Methyl methacrylate vapor pressure

Acute inhalation exposure of dogs to 11,000 ppm led to central nervous system depression, a drop in blood pressure, liver and kidney damage, and death due to respiratory arrest. Mice exposed to 1520 ppm for 2 hours twice daily for 10 days showed no significant histologic changes in heart, liver, kidney, or lungs. In male rats exposed to methyl methacrylate vapor at 116ppm 7 hours/day, 5 days/ week for 5 months, the tracheal mucosa was denuded of cilia and the number of microvilli on the epithelium was reduced. ... 

Methyl methacrylate (MMA) has the formula CH2 = ClCHa) (COOCH3). The vapor pressure of MMA due to its vaporization is estimated by [3] In P(Atm) = 11.79 — 4410/T(K), assuming a constant heat of vaporization. For the depolymerization reaction, the temperature which gives 1 atm of MMA (the product) is 164 C [26]. This temperature establishes the pressure equilibrium constant and therefore the Gibbs fiiee energy for the depolymerization reaction. Answer The depolymerization of PMMA rate constant given by [26] rate constant = 3.87 x 10 exp(—175 kJ/mole/RgT) gm/cm sec. 

Reported vapor pressures of methyl methacrylate at various temperatures and the coefficients for the vapor pressure equations... 

FIGURE 15.1.1.12.1 Logarithm of vapor pressure versus reciprocal temperature for methyl methacrylate. 

Bywater, S. (1952) Vapor pressures of methyl methacrylate and styrene. J. Polym. Sci. 9, 417. 

Monomers and resins were used as received from the manufacturers. N-Vinyl-pyrrolidone was chosen for its low vapor pressure (0.1 mbar at 24°C) and its relatively low toxicity. Methacrylamide was used as 15 wt % aqueous solution (maximum water solubility up to 20%) with the aim of partial wood impregnation. n-Butyl methacrylate was preferred to methyl methacrylate for giving a more flexible polymer with a lower glass-transition temperature, f g (20 °C instead of 105 °C for poly(methyl methacrylate) (PMMA)) (5) and much lower vapor pressure [2.7 mbar at 20 °C, compared to 38.7 mbar for methyl methacrylate (MMA)]. 

Monomers. Methyl methacrylate and methacrylic acid have well recognized toxicity characteristics as regards inhalation, ingestion and skin contact. Compositions containing large quantities of these materials have been rejected for use on certain production lines, e.g. automotive assembly. (Interestingly, the use of dimethacrylates, as in ref. (4), which have lower vapor pressure, may ease this situation, at the expense of... 

In thermal debinding, the binder is removed as a vapor by heating at ambient pressure in an oxidizing or nonoxidizing atmosphere or under a partial vacuum. The process is influenced by both chemical and physical factors. Chemically, the composition of the binder determines the decomposition temperature and the decomposition products. Physically, the removal of the binder is controlled by heat transfer into the body and mass transport of the decomposition products out of the body. In practice, binder systems consist of a mixture of at least two components that differ in volatility and chemical decomposition. The ceramic powder may alter the decomposition of the pure polymer. In view of the complexity of real systems, we first consider the basic features of thermal debinding for a simplified system consisting of a powder compact with a single binder, e.g., a thermoplastic polymer such as poly(methyl methacrylate) or polyethylene. Later,... 

Synonyms Methacrylic Acid, Butyl Ester Butyl Methacrylate Butyl 2-Methacrylate n-Butyl alpha-Methyl Acrylate Butyl 2-Methyl-2-Propenoate Chemical Formula CH,=C(CHi)COOCHiCH,CH2CH3 (ii) Observable Characteristics — Physical State (as normally shipped) Liquid Color Colorless Odor Moderate acrylate (iii) Physical and Chemical Properties — Physical State at 15 C and 1 atm. Liquid Molecular Weight 142.2 Boiling Point at 1 atm. 325, 163, 436 Freezing Point <32, <0, <213 Critical Temperature Not pertinent Critical Pressure Not pertinent Specific Gravity 0.8975 at 20 C Vapor (Gas) Density Not... 

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