Thermal characteristics and phase structure of thermostable polyimide/polyurethane film materials - O. P. Grigoreva; A. M. Fajnlejb; O. N. Starostenko; T. A. Shantalij; K. G. Gusakova; V. V. Davidenko; J. M. Saiter; B. Youssef (Polymer journal, 2015)