A new nematic liquid crystalline copolysiloxane (LCP-H4) was prepared by graft polymerization

and a series of PP blends containing different mass fraction of LCP-H4 with propyloxy spacers were obtained by blending PP and LCP-H4 at a proper process program.The crystallization structure

morphology and thermal properties of PP with LCP-H4 as a nucleator were characterized with wide angle X-ray diffraction (WAXD)

polarizing optical microscopy (POM) and differential scanning calorimetry (DSC).The experimental results showed that LCP-H4 with mesomorphism in the PP could supply many crystal nucleuses and active spots

play a role in the heterogeneous nucleation effect

efficiently enhance the crystallization velocity

temperature and degree of crystallinity

moreover

the spherulites became smaller and more homogeneous.The nucleated PP showed different crystallization structure

morphology

and thermodynamics and kinetics.β-phase in the PP was induced

the maximal relative content of β-form (Kβ) was 54% when the mass fraction of LCP-H4 was 0.9%

and the crystalline temperature and time were 128℃ and 1 h

respectively.In addition

the birefringence of β spherulites is stronger than that of α spherulites

this difference is related to their particular growth way and lamellar morphology.The trigonal β spherulite with the sheaflike grain growth is bright and colorful compared with the black and white monoclinic α one with the cross-hatched radial grain growth.Moreover

the molecular arrangement of β crystal is looser than that of α crystal. The melting point of α- and β-crystal was about 153oC and 166oC

respectively.