Peculiarities of Starch Cationization with Glycidyltrimethylammonium Chloride

Abstract

Cationic starch derivatives containing quaternary ammonium groups with high degree of substitution are prepared by reaction of starch with glycidyltrimethylammonium chloride (GTAC) in different reaction media. In aqueous solutions of GTAC along with conventional hydrolysis of epoxy groups, their interaction with chloride ions also takes place. This resulted in formation of hydroxyl ions which accelerate both the hydrolysis of GTAC epoxy groups and can act as the internal catalyst in the reaction of GTAC with starch. Therefore, even in the absence of the external catalyst, cationic starch with a high degree of substitution can be obtained. The autocatalytic reaction of GTAC with starch proceeds more rapidly at higher temperatures but with lower reaction efficiency. Both in the absence of the external catalyst and in the case when sodium alkali is used as a catalyst the reaction of starch with GTAC proceeds only when a particular quantity of “free” water is present in the system. When the NaOH as catalyst is used the reaction efficiency is about 90%. The yield of starch cationization reaction decreases when the quantity of “free” water is twice or thrice higher than required for starch modification to begin.

New cationic hydrophilic and amphiphilic polysaccharides synthesized by one pot procedure

“…In all cases, the DS increases with increase in the ratio a/AGU, but the efficiency decreases in the order: (ii) > (iii) > (i). The higher efficiency of GTAC versus CHPTAC was previously shown for the starch quaternization (Bendoraitiene, Kavaliauskaite, Klimaviciute, & Zemaitaitis, 2006;Haack et al, 2002), and was explained by the competition between the main quaternization reaction and the CHPTAC enhanced inactivation due to the higher content in NaOH required for the procedure (i). The better performances of the procedure (iii) in comparison with (i) can be a supplementary proof of glycidyl derivative formation in situ, in the absence of NaOH.…”

Characterization of cationic parenchyma cellulose derivative by rapid preparation of low microwave power

“…This phenomenon may be explained by several reasons, as follows: Firstly, microwave enables direct heating of the target materials containing mobile electric charges, such as alkali cellulose and etherifying agent even in solid-state reaction, which permits forward reaction with less water or other polar solvents as compared to the conventional heating methods [42]. Thus the possibility of side-reaction hydrolysis given above is largely reduced and the GTMAC-utilized effectiveness is greatly enhanced.…”

“…Secondly, the GTMAC-based etherification can be easily evoked under mild conditions of microwave irradiation due to the low activation energy of its main reaction [29]. The microwave energies are lower than the Brownian motions, that is, microwave chemistry is based on efficient heating materials and not induction of chemical bond cleavage [42]. Consequently, it is more effective to prevent electromagnetic-radiation degradation of chemical reagents and cationic product by means of microwave irradiation.…”

Cationization of field pea starch in salt-free aqueous suspension

“…5, a starch concentration of 40% (w/w) resulted in a higher DS at both active amine/starch molar ratios in the pres- ence of 60% sucrose (starch solids basis), compared to the DS value obtained at a starch concentration of 30%. Research (Bendoraitiene, Kavaliauskaite, Klimaviciute, & Zemaitaitis, 2006) has pointed out that DS and RE decrease when the amount of available water is twice or thrice as high as that required to hydrate starch, dissolve the catalyst, diffuse the cationic reagent, and facilitate the swelling of the starch granule during the cationization process. The optimum starch/water ratio for an aqueous-alcoholic starch cationization process was approximately 1:1 (Kweon, Sosulski, & Bhirud, 1997).…”