we live in today. [22] The European Chemicals Agency has added BPA to the Candidate List of substances of very high concern (SVHC), which would make it easier to restrict or ban its use in future. [8], Usually, the addition of acetone takes place at the para position on both phenols, however minor amounts of the ortho-para (up to 3%) and ortho-ortho isomers are also produced, along with several other minor byproducts. Bottle producers have largely switched from polycarbonate to polypropylene and there is some evidence that BPA exposure in infants has decreased as a result of this. The ACC mark, Responsible Care, the hands logo mark, CHEMTREC, TRANSCAER, and americanchemistry.com are registered service marks of the American Chemistry Council, Inc. May also be known as: Polycarbonate, Epoxy Resins. Physical State: Powder. [103], BPA is an environmental contaminant of emerging concern. Diglycidyl ether of bisphenol A epoxy resin (EPOLAM 2017), and 3-minomethyl-3,5,5 trimethylclohexylamine hardener (EPOLAM 2018). Bisphenol A diglycidyl ether (DGEBA) can be called a small-molecule adhesive. TM 332 epoxy resin (Dow Chemical, Midland, TX, USA) with the epoxy group content of 24.6%-25.1% and epoxy equivalent of 171-175 which is referenced as DGEBA and with ERISYS Resorcinol . NIEHS offers a broad range of job opportunities, career enhancement programs, and research training grants and programs in environmental health sciences and administration. Copolymer epoxy resins were prepared using a two-step process in which 10, 30 and 50% of bisphenol-A was replaced with liquefied bamboo. fatty acid dimers, +undefined-86-13650506873 +undefined-86-13650506873. FDAs Studies. This group may lie within the body of the molecule but is usually terminal. Epoxy Composites: Additives for High Performance, Epoxy Resins: A to Z Technical Review of Thermosetting Polymer, Synthesis of Epoxy Monomer from Bisphenol A and Epichlorohydrin, Be the first to comment on "Epoxy Resins: A to Z Technical Review of Thermosetting Polymer", carboxyl-terminated butadiene acrylonitrile copolymer (CTBNs), Powdered metals to improve electrical and thermal conductivity, Silica for cost reduction, and strength enhancement, Talc and calcium carbonate cost reduction, Carbon and graphite powders to increase lubricity, Particle characteristics (size, share, surface area), Extremely strong and good flexural strength, The hardener and the temperature determine epoxy resin cure time, Resistant to wear, cracking, peeling, corrosion and damage from chemical and environmental degradation, Has a bonding strength of up to 2,000 psi, Generally, costs slightly less than epoxy resin, Off-gases VOCs and has strong, flammable fumes, Bonding strength of polyester resin is generally less than 500 psi, Once cured, polyester resin is water permeable, meaning water can pass through it eventually, Better adhesive properties (the ability to bond to the reinforcement or core), Superior mechanical properties (particularly strength and stiffness), Improved resistance to fatigue and micro cracking, Reduced degradation from water ingress (diminution of properties due to water penetration), Increased resistance to osmosis (surface degradation due to water permeability), Natural oil-based (soybean, linseed, castor). (2013) A new approach to synergize academic and guideline-compliant research: the CLARITY-BPA research program. [66][67][68] The primary source of human exposure is via food, as epoxy and PVC are used to line the inside of food cans to prevent corrosion of the metal by acidic foodstuffs. Free of claims are used to indicate that a product does not contain a certain material, such as BPA, but they can sometimes be misleading. 2012 May-Jun;34(3):331-7. l) Patterson TA, Twaddle NC, Roegge CS, Callicott RJ, Fisher JW, Doerge DR. Concurrent determination of bisphenol A pharmacokinetics in maternal and fetal rhesus monkeys. [48] BPA is a major component of several high-performance plastics, the production of these is low compared to other plastics but still equals several thousand tons a year. [91], BPA has been detectable in the natural environment since the 1990s and is now widely distributed. [70][71] The body first converts it into more water-soluble compounds via glucuronidation or sulfation, which are then removed from the body through the urine. Toxicol Sci. Published September 2022. [96] The solubility of BPA in water is low (~300g/ton of water)[2] but this is still sufficient to make it a significant means of distribution into the environment. Dianin in 1891. Bisphenol A was first synthesized by A.P. FDA has amended its regulations to no longer provide for the use of BPA-based polycarbonate resins in baby bottles and sippy cups. The manufacturing of epoxy resins and vinyl ester resins account for 25-30% of BPA use. Studying this sort of longterm, lowdose interaction is difficult, and although there have been numerous studies, there are considerable discrepancies in their conclusions regarding the nature of the effects observed as well as the levels at which they occur. Food cans and other metal containers may be coated with epoxy resin linings made with BPA to help prevent direct food contact with metal, which helps protect food from contamination and spoilage. Some are conducted according to internationally recognized standards that ensure methodological and statistical reliability, and others are not. Formula: CAS CAS: Chemical Abstract Service Registry Number . 2010 Sep 1;247(2):158-65. d) Doerge DR, Twaddle NC, Vanlandingham M, Brown RP, Fisher JW. BPA is also found in epoxy resins, which act as a protective lining on the inside of some metal-based food and beverage cans. [90] Different expression of ERR- in different parts of the body may account for variations in bisphenolA effects. Properties form viscous liquid Quality Level 100 composition Epoxide equivalent weight, 172-176 [105] Regardless, the existing data shows the effects of BPA on wildlife to be generally negative. Transfer to a pear-shaped separatory funnel to separate the liquid, continue washing and separating with deionized water until the solution turns to neutral from alkaline. [1]U.S. Food and Drug Administration, Draft Assessment of Bisphenol A for Use in Food Contact Applications, 14 August 2008. The chemical formula of Bisphenol A isC15H16O2. If youve ever read a news article or blog post about chemicals, you may have heard the oft-cited claim that there are 84,000 chemicals in commerce but only 200 of these have been tested for safety. Find out about the exciting discoveries being made by NIEHS and NIEHS-supported researchers that are helping to improve health and save lives. Polym Adv Technol 2009; 20: 194-208. . Epub 2014 Feb 4. c) Doerge DR, Twaddle NC, Vanlandingham M, Fisher JW. 2014 May;139(1):174-97. doi: 10.1093/toxsci/kfu022. NIEHS has a goal to ensure job opportunities and career enhancements programs for both our work force and our community. Sign in to download full-size image Parents and caregivers can make the personal choice to reduce exposures of their infants and children to BPA: This content is available to use on your website. One reason people may be concerned about BPA is because human exposure to BPA is widespread. Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. A large number of ketones undergo analogous condensation reactions. Copyright 2022 ChemicalBook. It is also a component in metal can coatings, which protect the food from directly contacting metal surfaces. According to the ratio of raw materials, the reaction conditions and adopt the same method can be obtained with different degrees of polymerization of low molecular weight viscous liquid and high . Federal government websites often end in .gov or .mil. The review was documented in four memoranda and their attachments: Strong consumer and scientific interest in the safety of BPA has prompted FDA to support additional studies to provide further information and address apparent inconsistencies in the scientific literature about BPA. Phenol is a man-made chemical, although it is also found naturally in animal waste and decomposing organic material. Poly(Bisphenol-A-co-epichlorohydrin) (PBE) is an epoxy based resin that is a phenoxy polymer derived from bisphenol A and epichlorohydrin. Its optical clarity allows direct observation of blood or other fluids to monitor proper flow. . [4] The studies were evaluated for their relevance for regulatory hazard and/or risk assessment. [2]FDA Science Board Subcommittee on Bisphenol A. BPA is an industrial chemical used to make a hard, clear plastic known as polycarbonate. . The oligomers may vary in molecular weight from 340 and higher. Toxicol Appl Pharmacol. This petition demonstrated, from publicly available information and information collected from industry sources, that the use of BPA-based epoxy resins as coatings in packaging for infant formula had been abandoned. Polycarbonate plastic also is used to make housings for electronic products such as cell phones and laptops, as well as optical discs such as CDs and DVDs. Uses of all substances that migrate from packaging into food,. The viscosity of the PEOs obtained in present and earlier papers was compared with conventional low molecular weight bisphenol A based epoxy resin D.E.R. Epoxy is the family of basic components or cured end products of epoxy resins.Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. [21] BPA has been investigated by public health agencies in many countries, as well as by the World Health Organization. 25085-99-8) Suppliers Limit companies to: Worldwide USA China India EMAIL INQUIRY to 13 suppliers BOC Sciences | Address: Ramsey Road, Shirley, New York 11967, USA https://www.bocsci.com | Send Inquiry | Phone: +1- (631)-485-4226 BOC Sciences is a brand of BOCSCI Inc. This process, also known as a one-step process, is commonly used for the preparation of low and medium molecular weight bisphenol A epoxy resins. Polyols can be compounds such as 1,4-butanediol. These studies also addressed questions about how long it takes for the body to dispose of BPA. Epoxy resins are typically formed by the reaction of compounds containing at least two active hydrogen atoms (polyphenolic compounds, diamines, amino phenols, heterocyclic imides and amides, aliphatic diols, etc.) General description. BPA is one of the most thoroughly tested chemicals in use today and has a safety track record of more than 50 years. The primary source of exposure to BPA for most people is through the diet. Make any industrial chemical reactions run smoothly with the organic intermediate compounds available at Alibaba.com's chemical store. It is found in various products including shatterproof windows, eyewear, water bottles, and epoxy resins that coat some metal food cans, bottle tops, and water supply pipes. [74] It binds to both of the nuclear estrogen receptors (ERs), ER and ER. [9][10] The remaining 5% is used as a major component of several high-performance plastics, and as a minor additive in PVC, polyurethane, thermal paper, and several other materials. Furthermore, composite . Alternatively, and to a much lesser extent, BPA may be ethoxylated and then converted to its diacrylate and dimethacrylate derivatives (bis-EMA, or EBPADMA). Bisphenol A was investigated in the 1930s during the search for synthetic estrogens. The subchronic study was designed to characterize potential effects of BPA in a wide range of endpoints, including prostate and mammary glands, metabolic changes, and cardiovascular endpoints. Studies are different, and all are not of the same quality. Before sharing sensitive information, make sure youre on a federal government site. Concerns about the health effects of BPA have led some manufacturers replacing it with other bisphenols, such as bisphenol S and bisphenol F. These are produced in a similar manner to BPA, by replacing acetone with other ketones, which undergo analogous condensation reactions. [5] https://www.regulations.gov/docket/FDA-2010-N-0100. But, lets first start by understanding thermosets. Table 1, Table 2 present the . BPS differentiates from BPA by possessing a sulfone group (SO 2) as the central linker of the . BPA is fairly cheap to produce, as the synthesis benefits from a high atom economy and large amounts of both starting materials are available from the cumene process. Polycarbonate plastic made with BPA is shatter-resistant, lightweight, and has high optical clarity similar to glass. The degree to which BPA leaches from polycarbonate bottles into liquid may depend more on the temperature of the liquid or bottle, than the age of the container. Chemical Economics Handbook. Epoxy resin is based on epichlorhydrin and bisphenol A. [106][107] BPA appears able to effect development and reproduction in a wide range of wildlife,[107] with certain species being particularly sensitive, such as invertebrates and amphibians.[106]. The CLARITY Study, the largest study ever done on BPA and conducted by FDA experts, confirms that BPA is safe, and supports the agencys one word answer to the question: Is BPA safe?: Yes. It belongs to the phenol class of aromatic organic compounds. 2005 2022 American Chemistry Council, Inc. Bisphenol A (BPA) is a chemical used to make polycarbonate plastic. Because of its extreme durability and strength, polycarbonate plastic is particularly useful for making component parts that need to be thin and light, but strong. Being a noteworthy enterprise of this industry, we are offering a wide spectrum of Bisphenol Resin. This early work underpinned the development of epoxy resins, which in turn motivated production of BPA. The .gov means its official. Epoxy resins are made by reacting epichlorohydrin (ECH) and bisphenol A to produce a different chemical substance called bisphenol A diglycidyl ether (also known as BADGE or DGEBA). Bisphenol A (BPA) is an organic synthetic compound with the chemical formula (CH3)2C(C6H4OH)2 belonging to the group of diphenylmethane derivatives and bisphenols, with two hydroxyphenyl groups. Developmental treatment with bisphenol A or ethinyl estradiol causes few alterations on early preweaning measures. [43][44] This is achieved by a reaction with epichlorohydrin under basic conditions. EC number: 500-130-2 [5] Although the reassessments indicated a need to further evaluate a number of endpoints or biological outcomes, the analyses did not recommend any adjustments to BPA levels reported in food at that time. Durable and decorative floorings, such as terrazzo flooring, chip flooring and colored aggregate flooring, are made from epoxy resins. Singapore 069535, 6,6-Dimethyl-2-methylenebicyclo[3.1.1]heptane, BPA. We provide Bisphenol A epoxy resin safety data sheet view and download for free at Echemi.com. Get info of suppliers, manufacturers, exporters, traders of Bisphenol Resin for buying in India. BISPHENOL A EPOXY: is solid at room temperature, in the form of prills, white - peal, white to yellow and with a slight phenolic odour. Use a solvent mixture of petroleum ether and ethyl acetate (volume ratio 3:1) a developing solvent to purify it by column chromatography according to the above procedure to obtain DGEBA. Recently completed a rodent subchronic study [7] intended to provide information that would help in designing a long-term study that is now underway (see below). [26] The utilization of BPA further expanded with discoveries at Bayer and General Electric on polycarbonate plastics. Bisphenol A is an organic synthetic compound used in formulating plastics and epoxy resin. 2013 Jul 1;270(1):45-59. [12][13][14] BPA is a xenoestrogen, exhibiting hormone-like properties that mimic the effects of estrogen in the body. [90] It can also protect it from deactivation from the SERM 4-hydroxytamoxifen (afimoxifene). [9][10] The manufacturing of epoxy resins and vinyl ester resins account for 2530% of BPA use. Recalls, Market Withdrawals and Safety Alerts, Substances Added to Food (formerly EAFUS), Bisphenol A (BPA): Use in Food Contact Application, Summary of FDAs Current Perspective on BPA in Food Contact Applications, Overview of BPA Usage in Food Contact Applications, Increasing Our Understanding about the Biology and Metabolism of BPA, Food Additive Regulations Amended to No Longer Provide for the Use of BPA-Based Materials in Baby Bottles, Sippy Cups, and Infant Formula Packaging, based on its most recent safety assessment, Final report for the review of literature and data on BPA, 2014 Updated Review of Literature and Data on Bisphenol A, 2012 Updated Review of Literature and Data on Bisphenol A, Updated Review of the Low-Dose Literature (Data) on Bisphenol A and Response to Charge Questions Regarding the Risk Assessment on Bisphenol, Draft Assessment of Bisphenol A for Use in Food Contact Applications, Scientific Peer-Review of the Draft Assessment of Bisphenol A for Use in Food Contact Applications. Lactational transfer of bisphenol A in Sprague-Dawley rats. Released in 2018 by the U.S. National Toxicology Program, the data supports FDAs one word answer to the question Is BPA safe?: Yes. [25], In 1934, workers at I.G. Therefore, they are effective adhesion for most substrates such as glass, ceramics, silicon wafers, and polymer materials. The .gov means its official.Federal government websites often end in .gov or .mil. Scientific Peer-Review of the Draft Assessment of Bisphenol A for Use in Food Contact Applications, 31 October 2008. [90] BPA binding to ERR- preserves its basal constitutive activity. bisphenol A type Epoxy resin depending on the molecular weight and degree of polymerization n, the resin is yellow to amber transparent viscous liquid (or solid), the average molecular weight in the production of 300~700, n; 2, softening point below 50 is called low molecular weight epoxy resin (I. E. Soft resin); Molecular weight above 1000, n>2, those having a softening point above 60 C. Some, but not all, plastics that are marked with recycle codes 3 or 7 may be made with BPA. [28][29][30] Subsequent work found that it bound to estrogen receptors tens of thousands of times more weakly than estradiol, the major natural female sex hormone. In particular, infants are considered to be at greater risk,[83] leading to bans on the use of BPA in baby bottles and related products by the US,[84] Canada,[85] and EU[86] amongst others. Based on FDAs ongoing safety review of scientific evidence, the available information continues to support the safety of BPA for the currently approved uses in food containers and packaging. Chemical Name: Hydrogenated Bisphenol A Epoxy Resin CAS No. 2010 Oct 1;248(1):1-11. h) Fisher JW, Twaddle NC, Vanlandingham M, Doerge DR. Pharmacokinetic modeling: prediction and evaluation of route dependent dosimetry of bisphenol A in monkeys with extrapolation to humans. The internal rotation function of the ether bond increases the flexibility of the molecule, and the hydroxyl group enhances the chemical reactivity and the bonding ability, the epoxy group cross-links molecules into a three-dimensional network structure by reacting with a curing agent. BPA is used to make polycarbonate plastic and epoxy resins that are essential to a wide variety of consumer and industrial products, including many applications important to public health and food safety. [105] As such, the precise effects of BPA on the growth, reproduction, and development of aquatic organism is not fully understood. The conclusion is not based simply on the number of studies, but more importantly on their quality and scientific value. Questions & Answers on Bisphenol A Use in Food Contact Applications, Bisphenol A Overview & Response to Petitions, European Food Safety Authority Information on Bisphenol A. .mw-parser-output .ib-chembox{border-collapse:collapse;text-align:left}.mw-parser-output .ib-chembox td,.mw-parser-output .ib-chembox th{border:1px solid #a2a9b1;width:40%}.mw-parser-output .ib-chembox td+td{width:60%}, Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. Plastic containers have recycle codes on the bottom. Alternatively, bisphenol A (BPA) definition is that it is a synthetically obtained colourless crystalline organic compound that occurs in the solid phase belonging to the diphenylmethane group and is soluble in organic solvents but poorly dissolves in water (0.344 % wt. It is also known to exhibit strong endocrine-disrupting ability. Bisphenol A Epoxy Resin (CAS No. Toxicol Lett. [65][24], As a result of the presence of BPA in plastics and other commonplace materials, most people are frequently exposed to trace levels of BPA. Some of this is further reacted with methacrylic acid to form bis-GMA, which is used to make vinyl ester resins. Bisphenol A (BPA) is a chemical building block that is used primarily to make polycarbonate plastics. Reports indicate that it is a minor skin irritant as well, although less so than phenol. bisphenol A: [noun] an industrial chemical compound C15H16O2 that is a component especially of hard plastics (such as polycarbonate) and epoxy resins. . Bisphenol A (BPA) is a chemical produced in large quantities for use primarily in the production of polycarbonate plastics. It is important to note that scientific experts at FDA, and other regulatory bodies, review the full weight of the scientific evidence when making decisions about safety. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely. In addition to receptor binding, the compound has been found to affect Leydig cell steroidogenesis, including affecting 17-hydroxylase/17,20 lyase and aromatase expression and interfering with LH receptor-ligand binding. Comparatively minor amounts of BPA are also used as additives or modifiers in some commodity plastics. Cool the mixture to room temperature; add extractant toluene/water (volume ratio 2:1) and stir it at room temperature for half an hour. What chemicals are in epoxy resin when you consider this? When the low-molecular-weight bisphenol A epoxy resin is continuously reacted with bisphenol A, the obtained bisphenol A epoxy resin has a high polymerization with a relative molecular mass 1400 or more. Toxicol Appl Pharmacol. [99] Regardless, the remaining 29% of BPA will continue through to the environment, with low levels of BPA commonly observed in surface water and sediment in the U.S. and Europe. National Advisory Environmental Health Sciences Council - Day 1. Toxicol Appl Pharmacol. The results of the independent evaluations were released in April 2010, as FDA made the CFSAN report and other relevant information available for public comment. Food Additives & Petitions. NIEHS sponsors and co-sponsors scientific meetings, conferences, and events throughout the year. This results in much lower internal exposure of BPA (i.e., the active form) than what occurs from other routes of exposure such as injection. [36] It may be purified by recrystallisation from acetic acid with water. Due to its especially thick natural consistency, there will commonly be additives and diluents which are added into the Bisphenol-A epoxy formula to enhance workability and adhesion. 506 epoxy resin has been used as an embedding medium for microscopy. Uses of all substances that migrate from packaging into food, including BPA, are subject to premarket approval by FDA as indirect food additives or food contact substances. [34] These are not always removed and are known impurities in commercial samples of BPA. From durable sneakers to waterproof jackets, chemistry plays a big role in all types of outdoor activities. Bisphenol A diglycidyl ether (DGEBA) is a pale yellow liquid epoxy compound formed by the polycondensation of epichlorohydrin (ECH) and bisphenol A (BPA). [11]. It is commonly used in curing fast-drying epoxy resin adhesives. [73] Concern is mostly related to its estrogen-like activity, although it can interact with other receptor systems as an endocrine-disrupting chemical. Surface chemistry the study of chemical . Because of these attributes, polycarbonate is used in a wide variety of common products including digital media (e.g., CDs, DVDs), electrical and electronic equipment, automobiles, sports safety equipment, reusable food and drink containers, and many other products. Abiotic degradation has been reported, but is generally slower than biodegradation. Phenol-formaldehyde resin . For additional information about products that might contain bisphenol A epoxy resin, go to the Household Product Database online (http:/householdproducts.nlm.nih.gov) at the . The site is secure. The study included an in utero phase, direct dosing to pups to mimic bottle feeding in neonates, and employed a dose range covering the low doses where effects have been previously reported in some animal studies, as well as higher doses where estrogenic effects have been measured in guideline oral studies. 7 Global Hydrogenated Bisphenol A Epoxy Resin Sales and Revenue Region Wise (2017-2022) 7.1 Global Sales and Market Share, Region Wise (2017-2022) 7.2 Global Revenue (Revenue) and Market Share . It is prepared by the reaction of two equivalents of phenol with one equivalent of acetone. Developed physiologically based pharmacokinetic models that can be used to predict the level of internal exposure to the active and inactive forms of BPA. BPA is one of the most thoroughly tested chemicals in use today and has a safety track record of more than 50 years. Dianin in 1891. Health concerns have also been raised about these substitutes. In addition, FDA actively supported and participated in the Expert Consultation on BPA convened by World Health Organization and the Food and Agriculture Organization of the United Nations on November 2-5, 2010, in Ottawa, Canada. The CLARITY Study, a 5+ year, multipronged U.S. federal government research program and the largest study ever done on BPA, confirms BPAs safety. Polycarbonate is strong and durable, but over time it may break down from over use at high temperatures. Order: 18 Tons Shandong Near Chemical Co., Ltd. View larger video & image Contact Now Hot Sale Bisphenol a CAS No. It is the lowest molecular weight epoxy resins, and also used as the packaging material for coatings, adhesives, insulating paints, semiconductors, and integrated circuits and other electronic components. BPA is one of the most thoroughly tested chemicals in use today and has a safety track record of more than 50 years. Global production in 2022 is expected to reach 10 million tonnes. Paper recycling can be a major source of release when this includes thermal paper,[9][97] leaching from PVC items may also be a significant source,[93] as can landfill leachate. The site is secure. Learn how outdoors and chemistry work together. [98] Despite its short half-life and non-bioaccumulating character, the continuous release of BPA into the environment causes continuous exposure to both plant[104] and animal life. The molecular weight and the epoxy equivalent weight are controlled by the ratio of epichlorohydrin EPC:BPA. They are produced by the addition of - unsaturated carboxylic acids to epoxy resins. The safety of a food additive is not relevant to FDAs determination regarding whether a certain use of that food additive has been abandoned. High-performance epoxy resins are used to make aircraft, cars, bicycles, boats, golf clubs, skis and snowboards durable, flexible and strong. bisphenol a epoxy resin price are designed to form other substances and play a crucial role in numerous important reactions. 2011 Sep 15;255(3):261-70. e) Doerge DR, Twaddle NC, Vanlandingham M, Fisher JW. tableware. It is alcohol, ketone and ether soluble but presents low solubility in water and carbon tetrachloride. Industrially, a large excess of phenol is used to ensure full condensation; the product mixture of the cumene process (acetone and phenol) may also be used as starting material. 80-05-7 Bisphenol a with Wholesale Price Min. Toxicity evaluation of bisphenol a administered by gavage to sprague dawley rats from gestation day 6 through postnatal day 90. Polycarbonate drinks containers are also a source of exposure, although most disposable drinks bottles are actually made of PET, which contains no BPA. In order to formulate an epoxy adhesive, one must have either bisphenol A or bisphenol F. Bisphenol A (BPA) is generally preferred for its curing properties. [98], In all cases, wastewater treatment can be highly effective at removing BPA, giving reductions of 9198%. [92][101][102] Its half life in water has been estimated at between 4.5 and 15 days, degradation in the air is faster than this, while soil samples degrade more slowly. After their first commercial production in the late 1940s, epoxy resins comprise a wide family of materials today.
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