it is reasonable to assume that the obtained data are of global validity. The tested can coatings and beverages contained bisphenols conjugates such as five butoxyethanol (BuOEtOH) adducts with bisphenol A diglycidyl ether (BADGE), one butoxyethanol adduct with bisphenol A monoglycidyl ether (BAMGE), and cyclo-di-BADGE. The performed HPLC-MS/MS analysis in the MRM mode enabled evaluation of the concentrations of the detected conjugates in canned beverages which were found to be very low, namely at the level of 1 µg/L. On the other hand, the high consumption of canned beverages may yield a risk associated with the presence of these compounds in the diet. The subsequent HPLC-QTOF-MS/MS experiments allowed, for the first time, a detailed determination of the fragmentation pathways of the detected migrants as well as detection of the isomers of the two migrants, namely BADGE + BuOEtOH and BADGE + BuOEtOH + HCl. [ABSTRACT FROM AUTHOR]

Epoxy coatings have common application as inner surface coating of food cans and have good mechanical properties, adhesion, flexibility and integrity and protect food cans against corrosion. These coatings contain bisphenol A diglycidyl ether (BADGE), also bisphenol A (BPA) units as residues, which are toxic and there is danger for migration of these derivatives into the Foodstuffs and poisoning them. In this research, titanium dioxide and silica nanoparticles were added into the formulation of epoxy can coating and its effects on migration of BPA and BADGE derivatives was investigated by using Inductively coupled plasma (ICP) and High-performance liquid chromatography (HPLC) test methods. Also, Physical and mechanical properties as well as coatings resultant safety were studied. Observations clarified that the coatings' hardness was increased by adding 0.5 wt % of SiO2 nanoparticles. Mechanical properties of coating had no noticeable changing by addition of TiO2 nanoparticles up to 0.75 wt %, but the gloss was decreased. The migration rates of TiO2 and SiO2 were negligible. The migration rate of BPA and BADGE derivatives were lower than acceptable limit mentioned in Commission Regulation (EU 10/2011), with Commission Regulation (EC) No 1895/2005, respectively. The lowest migration rate of the BADGE, beside its hydrated, also, hydrochloride derivatives (BADGEs), into acidic and alcoholic food simulants, was belong to the epoxy coating containing 0.5 and 0.15 wt % of TiO2 nanoparticles, respectively. Also, the lowest values of BADGEs migration, into the acidic and alcoholic food simulants, was belong to the coatings containing 0.15 and 0.3 wt % of SiO2, respectively. [ABSTRACT FROM AUTHOR]

Bisphenol A diglycidyl ether (BADGE) is widely present in the inner coating of metal food cans, from which it can migrate into food and generate harmful derivatives during storage, such as bisphenol A (2,3-dihydroxypropyl) glycidyl ether, bisphenol A (3-chloro-2-hydroxypropyl) glycidyl ether, and bisphenol A (3-chloro-2-hydroxypropyl) (2,3-dihydroxypropyl) glycidyl ether. Here, a gold-nanoparticle-based immunochromatographic strip assay based on a broad-spectrum polyclonal antibody was developed for the simultaneous detection of BADGE and its derivatives, which could be accomplished within 15 min. The quantitative analysis of the visualization results was performed using Adobe Photoshop CC 2021, and the detection limit, defined as the concentration causing 15% inhibition, was 0.97 ng/mL. The recoveries of BADGE and its derivatives at various spiking levels in canned food samples ranged from 79.86% to 93.81%. The detection results of the proposed immunochromatographic strip assay were validated via high-performance liquid chromatography, showing a good correlation coefficient (R2 = 0.9580). [ABSTRACT FROM AUTHOR]

Population exposure to endocrine disrupting chemical- bisphenols, which are used commonly in food containers and drinking water pipes in Europe, is above acceptable health and safety levels, according to updated research data. In order to evaluate the most abundant potential migrants in canned sweetened beverages marketed in Poland, we performed the HPLC-MS screening test of the migrants present in the can coating material. The analyzed samples represented the three top-ranked companies of the global soft drink market; it is reasonable to assume that the obtained data are of global validity. The tested can coatings and beverages contained bisphenols conjugates such as five butoxyethanol (BuOEtOH) adducts with bisphenol A diglycidyl ether (BADGE), one butoxyethanol adduct with bisphenol A monoglycidyl ether (BAMGE), and cyclo-di-BADGE. The performed HPLC-MS/MS analysis in the MRM mode enabled evaluation of the concentrations of the detected conjugates in canned beverages which were found to be very low, namely at the level of 1 µg/L. On the other hand, the high consumption of canned beverages may yield a risk associated with the presence of these compounds in the diet. The subsequent HPLC-QTOF-MS/MS experiments allowed, for the first time, a detailed determination of the fragmentation pathways of the detected migrants as well as detection of the isomers of the two migrants, namely BADGE + BuOEtOH and BADGE + BuOEtOH + HCl.

BACKGROUND: Recent studies have reported that endocrine-disrupting compound (EDC) exposure is related to food sensitization. Bisphenol A diglycidyl ether (BADGE) is one of the most widespread EDCs and its biological effects are considered to be greater on children than on adults. This study investigated the relationship between serum BADGE-specific immunoglobulin G (IgG) concentrations and food sensitization in young children by measuring food-specific IgE levels. METHODS: In total, 98 young children (59 boys and 39 girls; median age: 7 months; 25th and 75th percentile ages: 6 and 8 months, respectively) were enrolled. Blood samples were collected twice from all children (median sampling interval: 6 months; 25th and 75th percentile: 5 and 7 months). Food sensitization was evaluated based on food-specific IgE titers (egg white, milk, and wheat), which were determined using the capsulated hydrophilic carrier polymer-radioallergosorbent test. Furthermore, a dot-blotting assay for BADGE-specific IgG and quantitative reverse-transcriptase PCR for IL-6, IL-8, IL-10, and COX-2 mRNA expression were conducted. RESULTS: BADGE-specific IgG was detected in 20% of study subjects. A significant association was observed between the presence of BADGE-specific IgG and elevated wheat-specific IgE levels (OR = 3.56; 95% CI 1.13-11.2; P = 0.031). This relationship was particularly strong in girls (OR = 9.46; 95% CI 1.01-89.0; P = 0.049). A slight but non-significant association was noted between the presence of BADGE-specific IgG and elevated milk-specific IgE levels (OR = 2.77; 95% CI 0.93-8.22; P = 0.067). The expression of IL-6 mRNA among children with BADGE-specific IgG tended to increase, along with wheat-specific IgE levels. CONCLUSION: BADGE exposure might enhance food sensitization in early childhood. Therefore, this should be strictly regulated, especially in younger children.

Bisphenol A diglycidyl ether (BADGE)-based epoxy resin is one of the most widely used epoxy resins with an annual production amount of several million tons. Compared with all other legacy or emerging organic compounds, BADGE is special due to its toxicity and high reactivity in the environment. More and more studies are available on its analytical methods, occurrence, transformation and toxicity. Here, we provided a comprehensive review of the current BADGE-related studies, with focus on its production, application, available analytical methods, occurrences in the environment and human specimen, abiotic and biotic transformation, as well as the in vitro and in vivo toxicities. The available data show that BADGE and its derivatives are ubiquitous environmental chemicals and often well detected in human specimens. For their analysis, a water-free sample pretreatment should be considered to avoid hydrolysis. Additionally, their complex reactions with endogenous metabolites are areas of great interest. To date, the monitoring and further understanding of their transport and fate in the environment are still quite lacking, comparing with its analogues bisphenol A (BPA) and bisphenol S (BPS). In terms of toxicity, the summary of its current studies and Environmental Protection Agency (EPA) ToxCast toxicity database suggests BADGE might be an endocrine disruptor, though more detailed evidence is still needed to confirm this hypothesis in in vivo animal models. Future study of BADGE should focus on its metabolic transformation, reaction with protein and validation of its role as an endocrine disruptor. We believe that the elucidation of BADGEs can greatly enhance our understandings of those reactive compounds in the environment and human.

Aim: The aim of this study was to investigate the involvement of peroxisome proliferator-activated receptor gamma (PPAR-γ) in renal protection offered by sinapic acid in cisplatin-induced nephrotoxicity in male rats. Materials and Methods: Nephrotoxicity was induced by single dose of cisplatin (5 mg/kg, intraperitoneal [i.p.]) in rats. Cisplatin-induced nephrotoxicity was assessed by measuring serum creatinine, creatinine clearance, urea, uric acid, potassium, magnesium levels, fractional excretion of sodium, and microproteinuria in rats. Superoxide anion generation, thiobarbituric acid reactive substances, myeloperoxidase activity, and reduced glutathione levels were measured to assess oxidative stress in renal tissues. Hematoxylin and eosin stain showed renal histological changes. Results: The significant changes in serum and urinary parameters, elevated oxidative stress, and renal histological changes established the induction of nephrotoxicity. Sinapic acid treatment (20 and 40 mg/kg, orally [p.o.]) provides dose-dependent and significant (P < 0.05) nephroprotection against cisplatin-mediated nephrotoxicity in rats. Nephroprotective effect of sinapic acid was abolished by PPAR-γ inhibitor, bisphenol A diglycidyl ether (30 mg/kg, i.p.) in rats. Conclusion: It is concluded that PPAR-γ agonism serves as one of the mechanisms in sinapic acid-mediated renoprotection.

Abstract Background Recent studies have reported that endocrine-disrupting compound (EDC) exposure is related to food sensitization. Bisphenol A diglycidyl ether (BADGE) is one of the most widespread EDCs and its biological effects are considered to be greater on children than on adults. This study investigated the relationship between serum BADGE-specific immunoglobulin G (IgG) concentrations and food sensitization in young children by measuring food-specific IgE levels. Methods In total, 98 young children (59 boys and 39 girls; median age: 7 months; 25th and 75th percentile ages: 6 and 8 months, respectively) were enrolled. Blood samples were collected twice from all children (median sampling interval: 6 months; 25th and 75th percentile: 5 and 7 months). Food sensitization was evaluated based on food-specific IgE titers (egg white, milk, and wheat), which were determined using the capsulated hydrophilic carrier polymer-radioallergosorbent test. Furthermore, a dot-blotting assay for BADGE-specific IgG and quantitative reverse-transcriptase PCR for IL-6, IL-8, IL-10, and COX-2 mRNA expression were conducted. Results BADGE-specific IgG was detected in 20% of study subjects. A significant association was observed between the presence of BADGE-specific IgG and elevated wheat-specific IgE levels (OR = 3.56; 95% CI 1.13–11.2; P = 0.031). This relationship was particularly strong in girls (OR = 9.46; 95% CI 1.01–89.0; P = 0.049). A slight but non-significant association was noted between the presence of BADGE-specific IgG and elevated milk-specific IgE levels (OR = 2.77; 95% CI 0.93–8.22; P = 0.067). The expression of IL-6 mRNA among children with BADGE-specific IgG tended to increase, along with wheat-specific IgE levels. Conclusion BADGE exposure might enhance food sensitization in early childhood. Therefore, this should be strictly regulated, especially in younger children.

The increase of fertility performance in sows is one of the biggest achievements in pig production over the last 30 years. Nevertheless, pig farms using artificial insemination (AI) repeatedly experienced in recent year's fertility problems with dramatic consequences due to toxic compounds from plastic semen bags. In particular, bisphenol A diglycidyl-ether (BADGE) present in multilayer plastic bags can leach into the semen and could affect the functionality of the spermatozoa. Former studies could not find any alterations in spermatozoa based on the exposure to BADGE. The aim of the study was to evaluate effects of BADGE on boar spermatozoa using an extended panel of spermatological methods. In spring 2019, a large drop in farrowing rates from 92.6 ± 2.3% to 63.7 ± 11.1% in four sow farms in Croatia was detected. In migration studies, BADGE could be identified as a causal toxic compound and leached into the extended semen in concentration of 0.37 ± 0.05 mg/L. Detailed spermatological studies showed that significant predictors for effects on spermatozoa were different levels of motility and kinematic data after a prolonged storage time, thermo-resistance test (prolonged incubation time), mitochondrial activity, membrane integrity and fluidity. No serious effects were observed for sperm morphology and DNA fragmentation. These results provide new insights into the development of a new quality assurance concept for a detailed spermatological examination during testing of plastic materials for boar semen preservation. It could be shown that boar spermatozoa are an excellent biosensor to detect potential toxicity and fertility-relevant compounds. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate the involvement of peroxisome proliferator-activated receptor gamma (PPAR-γ) in renal protection offered by sinapic acid in cisplatin-induced nephrotoxicity in male rats. Materials and Methods: Nephrotoxicity was induced by single dose of cisplatin (5 mg/kg, intraperitoneal [i.p.]) in rats. Cisplatin-induced nephrotoxicity was assessed by measuring serum creatinine, creatinine clearance, urea, uric acid, potassium, magnesium levels, fractional excretion of sodium, and microproteinuria in rats. Superoxide anion generation, thiobarbituric acid reactive substances, myeloperoxidase activity, and reduced glutathione levels were measured to assess oxidative stress in renal tissues. Hematoxylin and eosin stain showed renal histological changes. Results: The significant changes in serum and urinary parameters, elevated oxidative stress, and renal histological changes established the induction of nephrotoxicity. Sinapic acid treatment (20 and 40 mg/kg, orally [p.o.]) provides dose-dependent and significant (P < 0.05) nephroprotection against cisplatin-mediated nephrotoxicity in rats. Nephroprotective effect of sinapic acid was abolished by PPAR-γ inhibitor, bisphenol A diglycidyl ether (30 mg/kg, i.p.) in rats. Conclusion: It is concluded that PPAR-γ agonism serves as one of the mechanisms in sinapic acid-mediated renoprotection. [ABSTRACT FROM AUTHOR]

In this manuscript, a sensitive and selective molecular imprinted electrochemical sensor for the detection of bisphenol A diglycidyl ether (BADGE) in canned oil was developed. Using BADGE as template, pyrrole as functional monomer, after electropolymerization and elution processes, the molecular imprinted film for the special recognition of BADGE was prepared on the surface of platinum disk electrode. Every step in the experiment was verified by field emission scanning electron microscope (SEM), microscopic fourier transform infrared spectroscopy (Micro‐FTIR), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The experimental parameters in the assay were optimized, and the linear range of the MIP sensor was 0.05 μmol dm−3 to 10 μmol dm−3 with the detection limit of 0.04 μmol dm−3 based on S/N=3. The sensor was applied to edible oil samples for detection with a good accuracy, which could be used as a new strategy for sensitive, rapid, simple and cost‐effective screening of BADGE. [ABSTRACT FROM AUTHOR]

To investigate how non-exponential response could vary under different conditions, we studied the effects of adding 2 nm size polyhedral oligomeric silsesquioxane (POSS) to diglycidyl ether of bisphenol-A, whose molecules have the same terminal (epoxide) dipoles as the tentacle-like side chains attached to the silsesquioxane core of the POSS molecule. Dielectric relaxation spectra show that, on initial addition, the POSS nano-heterogeneity decreases the non-exponential response parameter β, which is consistent with the dynamic heterogeneity view, but it also decreases the relaxation time τm, which is inconsistent with that view. The variations in β and τm with the composition have a thermal equivalence. Despite the lack of translational diffusion required for dynamic heterogeneity, plastic crystals show non-exponential response and non-Arrhenius dynamics. Measurements of β and τm seem more appropriate than using probe molecules or modeling nonlinear response data as a sum of linear responses for testing the dynamic heterogeneity view. Data on molecular liquid mixtures is not generally consistent with this view, and adding a solute does not always decrease β. Studies of mixtures of different size rigid molecules with identical dipolar groups, including polymers, may be useful for comparing the relative effects of temperature and molecular size on β and τm. [ABSTRACT FROM AUTHOR]

Abstract Epoxy resin systems based on Diglycidyl ethers bisphenol A (DGEBA) and methyl tetrahydrophthalic anhydride (MTHPA) often experience problems related to brittleness, large internal stress, undesirable shock resistance, low fatigue durability and heat resistance. It is thus of vital importance to improve the thermal and mechanical properties of the DGEBA/MTHPA epoxy resins. In this study, the effects of the addition of carbon nanobud (CNB) to the mechanical properties and thermal conductivities of cross-linked epoxy resins based on the DGEBA and MTHPA are investigated using molecular dynamics (MD) simulations. Different molecular models are constructed, and comparisons are made for the pure DGEBA/MTHPA and their nanocomposites containing carbon nanotube (CNT), single CNB, functionalized nanobuds with one and four fullerenes attached to the CNT, respectively. It has been shown that all these reinforced epoxy systems have an increased glass transition temperature (Tg), Young's modulus and shear modulus, whereas the DGEBA/MTHPA/FCNBs performs the best. Compared with pure DGEBA/MTHPA, the Tg value of the DGEBA/MTHPA/FCNBs increases by 34.3% (140 K). The improvement of the Young's modulus and shear modulus is also significant, with an increase of 44.5% and 51.8%, respectively. The enhancement in the thermal conductivity, however, is limited due to the small length of SWCNTs/CNBs introduced. [ABSTRACT FROM AUTHOR]

Abstract Bisphenol A diglycidy ether (BADGE) and its derivatives are epoxy resins and widely used as emerging plasticizers in food packages and material coating. Though known as endocrine disruptors, little information is available on their occurrence, exposure routes and toxicity. Besides, the analysis of BADGE and its derivatives has always been a challenge due to their reactive chemical properties and the background contamination. Therefore, we firstly developed a novel water-free method to analyze BADGE and its derivatives in dust samples together with other two typical plasticizers bisphenol A (BPA) and bisphenol S (BPS). In order to investigate the levels in paired dust and urine samples, 33 paired samples were collected from Singapore. In both dust and urine samples, the predominant compounds were BPA, BADGE-2H 2 O and BPS. A significantly positive correlation of BPA levels in paired dust and urine samples was observed in this small-scale study. To tentatively explore the human health effect from exposure to these bisphenol plasticizers, we assessed the correlation between the urinary concentrations of these compounds and oxo-2'-deoxyguanosine (8-OHdG), an oxidative stress biomarker. The result showed that 8-OHdG levels in urine samples was positively correlated with urinary BPA level and body mass index (BMI), suggesting that elevated oxidative stress might be associated with BPA exposure and obesity. In the future, a larger scale study is warranted due to the limited sample size in this study. Graphical abstract Image 1 Highlights • Development of a novel water-free method to analyse BADGE in the dust. • BADGE and its derivatives were widely detected in the dust and urine samples. • BPA in the urine was significantly correlated with BPA in the dust. • BPA in the urine was significantly correlated with oxidative stress biomarker. [ABSTRACT FROM AUTHOR]

Abstract BADGE (bisphenol A diglycidyl ether) is a synthesis product of bisphenol A (BPA), which, like other plasticizers, can cross the human placenta and reach the foetus. However, compared to BPA, there is almost no toxicological information. This work investigates the toxicity, endocrine and lipid disruption potential of BADGE and its hydrolysed and chlorinated derivatives (BADGE·H 2 O and BADGE·2HCl) in human placental JEG-3 cells. The analysis of culture medium by HPLC-ESI(+)-QqQ evidenced a good bioavailability of BADGE·2HCl and BADGE·H 2 O, but low stability of BADGE. Regardless, BADGE·2HCl and BADGE showed higher cytotoxicity than BADGE·H 2 O, which was the only compound that significantly inhibited CYP19 activity (IC 50 49 ± 5 μM). JEG-3 cells lipidome analyzed by FIA-ESI(+/−)-Orbitrap was significantly altered by exposure to BADGE·2HCl and BADGE at concentrations at the low μM range. BADGE·2HCl lead to a strong decrease of diacyl- and triacyl-glycerides (DGs,TGs) together with some membrane lipids, while BADGE lead to an accumulation of TGs. The results evidence the ability of BADGE and derivatives to affect placental lipid handling and to modulate placental CYP19 activity (BADGE·H 2 O) and highlights the need to monitor human exposure to these compounds, at least as intensely as BPA is monitored. Graphical abstract Image 1 Highlights • BADGE and derivatives show higher cytotoxicity than bisphenol A in JEG-3 cells. • BADGE·H 2 O inhibits aromatase activity in JEG-3 cells, acting as endocrine disrupter. • BADGE and BADGE·H 2 O are rapidly hydrolysed in culture medium. • BADGE·2HCl alters the cell lipidome by decreasing the amount of neutral lipids. • Exposure to BADGE increases intracellular concentration of triacylglycerides. Bisphenol A diglycidyl ether and derivatives disrupt placenta cell lipidome and show comparatively higher toxicity than bisphenol A. [ABSTRACT FROM AUTHOR]

Gradient reversed-phase high-performance liquid chromatography with photodiode array detection was used for separation, detection and quantification of bisphenol-A-diglycidyl ether (BADGE) and some of its reaction products, namely, BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl in pure form and in canned foods, where canned beans and tuna were used as representatives of aqueous and oil-in-water food matrices, respectively. The proposed method had a linear range of 0.01–0.5 μg g−1for BADGE·HCl·H2O, BADGE·H2O, BADGE·2HCl and 0.02–0.7 μg g−1for BADGE in aqueous food matrices. In oil-in-water matrices, the method was proven to be sensitive over a linear range of 0.01–0.5 μg g−1for BADGE·HCl·H2O, BADGE·H2O and 0.02–0.7 μg g−1for BADGE·2HCl and BADGE. The limits of detection and quantification ranged from 0.24 to 1.22 ng g−1and 0.73 to 14.07 ng g−1, respectively. Excellent intraday and interday precision (n = 9) were obtained with RSD% of 0.84–2.19% and 1.88–2.52%, respectively. Accuracy was measured at five concentration levels and the recoveries ranged from 96.31% to 98.76% with an acceptable variation of ±0.9–2.87. Results suggest that the proposed method could be applied for the routine analysis of the studied compounds in their laboratory-prepared mixtures and in various types of canned foods following the limits and regulations of the European Union. [ABSTRACT FROM AUTHOR]

Epoxy‐ended hyperbranched polymers (EHBP) has become a class of additives for diglycidyl ether of bisphenol‐A (DGEBA), but it is tedious processes retards wide application. Here, we prepared EHBP by a thiol‐ene click reaction between thiol‐terminated hyperbranched polyesters and allyl glycidyl ether and modified DGEBA. The incorporation of EHBP significantly enhanced the toughness and strength of DGEBA. The mechanical properties of EHBP/DGEBA composite increased remarkably with the increasing EHBP molecular weight initially, and then decreased with further increase of EHBP molecular weight. The maximum increase of mechanical properties was observed in EHBP‐12/DGEBA composites. With increasing EHBPE‐12 content, the mechanical performance of the EHBP‐12/DGEBA composites increased firstly and plateaued at 9 wt% EHBP‐2. At 9 wt% EHBP‐12 content, the tensile strength, flexural strength and impact strength increased to 74.46 MPa, 143.58 MPa, and 39.09 kJ m−2, respectively. When loading was increased from 12 to 15 wt%, the mechanical performance started to decrease. The use of EHBP slightly decreased the thermal stability and the glass transition temperature. Protonema observed in the fracture surface can be used to explain the significant improvement in mechanical properties. POLYM. ENG. SCI., 58:1703–1709, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A commercial diglycidyl ether of bisphenol A monomer (Baxxores™ ER 2200, eew 182 g/mole, DGEBA) is thermally polymerized in the presence of an ionic liquid, 1-ethyl-3-methylimidazolium acetate at a variety of loadings (5–45 wt %). The loss modulus data for cured samples, containing 5 wt % initiator, display at least two thermal transitions and the highest storage modulus occurs in the sample that has been cured for the shortest time at the lowest temperature. Samples that are exposed to higher temperatures (140, 150 °C) yield more heterogenous networks, whereas following exposure to a much shorter/lower temperature cure schedule (80 °C) exhibits a considerably higher damping ability than the other samples, coupled with a lower glass transition temperature. Differential scanning calorimetry reveals that the latter sample achieves a conversion of 95%, while crosslink densities for the DGEBA samples containing 5 wt % and 15 wt % are respectively 9.5 × 10 −3  mol. dm −3 and 1.2 × 10 −3  mol. dm −3 (when cured to 80 °C) and 2.0 × 10 −2  mol. dm −3 and 2.4 × 10 −3  mol. dm −3 (when cured to 140 °C). [ABSTRACT FROM AUTHOR]

Abstract: An evolving understanding of elastomeric polymer nanocomposites continues to expand commercial, defense, and industrial products and applications. This work explores the thermomechanical properties of elastomeric nanocomposites prepared from bisphenol A diglycidyl ether and three amine‐terminated poly(propylene oxides) (Jeffamines). The Jeffamines investigated include difunctional crosslinkers with molecular weights of 2000 and 4000 g mol−1 and a trifunctional crosslinker with a molecular weight of 3000 g mol−1. Additionally, carbon nanotubes (CNTs) are added, up to 1.25 wt%, to each thermoset. The findings indicate that the T g and storage modulus of the polymer nanocomposites can be controlled independently within narrow concentration windows, and that effects observed following CNT incorporation are dependent on the crosslinker molecular weight. Finally, the impact of crosslinker length and architecture as well as CNT addition on the molecular weight between crosslink points in the glassy and rubbery states are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT: In some applications, homopolymerized epoxies, which offer better biocompatibility and lower water absorption than amine‐ and anhydride‐cured epoxy, are more preferable; however, using homopolymerized epoxy as matrix in composites still remains a challenge. Herein, homopolymerized bisphenol A diglycidyl ether curing systems with simultaneously improved tensile strength, impact strength, and glass transition temperature (Tg) were achieved by addition of small amounts of tetra‐functional epoxies (TFTEs) with different spacer lengths. Effects of spacer length in TFTE on thermal and mechanical properties were investigated. Results indicated that TFTE with the longest spacer length shows the best mechanical performance. In addition, effects of TFTE loading on thermal and mechanical properties were discussed. Compared with neat bisphenol A diglycidyl ether, addition of 5% tetraglycidyl‐1,10‐bis(triphenylmethane) decane leads to simultaneous improvements in tensile strength, impact strength, and Tg. Effects of thermal cycling on the mechanical properties were also reported. Results suggest that the modified homopolymerized epoxy shows good performances and could be used as matrix materials and possibly in some dental applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46431. [ABSTRACT FROM AUTHOR]

ABSTRACT: Heat and ultraviolet (UV)‐induced bonding and debonding (BDB) adhesives were designed and prepared through blending an epoxy resin, diglycidyl ether of bisphenol A (DGEBA) with an epoxy acrylate resin, bisphenol‐A epoxy acrylate resin (BEA). The variation of the chemical structure of DGEBA and BEA in the sequential heat‐ and UV‐curing processes was characterized by Fourier transform infrared spectroscopy (FTIR). The FTIR results indicate that DGEBA and BEA successfully took part in both the heat‐curing and UV‐curing processes. The effects of the mass ratio of BEA to DGEBA, amount of heat‐curing agent, type of diluents, and UV irradiation time on the BDB properties of BDB adhesive were systematically investigated. The results show that the bonding strength increases with the decrease of the mass ratio of BEA to DGEBA and with the increase of the amount of heat‐curing agent in a certain range. The debonding strength decreases with the increase of the mass ratio of BEA to DGEBA. The mass ratio of BEA to DGEBA was set at 10 to ensure the ratio of the bonding strength to debonding strength greater than 10 times. The debonding strength of BDB adhesives also depends on the UV irradiation time, decreasing with the increase of UV irradiation time in a certain range. Based on the FTIR results and the dependence of the bonding and deboning strengths on the reaction conditions, a possible BDB mechanism of BDB adhesive was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46435. [ABSTRACT FROM AUTHOR]

Epoxy-ended hyperbranched polymers (EHPs), as important type of functional thermosetting hyperbranched polymers, have attracted broad and continuing interest from both academic and industrial researchers. Benefiting from their high-crosslinking ability, void-containing topological structure and very low viscosity, EHPs have been widely applied in reinforcing and toughening diglycidyl ether of bisphenol-A (DGEBA) and in solvent-free or environmentally-friendly coatings. Therefore, the design and synthesis of EHPs provide a robust tool for controlling the interfacial interaction between EHPs and DGEBA to finally gain excellent comprehensive performance. In this review, the perspectives and recent advances of preparation methods, performance control and promising applications of various EHPs have been comprehensively summarized. In addition, a single toughening function, a simultaneously reinforcing and toughening function and the mechanism of DGEBA by EHPs are also discussed and investigated by integrating molecular simulations, dynamic mechanical analysis (DMA) and scanning electron microscope (SEM) technologies. EHPs with high contents of epoxy group show simultaneous reinforcing and toughening in DGEBA, regardless of their aliphatic and aromatic structures, and whether there is phase-separation or homogenous structure associated with the fractured surface. The simultaneous reinforcing and toughening mechanism changes the conventional conception of inter-contradiction between the toughening and reinforcing function. It was also found that EHPs with different synthetic strategies and diverse performance have allowed an increasing number of versatile industrial applications. [ABSTRACT FROM AUTHOR]

Multivariate curve resolution (MCR) was applied to a hetero-spectrally combined dataset consisting of mid-infrared (MIR) and near-infrared (NIR) spectra collected during the isothermal curing reaction of an epoxy resin. An epoxy monomer, bisphenol A diglycidyl ether (BADGE), and a hardening agent, 4,4′-diaminodiphenyl methane (DDM), were used for the reaction. The fundamental modes of the N H and O H stretches were highly overlapped in the MIR region, while their first overtones could be independently identified in the NIR region. The concentration profiles obtained by MCR using the hetero-spectral combination showed good agreement with the results of calculations based on the Beer-Lambert law and the mass balance. The band assignments and absorption sites estimated by the analysis also showed good agreement with the results using two-dimensional (2D) hetero-correlation spectroscopy. [ABSTRACT FROM AUTHOR]

Although studies have examined leaching of bisphenol A (BPA) from dental sealants into saliva, occurrence of BPA, bisphenol A diglycidyl ether (BADGE), and their derivatives in dental sealants themselves has not been investigated. In this study, concentrations of eight bisphenol analogues (BPs), BADGE and its derivatives (BADGEs), including BADGE‧H 2 O, BADGE‧HCl, BADGE‧2H 2 O, BADGE‧2HCl, and BADGE‧H 2 O‧HCl, were determined in 70 dental sealants collected from the U.S. market. Of the 70 dental sealants analyzed, 65 contained at least one of the target chemicals measured. BADGE‧2H 2 O was the most abundant compound, found at concentrations of up to 1780 µg/g. The geometric mean (GM) concentration of total BADGEs was 47.8 µg/g, which was two to three orders of magnitude higher than that of total BPs (GM: 539 ng/g). BPA was found in 46% of the sealants and BADGEs was found in 87% of the sealants analyzed. Majority of the dental sealants analyzed in this study were manufactured in the United States and Korea; no significant differences were observed in the concentrations of BPs and BADGEs between the two countries. An exposure assessment was made based on the concentrations of BPs and BADGEs measured in sealants and their application rates in dentistry. The worst-case exposure scenario with the highest measured concentration of total BPs and BADGEs and application on 8 teeth at 8 mg each yielded an estimated daily intake (EDI) of 1670 and 5850 ng/kg·bw/day for adults and children, respectively. Although the EDI is below the specific migration limit set by the European Food Safety Authority, dental sealants are a source of exposure to BPs and BADGEs, especially in children. [ABSTRACT FROM AUTHOR]

This study investigated how the properties of a polymeric can coating film, such as thickness and crosslink density as well as the type of migrant, influence the migration kinetics of model migrants in an attempt to better understand, model and control the migration process. Four model migrants were used BADGE (bisphenol A diglycidyl ether), BADGE·H 2 O, cyclo-diBADGE and Uvitex OB, that differ in size and polarity. Fatty and aqueous food simulants were used at high temperatures (70–130 °C). The apparent diffusion coefficients were found to decrease with increasing crosslink density, while they increased with increasing film thickness. The apparent activation energy of BADGE and BADGE-related compounds was calculated from the diffusion data and were high, in the range of 250–264 kJ mol − 1 . The polarity of the simulant and the polarity of the migrant were found to influence migration. The results can be used to improve existing migration models, and thereby help to reduce migration from packaging into food by using safety-by-design approaches in new product development. [ABSTRACT FROM AUTHOR]

This study evaluated the migration of bisphenol A diglycidyl ether (BADGE) and its chlorinated and hydrolyzed derivatives and bisphenol F diglycidyl ether (BFDGE) from the inner surface coatings of food containers into three food simulants including 3% (w/v) aqueous acetic acid, 10% (v/v) aqueous ethanol, and sunflower oil. After a storage period of 429 days from 155 to 584 days, BFDGE, a prohibited chemical by the European legislation, was not detected in any samples by high-performance liquid chromatography with fluorescence detection. However, BADGE, BADGE.H2O, BADGE.HCl.H2O, and BADGE.2H2O were found at levels below the European Union limits. Conducted analyses using Fourier transform infrared spectroscopy in attenuated total reflectance mode showed that epoxy–phenolic lacquers may be used as food container coatings. Additional work using atomic force microscopy did not reveal the signs of degradation of the inner coatings in contact with the simulants. [ABSTRACT FROM AUTHOR]

The foaming behavior of a diglycidyl ether of bisphenol-A (DGEBA) epoxy resin-anhydride hardener system at varying accelerator (tertiary amine) concentration, using chemical foaming agent (CFA), was investigated. The microstructure of foams revealed a smaller cell size, higher cell density, and more homogeneous distribution of cells at higher curing rate by varying accelerator contents, whereas not the same by varying foaming temperatures. The curing of epoxy system was studied by a differential scanning calorimetry, while the decomposition process of CFA was investigated by the foaming pressure measurement. Kinetics data showed that the addition of CFA in epoxy system produced obvious influence on the curing process of epoxy mixture; meanwhile, the decomposition reaction of CFA in epoxy system showed an autocatalytic behavior, which can be well predicted by Šesták-Berggren equation. Reaction rate constants of the curing of epoxy foaming system ( k ) and the degradation of CFA ( k ) were calculated, and the competition between these two simultaneously occurring reactions was expressed by the kinetic parameter k / k . The high specific value of k / k , which can be tuned by both accelerator concentration and foaming temperature, indicated that the curing rate was much higher than degradation rate of CFA. By further accelerating the curing rate in the foaming stage, a new two-step method was introduced to fabricate microcellular epoxy foam at relatively low viscosity. [ABSTRACT FROM AUTHOR]

Two similar macrocycles protoporphyrin IX and zinc protoporphyrin IX (ZPP) have been used as cross-linking agents for curing the epoxy resin of bisphenol A diglycidyl ether (BADGE, n = 0). The enthalpies and the activation energies of the esterification reaction of the 2 systems are very close to each other. However, the temperature of the minimum in the differential scanning calorimetry thermogram is 38°C lower for BADGE (n = 0)/ZPP, thus requiring a less energy expenditure for curing the system. By the contrary, the enthalpy and activation energies for the etherification reaction are lower and higher, respectively, for BADGE (n = 0)/ZPP suggesting that the zinc ion affects it, although the involved mechanism is unknown. [ABSTRACT FROM AUTHOR]

Acetylene-terminated benzoxazines (A-BOZs) were copolymerized with bisphenol A diglycidyl ether (DGEBA) epoxy resin to improve their processibility and adhesive properties without sacrificing much thermal performance. The three possible polymerization reactions for A-BOZs/DGEBA blends were monitored by differential scanning calorimetry (DSC) analysis and Fourier transform infrared (FTIR) spectroscopy. The rheological characterization showed that a much wider processing window could be obtained for A-BOZs/DGEBA because of the dilution effect of the epoxy. The lap shear strength of A-BOZs improved significantly with the incorporation of DGEBA. Furthermore, the cured blends also showed good heat and water resistance properties and high glass transition temperature (Tg). [ABSTRACT FROM AUTHOR]

Waterborne nanoemulsion of diglycidyl ether of bisphenol A type epoxy resin (DGEBA) with droplet size of around 124 nm was prepared by using an ultrasonic-assisted supercritical carbon dioxide (scCO 2 ) technique in an autoclave reactor at a low temperature (32 °C). A view cell positioned in-line with the ultrasonic probe allowed observation of the emulsification process. From the image analysis and droplet size measurement, the influence mechanisms of the ultrasonic power, the degree of mixing of scCO 2 with DGEBA, the adding amount of emulsifier, and the system pressure on emulsification process and emulsion droplet size were investigated. In the emulsification process, scCO 2 penetrated into the mixture and absorbed on the DGEBA molecular. The interactions between CO 2 and the functional groups of DGEBA reduced the chain-chain interactions of polymer segments and therefore efficiently reduced the viscosity of DGEBA at a low temperature. Meantime, the cavitation and acoustic streaming of ultrasound provided a shear force for the nanoemulsification and a disturbance force for the homogeneity of the emulsion. Therefore, the combination of scCO 2 and ultrasonication made it possible to prepare a long-term stable nanoemulsion under a low temperature. This ultrasonic-assisted scCO 2 emulsification method provides an efficient and solvent-free process for the preparation of waterborne nanoemulsions of, for example, some heat-sensitive and water-insoluble active substances at low temperature. [ABSTRACT FROM AUTHOR]

It is demonstrated that the heat of epoxy cure as measured by isothermal differential scanning calorimetry (DSC), as commonly calibrated by the heat of fusion of an indium standard, is consistently low as compared to methods “directly” calibrated by Joule heating [i.e., isothermal microcalorimetry (IMC)]. The discrepancy between measurement techniques is shown to be on the order of 15% for low thermal conductivity epoxy thermosets. In addition to direct comparisons between DSC and IMC measurements during epoxy polymerization, indium samples embedded in cured epoxy were studied to determine if the DSC was able to accurately capture the total heat of fusion through the polymeric insulating layer. It is found that the indium heat of fusion measured by DSC is lower when the indium is embedded in epoxy than when the indium is in direct contact with a steel sample pan. The fraction of the indium heat of fusion detected through the epoxy insulation by the DSC cell is comparable to the fraction of the heat of reaction detected by DSC during epoxy cure, as determined from the DSC-IMC comparison. It is concluded that the heat flow detected by DSC during epoxy cure must be scaled by a factor of 1.18 in order to accurately portray the full heat of reaction under the conditions used in this work. It is argued that the difference found between DSC and IMC is in reasonable agreement with qualitative heat transfer calculations and with previous thermal conductivity measurement of polymers via DSC. The specific scaling factor is anticipated to depend on the material studied, on the pan type, on the sample geometry, on the purge gas details, and on the instrumentation. Instruments used in this work include a Q2000 DSC and a TAM Air IMC (both TA instruments). The epoxy was diglycidyl ether of bisphenol A (DGEBA) cured with diethanolamine (DEA). [ABSTRACT FROM AUTHOR]

The UV-curing of epoxy monomers by cationic photopolymerization is a powerful method for the production of polymer materials. The limit of film thickness in cationic photopolymerization of epoxy monomers has been recently overcome by introducing a novel radical induced cationic frontal polymerization (RICFP) system within this research group. The possibility to cure epoxides in bulk by UV-light promoted here presents the novel approach to photocured composites. In the present work, the recently established RICFP system is applied on SiO2-filled epoxy formulations based on bisphenol-A diglycidyl ether. The influence of filler content on frontal propagation is examined in RICFP experiments. The composite materials are also investigated by dynamic mechanical thermal analysis to determine mechanical properties of the frontally polymerized products. [ABSTRACT FROM AUTHOR]

A fluorescence polarization (FP) assay for the simultaneous determination of bisphenol A (BPA), bisphenol F (BPF), bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) was developed. The method was based on the competition between bisphenols (BPs) and fluorescein-labeled dexamethasone derivative (Dex-fl) for mouse peroxisome proliferator-activated receptor α ligand binding domain (mPPARα-LBD). A recombinant soluble protein derivative mPPARα-LBD* was prepared, then in vitro binding of 4 BPs to mPPARα-LBD* was investigated. Fluorescence polarization assay showed that these compounds exhibited different binding potencies with mPPARα-LBD*. Additionally, molecular dynamics simulations were performed to further understand the mechanism of BPs binding affinity for mPPARα-LBD*. Docking results elucidated that the driving forces for the binding of BPs to mPPARα-LBD* were predominantly dependent on hydrophobic and hydrogen-bonding interactions. Comparison of the calculated binding energies vs. experimental binding affinities yielded a good correlation (R 2 = 0.7258). The proposed method has potential for multi-residue detection of BPA, BPF, BADGE, and BFDGE. [ABSTRACT FROM AUTHOR]

ABSTRACT We investigated the dynamics of phase separation in a bisphenol A diglycidyl ether (BADGE)-poly(trimethylene terephthalate) (PTT) blend in this study, along with its effects on the long-term mechanical properties of the blend. BADGE-PTT blends with 4,4′-diaminodiphenyl sulfone were prepared by a conventional melt-mixing technique followed by curing at 180 °C for 4 h. PTT is a rapidly crystallizing polymer because of its unique stereochemistry. The crystalline fraction of PTT is incompatible with BADGE, whereas the amorphous fractions are miscible. Similarly, the blend of BADGE and PTT represented a system with a strong dynamic asymmetry. We examined the effect of the curing (crosslinking) of BADGE in the system discussed previously, with a special emphasis on the viscoelastic properties and long-term mechanical properties because they are extremely important in tuning these materials for various high-performance applications in the aerospace industry. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45059. [ABSTRACT FROM AUTHOR]

A reaction between a linear polypropylene functionalized with maleic anhydride (PPg) and epoxy resin (bisphenol A diglycidyl ether) was carried out on the molten state to generate long-chain branches (LCB) in the molecular structure of the PPg. Concentrations of epoxy resin (ER) of up to 3.15 wt% were employed to obtain different levels of branching. FTIR spectroscopy analysis indicates that during the reaction, anhydride groups in PPg are consumed and new ester groups are formed. The presence of branches was verified using multiple-detection size-exclusion chromatography and rheology. The degree of long-chain branching induced in PPg augments with increasing concentration of ER. Furthermore, the materials modified with higher content of ER display gel-like behavior. The long-chain branched polymers also display thermo-rheological complexity. Thermal characterization studies show that LCBs have a nucleating effect during crystallization and cause the augment of the crystallization activation energy of PPg. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the reinforcement performance of the modified silicas prepared through the incorporation of 3-aminopropyltriethoxy silane (AP) and further reaction of bisphenol A diglycidyl ether (BG) to styrene-butadiene/butadiene rubber (SBR/BR) compounds was investigated to discuss the effect of surface and networked states on the properties of silica-filled rubber compounds. The adjustment of the ratio of BG to AP varied the surface and networked states of silica. The amino and glycidyl groups dispersed on the silica and the networks formed on/between silica particles considerably influenced the properties of SBR/BR compounds reinforced with the modified silicas. The presence of amino group increased viscosity of the rubber compounds due to the attrition between rubber chains and silica particles, while the entanglement of rubber chains with the networks successfully improve both wet traction and rolling resistance, without sacrificing the fundamental properties of the rubber compounds, even though no coupling agents were applied. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44893. [ABSTRACT FROM AUTHOR]

A novel and cost-effective approach towards the modification of epoxy matrix has been developed using recycled polyurethane for the first time without sacrificing any of the intrinsic properties of the resin. Polyurethane, recycled from waste foam by glycolysis process (RPU), was found to be very effective in improving the properties of the thermosetting resin based on Diglycidyl ether of bisphenol-A (DGEBA). The effect of the addition of polyurethane on the mechanical and viscoelastic properties was analyzed and the morphological changes with the inclusion of varying concentrations of RPU were examined by High Resolution Transmission Electron Microscopy (HRTEM). All the blends remained transparent, even after curing by a reaction induced phase separation process (RIPS) of the epoxy phase and hence suggests the development of microphase separation and nanostructure formation. The nanoscale morphology is very clear even with 15 phr concentration of the recycled polyurethane. The morphology at high concentration (40 phr) of RPU under HRTEM showed very distinct ordered interpenetrating network (IPN) like formation and a phase in phase morphology. The size of the dispersed RPU particles varied from 32 to 80 nm as the concentration of RPU varied from 15 to 40 phr in the epoxy phase. This is the first report where nanoscale morphology development by viscoelastic phase separation (VPS) process. The tensile strength values varied from 57 MPa for neat epoxy to 68 MPa for the 40 phr blend. The fracture toughness was increased by 83% for the addition of 40 phr RPU. The recycled PU can be considered as excellent low cost reinforcing filler for epoxy resin where strength and modulus of epoxy resin could be improved simultaneously with an increase of fracture toughness. [ABSTRACT FROM AUTHOR]

The kinetics of polymerization of Bisphenol-A diglycidyl ether (DGEBA), a well-known epoxy resin, with two ionic amines 1-(3-aminopropyl)-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([apbim][NTf2]) and the tetrabutylammonium leucine ([N4444][Leu]) have been studied with the use of differential scanning calorimetry (DSC) and broadband dielectric spectroscopy (BDS) at various temperatures. We found many fundamental differences between the progress of this reaction with respect to the classical system (curing of epoxy resin with ordinary nonconducting hardeners). One of the most significant differences is related to the mechanism of polymerization. It is worthwhile to mention that usually the autocatalytic model is used to describe the curing of DGEBA with ordinary amines. However, herein, the kinetic curves followed a clearly exponential shape characteristic of first-order kinetics. We claim that the change in mechanism of polymerization is related to the presence of a conducting amine that acts as both the substrate and the catalyst of this specific chemical conversion. Also, it is presented that the pace of the reaction only weakly depends on temperature, which is reflected in the relatively low activation energy. On the other hand, the degree of monomer conversion stays around 45%-70% as typically reported for the polymerization of DGEBA with nonconducting hardeners. In addition, we measured the time evolution of dc conductivity as the reaction proceeded and observed that a change in this parameter correlates very well with the monomer conversion in contrast to the reaction of nonconducting systems. Finally, ionic conductivity of the resulted cured samples was investigated and found to be quite significant at the glass transition temperature with respect to other polymerized ionic liquids. [ABSTRACT FROM AUTHOR]

The subject of composite materials with reinforced filler has been studied recently. This study to improve both the dielectric and structural characteristics of diglycidyl ether of bisphenol a (DGEBA) focused on the appropriate use (from 5% to 60 wt%) of pozzolan filler mechanically grinded to obtain a very fine particle size ( Ø < 10 μm) and area surface of 23.5 m2 g−1. The dielectric properties were investigated at great filler concentrations by weight. Epoxy microcomposite samples with a good dispersion of nanoparticles in the epoxy matrix were prepared and experiments were performed to measure the capacitance ( C), the electrical resistance ( R), and impedance ( Z) as a function of frequency (1 kHz-10 kHz). Measurements were made using dielectric spectroscopy over the temperature range 25-80°C. Using the scanning electron microscope (SEM), the morphologies and structure of the surface and fracture surfaces of Pozzolan/DGEBA composites were observed. POLYM. COMPOS., 38:324-331, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The total syntheses of (−)-rotenone and (−)-dalpanol have been achieved by a group-selective, stereospecific 1,2-shift of an epoxy alcohol and SNAr cyclizations. Three oxacycles are constructed, thus illustrating a versatile synthetic route to various rotenoids. [ABSTRACT FROM AUTHOR]