Study of the Crosslinking Reaction between Epichlorohydrin and Starch

Abstract

The crosslinking of starch with epichlorohydrin under homogeneous and heterogeneous conditions has been studied with a particular view of measuring the extent of the side reaction wherein epichlorohydrin is substituted on the starch as a monoether derivative. The extent of this reaction, compared to the diether crosslink, was found to be strongly dependent on the reaction conditions (temperature, time, mole ratio of all reactants) and depending on these from 5 – 25 % of the applied epichlorohydrin is bound in the resulting product as a glycerol monoether substituent. The degree of swelling of the crosslinked starch was shown to be linearly dependent on the molar ratio of water to starch in the reaction mixture. It is shown that starch crosslinking proceeds with remarkable efficiency when epichlorohydrin is applied in the vapour phase. When crosslinking is performed under conditions which maintain the native granule structure the extent of monoether formation is about the same as for homogeneous crosslinking conditions.

Characterization of crosslinked starch materials with spectroscopic techniques

“…Abundant information on this reaction can be found in the literature. However, although the crosslinking reaction between EPI and polysaccharides has been known for 80 years, 1 some basic questions concerning this reaction continue yet to interest the scientific community.…”

Citric acid cross-linking of starch films

“…Starch and starch products have been cross-linked with cross-linking agents, such as phosphorus oxychloride, sodium trimetaphosphate, sodium tripolyphosphate, epichlorohydrin, and 1,2,3,4-diepoxybutane, to improve the mechanical properties and water stability of starch products (Hirsch and Kokini, 2002;Kunaik and Marchessault, 1972;Seker and Hanna, 2006;Simkovic et al, 2004;Wattanachant et al, 2003). In addition to cross-linking, blending starch with synthetic polymers has also been considered to improve the performance of starch products.…”

Mechanism of dialkyl phthalates removal from aqueous solution using γ-cyclodextrin and starch based polyurethane polymer adsorbents

“…The presence of the hydroxyl group makes chemical modification easy (Imam et al, 2012;Okoli, Guo, & Adewuyi, 2014). Among various starch and cyclodextrin polymers, the cross-linked polymers have been the most investigated adsorbents due to their total biodegradability, biocompatibility, non-toxicity, cost effectiveness, stability on storage, as well as simple fabrication method (Kuniak & Marchessault, 1972;Simkovic, Laszlo, & Thompson 1996;Datskevich, 2009;Guo, Li, Liu, Yin, & Li, 2009). Due to the host-guest interaction property of cyclodextrins, their polymers have been extensively studied for water remediation (Mohamed, Wilson, & Headley, 2010).…”