Chloroacetic acid (1.12 mmol, 2.0 equiv) was added to the reaction mixture and stirring continued for 12 hours at the same temperature.
Under alkaline conditions, chitosan can react with
chloroacetic acid to obtain the carboxymethyl chitosan.
The appropriate thiourea (1 mmol),
chloroacetic acid (1.2 mmol) and substitute thiophene-2-carbaldehyde (1 mmol) were stirred with a magnetic stirrer at 40 [degrees]C for 24 h.
Chemical MCL (mg/L) 500x (mg/L) Chloroform 22.39 Bromodichloromethane 12.98 Chlorodibromomethane 4.29 Bromoform 0.34
Chloroacetic acid 7.04 Dichloroacetic acid 13.52 Trichloroacetic acid 6.85 Bromoacetic acid 0.82 Dibromoacetic acid 1.77 Total THMs 0.08 40 Total HAAs 0.06 30 Total DBPs 70 Chemical 1,000x (mg/L) 2,000x (mg/L) Chloroform 44.77 89.54 Bromodichloromethane 25.96 51.92 Chlorodibromomethane 8.59 17.18 Bromoform 0.68 1.36
Chloroacetic acid 14.07 28.15 Dichloroacetic acid 27.03 54.06 Trichloroacetic acid 13.71 27.42 Bromoacetic acid 1.64 3.28 Dibromoacetic acid 3.54 7.09 Total THMs 80 160 Total HAAs 60 120 Total DBPs 140 280 Chemical proportions, based on those reported at the water utility that provided water for whole-mixture toxicity studies (Narotsky et al.
CMC is the product of the chemical reaction of cellulose with
chloroacetic acid under basic conditions (Figure 3).
CMC can be found vastly in plants from wood to renewable agricultural waste or biomass feedstock resources, [13] whereas chitosan was extracted from the external skeleton (shell) of marine crustaceans such as shrimp shells, crab shells and fungal mycelia [14] CMC is a linear anionic polysaccharide of anhydroglucose units linked by C-1 and C-4 ether bonds known as P-1,4 glycosidic linkages with extensive intramolecular hydrogen bonding, a cellulose derivative prepared from alkaline cellulose and
chloroacetic acid by etherification and usually used as its sodium salt (cellulose gum) [15].
Chloroacetic acid is used as an indirect additive in food contact substances, herbicide, preservative, and bacteriostat.