This invention provides a preparation, composition, product, and application of a photo-coupled synergistically crosslinked hydrogel material. The preparation includes dissolving Component A including a photosensitive polymer derivative having o-nitrobenzyl phototriggers and Component B including a polymer derivative having amine or alkene (double group) or sulfhydryl group in a biocompatible medium to obtain solution A and solution B, respectively; mixing the solution A and solution B homogeneously to obtain a hydrogel precursor solution; initiating photo-coupled synergistic crosslinking under an irradiation of a UV light to form the hydrogel. The irradiation causes the o-nitrobenzyl phototriggers to generate an aldehyde group/keto group or a nitroso group to initiate photo-coupled synergetic crosslinking. The photo-coupled synergistically crosslinked hydrogel has applications in tissue engineering, regenerative medicine, 3D printing and as a carrier of cell, protein or drug.

A hydrophobized nanofibrillated cellulose foam comprising a charged hydrophobic amine, a method for providing such foam and its use.

The present invention provides a method of producing a polymer hydrogel comprising the steps of: (1) preparing an aqueous solution of a water soluble polysaccharide derivative and a polycarboxylic acid; (2) optionally agitating the solution, for example, by stirring; (3) isolating a polysaccharide derivative/polycarboxylic acid composite from the solution; and (4) heating the polysaccharide derivative/polycarboxylic acid composite at a temperature of at least about 80 C., thereby cross-linking the polysaccharide with the polycarboxylic acid. The invention also provides polymer hydrogels produced by the methods of the invention.

Methods and systems of the present invention use mixed textile feedstock, which may include post-consumer waste garments, scrap fabric and/or other textile materials as a raw feed material to produce isolated cellulose and other isolated molecules having desirable properties that can be used and be used in the textile and apparel industries, and in other industries. A multi-stage process is provided, in which mixed textile feed material is subjected to one or more pretreatment stages, followed by at least two pulping treatments for isolating cellulose molecules and other molecular constituents, such as polyester. The isolated cellulose and polyester molecules may be used in a variety of downstream applications. In one application, isolated cellulose and polyester molecules are extruded to provide regenerated cellulose fibers and regenerated polyester fibers having desirable (and selectable) properties that are usable in various industrial applications, including textile production.

A water- and oil-proofing composition which can provide an article with high utility oil resistance is provided. A water- and oil-proofing composition comprising a fluorinated polymer comprising units based on the following monomer (a) and units based on the following monomer (b), a fatty acid ester of polyglycerin and an aqueous medium: Monomer (a): a compound represented by CH.sub.2CHR.sup.f (wherein R.sup.f is a C.sub.1-8 perfluoroalkyl group). Monomer (b): a monomer copolymerizable with the monomer (a).

The present invention relates to a composite powder, in particular suitable for additive manufacturing, wherein said composite powder comprises composite particles comprising:at least one polymer matrix chosen among polyhydroxyalkanoates (PHA), andat least one auxiliary matrix chosen among biobased fillers and biobased waxes.

The invention concerns a method for depositing nano-objects on the surface of a gel comprising a polymer matrix having at least two contiguous zones of distinct rigidities, said method comprising the steps of: a) providing a gel comprising a polymer matrix and a solvent within the polymer matrix, the polymer matrix forming a three-dimensional array capable of swelling in the presence of said solvent, wherein the solubility of the polymer matrix, at 1 bar and 25 C., in the solvent is less than 1 g/L, the polymer matrix comprising at least two contiguous zones of distinct rigidities having a rigidity gradient greater than or equal to 0.1 kPa/m, then b) depositing nano-objects on the surface of the gel, then c) evaporating the solvent from the gel at least until the variation of the rate of evaporation of the solvent from the at least one least rigid zone of the gel is not constant over time, by which the nano-objects migrate towards the at least one most rigid zone of the gel and a gel is obtained for which the surface is at least partially coated with nano-objects, and wherein the density per unit area of nano-objects of the at least one most-rigid zone among the at least two contiguous zones is greater than that of the at least one least-rigid zone among the at least two contiguous zones, the gel that can be obtained and its applications.