สำนักราชบัณฑิตยสภา

The Journal of the Royal Institute of Thailand √–∫∫∑ÿ ππ‘ ¬¡¿“¬„µâ √–∫Õ∫ª√–™“∏‘ ª‰µ¬·∫∫‰∑¬ Properties of Industrial Thai Silks Reeled by Hand and by Machine Vol. 32 No. 1 Jan.-Mar. 2007 134 Properties of Industrial Thai Silks Reeled by Hand and by Machine Usa Sangwatanaroj 1 Piyawan Puicharoen 1 Suda Kiatkamjornwong 2 Associate Fellow of the Academy of Sciences, The Royal Institute, Thailand Abstract Three mulberry silk filaments from the local producers and one imported silk filament were analyzed for various properties. The properties of the silk filaments reeled by hand and by machine were compared. The properties assessed were whiteness and yellowness, fineness or denier, degumming weight loss, moisture content, relative density, birefringence, crystallinity, chemical composition, softening point, burning behavior, tenacity, resistance to sunlight, dye fixation, and resistance to acid, alkaline and bleaching conditions, according to the standard test methods. It was found that the hand reeled silks showed the lower values in whiteness, birefringence, crystallinity and softening point than those of the machine reeled silks. On the other hand, the hand reeled silks showed a higher denier and dye fixation. The local silks were found to have the higher values in denier, degumming weight loss, relative density, crystallinity, dye fixation, and resistance to alkali and bleaching agent than the imported Chinese silk. Key words : Thai silk, hand reeling, machine reeling, properties Introduction There are various kinds of silk depending on source such as Thai silk, Indian silk, and Chinese silk. Thai silk filaments differ from those of other countries in many ways. They are usually soft but have a relatively coarse texture with uneven, slightly knotty threads (a unique property not found in other silks). Silk in Thai- land can be classified into three types based on the silk worm spe- cies namely Thai silk worms, a mixed hybrid of Thai and foreign silk worms and mixed hybrid of foreign silk worms. These silk worms produce varying qualities and properties of silk filaments. In addition, the properties of silk filaments in Thailand have not really been investigated and characterized. Asakura et al. 1 studied the structure of Bombyx mori silk fibroin using the solid state 13 C- NMR technique. As expected, the NMR spectra showed very sharp 13 C-NMR signals of the silk fibroin. These results indicated 1 Department of Materials Science, Faculty of Science, Chulalongkorn University, Phyathai Road, Patumwan, Bangkok 10330, Thailand. E-mail: usa@sc.chula.ac.th 2 Department of Imaging and Printing Technology, Faculty of Science, Chulalongkorn University, Phyathai Road, Patumwan, Bangkok 10330, Thailand. E-mail: ksuda@chula.ac.th