The maximum take‐up velocity as a spinnability criterion and its dependence on the composition of coagulation bath, illustrated by an example of sodium alginate

Abstract

We present the results of a study of sodium alginate solutions spinnability in a coagulation bath containing CaCI, and HCl. The spinnability is estimated by means of the measurement of the maximum take-up velocity (MTUV) of the fiber at the time of breaking. We have demonstrated that MTUV represents a function of parameters associated with the peculiar features of coagulation. A simplified relation is suggested which allows to consider MTUV as spinnability criterion.In preparing ,,dope" solutions or fiber spinning for manufacturing artificial meat products one of the fundamental question is the criterion of spinnability.In order to estimate spinnability, the ,,drop method" [I] and the ,,rod method" [z] have been suggested. Their short-comings arise from the fact that they ignore the processes that occur in the coagulation tank, from the low values of the longitudinal velocity gradient as compared to those specified by technological conditions, and also from the non-stationary nature of the flow [3]. Therefore, at present they are rarely applied.Nowadays two other methods are more frequently used, the first of them consists in determining the maximum take-up velocity of fiber (MTUV) under actual conditions of its formation [4]. Its advantages follow from its being simple and efficient. This method, however, has not sufficiently well been justified theoretically, so that it is difficult to imagine the nature of dependence of the finished fiber performance characteristics on the magnitude of MTUV.The second method is based on production and processing of the spinning solution as dependent on the properties of the finished fiber [5,6]. It is, however, less acceptable in the laboratory research since its efficiency is relatively low.The present report discusses the results of the analysis of the coagulation bath composition (the acid solution of calcium chloride) affecting spinnability of sodium alginate solutions, based on determination of MTUV. The above object of research has been chosen in view of the fact that the sodium alginate solutions are characterized by appropriate spinning qualities. Experimental MaterialsSodium alginate (British Drug Houses Chemicals Ltd, England) : the content of the main component is not below 95%.[v] = 10.5 deciliterlg at 25 "C in a aqueous solution with the ion concentration of 0.2 mole/l. the molecular mass 1.5 f 0.2 . 10) glmole. The specimen was not purified additionally.