caa a22 4500 465750885 CHVBK 20180323111833.0 cr unu---uuuuu 170327e19900901xx s 000 0 eng 10.1007/BF02322814 doi (NATIONALLICENCE)springer-10.1007/BF02322814 Issa Sameh Civil Engineering Department, Kuwait University, P.O. Box 5969, 13060, Safat, Kuwait aut Highlights of the optical anisotropy of unstressed transparent polymeric plates [Elektronische Daten] [Sameh Issa] The photoelastic effect is cumulative, therefore the presence of material birefringence in unstressed transparent polymers might lead to erroneous photoelastic analyses. This presence is more influential in the scattered-light photoelasticity. Direct-transmission polariscopes are not suitable for detecting all material birefringence in normally illuminated plates because the birefringence in question coincides with the wave normal of the propagating light. The present paper describes phenomenologically the presence of the material birefringence in an arbitrarily selected group of unstressed cross-linked polymers and presents means of their determination. The material-birefringence information obtained can be used as a means of taking proper precautions for conducting faultless scattered-light photoelastic analyses. Octagonally shaped plates were machined to permit data acquisition using four different light-propagation directions. The orientation and diffusion of molecular chains appear to be the major source of the material birefringence observed. Society for Experimental Mechanics, Inc., 1990 Experimental Mechanics Kluwer Academic Publishers 30/3(1990-09-01), 224-229 0014-4851 30:3<224 1990 30 11340 https://doi.org/10.1007/BF02322814 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02322814 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Issa Sameh Civil Engineering Department, Kuwait University, P.O. Box 5969, 13060, Safat, Kuwait aut NATIONALLICENCE 773 0- Experimental Mechanics Kluwer Academic Publishers 30/3(1990-09-01), 224-229 0014-4851 30:3<224 1990 30 11340 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer