A) SEM photographs of fracture surface of the composites without and with
different diisocyanates ((a) untreated, (b) HDI treated, (c) IPDI treated and (d) MDI
treated); (B) the mechanism of enhancement in the interface of ramie and PLA by
using the diisocyanates as compatibilizer. (For interpretation of the references to
colour in this figure legend, the reader is referred to the web version of this article.)