Unstable - may polymerize in the absence of stabilizer. May be stabilized with, or contain small amounts of, diethylene glycol monomethacrylate, di(ethylene glycol)dimethacrylate, methacrylic acid. Incompatible with strong oxidizing agents, free radical initiators, peroxides, steel. Closed containers may explode if heated due to runaway polymer
2-Hydroxyethyl methacrylate is used for preparation of hydrophilic polymers for biomedical devices.
정의
2-Hydroxyethyl methacrylate is an enoate ester that is the monomethacryloyl derivative of ethylene glycol.
일반 설명
2-Hydroxyethyl methacrylate (HEMA) is biocompatible in nature. Polymeric hydrogel scaffold can be produced by polymerizing HEMA in water.
위험도
30% grade (with xylene): Flammable, moderate fire risk.
환경귀착
2-Hydroxyethyl methacrylate's production and use in acrylic resins, enamels, and as a binder for non-woven fabrics may result in its release to the environment through various waste streams. If released into the air, a vapor pressure of 0.126 mm Hg at 25 °C indicates that 2-hydroxyethyl methacrylate will exist solely as a vapor in the ambient atmosphere. Vapor-phase 2-hydroxyethyl methacrylate will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 16 hours. If released to soil, 2-hydroxyethyl methacrylate is expected to have very high mobility based upon an estimated Koc of 43. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 4.6X10-9 atm-cu m/mole. 2-Hydroxyethyl methacrylate is not expected to volatilize from dry soil surfaces based on its vapor pressure. If released into water, 2-hydroxyethyl methacrylate is not expected to adsorb to suspended solids and sediment in the water column based on the estimated Koc. 2-Hydroxyethyl methacrylate reached 92-100% of its theoretical BOD in 2 weeks using an activated sludge inoculum. Volatilization from water surfaces is not expected to be a necessary fate process based on this compound's estimated Henry's Law constant. An estimated BCF of 1.3 suggests the potential for bioconcentration in aquatic organisms is low. Hydrolysis of 2-hydroxyethyl methacrylate may be a significant process under basic conditions based upon a hydrolytic half-life of 4 hours at pH 11 for the structurally similar butyl acrylate; half-lives for butyl acrylate at pH 7, 8, and 9 were 4 years, 150 days, and 15 days, respectively. Occupational exposure to 2-hydroxyethyl methacrylate may occur through inhalation and dermal contact with this compound at workplaces where 2-hydroxyethyl methacrylate is produced or used. The general population may be exposed to 2-hydroxyethyl methacrylate via inhalation or dermal contact with acrylic resins or enamels containing this compound.
Purification Methods
Dissolve the ester in water and extract with n-heptane to remove ethylene glycol dimethacrylate (checked by gas-liquid chromatography and by NMR) and distil it twice under reduced pressure [Strop et al. J Phys Chem 80 694 1976]. [Beilstein 2 IV 1530.]
