6—THE EFFECT OF ALKALINE AND ACID SWELLING AGENTS ON THE MECHANICAL PROPERTIES OF COTTON FIBRES

Abstract

A study of the changes in mechanical properties of cotton brought about by sodium hydroxide, an iron tartrate complex in caustic soda (EWNN), cuprammonium hydroxide, and sulphuric, phosphoric, nitric, and perchloric acids has been made. Instead of choosing the normal mercerizing conditions with sodium hydroxide, different temperatures of treatment and of washing were studied to see what effect the condition had on the subsequent mechanical properties of the fibres. The variable studied with the other reagents was that of concentration, so that a distinction between interfibrillar and intrafibrillar swelling could be made. The main effect of swelling is to alter the extensibility of the fibre, and this has been analysed at different stages of loading up to break.

KEY WORDS (SPECIFIC TERMS):

• BREAKING STRENGTH
• STRAIN
• STRESS–STRAIN CURVES
• TENACITY
• INITIAL MODULUS
• FINAL MODULUS
• SECANT MODULUS
• INTERFIBRILLAR SWELLING
• INTRAFIBRILLAR SWELLING
• FIBRE LENGTH
• X-RAY ANGLE
• TEMPERATURE
• CONCENTRATION
• SCOURING
• COTTON
• FIBRES
• SODIUM HYDROXIDE
• FERRIC TARTRATE
• CUPRAMMONIUM HYDROXIDE
• SULPHURIC ACID
• NITRIC ACID
• PHOSPHORIC ACID
• PERCHLORIC ACID
• COMPUTERS

KEY WORDS (BROADER TERMS):

• MECHANICAL PROPERTIES
• STRESS–STRAIN PROPERTIES
• SWELLING
• FIBRE PROPERTIES
• SWELLING AGENTS
• ACIDS
• ALKALIS