Patent ID: 7696299

Claim:
A method of making a rapidly crystallizable amorphous polyethylene naphthalate (PEN) polymer, the method comprising the steps of: (a) transesterifying dimethyl 2,6-naphthalene dicarboxylate (NDC) in the presence of (i) monoethylene glycol (MEG); (ii) at least one transesterification catalyst; and (iii) at least one nucleating agent, wherein about 80% of the transesterifying step is carried out at about 1050 mbar followed by about 20% of the transesterifying step being carried out at about 500 mbar, to form a prepolymer; and (b) polymerizing the prepolymer at about 250° C. to about 305° C. in the presence of a polymerization catalyst and at least one thermal stabilizer.