2) M. Kitagawa and T.Tuzuku, “Yield process of amorphous polymers PC and PVC”, ibd., Vol.52, pp.288-293 (2003).
3) M. Kitagawa, S. Ishida, K. Shibagaki and Y. Yamada, “Yield process of amorphous polymers with different heat treatments”, ibid. Vol.53, pp.327-332 (2004).
5) V. K. Stokes and H. F. Nied, “Solid phase sheet forming of thermoplastics-Part I : Mechanical behavior of thermoplastics to yield”, J. Eng. Mater. & Tech., Trans. ASME, Vol.108, pp.107-112 (1986).