Blends of poly(butylene terephthalate) (PBT) with thermotropic liquid crystalline polymer (LCP) concentration down to 0.2 wt.% were prepared to investigate the effects of LCP component on the crystallization behavior of PBT. The crystal structure of PBT in the blends was not deteriorated by the presence of LCP. The regularity of PBT crystals in the blends with lower LCP content appeared to be more perfect, compared with that of pure PBT sample and of blends with high LCP content. The experimental results revealed that the LCP component may affect, to a great extent, the crystallization process of the blends due to the inhomogeneous nature of the LCP used. The crystallization process of PBT in the blends was very sensitive to the LCP content and its microstructures existing in the melt before the start of crystallization, with the nucleation effect of the LCP component in its crystalline state being more efficient than that in its nematic state. The favorable content at which the LCP microdomains show ''the most efficient nucleation’’ is more likely to occur at lower LCP content for these systems. Based on the fact that the addition of the LCP component leads to higher crystallization temperature, crystallinity and degree of perfection of the crystallites formed, it is proposed that the effects of heterogeneous nucleation dominate in the crystallization process of the blends with lower LCP concentration.
Посилання на статтю:
Crystallization of poly(butylene terephthalate) blends containing liquid crystalline polymer component / Huiming Yan, Jiarui Xu, Kancheng Mai, Hanmin Zeng // Polymer. – 1999. – N 40. – P. 4865–4875.
