The present invention concerns a method for modifying a polysaccharide material, preferably an amylaceous material, involving a first step of homogeneous solubilisation of said polysaccharide material in an aqueous solvent, followed by a step of homogeneous chemical functionalisation comprising at least one non-crosslinking chemical modification, or at least one crosslinking chemical modification, or a sequence of at least one non-crosslinking chemical modification and at least one crosslinking chemical modification. Secondly, the present invention concerns a modified polysaccharide material, in particular obtained by the method according to the invention, characterised in that it has a novel distribution of the chemical substituents attached to the hydroxyl functions of the anhydroglucose units of said polysaccharide material. The novel starches can be used as organic adjuvants for dry mortars made from cement or made from gypsum, in particular as a binder for a dry mortar made from cement or as a thickening agent for a mortar made from plaster.

The present disclosure relates to charge-bearing polymeric materials and methods of their use for purifying fluid samples from micropollutants, such as anionic micropollutants.

The invention relates a process for preparing a cross-linked starch-based polymer comprising the following steps: 1) dissolving a starchy material in a suitable solvent to form a starchy material solution; and 2) adding a episulfide of formula (I), wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from hydrogen and (C.sub.1-C.sub.3)alkyl in the starchy material solution in order to obtain the disulfide crosslinked starch-based polymer. In another aspect the invention concerns a disulfide-cross-linked starch-based polymer obtainable by the process of the invention, that is characterized by only disulfide bridges.

Disclosed is a processing method of a self-reinforced starch-based multifunctional material, and belongs to the technical field of starch deep processing. The processing method takes bulk starch as a base material, including the following steps: firstly reacting starch nanoparticles with an organic acid anhydride reagent and adding a bacteriostatic agent to prepare composite nanoparticles, then mixing the composite nanoparticles with the bulk starch, an etherifying agent, a crosslinking agent, a plasticizer and the like, and finally preparing a starch-based multifunctional material by dry extrusion modification combined with a starch-based nanoparticle assembly and reinforcement technology. The method of the disclosure is simple and convenient in step, mild and controllable in reaction, and continuous and green in production. The obtained product has good mechanical properties, high barrier properties and high antibacterial properties, can be applied to many fields such as food, textiles, daily chemicals and medicine, and has a broad market prospect.

The invention relates a process for preparing a cross-linked starch-based polymer comprising the following steps: 1) dissolving a starchy material in a suitable solvent to form a starchy material solution; and 2) adding a episulfide of formula (I), wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from hydrogen and (C.sub.1-C.sub.3)alkyl in the starchy material solution in order to obtain the disulfide crosslinked starch-based polymer. In another aspect the invention concerns a disulfide-cross-linked starch-based polymer obtainable by the process of the invention, that is characterized by only disulfide bridges.

The present disclosure relates to charge-bearing polymeric materials and methods of their use for purifying fluid samples from micropollutants, such as anionic micropollutants.

Modified biopolymers, such as, charge-modified biopolymers, cross-linked biopolymers, and cross-linked, charge-modified biopolymers are provided along with methods of producing and using the same.

The present disclosure relates to pregelatinized starches having a high degree of process tolerance, and methods for making and using them. In one aspect, the disclosure provides a pregelatinized starch having no more than 15 wt % solubles and a sedimentation volume in the range of 15 mL/g to 45 mL/g, the pregelatinized starch comprising starch granules, wherein at least 50% of the starch granules swell but do not substantially fragment when processed in 95° C. water, the pregelatinized starch being in a substantially planar form. In another aspect, the disclosure provides a pregelatinized, drum-dried starch having no more than 15 wt % solubles and a sedimentation volume in the range of 15 mL/g to 45 mL/g, the pregelatinized starch comprising starch granules, wherein at least 50% of the starch granules swell but do not substantially fragment when processed in 95° C. water.

Disclosed is a preparation method of a starch-based hemostatic powder, comprising the following steps: (1) starch modification; (2) emulsification and crosslinking; (3) separation, purification, drying and sterilization. Provided is a starch-based hemostatic powder, which has a simple preparation process and a controllable cost. After being modified, raw material medical potato starch has a high degree of emulsification and crosslinking and a good and uniform spherical shape, and has a porous structure. Moreover, the product has good biocompatibility, low biological cytotoxicity, and obvious antibacterial effect; the product has a high liquid absorption ratio, and quickly forms a gel to cover the wound surface after liquid absorption, thus achieving a good hemostatic effect. The starch-based hemostatic powder is an excellent biomedical product, and can be used for clinical wound treatment, surgery to prevent organ adhesion, and bleeding from various wounds.

Modified biopolymers, such as, charge-modified biopolymers, cross-linked biopolymers, and cross-linked, charged modified biopolymers are provided along with methods of producing and using the same.