Patent ID: 7619053

Claim:
A method of forming a non-reactive monomer mixture suitable for use in a melt transesterification reaction to form polycarbonate, the method comprising the steps of: (i) providing a diaryl carbonate; (ii) selecting a first monomer compound having a melting point that is greater than the melting point of the diaryl carbonate, (iii) performing a monomer conditioning step selected from the group consisting of: (a) testing the first monomer compound for the presence of alkali metal prior to forming the non-reactive monomer mixture, and if said alkali metal is present, performing a step selected from the group consisting of: (I) treating the first monomer compound to reduce the level of said alkali metal to an amount of less than 600 ppb, (II) adding an acid stabilizer to the first monomer compound, and (III) a combination of steps (I) and (II), and (b) treating the first monomer compound with a step selected from the group of: (I) treating the first monomer compound to reduce the level of said alkali metal to an amount of less than 600 ppb, (II) adding an acid stabilizer to the first monomer compound, and (III) a combination of steps (I) and (II), (iv) adjusting the temperature of the diaryl carbonate to a first temperature that is: greater than the melting point of the diaryl carbonate; and below the melting point of the first monomer compound; (v) adding the first monomer compound as a solid to the diaryl carbonate, wherein the first temperature is selected such that the first monomer compound added to the diaryl carbonate disperses in the diaryl carbonate to produce a first monomer mixture, and (vi) selecting a second monomer compound, wherein the first monomer compound requires a higher temperature to disperse in the diaryl carbonate than the second monomer compound, lowering the temperature of the first monomer mixture to a second temperature sufficiently high to maintain the first monomer compound in solution and to permit dispersion of the second monomer compound, said second temperature being above the melting point of the second monomer compound, and adding the second monomer compound to the non-reactive monomer mixture at the second temperature, wherein the second temperature is selected such that the second monomer compound added to the non-reactive monomer mixture disperses in the non-reactive monomer mixture.