2.3.1 Methylated guar
Methylation of guar gum is an important tool to
know about the structure composition and constitution of polymer. Denham and
Woodhouse and Haworth method is consider
as standard method for methylation of
polysaccharides by using DMS in alkaline
condition. Methylation is done by nucleophilic
substitution mechanism. V. Singh et al. Fully
methylated GG by using the domestic
Microwave oven within 4min. They used dimethy sulphate as methylating agent and
sodium hydroxide as catalyst. Product formed
were analyzed by IR spectroscopy. Scheme
4A) D. Risica et al.performed etherification
of Guar by using dimethyl sulfoxide (DMS) and
methyl iodide (MI) with excess of sodium
hydroxide (NaOH).