Isohexide and Sorbitol-Derived, Enzymatically Synthesized Renewable Polyesters with Enhanced T_g

Abstract

Sugar-based polyesters derived from sorbitol and isohexides were obtained via solvent-free enzymatic catalysis. Pendant hydroxyl groups, coming from the sorbitol units, were present along the polyester backbone, whereas the two isohexides, namely, isomannide and isoidide dimethyl ester monomers, were selected to introduce rigidity into the polyester chains. The feasibility of incorporating isomannide as a diol compared to the isoidide dimethyl ester as acyl-donor via lipase-catalyzed polycondensation was investigated. The presence of bicyclic units resulted in enhanced T g with respect to the parent sorbitol-containing polyester lacking isohexides. The different capability of the two isohexides to boost the thermal properties confirmed the more flexible character provided by the isoidide diester derivative. Solvent-borne coatings were prepared by cross-linking the sugar-based polyester polyols with polyisocyanates. The increased rigidity of the obtained sugar-based polyester polyols led to an enhancement in hardness of the resulting coatings.

Macroscopic Scaffold Control for Lipase‐Catalyzed Dendritic Polyol‐Polyesters

“…At present, glycerol and many other sugars like D‐sorbitol, D‐mannitol, and lactose have been polymerized with diacids/diesters, especially with divinyl esters in polar solvent(e.g., tetrahydrofuran or acetonitrile), which is preferred in achieving high molecular weights. Among those sugars, D‐sorbitol shows absolute advantages in reactivity, thus gradually becoming the most frequently used sugar in lipase catalysis . However, it is still challenging to have structurally well‐defined sorbitol‐based polyesters since there are so many primary and secondary hydroxyls on its backbone.…”

“…Among those sugars, D-sorbitol shows absolute advantages in reactivity, [22] thus gradually becoming the most frequently used sugar in lipase catalysis. [23][24][25] However, it is still challenging to have structurally well-defined sorbitol-based polyesters since there are so many primary and secondary hydroxyls on its backbone. Glycerol-based polyesters are also prevailing except that only randomly branched scaffolds can be given (polydispersity index (PDI) > 3).…”

Products of sugar beet processing as raw materials for chemicals and biodegradable polymers

“…This alcohol is mainly used as a food additive, successfully replacing traditional sugar due to its greater sweetness and lower caloric value in comparison to sucrose. Sorbitol is also used in other branches of industry: in medicine (for the production of vitamin C, bacterial culture media and medicines 145,146 ); in pharmaceutics (as a sweetener in syrups, toothpaste and mouthwashes [147][148][149] ); in the chemical industry (as a chemical platform for the synthesis of many valuable chemicals 150,151 or in polymerization processes [152][153][154] ) and in cosmetics (in emulsions, moisturizers and lotions 155,156 ). Sorbitol can be produced by the hydrogenation of an equivalent mixture of fructose and glucose in a temperature range of 120-160 C over RANEY® nickel catalyst.…”

Synthesis of hydroxyl‐bearing polyurethanes from naturally occurring myo‐inositol

“…Such targets meet the current need to reduce the consumption of fossil fuel feedstocks, as well as the evolution of carbon dioxide, which is vital to making society more sustainable . Among the various high‐performance polymers synthesized from naturally occurring compounds so far, those synthesized from monosaccharide‐derived diols, such as isohexides and bis‐acetals of hexitols, which bear cyclic, and thus, rigid cores, have attracted much attention, because these diols are versatile substrates for polycondensation and polyaddition. Furthermore, the resulting polymers, such as polyesters and polyurethanes, exhibit high glass transition temperatures because of the incorporation of the rigid cores in the repeating units of the polymer.…”