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A successful protocol has been developed for the microwave assisted conversion of corn starch into 5hydroxymethylfurfural (HMF) utilizing aluminum chloride hexahydrate (AlCl 3 •6H 2 O) and 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) ionic liquid. HMF yield as high as 59.8 wt % was achieved at 150 °C within a short reaction time of 20 min. The dimethyl sulfoxide (DMSO)/[BMIM]Cl system was found to be tolerant to optimal water content which influenced the product distribution. Levulinic acid was detected in negligible quantities, and humin content could be controlled by varying different process parameters. Satisfactory results were achieved when waxy corn starch (HMF yield 64.9 wt %) and high amylose corn starch (HMF yield 51.1 wt %) were compared as potential feedstock alternatives to fructose and glucose. The work provided significant insight into the synthesis of HMF in a microwave environment from sustainably sourced biomass such as starch having high amylopectin content.

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An in-depth review on the catalytic transformation of starch to a remarkable breadth of products is discussed. The physicochemical properties of starches from different varieties are reported to influence their functionality. However, the impact of such properties on the reaction parameters for the cost-effective production of selective chemicals is largely unexplored. With the emergence of ionic liquids as the reaction media, water insoluble starch biopolymer can be easily dissolved and converted to reaction products simultaneously. Furthermore, microwave assisted chemical synthesis is known to enhance the reaction rates and optimize the resultant product selectivity. Physical and chemical modifications of starch also plays a vital role in the production of commodity chemicals. Recently, the potential routes to the production of biochemicals from biomass like glucaric acid, 5-hydroxymethyl furfural, 2,5-diformylfuran, 2,5-furandicarboxylic acid, 2,5-dimethylfuran, levulinic acid and sorbitol have been studied. Similar promising routes from inexpensive starches are analyzed in the review, as a function of the challenges associated to their chemical pathways and scalability.

Starch maleate/polylactic acid blends could replace polyethylene terephthalate in food packaging films. These films, however, are not acceptable for commercial use due to their poor performance, which is caused by processing polylactic acid with starch maleates having a low degree of maleic anhydride substitutions (DSNMR < 0.1 or DStitration < 1). Conventionally produced starch maleates produced via dry grinding or as aqueous and nonaqueous dispersions acquire a low DS due to the presence of inactive hydroxyl and maleic anhydride groups in each of the reaction systems. Low-DS starch maleates could barely interact with polylactic acid and plasticizers during blend processing; consequently, the resultant films perform poorly in terms of ductility and compostability. The key findings of this perspective indicate that recyclable ionic liquids like 1-allyl-3-methylimidazolium chloride could disrupt H-bonds among hydroxyls of starch and catalyze in situ maleic anhydride ring openings to provide functional groups for the synthesis of high-DS starch maleates (DSNMR ≥ 0.1 or DStitration ≥ 1). Improved interfacial chain interactions between high-DS starch maleates/polylactic acid and plasticizers like epoxidized soybean oil could facilitate stress-transfer and enzymatic activities of the resultant film, potentially improving its ductility and compostable properties. Besides these promising findings, this perspective also emphasizes the need for further research into identifying a wide range of ionic liquids and compostable plasticizers for producing high-DS starch maleates/polylactic acid blends, assessing the effect of interfacial chain interactions on properties of the resultant film, and determining specific usage of the film based on the barrier properties measured using standardized techniques.