Patent classifications
C08B11/02
SYNTHESIS OF A BIOCOMPATIBLE, BIODEGRADABLE, AND TUNABLE SHAPE MEMORY POLYMER TRIGGERED AT BODY TEMPERATURE
The present invention is a method to produce a biodegradable thermally induced shape memory polymer (SMP) based on poly(ε-caprolactone) (PCL) and ethyl cellulose (EC). In this synthesis method, after grafting the PCL on the linear EC, the PCL chains are end-functionalized with furan and maleimide moieties. The cross-linked network is prepared via Diels-Alder (DA) reaction between furanyl and N- maleimidyl PCL chains. The synthesized SMP demonstrates excellent shape memory properties at near body temperature (41° C.). Moreover, the polymer network is recyclable and re-processable, since the DA reaction is thermally reversible. The SMP of the present invention is well suited for numerous applications, especially in medical devices, given their excellent shape memory performance, tunable materials properties, body temperature-based stimulus, biocompatibility, and potential for biodegradation and resorption.
Crosslinked proppant-gel matrix
A method of making a proppant-gel matrix comprising: a) hydrating a gelling agent to form a hydrated gelling agent; b) adding a basic compound to the hydrated gelling agent to form a basic hydrated gelling agent having a pH in the range of 11.5 to 14.0; c) mixing the basic hydrated gelling agent and a proppant to form a basic hydrated gelling system; and d) adding a crosslinking agent to the basic hydrated gelling system to form the proppant-gel matrix, is disclosed. The proppant-gel matrix can then be used as a fracturing fluid in a hydraulic fracturing process.
Crosslinked proppant-gel matrix
A method of making a proppant-gel matrix comprising: a) hydrating a gelling agent to form a hydrated gelling agent; b) adding a basic compound to the hydrated gelling agent to form a basic hydrated gelling agent having a pH in the range of 11.5 to 14.0; c) mixing the basic hydrated gelling agent and a proppant to form a basic hydrated gelling system; and d) adding a crosslinking agent to the basic hydrated gelling system to form the proppant-gel matrix, is disclosed. The proppant-gel matrix can then be used as a fracturing fluid in a hydraulic fracturing process.
AMPHIPHILIC POLYSACCHARIDES, POLYSACCHARIDE-BASED HYDROGELS, AND METHODS OF MANUFACTURE
A method for the synthesis of alkyl ω-carboxy(hydroxyethyl) polysaccharides is described. The method includes methylating or ethylating a polysaccharide or providing a methylated or ethylated polysaccharide, hydroxyethylating the methylated or ethylated polysaccharide, and oxidizing the hydroxyethylated polysaccharide to form the ω-carboxy(hydroxyethyl) polysaccharide. A method for the synthesis of oxidized polysaccharides is also described. The method includes hydroxypropylating a polysaccharide and oxidizing the hydroxypropylated polysaccharides. A method for the production of a solid capable of forming a hydrogel is also described. The method includes combining a first solution comprising an oxidized oligo(hydroxypropyl) polysaccharide bearing one or more ketone groups with a second solution comprising an amine substituted polysaccharide to form a third solution, and removing solvent from the third solution to form the solid, or adding an additional solvent to the third solution to precipitate the solid. Novel polysaccharides and hydrogels prepared according to these methods are also described.
CROSSLINKED PULPS, CELLULOSE ETHER PRODUCTS MADE THEREFROM; AND RELATED METHODS OF MAKING PULPS AND CELLULOSE ETHER PRODUCTS
Pulps, cellulose ether products, and methods of making pulps are described.
Crosslinked proppant-gel matrix
A method of making a proppant-gel matrix comprising: a) hydrating a gelling agent to form a hydrated gelling agent; b) adding a basic compound to the hydrated gelling agent to form a basic hydrated gelling agent having a pH in the range of 11.5 to 14.0; c) mixing the basic hydrated gelling agent and a proppant to form a basic hydrated gelling system; and d) adding a crosslinking agent to the basic hydrated gelling system to form the proppant-gel matrix, is disclosed. The proppant-gel matrix can then be used as a fracturing fluid in a hydraulic fracturing process.
Crosslinked proppant-gel matrix
A method of making a proppant-gel matrix comprising: a) hydrating a gelling agent to form a hydrated gelling agent; b) adding a basic compound to the hydrated gelling agent to form a basic hydrated gelling agent having a pH in the range of 11.5 to 14.0; c) mixing the basic hydrated gelling agent and a proppant to form a basic hydrated gelling system; and d) adding a crosslinking agent to the basic hydrated gelling system to form the proppant-gel matrix, is disclosed. The proppant-gel matrix can then be used as a fracturing fluid in a hydraulic fracturing process.
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.
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).
Amphiphilic polysaccharides, polysaccharide-based hydrogels, and methods of manufacture
A method for the synthesis of alkyl ω-carboxy(hydroxyethyl) polysaccharides is described. The method includes methylating or ethylating a polysaccharide or providing a methylated or ethylated polysaccharide, hydroxyethylating the methylated or ethylated polysaccharide, and oxidizing the hydroxyethylated polysaccharide to form the ω-carboxy(hydroxyethyl) polysaccharide. A method for the synthesis of oxidized polysaccharides is also described. The method includes hydroxypropylating a polysaccharide and oxidizing the hydroxypropylated polysaccharides. A method for the production of a solid capable of forming a hydrogel is also described. The method includes combining a first solution comprising an oxidized oligo(hydroxypropyl) polysaccharide bearing one or more ketone groups with a second solution comprising an amine substituted polysaccharide to form a third solution, and removing solvent from the third solution to form the solid, or adding an additional solvent to the third solution to precipitate the solid. Novel polysaccharides and hydrogels prepared according to these methods are also described.