Epoxy Compounds Research Articles

Effect of a Heterogeneous Network on the Fracture Behavior of Epoxy Resins

Epoxy resins, which possess a three-dimensional network obtained by a curing reaction between epoxy and amine compounds, are in a glassy state at room temperature. They are therefore generally brittle and exhibit rather poor resistance to crack propagation, which is one of the greatest drawbacks for their practical application. To solve this problem, a better understanding of their fracture behavior, which is related to long-term durability, is strongly desired. We herein report on how the extent of network heterogeneity affects the fracture behavior of epoxy resins. Three types of epoxy resins were obtained under different curing conditions, which generated different extents of heterogeneity. The fracture behavior of the three epoxy resins was examined by in situ scanning electron microscopy in conjunction with microbeam X-ray scattering experiments. When the epoxy resin in which a notch was pre-introduced was stretched under a small strain, the internal network structure was deformed, and the extent was more significant with increasing heterogeneity. As further stretching was applied, a crack propagated from the notch. This occurred more easily with increasing heterogeneity. That is, the toughness of the epoxy resins decreased with increasing network heterogeneity. The knowledge obtained here will be useful for understanding and controlling the toughness of epoxy resins.

Evaluation of the incubation period of polymers in cavitation wear by the method of profilometry

The possibility of using profilometry for determining the duration of the incubation period of polymeric materials upon their testing for cavitation wear is considered. Six polymeric materials were tested for cavitation wear: plexiglass, fluoroplastic, low-pressure polyethylene, caprolon, Thordon SXL polymer, and epoxy compound. All the polymers were tested in fresh water kept at 20 ± 3°C, using an ultrasonic magnetostrictive vibrator, the vibration frequency and amplitude of the device horn butt were 22 kHz and 28 μm, respectively. The distance between horn butt and the butt-end surface of the cylindrical polymer sample was set at 0.50 mm. The samples were periodically weighed during testing, the roughness of their worn surface was evaluated, and sample mass loss and arithmetical mean deviation of the assessed profile of its surface were plotted as a function of the test duration. Like the cavitation wear of metals, the cavitation wear of polymers is also characterized by the presence of an incubation period, during which the separation of the wear particles from the sample surface does not take place yet. It is shown, that determination of the incubation period from the dependence of the mass loss vs test duration distinguishes is rather laborious, and, moreover, is accompanied by large errors due to water absorption. The use of profilometry was proposed to shorten the time and increase the accuracy of the determination of the incubation period of the cavitation wear of polymers. The arithmetical mean deviation of the profile of the surface under study is measures periodically during testing for cavitation wear. The duration of the incubation period is determined using the dependence of the arithmetic mean deviation of the wear surface profile on the duration of the cavitation impact by the abscissa of the point, in which the monotony and(or) smoothness of the dependence (plot) is violated.

Organic-inorganic building block of phytic acid intercalated graphene oxide for performance enhancement of plant-derived adhesives

The introduction of 2D graphene into the soybean protein (SP) adhesive is expected to enhance its mechanical performance. However, insufficient binding of the two materials inevitably leads to the resulting composite having limited mechanical strength. Using phytic acid (PA) and a supramolecular self-assembly strategy, hard graphene oxide (GO) was first assembled with PA to form a supramolecular polymer, PA-co-GO, that has a “bricks and mortar” structure as a result of strong non-covalent interactions. PA-co-GO was then further combined with SP in the presence of the long-chain epoxy compound neopentyl glycol diglycidyl ether (NG) to produce a novel biopolymer-based adhesive PA-co-GO/NG/SP. The prepared adhesive has a moisture-insensitive interface as a result of non-covalent/covalent bonds and a “bricks and mortar” microstructure that allows the dissipation of energy, resulting in an enhancement in the water-resistant bonding strength of the material, with a 345% increase in its wet bonding strength compared with the unmodified SP adhesive. Additionally, the combination of the heat shielding of the GO and catalytic carbonization of PA resulted in the adhesive having excellent flame retardant properties. The structure and morphology of the materials were characterized using atomic force microscopy (AFM), dynamic light scattering (DLS), Fourier-transform infrared (FTIR), X-ray photoelectron spectra (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and solid-state 13C NMR. Overall, a new clean route for preparing green high-performance biopolymer-based adhesives is described, with potential applications for sustainable agricultural byproducts.

Multi-dimensional application of quaternary phosphonium salt functionalized fiber with high polarization performance: Efficient adsorption of SDBS and green conversion of CO2

A novel mono-quaternary phosphorus salt functionalized fiber (PANQPSF) was developed as the multifunctional material to simultaneously realize selective removal of sodium dodecyl benzene sulfonate (SDBS) from water and green conversion of CO2. Compared with other adsorption materials and functionalized fibers, PANQPSF exhibits the eminent adsorption performance for SDBS due to its high polarization and hydrophobicity, and the adsorption capacity can reach 5.1 mol mol−1, equivalenting to 1066 mg g−1. And the synergistic adsorption mechanism of electrostatic interaction and lipophilic interaction between PANQPSF and SDBS is proposed. Furthermore, the PANQPSF still keeps excellent adsorption capacity even after 10 cycles. More satisfactorily, PANQPSF is used to catalyze the cycloaddition reaction of CO2 and epoxy compounds. The catalytic mechanism based on the nucleophilicity of Br− and the stabilizing effect of electrostatic interaction is promoted. In summary, the adsorption and catalytic performance prove that PANQPSF is an outstanding material with multi-dimensional applications.

Synthesis of a Sustainable and Bisphenol A‐Free Epoxy Resin Based on Sorbic Acid and Characterization of the Cured Thermoset

AbstractIn the present study, an epoxy compound, 1,2‐epoxy‐6‐methyl‐triglycidyl‐3,4,5‐cyclohexanetricarboxylate (EGCHC) synthesized from sorbic acid, maleic anhydride, and allyl alcohol is proposed. Using commodity chemicals, a bio‐based carbon content of 68.4 % for the EGCHC resin is achieved. When cured with amine hardeners, the high oxirane content of EGCHC forms stiff cross‐linked networks with strong mechanical and thermal properties. The characterization of the epoxy specimens showed that EGCHC can compete with conventional epoxy resins such as DGEBA. A maximum stiffness of 3965 MPa, tensile strength of 76 MPa, and Tg of 130 °C can be obtained by curing EGCHC with isophorone diamine (IPD). The cured resin showed to be decomposable under mild conditions due to the ester bonds. The solid material properties of EGCHC expose its potential as a promising bisphenol A, and epichlorohydrine free alternative to conventional petroleum‐based epoxies with an overall high bio‐based carbon content.

A bio-based epoxy resin derived from syringaldehyde with excellent mechanical properties, flame retardant and high glass transition temperature

Due to increasing environmental concerns, global warming, and the decline of oil reservoirs, the use of bio-epoxy resins derived from sustainable resources is recommended. The development of bio-based epoxy resins with considerable thermal stability, mechanical strength, and appropriate intrinsic flame retardant potential is highly demanded. In this study, a new Schiff-based epoxy monomer, triglycidyl ether of syringaldehyde (SA-TAG-EP), was synthesized from renewable syringaldehyde. After the 4,4′-diaminodiphenylmethane (DDM)-based curing process, an intrinsically flame-retardant resin (SA-TAG-EP/DDM) with C, H, N, and O elements was achieved. SA-TAG-EP/DDM showed higher glass transition temperature (224.9°C) and greater mechanical strength, including a tensile strength of 66.8 MPa and an elongation at break of 3.91%, compared to petroleum-based bisphenol A epoxy thermoset. It also passed the V-0 flammability rating in the UL-94 test and exhibited a 38.5% limiting oxygen index, 48.9% char yield under N2, and a lower peak heat release rate than that of petroleum-based bisphenol A epoxy thermoset. We proposed a simple and sustainable route for the synthesis of Schiff base epoxy compounds from biomass-derived resources, which demonstrates significant mechanical properties and increased flame retardant potential.

Preparation of three new Mn based nanocluster photoinitiators and their application in copolymerization of carbon dioxide and propylene oxide

Carbon dioxide derived copolymers are becoming useful materials in the fields of packaging, construction, household products and auto parts. In which, the polycarbonate and cyclic carbonate can be obtained by ring opening copolymerization with epoxy compounds. Here, three manganese based nanoclusters were prepared and their catalytic copolymerization with CO2 and propylene oxide (PO) was studied. The results show that the catalytic efficiency of nano clusters catalyst G1 is higher than that of K1 and J1. When Mn and Cd atoms are in a certain proportion and R1 or R2 combined action with clusterss, the catalytic efficiency is promoted. Due to the synergistic effect of G1 and R2, the catalytic efficiency is greatly improved. When the external light source with wavelength of 493 nm and 100 W is introduced, the copolymerization efficiency is the highest. For G3, TON increased by nearly two-thirds to 232.3, CPC content was 6.34%, and PPO content reaches 88.47%.

Spectral Analysis of the Effects of Variation in Electrodes' Area for Dielectric Barrier Discharge Actuator

In this work, one configuration was used to study the electrical discharge resulting from the dielectric barrier. This configuration consists of a sheet of epoxy/Al composite with dimensions of 75 mm in length, 25 mm in width, and 3 mm in thickness. This panel is located at the center of the electrodes, so that the distance between each of the electrodes and the plate is 2 mm and plasma is generated at these distances. The relationship between voltage and current with changing the frequency of the equipment as well as changing the area of ​​exposure to the upper electrode or changing its length has been studied. The length of the top electrode varies at 0, 10, 20, 30, and 40 mm from the center of the electrodes producing exposure areas of 1875, 1625, 1375, 1125, 875, and 625 mm2, respectively. Two frequencies of 8 and 9 kHz were applied in this work. The results showed that the discharge current increases linearly with the applied input voltage and with the decrease of the exposure of the upper electrode. Then, the current increases with the stability of the voltage in varying proportions depending on the exposure area and frequency. The plasma generated from this modulation was diagnosed with the exposure area and the fitted frequency. Electron temperature and electron density are calculated using the optical emission spectroscopy technique by Boltzmann and Lorenz, respectively. It can be seen that the temperature, electron density, and plasma frequency increase with the decrease of the exposure area, while the Debye length shows the opposite behavior and this is clear in this formation and high effectiveness at Diagnosis and Reason This formation will be adopted in the surface treatment of the aluminum epoxy compound.

Synthesis and properties of trifluoromethyl organosilicon cycloaliphatic epoxy monomers for cationic photopolymerization

AbstractThe cycloaliphatic epoxy compounds have been widely used as the monomers in cationic photopolymerization and the fluorine‐modified organosilicon materials combine the merits of both organosilicon and organofluorine. In this work, three trifluoromethyl organosilicon cycloaliphatic epoxy monomers with different chain length (CE‐FSin, n = 3, 6, 9) were designed and prepared by using a facile two‐step synthesis and very competitive raw materials. CE‐FSin showed good ability to cationically photopolymerize. The final conversion of the alicyclic epoxy group of CE‐FSin systems reached up to 84.0% under the irradiation for 900 s. The addition of CE‐FSin enhanced the surface water repellency, heat resistance, elongation at break and glass transition temperature (Tg) of the cured film because of the presence of organosilicon chain and trifluoromethyl group of CE‐FSin. The cured film of CE‐FSi3‐0.5% had the largest water contact angle (105.0°), while the cured film of CE‐FSi9‐0.5% had tensile strength of 0.49 MPa and elongation at break of 68.51% that was three folds as that of the blank control. The addition of CE‐FSin had no obvious influences on the adhesion forces of the cured films, but decreased the pencil hardness.

Resorcinol-Derived Vitrimers and Their Flax Fiber-Reinforced Composites Based on Fast Siloxane Exchange.

Natural fiber-reinforced composites are gaining increased interest for their significantly reduced carbon footprint compared to conventional glass or carbon fiber-based counterparts. In this study, natural fibers are used in a resorcinol-based epoxy resin that is thermally reshapable at higher temperatures (>180°C) by using fast exchanging siloxane bonds, catalyzed by 1,5,7-triazabicyclo[4.4.0]dec-5-ene. Stress relaxation times of only about 6s at 220°C can be reached. A resorcinol-based epoxy compound is selected because it can be derived from cellulose, opening ways for more sustainable and reshapable composite materials. In a last step of the research, the low viscosity vitrimer formulation (<200mPas) is applied to make a flax fiber-reinforced composite using an industrially relevant vacuum-assisted resin infusion process. A section of this composite is successfully reshaped, which allows for envisioning a second life for natural fiber-reinforced composites.

Comparison of isoprene chemical mechanisms under atmospheric night-time conditions in chamber experiments: evidence of hydroperoxy aldehydes and epoxy products from NO3 oxidation

Abstract. The gas-phase reaction of isoprene with the nitrate radical (NO3) was investigated in experiments in the outdoor SAPHIR chamber under atmospherically relevant conditions specifically with respect to the chemical lifetime and fate of nitrato-organic peroxy radicals (RO2). Observations of organic products were compared to concentrations expected from different chemical mechanisms: (1) the Master Chemical Mechanism, which simplifies the NO3 isoprene chemistry by only considering one RO2 isomer; (2) the chemical mechanism derived from experiments in the Caltech chamber, which considers different RO2 isomers; and (3) the FZJ-NO3 isoprene mechanism derived from quantum chemical calculations, which in addition to the Caltech mechanism includes equilibrium reactions of RO2 isomers, unimolecular reactions of nitrate RO2 radicals and epoxidation reactions of nitrate alkoxy radicals. Measurements using mass spectrometer instruments give evidence that the new reactions pathways predicted by quantum chemical calculations play a role in the NO3 oxidation of isoprene. Hydroperoxy aldehyde (HPALD) species, which are specific to unimolecular reactions of nitrate RO2, were detected even in the presence of an OH scavenger, excluding the possibility that concurrent oxidation by hydroxyl radicals (OH) is responsible for their formation. In addition, ion signals at masses that can be attributed to epoxy compounds, which are specific to the epoxidation reaction of nitrate alkoxy radicals, were detected. Measurements of methyl vinyl ketone (MVK) and methacrolein (MACR) concentrations confirm that the decomposition of nitrate alkoxy radicals implemented in the Caltech mechanism cannot compete with the ring-closure reactions predicted by quantum chemical calculations. The validity of the FZJ-NO3 isoprene mechanism is further supported by a good agreement between measured and simulated hydroxyl radical (OH) reactivity. Nevertheless, the FZJ-NO3 isoprene mechanism needs further investigations with respect to the absolute importance of unimolecular reactions of nitrate RO2 and epoxidation reactions of nitrate alkoxy radicals. Absolute concentrations of specific organic nitrates such as nitrate hydroperoxides would be required to experimentally determine product yields and branching ratios of reactions but could not be measured in the chamber experiments due to the lack of calibration standards for these compounds. The temporal evolution of mass traces attributed to product species such as nitrate hydroperoxides, nitrate carbonyl and nitrate alcohols as well as hydroperoxy aldehydes observed by the mass spectrometer instruments demonstrates that further oxidation by the nitrate radical and ozone at atmospheric concentrations is small on the timescale of one night (12 h) for typical oxidant concentrations. However, oxidation by hydroxyl radicals present at night and potentially also produced from the decomposition of nitrate alkoxy radicals can contribute to their nocturnal chemical loss.

Sorafenib increases cytochrome P450 lipid metabolites in patient with hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a leading cause of cancer death, and medical treatment options are limited. The multikinase inhibitor sorafenib was the first approved drug widely used for systemic therapy in advanced HCC. Sorafenib might affect polyunsaturated fatty acids (PUFA)-derived epoxygenated metabolite levels, as it is also a potent inhibitor of the soluble epoxide hydrolase (sEH), which catalyzes the conversion of cytochrome-P450 (CYP)-derived epoxide metabolites derived from PUFA, such as omega-6 arachidonic acid (AA) and omega-3 docosahexaenoic acid (DHA), into their corresponding dihydroxy metabolites. Experimental studies with AA-derived epoxyeicosatrienoic acids (EETs) have shown that they can promote tumor growth and metastasis, while DHA-derived 19,20-epoxydocosapentaenoic acid (19,20-EDP) was shown to have anti-tumor activity in mice. In this study, we found a significant increase in EET levels in 43 HCC patients treated with sorafenib and a trend towards increased levels of DHA-derived 19,20-EDP. We demonstrate that the effect of sorafenib on CYP- metabolites led to an increase of 19,20-EDP and its dihydroxy metabolite, whereas DHA plasma levels decreased under sorafenib treatment. These data indicate that specific supplementation with DHA could be used to increase levels of the epoxy compound 19,20-EDP with potential anti-tumor activity in HCC patients receiving sorafenib therapy.

A Curable Underwater Adhesive Based on Poly(propylene oxide) and Tannic Acid Coacervate

Coacervation of poly(propylene oxide) and tannic acid, driven by hydrogen bonding, renders a tacky viscous material that provides an underwater adhesion strength of ∼350–550 kPa on aluminum substrates and also can bond other wet surfaces such as glass, metal, plastic, and porcelain. A curing functionality is achieved by designing a two-component system, using epoxidized poly(propylene oxide)/tannic acid coacervate as part A and amine-terminated poly(propylene oxide) as part B. Aside from underwater bonding, this adhesive can cure underwater through amine-epoxide reactions providing a commercially competitive and waterproof bonding.

Exposure to occupational risk factors is associated with the severity and progression of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) results from a complex interaction between genes and the environment, and occupational exposures are an underappreciated risk factor. Until now, little research attention has been paid to the potential impact of occupational risk factor exposure on the COPD in China. The aim of this retrospective study was to analyze the role of occupational risk factor exposure on the severity and progression of COPD for exploring new prevention strategies for this disease. This study adopted a random cluster-sampling method. Five grade-A tertiary hospitals that met the inclusion criteria were selected as the survey sites, and patients with COPD hospitalized in these hospitals from January 1, 2019, to December 31, 2019, were selected as the research subjects. Data of the patients diagnosed with COPD met the Global Initiative for Chronic Obstructive Lung Disease (2019) criteria and were collected from the computerized medical record databases. Among 4082 investigated COPD patients, 1063 (26%) were found to have occupational risk factor exposure history. The top 3 industries with a large COPD case number and a history of occupational risk factor exposure ranked in the order of agriculture (including farming, forestry, animal husbandry, and fishery), manufacturing, and mining. Further multivariate logistic regression analysis indicated that when setting a low exposure level as a reference, medium and high exposure levels were correlated with the severity of COPD (odds ratio values were 2.837 and 6.201, respectively, P < .05). Linear regression analysis showed that cumulative exposure to occupational risk factors was negatively correlated with the forced expiratory volume in 1-second percentage of COPD patients, with a correlation coefficient of 0.68. Our results indicated that occupational risk factor exposure levels were related to the severity of COPD significantly. The incubation period of COPD in the exposure group was significantly shorter than that in the non-exposure group. To prevent worked-related COPD, special attention and control efforts should be taken to reduce the level of occupational risk factors such as organic dust, irritating chemicals, etc in the work environments, especially in the industries of agriculture, forestry, animal husbandry and fishery, manufacturing, and mining.

USE OF GLYCIDYLOXYMETHYL SUBSTITUTED PHENYL (BENZYL) CYCLOPROPANES IN THE COMPOSITION OF EPOXIDE OLIGOMER ED-20 AS DILUENTS

By the interaction of phenyl (benzyl) substituted cyclopropylcarbinols with epichlorohydrin, the glycidyloxymethyl substituted phenyl(benzyl)cyclopropanes, used as active diluents of epoxide resin ED-20, were synthesized. It found that the addition of the obtained epoxy compounds to the epoxide resin decreases the viscosity of the resin and increases the lifetime of the compositions. The high degree of curing (96-98%) indicates the participation of the synthesized epoxycyclopropanes in the cross-linking processes. Some physical-mechanical characteristics of compounds made with the participation of the synthesized epoxycyclopropanes were established. The improvement of strength and heat-physical parameters of cured compositions in comparison with compositions made without diluents was revealed.

ELASTOMERIC POLYMER COMPOUNDS FOR PRODUCTION OF SPARE PARTS FOR ROBOTIC MILKING SYSTEM

Currently, the import of spare parts of systems, in particular, nipple rubber and elastomeric parts of the milk pump of the milking unit, has been discontinued. In this regard, the problem of developing technologies for manufacturing elastomeric spare parts for milking machines becomes urgent. One of the possible ways of cost-effective production of spare parts in conditions of small-scale production is free casting or low-pressure casting. To implement such technologies, materials with low viscosity (less than 50 pascals per second) are needed, which include polymer compounds. (Research purpose) The research purpose is determining the brands of elastomeric polymer compounds suitable for the manufacture of spare parts for milking machines. (Materials and methods) Used scientific and technical literature as materials for studying, including articles of indexed periodicals and open sources of information containing information about elastomeric polymer compounds. Research methods are the collection, study and comparative analysis of information. (Results and discussion) It was found that among all polymer compounds, epoxy, polyester, polyurethane and silicone compounds were the most widespread in mechanical engineering and the food industry. It was determined that compounds based on polyurethane or silicone are the most suitable for the manufacture of spare parts for milking machines. These materials provide sufficient mechanical characteristics and high elasticity of the manufactured part. It was noted that silicone-based compounds are used for food purposes, which ensures the chemical and biological inertia of the part. (Conclusions) The most suitable brands of elastomeric silicone compounds are Elastolux Platinum 40 and Silagerm 8040. These materials are manufactured in Russia, have low shrinkage, provide high strength and elasticity of the final parts.

Synthesis of network polymers by ring-opening addition reaction of multi-functional epoxy and dithiol compounds

Synthesis of network polymers by ring-opening addition reaction of multi-functional epoxy and dithiol compounds

Solid Particle Erosion of Filled and Unfilled Epoxy Resin at Room and Elevated Temperatures

Solid particle erosion at room and elevated temperatures of filled and unfilled hot-cured epoxy resin using an anhydride hardener were experimentally tested using an accelerated method on a special bench. Micro-sized dispersed industrial wastes were used as fillers: fly ash from a power plant and spent filling material from a copper mining and processing plant. The results showed that the wear of unfilled epoxy resin significantly decreases with increasing temperature, while the dependence on the temperature of the wear intensity at an impingement angle of 45° is linear and inversely proportional, and at an angle of 90°, non-linear. The decrease in wear intensity is probably due to an increase in the fracture limit because of heating. Solid particle erosion of the filled epoxy compounds is considerably higher than that of unfilled compounds at impingement angles of 45° and 90°. Filled compounds showed ambiguous dependences of the intensity of wear on temperature (especially at an impingement angle of 45°), probably as the dependence is defined by the filler share and the structural features of the samples caused by the distribution of filler particles. The intensity of the wear of the compounds at impingement angles of 45° and 90° has a direct and strong correlation with the density and the modulus of elasticity, and a weak correlation with the bending strength of the materials. The data set for determining the correlation between the mechanical properties and the wear included compound filling characteristics and temperature.

Synthesis and characterization of novel bio‐based epoxy polymers derived from natural phenolic compound

AbstractBio‐based epoxy polymer was prepared from cardanol derivatives, epoxy prepolymer and phenalkamine at room temperature without solvent. Chemical structures of cured epoxy polymers were analyzed by FT‐IR and 1H NMR spectroscopy. The drying, physical, thermal, optical, and mechanical properties of the epoxy polymers were investigated in terms of the composition of epoxy and amine compounds, molecular weight of the epoxy prepolymer, and the effect of post‐curing process. The resultant epoxy polymers showed flexible nature, thermal stability (e.g., thermal decomposition temperature of 300°C). Furthermore, the epoxy polymers possessed the anti‐microbial activity against Escherichia coli and Staphylococcus aureus The molecular weight of the epoxy prepolymer also strongly affected the drying property, suggesting that the drying time can be controlled by the molecular weight of the prepolymer. Thermal treatment of the polymers as post‐curing was effective approach to improve the hardness, thermal stability, and mechanical strength. Hence, this cardanol derivatives‐based novel epoxy polymer can be expected as highly green functional epoxy polymers for coating, film and resin applications.

Cytotoksyczność i biokompatybilność kompozytowych, światłoutwardzalnych żywic stomatologicznych

The physical, chemical, and biological properties of restorative dental materials influence the clinical outcome of dental treatment. Methacrylate-based resins are extensively used in everyday dental practice, but accumulating records point to their toxicity. This article reviews the most important experimental data on cell-induced cytotoxicity of composite dental resins, methacrylates and epoxy compounds used to induce polymerization and reduce resin shrinkage. Methacrylate monomers produce reactive oxygen species, induce apoptosis and/or genotoxicity, and affect cell proliferation in culture. There is a need for awareness about the biological risks of these materials. New sensitive methods introduced to the preclinical testing of dental resins may help to highlight specific mechanisms, quantify the biological risk and guide the dentist to select the right biomaterial for dental applications.