Effects of added ammonium laurate soap on natural rubber latex

Abstract

Low quality natural rubber latex, matured with different levels of well known long chain fatty acid salt showed variations in properties. Mechanical stability time.foaming height and viscosity were significantly altered by the added ammonium laurate soap level. Potassium hydroxide number and conductivity showed existence of a similar effect apparently up to a certain level of the added soap. Soap levels above 0.5 X 1()'4 moles per 100 g of latex enhance the mechanical stability time as well as foaming height. Magnitude of the effect depends upon the amount of the added soap. Initial viscosity was decreased by soap addition but a progressive increase and corresponding decrease was observed thereafter. Both potassium hydroxide number and conductivity increased with increasing levels of soap and attained a constant value after 5 X 1()'4 moles of soap per 100 g latex. Soap levels between 4.2 X 1()'4 and 5 X 1()'4 moles per 100 g latex were the critical levels with rapid changes in properties. There was no effect of fatty acid soap on MST on matured latex.