탄성 Braid의 특성에 관한 연구(II) ―탄성 Braid의 제조조건에 의한 특성변화―

A Study on the Characteristics of Elastic Braid(II) ―Effect of Manufacturing Condition on the Characteristics of Elastic Braid―

Dependence of physical properties on manufacturing conditions of cotton elastic braid made of core latex rubber thread were studied experimentally. The results as follows; 1) Breaking strength had little effect on braiding angle($\theta$a), and elongation was proportional to tan $\theta$a. 2) Relation between limiting elongation and strain ratio of core latex rubber thread showed a linear function of which slope coresponds to a draft ratio in manufacturing process(Da). 3) Tensile stress was depended on $\theta$a. 4) Stress relaxation behaviour of the elastic braid satisfied the stress relaxation equation of polymerec elastomers as shown below. ln ft=lnfto-K ln n Where K values, rate of stress relaxation of the elastic braid, can be expresses as; K=(0.1101-0.7763u)k When considered the strain ratio of rubber thread, from this equation, calculation of the stress relaxation rate(k) of rubber thread enables the estimation of tensile stress at any time.