Synthesis and Characterization of Modified Polysaccharides and their application in Fabric and Home Care

The composition of modern laundry products has dramatically changed throughout the last 20 years as a result of companies trying to meet the changing washing habits and demands of consumers [1]. Although surfactants still represent the main core of a laundry formulation, many other ingredients have been constantly introduced, thus enabling the fine control of the cleaning performances [1]. Besides builders, bleaching agents, enzymes, and chelating agents, polymers play an important role. As a matter of fact, those provide several benefits such as surfactant boosting, soil suspension, surface modification, dye transfer inhibition, etc. The use of polymers in laundry products has changed as detergent formulations have evolved. Initially, polycarboxylates, in the form of homo- and copolymers of acrylic acid or maleic acid, were introduced to replace sodium tripolyphosphate (being generally used as a builder) to address government regulations and restrictions. [2]. Form this positive result a wide spectrum of polymers for different purposes appeared. Currently, the attention is shifted towards the use of polymers as both soil removals and dispersants. Soil release or soil removals polymers are agents that have been developed as a consequence of the introduction of synthetic fibres into fabrics. Although the adoption of synthetic fibres (mostly polyester fibres) has led to more robust and resistant fabrics, it has also inevitably driven to a problem with oily stain. As a consequence, the employment of soil-release polymers is essential for both 100% polyester and cotton-polyester blends [3]. That said, the vast majority of synthetic polymers (mostly petrochemical-based) used in laundry detergents are toxicologically safe but not biodegradable. Concerns regarding the irreversible depletion of fossil resources, evolving government policies as well as environmental concerns, are driving the search for alternatives. For this reason, since natural polymers are renewable and largely biodegradable, they have recently found a great interest in the detergent industry.
Objective and methodology. This project aims to design, synthetise and characterise new soil-release agents starting from natural polymers. Several polysaccharide backbones will be explored. Those are selected from cellulose, inulin, chitosan, pullulan, xylan, scleroglucan and schizophyllan. Their properties will be tuned by chemical modifications. More specifically, various reagents (e.g., hydrophobic, cationic) will be wisely chosen in order to enhance or to provide specific characteristics to the final products, for instance, water-solubility, soil emulsification, etc. Various synthetic procedures will be pursued. Synthetic polymer derivates will be characterised by using a combined approach of several techniques. Specifically, NMR (nuclear magnetic resonance) and FTIR (Fourier-transform infrared spectroscopy) to understand derivates' microscopic architecture while conductimetric and potentiometric titration as well as elemental analysis to shed light on derivates' molecular composition. Soil release performances will be explored through in house tests. The relationship between the types of modification and soil release benefit will be then investigated. Lastly, the products' biodegradation profile will be monitored.

Bibliography
[1] Randall A. Watson, Laundry Detergent Formulations, in: Michael S. Showell (Ed.), Handbook of Detergents: Formulation, CRC Press LLC., 2009, pp. 51-103.
[2] Y.Yangxin1, Z. Jin, A. E. Bayly, Development of Surfactants and Builders in Detergent Formulations, Chin. J. Chem. Eng. 16(2008) 517-527.
[3] W. Bertleff, P. Neumann, R. Baur, and D. Kiessling, Aspects of Polymer Use in Detergents, J Surfactants Deterg. 1(1998) 419 - 424.