Two calixarene derivatives（2a

2b） have been synthesized and used as macro-initiators to prepare star-shaped poly（ε-caprolactone）s（SPCLs） via controlled ring-opening polymerization of ε-caprolactone in the presence of yttrium tris（2

6-di-tert-butyl-4-methylphenolate） [Y（DBMP）

3

].The molecular weight of SPCLs was characterized by end group 1H-NMR analyses and size-exclusion chromatography（SEC）.The results indicated that SPCLs based on calix[4]

arene derivative（2a） are well-defined four-arm star polymers with narrow molecular weight distributions in a given molecular weight range

while SPCLs based on calix[6]arene derivative（2b） are star polymers not so defined.Differential scanning calorimetry（DSC） analyses suggested that the maximal melting point

the crystallization temperature

and the degree of crystallinity of SPCLs increase with the increasing of the molecular weight

and are lower than those of the liner poly（ε-caprolactone）（LPCL） counterpart.Furthermore

polarized optical microscopy（POM） indicated that SPCL exhibits irregular spherulites with poor morphology and apparently slower crystallization rate

whereas LPCL shows fast crystallization rate and good spherulitic morphology.