Effects of high energy electrons on physical and tensile properties of non-mulberry silk fibers     

Sangappa  B. Lakshmeesha Rao  S. Asha  S. Ganesh  R. Somashekar  Timma Reddy 《Fibers and Polymers》2013,14(6):1032-1039

Tassar silk fiber (Antheraea mylitta) was irradiated with the available maximum dose range upto 100 kGy using 8 MeV electron beam at room temperature. Irradiation effect in these fibers is quantified in terms of the changes in microstructural parameters studied using wide-angle X-ray scattering data (WAXS). The crystal imperfection parameters such as crystallite size (〈N〉), lattice strain (g in %), and surface weighted crystallite size (D_s in Å) have been determined by line profile analysis (LPA) using Fourier method of Warren. For this purpose, exponential, lognormal, and Reinhold functions for column length distribution have been used for the determination of these parameters. These parameters were compared with tensile properties of the fibers. The increasing trend of crystallite size values (〈N〉 as well as D_s in Å) and tenacity (gf/den) with increasing dosage of radiation clearly indicates the cross linking polymer network in fiber. Comparison of SEM photographs also confirms the X-ray results.  相似文献   

Quantification of degradation and surface morphology of NB7 silk fibers irradiated by 8 MeV electron beam using XRD and SEM techniques     

Sangappa  S. Asha  R. Somashekar  Ganesh Sanjeev 《Fibers and Polymers》2012,13(2):224-230

NB7 silk fiber (Bombyx mori) was irradiated with the maximum dose range of 100 kGy using 8 MeV electron beam at room temperature. Irradiation effect in these fibers is quantified in terms of the changes in microstructural parameters employing X-ray diffraction line profile analysis technique. For this purpose we have used three asymmetric distribution functions for column lengths in a crystal. The decreasing trend of crystallite size values (〈N〉 as well as D _s ) and crystallinity with increasing dosage of radiation clearly indicates the degradation of fiber. Of the several factors responsible for such a behavior, we presume that the chain scission of polymer network is a significant one over others and it is well pronounced here, leading to low molecular weight of the samples. This degradation is attributed to many changes in tensile properties of the polymer. Comparison of SEM photographs also confirms the X-ray results.  相似文献