| 摘要： | Poly(ethylene-octene) (POE), maleic anhydride
grafted poly(ethylene-octene) (mPOE), and a mixture
of POE and mPOE were added to poly(butylene terephthalate)
(PBT) to prepare PBT/POE, PBT/mPOE, and PBT/
mPOE/POE blends by a twin-screw extruder. Observation
by scanning electron microscopy revealed improved compatibility
between PBT and POE in the presence of maleic
anhydride groups. The melting behavior and isothermal
crystallization kinetics of the blends were studied by wideangle
X-ray diffraction and differential scanning calorimeter;
the kinetics data was delineated by kinetic models.
The addition of POE or mPOE did not affect the melting
behavior of PBT in samples quenched in water after blending
in an extrude. Subsequent DSC scans of isothermally
crystallized PBT and PBT blends exhibited two melting
endotherms (TmI and TmII). TmI was the fusion of the crystals
grown by normal primary crystallization and TmII was
the melting peak of the most perfect crystals after reorganization.
The dispersed second phase hindered the crystallization;
on the other hand, the well dispersed phases with
smaller size enhanced crystallization because of higher
nucleation density. |
