The invention provides a crosslinked polymer, a hydrogel, a water-based fracturing fluid comprising the same, and methods of making and using thereof. The crosslinked polymer of the invention is represented by formula (I), wherein * denotes a combining site with a polymer starting material and * denotes an optional combining site with the polymer starting material, wherein the combining sites denoted by * and * may be located in the same polymer molecule, or in different polymer molecules, but there are at least two combining sites located in different polymer molecules; X.sub.1 and X.sub.2, which may be the same or different, are independently an oxy (O) or imino (NH) group; X.sub.3 is an oxy (O) or imino (NH) group when * denotes a combining site with the polymer starting material, or X.sub.3 is a halogen, NH.sub.2 or OH when * isn't a combining site with the polymer starting material. The crosslinked polymer of the invention can be used in water-based fracturing fluid, in personal care products, household care products and pet care products, in reusable hydraulic fracturing flowback fluid, in gel explosives or in fire extinguishing mortar.

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Microstructure manufacturing apparatuses and methods are disclosed herein that enable the production of microstructures in an efficient, cost-effective manner that produces precise, high-quality microstructure products. In the manufacturing process for a microneedle array, for example, a template can be contacted against a surface of a continuous layer of a viscous polymer and separated from the surface to form a plurality of projections. The projections can then be solidified and laser cut at a predetermined distance from the surface to form the microstructure.

A hydrogel of which the degradation is accurately controlled can be provided by a photodegradable hydrogel production method, the method comprising the steps of: reacting ?-glucan having a weight average molecular weight of 2000 to 200,000 with a compound represented by formula I to introduce a group represented by formula II into the ?-glucan; oxidizing the ?-glucan having, introduced therein, the group represented by formula II with periodic acid or a periodate salt to introduce an aldehyde group into the ?-glucan; and adding aminated carrageenan gel beads having polydopamine particles embedded therein to a gelling agent which has been prepared by introducing a group represented by formula II and an aldehyde group into ?-glucan, and then causing the crosslinking reaction of the resultant product with a polythiol-type reducing agent to form the hydrogel.

Disclosed herein are compositions comprising (i) an insoluble alpha-glucan and soluble alpha-glucan derivative, or (ii) an insoluble alpha-glucan and additive. These compositions can be in the form of particles, for example, such as particles comprising insoluble alpha-glucan coated with a soluble alpha-glucan derivative and/or additive. Methods are further disclosed for preparing these compositions, as well as various applications of using them.

Methods to prepare nanohydrogels are disclosed that include functionalizing a polysaccharide with a hydrophobic compound to form a functionalized polysaccharide, and subjecting the functionalized polysaccharide to a self-assembling process in a water environment for the formation of the nanohydrogel. The hydrophobic compound is riboflavin, or a derivative thereof, to which an alkyl group having a functional group suited to form a covalent bond with the polysaccharide has been bonded.

The present invention is directed toward a process for making a poly alpha-1,3-glucan film. These films can be transparent or translucent and used in packaging applications.

The present invention relates to a process for preparing a biocompatible and biodegradable, porous three-dimensional polymer matrix, to the porous polymer matrix obtained by means of such a process, and also to the uses thereof, in particular as a support and for cell culture or in regenerative medicine, and in particular for cell therapy, in particular cardiac cell therapy.

A method for preparing an improved gum arabic comprising the steps of providing a gum arabic from acacia seyal selecting gum arabic having a tannin content >700 ppm (w/w).

The present disclosure is directed to compositions including a microemulsion comprising lecithin, a polysorbate, an alkyl polyglycoside, and optionally a solvent. Uses of the microemulsions are also disclosed.

An object of the present disclosure is to provide a method for producing a polysaccharide nanofiber-blended polysaccharide composition whose mechanical physical properties are reinforced by a polysaccharide nanofiber, and is easily carried out. A method for producing a polysaccharide nanofiber-blended polysaccharide composition is also provided which includes a step of mixing a sol containing a polysaccharide nanofiber (A), a polysaccharide (B), and a solvent (C) capable of dissolving the polysaccharide (B), and a step of drying the resultant mixture to obtain a dry mixture.