Cold crystallization behavior of poly(lactic acid) in its blend with acrylic rubber; the effect of acrylic rubber content

Understanding the crystallization process of polymer blends is of great importance for designing their process conditions, especially when the crystallization occurs during heating, so-called cold crystallization. In this paper, the cold crystallization behavior of poly(lactic acid) (PLA) in its blends with acrylic rubber (ACM) was studied as a function of ACM content, using various techniques including differential scanning calorimetry, polarized optical microscopy and rheological methods. It was found that the addition of 10 wt% - 20wt% ACM to the PLA accelerated its cold crystallization. However, on using a greater amount of ACM up to 30%, the rate of crystallization was not further increased. In the ACM-rich blends, the crystallizable PLA domains were distributed inside the amorphous ACM matrix and consequently confined crystallization occurred. The observed effects are discussed in terms of the interplay between chain mobility enhancement and the influence of phase boundaries. (C) 2017 Society of Chemical Industry