There are provided a porous water-soluble nonionic cellulose ether having an average pore size of 36 m or smaller and an average particle size of from 30 to 300 m; and a method for continuously producing said cellulose ether comprising the steps of: pulverizing a first water-soluble nonionic cellulose ether to obtain a first pulverized product, and sieving the pulverized product through a sieve having an opening of from 40 to 400 m to obtain a first residue-on-sieve and a first sieve-passing fraction, wherein a portion or all of the first residue-on-sieve containing particles having particle sizes smaller than and greater than the opening of the sieve is re-pulverized together with a second water-soluble nonionic cellulose ether in the step of pulverizing to obtain a second pulverized product, which is pulverized to obtain the cellulose ether as a second sieve-passing fraction containing the re-pulverized particles.

Cellulose ether powder is prepared in a safe and easy way by first adding a surfactant solution to surfaces of water-soluble cellulose ether particles, and then adding a tannin solution thereto. The powder thus prepared is free of bitterness and readily dissolvable in cold water without forming clumps.

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.

A free standing film is provide, including: 20 to 100 wt %, based on weight of the free standing film, of an irreversibly crosslinked cellulose ether containing 0.1 to 0.6 wt %, based on weight of the crosslinked cellulose ether, of polyether groups. Unit dose packages including the free standing film are also provided.

Disclosed is a cellulose composition including: (A) a water-soluble cellulose ether, (B) water-insoluble cellulose particles and (C) water. The cellulose composition may serve as a novel biomass material which uses biodegradable cellulose that places little burden on the environment, and exhibits excellent shape retention properties. The cellulose composition may include (A) 100 parts by weight of the water-soluble cellulose ether, (B) 30 to 150 parts by weight of the water-insoluble cellulose particles, and (C) 300 to 1,000 parts by weight of water.

According to an example aspect of the present invention, there is provided an extrusion foaming method for producing low-density extrusion foam from a thermoplastic cellulose-based starting material.

Aspects of the present disclosure may include methods of preparing a cellulose-based aerogel including: preparing an alkali cellulose; reacting the alkali cellulose with an alkylating agent to form alkylated cellulose; mixing the alkylated cellulose with fibrillated cellulose comprising carboxyl groups in an aqueous solution to form a foam; and drying the foam to form a cellulose-based aerogel. Embodiments of the present disclosure may include a cellulose-based closed-foam aerogel, the closed-cell aerogel including: an alkylated cellulose; a fibrillated carboxylated cellulose; wherein the alkylated cellulose and the fibrillated carboxylated cellulose are mixed to foam, wherein the foam is capable of being dried under ambient conditions to form the closed-cell aerogel.