115 [degrees] C); and feed the azeotropic
agent continuously to the top of the column instead of to the pot.
XP10 is new non-flammable, azeotropic
refrigerant designed to replace R-134a in supermarket systems which have large refrigerants charge sizes and therefore restrictions for using flammable refrigerants.
Wagner, "Application of the Wilson- Equation to Azeotropic
Mixtures," Fluid Phase Equilib.
Sample preparation procedures included solid phase extraction, azeotropic
distillation, and pentafluoro (methyl) benzylbromide (PFBBR) derivitization.
Zinc octeat (0.08% (w/w) based on epoxy resin) was used as catalyst and xylene (5% (w/w) based on reaction mixture) was used as azeotropic
The resulting mixture was degassed with nitrogen at the ambient temperature, and heated to reflux at 135-140[degrees]C for 3 h to remove all water from the reaction by azeotropic
2 for a constant desired overall monomer conversion ([x.sub.md]) of 0.94 and the styrene mole fraction in the copolymer ([St.sub.cd]) of 0.597 (this value is near the azeotropic
composition  of SAN under nonbulk polymerizations, and is useful to avoid composition drift).
Both the liquids form azeotropic
mixtures at lower compositions of water that are difficult to separate by conventional distillation.
The reactivity ratios for the AN:AA system where studied by several authors for different polymerization conditions [52-57], It is known that the feed fractions of monomers are equal to the copolymer fractions only in the case of azeotropic
copolymerization and that the influence of the reactivity ratios on the final copolymer composition is more important in the cases of small conversion (3-4%), and less important for the cases of high conversion (70-80%), which is the case of the current work, with an average conversion of 74%.
The separation trend of aqueous azeotropic
solution comprising 99.5 wt% n-butanol/0.5 wt% water at different temperatures (28, 45, 55, 66[degrees]C) through M4 and M10 was studied and the results are displayed in Fig.
The resulting mixture was degassed with nitrogen at the ambient temperature, stirred, and heated to reflux at 135-145[degrees]C for 3 h to remove all water by azeotropic
A-Methyl-2-pyroridone (NMP, Junsei Chemical Co.), a polymerization solvent, p-xylene (Junsei Chemical Co.), an azeotropic
agent, and tetrahydrofuran (THF, Junsei Chemical Co.) were dehydrated with well-dried 4A molecular sieves.