In this research, methods for dissociation of leather fibres from scrap leather pieces of shoe manufacturing are studied. The types of scrap used are grain and corium cow leathers which are materials for common shoe making in Vietnam. Dissociation techniques used include: (1) dry crushing by mechanical methods using a hammer mill and (2) chemical pretreatment - assisted wet milling using NaOH and H2SO4 at various concentrations and retention time. Experimental results showed that both types are able to dissociate into fiber form materials by the wet and dry grinding methods. Wet grinding method using the pretreatment in H2SO4 is capable of forming fibers with less than 100 micron in diameter and up to several centimeters in length. Meanwhile, pretreatment with NaOH is only suitabe with curium leather and should only be used in low concentrations and short processing time. Grinding directly by hammer mill is fast and helped obtained fibres with small diameter (less than 0,1mm) but the length is shorter than those obtained from the H2SO4 method. These results are important for choosing the suitable crushing method in order to transform scrap leather into fiber form to be used for recycle materials production.
