Bar soap Cracking study by Differential Scanning Calorimetry

Tuesday, April 30, 2024

5:00 PM – 6:00 PM EDT

Presenting Author(s)

Erick Ansony Cardenas (he/him/his)

Sr. Scientist
Colgate Palmolive
Ciudad DE Mexico, Mexico

Co-Author(s)

Ivan Romero (he/him/his)

Sr. Scientist
Colgate Palmolive
Ciudad de Mexico, Distrito Federal, Mexico

Abstract: Using DSC to characterize bar soap (BS) crystalline structure, it investigated different polymorphic phases of fatty acid sodium salts from commercial BS. The crystalline soaps phases are related to different performance attributes such as lather, hardness and cracking. Cracking’s fundamental cause is the stress applied to the structure of the BS when it's weak. When in contact with water, BS swells, then dries and shrinks. Depending on how weak the crystalline structure is, BS will crack. Crystalline BS structure is determined by formula and processing. The presence of C12, C18 and C16 fatty acids, which come from fat & oil sources are crucial in BS composition. In this study thermal profiles of BS with and without cracking were determined. Results showed that thermal transitions occurring at 100°C and 160°C determine the cracking severity for BS with high stearic acid palmitic acid content. Additionally, electrolyte content or temperature condition/mechanical work during manufacture play an important role in the crystal soap transitions development to avoid cracking, results showed different phase transitions arrangement depending on cooling rate crystallization conditions (°C/min) and electrolyte concentrations.