Patent classifications
C08B3/00
Cross-metathesized polysaccharide derivatives and processes for preparing them
Methods for the cross-metathesis of polysaccharides with one or more olefin-terminated side chains and cross-metathesized products are described. In an exemplary embodiment, a method for the synthesis of cellulose -carboxyesters via olefin cross-metathesis is described. Conditions of the reactions were relatively mild and the olefin-substituted polysaccharides and the appropriate monomeric olefin partners appear to follow Grubbs rules as summarized herein. The compounds and methods may be useful for structure-property studies, particularly those aimed at developing polymers for drug delivery, such as for controlled-release drug delivery systems, controlled-release coatings, increasing bioavailability of drugs, and maintaining drug supersaturation in the GI tract.
Cross-metathesized polysaccharide derivatives and processes for preparing them
Methods for the cross-metathesis of polysaccharides with one or more olefin-terminated side chains and cross-metathesized products are described. In an exemplary embodiment, a method for the synthesis of cellulose -carboxyesters via olefin cross-metathesis is described. Conditions of the reactions were relatively mild and the olefin-substituted polysaccharides and the appropriate monomeric olefin partners appear to follow Grubbs rules as summarized herein. The compounds and methods may be useful for structure-property studies, particularly those aimed at developing polymers for drug delivery, such as for controlled-release drug delivery systems, controlled-release coatings, increasing bioavailability of drugs, and maintaining drug supersaturation in the GI tract.
Functionalized cellulose nanocrystal materials and methods of preparation
The surface hydrophobization of cellulose nanocrystals (CNCs) by carboxylic acids, biodiesel, or plant oils was conducted via there herein disclosed green process using an one-pot synthetic method. In the process, an aqueous lactic acid syrup served as a solvent to provide a stable and well-dispersed water suspension of CNCs and participated in esterification reactions to produce an intermediate product of polylactic acid (PLA) oligomer grafted CNCs (CNC-g-PLA). This solvent and intermediate product system allows for an in situ solvent exchange from water to lactic acid without prior drying of the CNCs and a subsequent efficient esterification reaction of CNCs with carboxylic acids or esters having a long hydrocarbon chain (FAs). Another advantage of the disclosed process is the ability to reuse the reagents in the subsequent reaction in order to reduce the production cost. Grafting of renewable materials on the surface of CNCs was developed by polyesterification that is capable of being environmentally friendly and mass-produced without any organic solvents or toxic reagents.
Functionalized cellulose nanocrystal materials and methods of preparation
The surface hydrophobization of cellulose nanocrystals (CNCs) by carboxylic acids, biodiesel, or plant oils was conducted via there herein disclosed green process using an one-pot synthetic method. In the process, an aqueous lactic acid syrup served as a solvent to provide a stable and well-dispersed water suspension of CNCs and participated in esterification reactions to produce an intermediate product of polylactic acid (PLA) oligomer grafted CNCs (CNC-g-PLA). This solvent and intermediate product system allows for an in situ solvent exchange from water to lactic acid without prior drying of the CNCs and a subsequent efficient esterification reaction of CNCs with carboxylic acids or esters having a long hydrocarbon chain (FAs). Another advantage of the disclosed process is the ability to reuse the reagents in the subsequent reaction in order to reduce the production cost. Grafting of renewable materials on the surface of CNCs was developed by polyesterification that is capable of being environmentally friendly and mass-produced without any organic solvents or toxic reagents.
VARIABLE-SIZE HYDROPHOBICALLY-MODIFIED POLYMERS
In various aspects, the invention provides compositions of variable-length hydrophobically-modified polymers. These variable-length hydrophobes decorated along the hydrophilic polymer backbone provide advanced properties and allow for precise control over the behavior of the resulting amphiphilic polymer, including in aqueous solution. Such control allows for enhanced functionality of the amphiphilic polymer relative to standard single-length hydrophobe grafting designs, including for hemostasis.
POLYLACTIDE-GRAFTED CELLULOSE NANOFIBER AND PRODUCTION METHOD THEREOF
Provided are a polylactide-grafted cellulose nanofiber that is suitable as a molding material, and a production method thereof. A polylactide-grafted cellulose nanofiber includes grafted cellulose having a graft chain bonding to cellulose constituting a cellulose nanofiber, wherein the graft chain is a polylactide, and a ratio of an absorbance derived from CO of the polylactide to an absorbance derived from OH of the cellulose on an infrared absorption spectrum is no less than 0.01 and no greater than 1,000. In addition, a production method of a polylactide-grafted cellulose nanofiber includes carrying out graft polymerization of a lactide to cellulose constituting a cellulose nanofiber in the presence of an organic polymerization catalyst which includes an amine and a salt obtained by reacting the amine with an acid. As the organic polymerization catalyst, 4-dimethylaminopyridine and 4-dimethylaminopyridinium triflate are preferred.
HYDROPHOBICALLY MODIFIED CHITOSAN COMPOSITIONS
Disclosed herein is a polymer composition comprising an effective amount of a hydrophobically-modified polymer having functional groups along the backbone occupied by a fatty anhydride moiety. The polymer composition has a potent hemostatic action by gelling blood upon contact, and is suitable for treating internal and external bleeds. As disclosed herein, the modified polymer can be generated without the use of toxic reagents that would require removal from the product. Further, compositions are shelf stable even in a flowable form. That is, the hydrophobic grafts are not lost under product storage conditions (e.g., room temperature storage).
CELLULOSE ESTER OPTICAL FILMS
Regioselectively substituted cellulose esters having a plurality of aryl-acyl substituents and a plurality of alkyl-acyl substituents are disclosed along with methods for making the same. Such cellulose esters may be suitable for use in optical films, such as optical films having certain Nz values, A optical films, and/or +C optical films. Optical films prepared employing such cellulose esters have a variety of commercial applications, such as, for example, as compensation films in liquid crystal displays and/or waveplates in creating circular polarized light used in 3-D technology.
Acylation process
The invention concerns a process for the manufacture of an acylated polymer composition comprising amylose and/or amylopectin, comprising a pre-treatment step in the presence of an acid, a salt and a polycarboxylic acid, subsequent acylation and, preferably, a post-treatment step with an acid. The products obtained are useful as additives in inks, varnishes, lacquers, coatings, thickeners, adhesives or binders.
Acylation process
The invention concerns a process for the manufacture of an acylated polymer composition comprising amylose and/or amylopectin, comprising a pre-treatment step in the presence of an acid, a salt and a polycarboxylic acid, subsequent acylation and, preferably, a post-treatment step with an acid. The products obtained are useful as additives in inks, varnishes, lacquers, coatings, thickeners, adhesives or binders.