PET-clay hybrid is a nano composite of PET and uniformly dispersed silicate layers of montmorillonite.Cation exchange capacity of the montmorillonite used in our laboratory is 90 meq./100g.The montmorillonite is a sheet-like particles which are composed of monolayer of 10nm long

10nm wide and 1nm thick.Montmorillonite was dispersed in water or EG

then a kind of nitrogen-onium ion was added to exchange cations between layers of the montmorillonite.Because interlayers were intercalated by onium ion

the interlayer spaces were increased

subsequently the layers of the montmorillonite were delaminated and uniformly dispersed in the solvent.The above treated montmorillonite was mixed with PET oligomer.The mixtures were reacted for 3～4 h at 260 to 280℃

then the PET-clay hybrids were yielded.It is revealed by electron microscopy that the montmorillonite layers are uniformly dispersed at 30～50 nm layer thick in the PET matrix.Crystallization rate of PET-clay is about 4～5 times as quick as that of PET.X-ray patterns of PET-clay hybrids which was quenched at 160℃/min were abtained by WAXD.Crystallinities were calculated by peak resolution method.It is about 53% for quenched PET-clay and much higher than that of pure PET.Neither quenching nor isothermal samples show perfect spherulite structure.It is too small for the size of the spherulite to observe as typical pattern of PET spherulite using polar microscopy and SALS.The montmorillonite layers could act as nucleating agents during crystallization thus increasing crystallization rate

so that molding temperature could be decreased to 60～80℃ during the injection molding.Mechanical and thermal properties of the hybrids were superior to those of PET.The PET-clay hybrids have excellent spinnability.The tensile modulus of the fibers spum by the hybrids is 160% as high as the one of PET fibers.