| abstract |
The present invention relates to a preparing method of high purity benzyloxypolyethyleneglycol (Benzyl PEG) and its derivatives. More precisely, according to this method, the commercial, general low purity benzyloxypolyethyleneglycol (Benzyl PEG) is reacted to produce benzyloxypolyethyleneglycol-phthalate (Benzyl PEG-phthalate), the high purity intermediate, and then high purity benzyloxypolyethyleneglycol (Benzyl PEG) having the molecular weight of 350 ~ 100,000, the polydispersity (PD) of up to 1.05 and the purity of at least 99% is prepared from the intermediate. |