Retarding crystal transitions of polybutene-1 in blends

Abstract

In this study, copolymers of 1-butene with allyltrimethylsilane (TMAS) were synthesized via rac-ethylenebis(indenyl)zirconium chloride (rac-Et(Ind)₂ZrCl₂)/methylaluminoxane (MAO) catalyst. Combining ¹H-NMR and Fourier transform infrared (FT-IR) spectroscopies, the microstructure of the copolymer was verified and the insertion rate of TMAS was calculated. Herein, we demonstrate that the isotacticity and thermal decomposition temperature of the copolymers decreased with the contents of allyltrimethylsilane in the copolymers. After blending the resultant copolymers with high isotactic poly(1-butene) powder (HI-PB), it was found that the 1-butene-allyltrimethylsilane copolymer (PB-TMAS) reduced the crystallization temperature, inhibited the formation of form I in the amorphous region at the initial stage of crystal transformation, and slowed down the crystalline transformation from form II to form I, but did not affect the time of the initial reduction of form II.