EARTH-FRIENDLY LIQUID LAUNDRY DETERGENTS FOR WASHING MACHINES

The use of washing machines in India and third world countries is increasing very fast. Special ecofriendly moderate foaming and high efficiency liquid laundry detergents must be developed which are moderate in cost yet effective in performance. In the present work efficient polymeric surfactants based mainly on sorbitol, polyethylene glycol and oxalic acid have been synthesized. The polymeric synthesis process has been standardized properly so that we can use it in washing machines detergents. The physicochemical and spectral properties of polymers suggest its selection in liquid detergent formulations. Liquid detergents were formulated using 14to20 % of this novel polymer along with other conventional ingredients. The prepared compositions were compared with commercial liquid laundry detergents. The result suggests use of this formulation on pilot plant & commercial scale. INTRODUCTION cleaning compositions like powder, cake and liquid detergents, floor and glass cleansers, utensil cleansers are based mainly on linear alkyl benzene sulphonate (LABS) or alpha olefin sulphonate (AOS) which are of petroleum origin. The total dependence of various cleansing preparations on petroleum products is not a wise investment and we must develop earth-friendly surfactants which can partly or totally replace active materials of petroleum origin. We have successfully developed polymers based on sorbitol, glycerol, malenized oil and starch for powder and liquid detergents. In the present work the intention is to develop high efficiency active material which will give moderate foaming (High foaming is totally undesirable for washing machine) and excellent performance characteristics. A special polymer has been synthesized based on sorbitol, polyethylene glycol (400) and oxalic acid. The polymers were systematically analyzed for their acid value, viscosity, surface tension and other physicochemical properties. The selected polymers (14-20%) were used for preparation of moderate foaming liquid laundry detergents for washing machine. The liquid laundry detergents were analyzed systematically along with a commercial product for foaming, surface tension and soil stain removal by standard methods 1-4 describe in the literature. The special feature of product is freedom from sodium tripolyphosphate which is source of pollution and use of sorbitol which gives a soothing and non-irritating feel to the skin. EXPERIMENTAL Synthesis of novel polymer- The preparation of novel polymer was carried out in a glass reactor. The reactor consists of two parts. Lower part of the reactor is a round bottom glass vessel with very wide mouth having capacity of about 2 liters. The upper part of the reactor is its lid, having four necks with standard joints. The central neck has a stirrer with speed regulator arrangement. The second neck is used for mounting thermometer. A condenser is fitted with the reactor through the third neck, and the fourth neck is used for dropping the chemicals into the reactor. An electric heating mantle is used for heating the reactants. A regulator controlled the speed of the stirrer. The reaction vessel and its lids are tied together with the help of clamps. Initially, composition of reactants (Table-1) was added in the reactor. The temperature was raised slowly to 130 0 c. The reaction was continued for 3 hours. The consistency of the paste was maintained by adding water. At the end of this period the batch was terminated and prepared polymer was collected in a glass stoppered bottle with least air gap. The final yield of the product was measured. Table-1 Composition of special polymers based on sorbitol and Polyethylene glycol. S. No. Raw material Concentration