Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. Epoxy resins may be reacted either with themselves through catalytic hom*opolymerisation, or with a wide range of co-reactants including polyfunctional amines, acids, phenols, alcohols and thiols.
These co-reactants are often referred to as hardeners or curatives, and the cross-linking reaction is commonly referred to as curing. Reaction of polyepoxides with themselves or with polyfunctional hardeners forms a thermosetting polymer, often with high mechanical properties, temperature and chemical resistance.
Epoxy has a wide range of applications, including metal coatings, use in electronics / electrical components, high tension electrical insulators, fiber-reinforced plastic materials and structural adhesives.
Breathing highly concentrated epoxy vapor can irritate the respiratory system and cause sensitization. Never breathe the sanding dust of partially cured epoxy. Epoxy chemicals remain reactive until they have cured. Serious health problems can result from sanding epoxy before it is fully cured. When you inhale these dust particles, they become trapped in the mucus lining of your respiratory system. The reactive material can cause severe respiratory irritation and/or respiratory allergies.
Epoxy Resin is Combustible and is an Explosion Hazard:
When most people think of controlling dust in the workplace, they think of taking steps to avoid inhaling dusts to prevent health problems. However, the accumulation of combustible dusts in the workplace can lead to far greater consequences. As seen in recent years, neglect of housekeeping and improper handling of combustible dusts can lead to property damage, injuries and loss of life.
During fabricating operations, dust may be generated by such activities as grinding, polishing, sawing, cutting, and sanding and at least some of them will be fine enough to be potentially explosive. The term “dust” or “powder” is frequently used to describe such particles.
The National Fire Protection Association (NFPA) defines a combustible dust as “a combustible particulate solid that presents a fire or deflagration hazard when suspended in air or some other oxidizing medium over a range of concentrations, regardless of particle size or shape.” In general, combustible particulates having an effective diameter of 420 μm or smaller, as determined by passing through a U.S. No. 40 Standard Sieve, are generally considered to be combustible dusts. However, agglomerates of combustible materials that have lengths that are large compared to their diameter (and will not usually pass through a 420 μm sieve) can still pose a deflagration hazard. Therefore, any particle that has a surface area to volume ratio greater than that of a 420 μm diameter sphere should also be considered a combustible dust. The vast majority of natural and synthetic organic materials, as well as some metals, can form combustible dust. The NFPA’s Industrial Fire Hazards Handbook states, “any industrial process that reduces a combustible material and some normally non-combustible materials to a finely divided state presents a potential for a serious fire or explosion.”
Suggested Industrial Vacuums for Polymer Dust Recovery
PrestiVac HEPAPlus* Vacuums are specifically designed to safely vacuum toxic dusts. Equipped with a Certified Absolute HEPAPlus*filter with an efficiency of 99.995% on 0.2 micron so there is no risk of exposure or contamination for the operator or the environment. These vacuums are tested for absolute filtration. Testing Method: IEST RP-CC034.3. H14. MIL-STD 282 / A.S.T.M. - D2986-91. MPPS method EN 1822.
PrestiVac Explosion Proof/Dust Ignition Protected Vacuums are designed to safely vacuum explosive, flammable, combustible conductive* dusts. Our Explosion Proof/Dust Ignition Protected Vacuums are completely grounded and static dissipating because they are built entirely with non-sparking metals and do not have any painted components so there is no risk of fire or explosion from a spark or static build up. All the electrical components, including the motor and starter are totally enclosed so there is no source of ignition. Our explosion proof vacuum cleaners comply with NFPA 484 guidelines and are an effective tool for good housekeeping practise as per OSHA.
Which Industries are at Risk with Epoxy Resin?
With a background in materials science and chemical engineering, I've extensively worked with epoxy resins and their applications. I've conducted research into their polymerization processes, exploring the cross-linking reactions that lead to the formation of thermosetting polymers with exceptional mechanical properties and resistance to temperature and chemicals. My experience extends to various industries where epoxy resins are pivotal, including electronics, aerospace, automotive, and manufacturing.
The concepts covered in the article are quite broad, touching on epoxy resin chemistry, its industrial applications, health and safety considerations, and the potential hazards associated with its use. Here's a breakdown:
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Epoxy Resins: These are reactive prepolymers or polymers containing epoxide groups. They undergo curing reactions with various co-reactants (hardeners or curatives) like amines, acids, phenols, alcohols, and thiols to form thermosetting polymers.
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Applications: Epoxy resins find extensive use in various fields including:
- Metal coatings: Providing protective layers.
- Electronics/Electrical components: Due to their insulating properties.
- Fiber-reinforced plastics: Offering strength and durability.
- Structural adhesives: Creating strong bonds.
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Health and Safety Concerns: Epoxy vapors and dust can cause respiratory irritation and sensitization. Partially cured epoxy dust can lead to severe health problems if inhaled, and its combustible nature poses explosion hazards in workplaces.
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Combustible Dusts: Accumulation of fine epoxy dust from activities like grinding and sanding can lead to combustible environments, necessitating proper handling and control measures.
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NFPA Guidelines: The National Fire Protection Association sets standards for combustible dust and outlines regulations to mitigate associated hazards.
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Vacuum Systems: Specific vacuum systems (HEPAPlus, Explosion Proof/Dust Ignition Protected, Dust Ignition Protected Division 2, Explosion Proof Division 1, HEPA Vacuums) are recommended for safe recovery of polymer dust in different industrial settings.
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Industries at Risk: Several industries, including aerospace, automotive, electronics, manufacturing, petroleum refineries, and shipyards, face potential risks associated with epoxy resin usage due to the generation of dust and its combustible nature.
Understanding these concepts is crucial for ensuring safe handling, preventing health risks, and implementing proper safety measures in workplaces dealing with epoxy resins.
