A composite of 60% of lanthanum stearate and 40%（mass fraction） of stearic acid was prepared and its influence on the crystallization characteristics of isotatic polypropylene （iPP） was investigated. The results s...A composite of 60% of lanthanum stearate and 40%（mass fraction） of stearic acid was prepared and its influence on the crystallization characteristics of isotatic polypropylene （iPP） was investigated. The results showed that we had found a new kind of β-crystalline form nucleating agent. The composite might induced rather high proportion of β-modification. The relative content of β-phase estimated by WAXD and DSC was 30% and 51.8% in a PP containing 2.5%（mass fraction） of the composite respectively. The isothermal crystallization at 130 ℃ and melting behavior examined by DSC revealed that the composite accelerated the overall rate of crystallization remarkably. The half crystallization period t1/2 decreased from 11 8 min of pure PP to 7 5 min of PP containing 2.5% of the composite. However, the composite had no obvious influence on crystallization mode and the size of α-crystal unit cell.展开更多
文摘A composite of 60% of lanthanum stearate and 40%（mass fraction） of stearic acid was prepared and its influence on the crystallization characteristics of isotatic polypropylene （iPP） was investigated. The results showed that we had found a new kind of β-crystalline form nucleating agent. The composite might induced rather high proportion of β-modification. The relative content of β-phase estimated by WAXD and DSC was 30% and 51.8% in a PP containing 2.5%（mass fraction） of the composite respectively. The isothermal crystallization at 130 ℃ and melting behavior examined by DSC revealed that the composite accelerated the overall rate of crystallization remarkably. The half crystallization period t1/2 decreased from 11 8 min of pure PP to 7 5 min of PP containing 2.5% of the composite. However, the composite had no obvious influence on crystallization mode and the size of α-crystal unit cell.
