1,3,5-Benzenetrisamide based nucleating agents for poly(vinylidene fluoride)

This paper presents 1,3,5-benzenetrisamides as colorless α-nucleating agents for poly(vinylidene fluoride). In order to screen a large variety of 1,3,5-benzenetrisamide derivatives with respect to their nucleating potential an efficient and reliable test based on polarized light microscopy was established. For selected promising compounds the concentration dependence of the PVDF crystallization temperature, the dissolution behavior of the additive in the polymer melt, and the crystallization of the additive from the polymer melt was investigated in a concentration range between 1 wt% (10,000 ppm) and 70 ppm. It was found, that only two of the investigated compounds were able to raise the crystallization temperature about 8 °C at a concentration of 140 ppm and 580 ppm, respectively. These trisamides have the advantage being soluble in the polymer melt, not featuring absorption of visible light and therefore allowing the preparation of uniform and colorless PVDF products.