Mechanical and Thermal Degradation Properties of Silk from African Wild Silkmoths
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Date
2012Author
Onyari, Mmari
Teshome, Addis
K, Raina
Kaburu, Jacques
Vollrath, Fritz
Type
ArticleLanguage
enMetadata
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Variations among silk of four African wild silkmoths, Argema mimosae, Anaphe panda, Gonometa postica, and Epiphora
bauhiniae, was studied regarding their mechanical properties and thermal degradation behaviors. Cocoon shells and individual
degummed fibers were examined using tensile testing, thermogravimetric analysis, and scanning electron microscope (SEM). A. mim-
osae and G. postica cocoon shells had marginally higher initial moduli and strains at maximum stress. The stress–strain curves of Bob-
myx mori and A. panda degummed fibers lacked clear yielding points. G. postica fibers had the highest breaking energy (76.4 J/cm3)
and breaking strain (41.3%). The ultimate tensile strength was the highest for B. mori (427 MPa). Fiber pull-out and detachment was
predominant in fracture surfaces of both the cocoon shells and the fibers. Wild cocoon shells and degummed fibers had higher tem-
perature for dehydration loss than B. mori. A. mimosae fibers (11.9%) and G. postica cocoon shells (13.3 %) had the highest weight
loss due to dehydration. E. bauhinae cocoon shells and B. mori fibers had the highest total weight losses of 97.2 and 93.4%, respec-
tively. The African silks exhibited variations in their mechanical and thermal degradation properties related to their physical and
chemical structure and composition.
URI
http://profiles.uonbi.ac.ke/jonyari/publications/mechanical-and-thermal-degradation-properties-silk-african-wild-silkmothshttp://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/26760
Citation
Mechanical and Thermal Degradation Properties of Silk from African Wild Silkmoths, Addis Teshome, Onyari John M., Raina Suresh K., Jacques M. Kabaru, and Fritz Vollrath, Suresh K. Raina , J. APPL. POLYM. SCI, Issue DOI: 10.1002/APP.37873, p.5-15, (2012) copy at http://profiles.uonbi.ac.ke/jonyari/publications/mechanical-and-thermal-degradation-properties-silk-african-wild-silkmothsPublisher
Department of Chemistry