Poly (phosphate ester) s, PPE 1a-d, were synthesized from polycondensation of methyl phosphorodichloridate (MPDC) with various bisphenols such as 4,4’-biphenol 1a, 4,4’-dihydroxyphenylether 1b, bis(4-hydroxyphenyl)methane 1c, and 3,3’-dimethyl-4,4’-dihydroxybiphenyl 1d. PPE 2a-d with hexamethylene spacers were also obtained from polycondensation of MPDC with 4,4’-bis(6-hydroxyhexyloxy)biphenyl 2a, 4,4’-di(6-hydroxyhexyloxy) phenyl ether 2b, bis [4-(6-hydroxyhexyloxy)phenyl] methane 2c, and 3,3’-di-methyl 4,4’-di(6-hydroxyhexyloxy)biphenyl 2d. The degree of crystallinity of PPE 1a-1d without hexamethylene spacer was 3.3-17.6%, whereas PPE 2a and PPE 2b which exhibit mesomorphic behavior were 20.1 and 18.6%, respectively. PPE 2a and PPE 2b show the mesophase at 139.6-195.5-degrees-C and 42.4-66.3-degrees-C, respectively. PPE 2c and PPE 2d were obtained as rubbery. From pyrolysis of PPE in air the temperature corresponding to 5% weight loss was found to be 322-408-degrees-C and 284-291-degrees-C for PPE 1 and PPE 2, respectively. It was also found that PPE 2a was enzymatically degraded by phospholipase C.