Thermoanalytical Ranking of Catalysts for Use with Polycarboxylic Acids as Durable Press Reactants 1

Abstract

Thermoanalytical (TA) techniques were used to analyze several polycarboxylic acids (PCA) in the presence of each of three inorganic salts of phosphorus-containing acids used as catalysts—disodium phosphate, monosodium phosphate, and sodium hypo-phosphite. The influence of catalyst was measurable in differential scanning calorimetric and thermogravimetric analyses. Previously, TA data gathered on PCAs alone indicated that the acids that performed best in fabric trials produced large residues, low rates of weight loss/minute, and high total heats of reaction in J/g. Adding a catalyst to an acid increased residues and decreased rates even further. Total heat values decreased slightly in the presence of the catalyst. A mathematical transformation incorporating the three TA parameters into a single predictor factor was used to rank catalysts and predict which catalyst was best for each of four acids of interest to textile chemists. When this TA factor was compared with another factor derived from fabric durable press and strength data, the rankings agreed.