Crystallization behavior of poly(lactic acid) with a self-assembly aryl amide nucleating agent probed by real-time infrared spectroscopy and X-ray diffraction

The effect of a self-assembly nucleating agent, N,N',N-tricyclohexy1-1,3,5-benzenetricarboxylamide (BTCA), on the crystallization behavior of poly(lactic acid) (PLA) was probed by time-resolved Fourier transform infrared spectroscopy (FTIR) and wide angle X-ray diffraction (WAXD). The vibrational changes associated with inter and intra-chain interactions during crystallization were monitored. In the initial period of crystallization, the order of intensity changes is as follows: 1458 cm(-1) > 1210 cm(-1) 921 cm(-1), 1458 cm(-1) similar to 1210 cm(-1) > 921 cm(-1), and 1458 cm(-1) similar to 1210 cm(-1) similar to 921 cm(-1) for neat PLA, PLAs containing 0.1 wt% and 0.3 wt% BTCA, respectively. This indicates that BTCA can accelerate both the formation of skeletal conformational-ordered structure and, especially, the 10(3) helix one. The incorporation of BTCA changes the crystallization mechanism but has no impact on the crystal form of PLA.