Polyfmethyl methacrylate processing

J.P. Berry, Fracture processes in polymeric materials. I. The surface energy of polyfmethyl methacrylate), J. Polymer Sci., 50, 107-115, 1961. 

After hydrolysis by 2N methanol solution of H2SO4, the product was neutralized with KOH to pH=5 and methanol evaporated. The dry residue was expected to be poly(allilamine), polymethacrylic acid, and K2SO4. Indeed, after extraction with anhydrous methanol and acetone, poly(allilamine) was identified by NMR and IR spectrometries. After evaporation, solvent from the methanol part of the extract insoluble in chloroform part was obtained. After esterification by diazomethane the product was identified as polyfmethyl methacrylate) on the basis of IR and H-NMR spectroscopy. IR spectroscopy was applied in order to examine the copolymerization of multimethacrylate (p-cresyl-formaldehyde oligomers with methacrylic groups) with st3rrene. It was found that double bond peak at 1650 cm disappeared during the process and it was absent in the product of polymerization. Polymerization and... 

Methacrylic acid has been used for the synthesis of polyfmethyl methacrylate). It has been synthesized industrially via a reaction of acetone with hydrogen cyanide (12, 17, 330, 331). However, the process produces ammonium bisulfate and uses the toxic hydrogen cyanide. Recently, an alternative, a two-step oxidation of isobutylene, has been developed. The first step is the oxidation of isobutylene to methacrolein, and the second is the oxidation of methacrolein to methacrylic acid ... 

Figure 13.7 Block flow diagram of current polyfmethyl methacrylate) (PMMA) monomer recycling process. MIB, Methyl isobutyrate MA, methyl acrylate MMA dimer, 1,4-cyclohexane dicarboxylic acid dimethyl ester [87]. Modified from Kikuchi Y, Hirao M, Sugiyama H, Papadokonstantakis S, Hungerbuehler K, Ookubo T, et al. Design of recycling system for poly(methyl methacrylate) (PMMA). Part 2 process hazards and material flow analysis. Int J Life Cycle Assess 20i4 i9(2) 307—19.

Several other types of hydrocarboxylations and hydroesterifications have been conducted with rates and selectivity that are appropriate for the synthesis of fine chemicals and commodity chemicals. One target for hydroesterification has been methyl methacrylate, the monomer of polyfmethyl methacrylate), which is the polymer often called "acrylic". It is estimated that 2.1 million metric tons of methyl methacrylate was produced in 2005. Much of this material is produced from acetone cyanohydrin, but two alternative routes could involve catalytic carbonylation. The first route would involve the hydroesterification of methylacetylene, and this chemistry relates to the original route to methyl methacrylate by carbonylation of methylacetylene using nickel carbonyl as catalyst. The second route involves the sequence of ethylene hydoesterification, aldol addition of the resulting ester to formaldehyde, and dehydration. This sequence comprises Lucite s new "Alpha" process and is shown in Equation 17.33. The route to methyl methacrylate by hydrocarboxylation of ethylene produces water as the only byproduct. 

Methyl methacrylate (MMA) is by far the most important methacrylic ester monomer, accounting for 90% of the volume of methacrylic ester monomers. Polyfmethyl methacrylate) (PMMA) was first synthesized in 1928 in various laboratories, and was first brought to market in 1933 by Rohm Haas Co. under the trademark Plexiglas. ICI then reformed Rohm s method and commercialized MMA in 1937 by the acetone cyanohydrine (ACH) process,[l] which is still the most widely adopted technique even today. The world production capacity of PMMA has almost doubled in the past fifteen years, and overall global PMMA production capacity accounts for six hundred and fifty thousand tons per year. [3] It is predicted that starting from 2010, the demand for PMMA will rise by 3-5% annually and the demand of MMA is expected to steadily grow in the future.[3]... 

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