15 results about "Cellulose microfibril" patented technology

The invention discloses a cellulose-based aerogel with dynamic adjustable electromagnetic wave absorption performance and a preparation method thereof.The preparation method comprises the steps that cellulose nanofibers are assembled into cellulose microfibers through physical ice crystal extrusion, a conductive / magnetic conductive path is built by adding functional components, the preparation technology and composition of the cellulose-based aerogel are optimized, and the cellulose-based aerogel with the dynamic adjustable electromagnetic wave absorption performance is obtained. The cellulose-based aerogel with excellent elastic property is constructed, and the adjustable electromagnetic property and the dynamically adjustable electromagnetic wave absorption property under strain amplitude driving are realized. The problems that a traditional electromagnetic wave absorption aerogel material can only work in a specific electromagnetic wave frequency band, and the electromagnetic wave absorption characteristic is difficult to adjust according to scene requirements are solved.

To provide a manufacturing method of a concentrate of a cellulose fine fiber dispersion, capable of manufacturing a concentrate with suppressed variation of solid fraction with low environmental load even when using a thin cellulose fine fiber dispersion.SOLUTION: Disclosed is a manufacturing method of a concentrate of a cellulose fine fiber dispersion, including a concentration process of deliquoring the cellulose fine fiber dispersion to obtain the concentrate, in which: an average fiber diameter of cellulose fine fibers in the cellulose fine fiber dispersion is 50-1000nm; in the concentration process, the cellulose fine fiber dispersion is subjected to deliquoring continuously at a processing speed of 1.0 kg-DS / h or over and under 45.0 kg-DS / h; in the concentration process, when measuring a solid fraction of the concentrate in a 10-times sampling, an average value of the solid fraction is 5 wt.% or over and 60 wt.% or under, and a CV value (standard deviation / average value) of the solid fraction is 0.001 or over and 0.300 or under.SELECTED DRAWING: Figure 3

The invention discloses a bamboo cellulose micro-nano fiber composite aerogel material and a preparation method and application thereof, and relates to the field of aerogel, the preparation method comprises the following steps: S1, crushing bamboo pulp to obtain bamboo pulp microfibers; s2, adding the bamboo pulp microfiber and bamboo cellulose nanofiber suspension into water, and stirring; s3, sequentially adding silicon dioxide, polysiloxane and boric acid into the dispersion liquid to obtain a premix; s4, adding a polyvinyl alcohol aqueous solution and a glutaraldehyde aqueous solution at room temperature to obtain a reactant; s5, pouring reactants into a mold, and freezing and forming to obtain ice gel; and S6, replacing the ice gel with ethanol, and drying at normal pressure to obtain the composite aerogel material. According to the method, cellulose does not need to be dissolved, cellulose microfibers serve as a firm framework, interpenetrating double networks are constructed through physical entanglement, physical / covalent cross-linking and ice crystal template constraint, multi-scale material interface assembly is achieved, and the composite material can be easily prepared under normal-pressure drying and is expected to serve as a sustainable substitute of plastic foam.

The invention belongs to the technical field of synthetic biology and biological materials, and particularly relates to a cellulose synthetase high-efficiency expression system based on a cell membrane adaptation strategy, and a preparation method and application of cellulose microfibrils. The method is used for efficient heterologous expression of cellulose synthetase subunits PtCesA1 and PtCesA8 from populus trichocarpa, and in-vivo synthesis of cellulose microfibrils is realized. The key enzyme NMT of a phosphatidylcholine synthesis route is introduced to modify the escherichia coli cell membrane lipid composition, so that the expression efficiency and the cellulose synthesis capability of the eukaryotic-source membrane protein are remarkably improved. Further, the cellulose yield is remarkably increased by systematically optimizing culture conditions such as concentration, temperature and time of the inducer. The system constructed by the invention can be used for directly synthesizing cellulose microfibrils with an ordered structure and high purity in escherichia coli, and a new path is provided for green biological manufacturing of cellulose.

The application relates to a cotton fiber strength major gene NTL9 BS41 and application thereof. Through cotton transgenic technology, NTL9 BS41 is successfully introduced into Gossypium hirsutum and high expression of the gene in cotton fibers is realized, the fiber strength of cotton is significantly enhanced without negative influence on other fiber qualities, overexpression of NTL9 BS41 can effectively enhance the density and uniformity of cellulose microfibril accumulation, and the structure and performance of cotton fibers are significantly optimized. In addition, the gene is derived from Gossypium barbadense, compared with Gossypium hirsutum, there is an insertion type variation of 24 bp nucleotides in the CDS of the gene, and a molecular marker capable of effectively distinguishing Gossypium hirsutum and Gossypium barbadense haplotypes is successfully developed. The application provides new gene resources, technical means and germplasm resources for cotton fiber quality improvement, and has far-reaching application value and potential for promoting the progress of cotton breeding work.

Provided is a method for producing type II unmodified cellulose microfibers, which is a method for producing cellulose microfibers by mercerizing cellulose, and which can efficiently produce unmodified cellulose microfibers by a simple process. The method for producing type II unmodified cellulose microfibers is characterized by having the following steps: a defibrillation step in which defibrillation is performed by adding an alkali metal hydroxide to raw material cellulose subjected to a mercerization step of mercerizing cellulose to obtain mercerized cellulose and a depolymerization step of reducing the degree of polymerization of the mercerized cellulose to 760 or less, such that the total concentration is 2.5 to 17.5%, thereby obtaining cellulose microfibers; and a neutralization step in which the cellulose microfibers are neutralized with an acid.

Provided is a raw material having an anti-contamination effect. Cellulose microfibers are used as an additive for an anti-pollution external skin preparation having an anti-pollution effect. In addition, an anti-pollution external preparation for the skin is provided using the additive. The cellulose microfibers are preferably chemically modified cellulose microfibers.

Provided are cellulose microfibers (fibrous cellulose) that can be used in a general-purpose manner for a variety of applications and that have a uniform fiber diameter distribution and a low proportion of both cellulose nanofibers and coarse structures, a composition containing said cellulose fibers, and a porous body composed of said cellulose fibers. The present invention relates to cellulose fibers in which the average fiber diameter in a dry state is 0.3-3.0 um as observed using an electron microscope, the proportion of fibers having a fiber diameter of less than 0.1 um is 5% or less, and the proportion of coarse structures as indicated by the proportion of fibers having a wet fiber diameter of 20 um or greater measured through automatic optical analysis is 3.0% or less. The present invention also relates to a composition containing said cellulose fibers, and a porous body composed of said cellulose fibers.

A liquid fertilizer composition includes an aqueous phase, dispersed cellulosic fibers including carboxylated cellulose microfibers and / or carboxylated cellulose nanofibers, dissolved nitrogen that includes nitrate and optionally ammonium, dissolved phosphorus, dissolved potassium, oxidized organic carbon compounds, and a nitro-oxidized effluent.

The invention discloses a method for preparing high-purity xylooligosaccharide from low-concentration trifluoroacetic acid in cooperation with xylanase, and belongs to the technical field of bioactive substance conversion. The method comprises the following steps: crushing and sieving a wood fiber raw material, mixing with trifluoroacetic acid, carrying out a catalytic reaction, carrying out rotary evaporation to recover trifluoroacetic acid, adding xylanase into a residual solid-liquid mixture, carrying out an enzymatic hydrolysis reaction, carrying out solid-liquid separation, and carrying out enzyme inactivation, filtration, decoloration, concentration treatment and spray drying on enzymatic hydrolysate to obtain xylooligosaccharide powder. The used trifluoroacetic acid permeates into the raw materials, hydrolyzes ester bonds and hydrogen bonds between hemicellulose and lignin, part of low-molecular-weight xylan and lignin are dissolved, wrapped cellulose microfibers are exposed, the structure of the raw materials becomes loose and porous, the accessibility is greatly improved, trifluoroacetic acid has high volatility, and the preparation method is suitable for industrial production. The xylooligosaccharide can be recycled through distillation, so that the cost and the product purification difficulty are reduced, and the purity of the xylooligosaccharide product is improved.

To provide fine cellulose fiber, the dispersion of which has very high transparency and viscosity, and a method for producing the fine cellulose fiber. In the cellulose fiber, a part of hydroxy groups of cellulose fiber is substituted with a predetermined functional group to introduce an ester of phosphorus-oxo acid, and substituted with a carbamate group to introduce a carbamate. The method for producing fine cellulose fiber includes adding an additive (A) and an additive (B) including at least one of urea and a urea derivative to cellulose fiber, heating the mixture at 100 to 210°C, washing the mixture, and then fibrillating the mixture, the additive (B) being added in an amount of 0.01 to 100 mol based on 1 mol of the additive (A).

Various techniques for generating nanocellulose are described. An example method includes generating a first material by performing alkaline peroxide pulping on heterogenous biomass; generating a second material by removing at least a portion of a dissolved lignin fraction from the first material; and generating a third material by performing mechanical fibrillation on the second material. A fourth material is generated by performing an oxidation pretreatment on the third material. A fifth material is generated by performing mechanical fibrillation on the fourth material. The fifth material includes lignocellulosic microfibrils (LCMF) having a dimension in a range of about 10 to about 1,000 nanometers (nm) and / or lignocellulosic nanofibrils (LCNF) having a dimension in a range of about 1 to about 10 nm.

The invention discloses a novel wood-like flower box production process. The novel wood-like flower box production process comprises the steps of S1, material pretreatment; S11, alkali treatment, wherein lignin is removed, and cellulose microfibrils are exposed; s12, silane coupling: immersing the wood chips into a 3% KH-550 silane solution, adjusting the pH value to 5.5, and reacting at room temperature for 6 hours; s2, mixed material preparation: mixing 12-15 parts of modified wood chips, 40-50 parts of Portland cement, 0.5-1 part of nano calcium carbonate, 0.5 part of chopped glass fiber, 1-1.25 parts of a polycarboxylic acid water reducer and a proper amount of iron oxide pigment; s3, mold design: S31, mold building; s4, pouring and forming: S41, preparing the mixed material into slurry; s42, the slurry is poured into the cavity, and bubbles are removed through a vibration table; s5, forming and curing; S51, pre-curing; s52, carrying out steam curing; and S6, bionic surface treatment: performing surface pyrolysis on the surface of the flower box to form a rough wood grain surface with Ra of 15 microns. Through the process steps, the wood-like flower box which is high in simulation degree and durable is produced.

This invention relates to a high-strain, tough, recyclable all-cellulose double-hydrogen-bonded network bioplastic, its preparation method, recycling method, and applications, belonging to the field of bio-based materials. It includes: strong hydrogen bonds connecting cellulose microfibers and regenerated nanocellulose; weak ionic hydrogen bonds connecting chloride ions and the regenerated nanocellulose; and lithium ions used to maintain electrical balance. The strong and weak ionic hydrogen bonds together construct a multi-level hydrogen bond system with a double-network hydrogen bond structure. By controlling the number of weak ionic hydrogen bonds through ion concentration, a synergistic balance of the hierarchical hydrogen bond system is achieved. This invention addresses the problems of existing cellulose-based materials, such as difficulty in simultaneously achieving high tensile strength and high fracture strain, reliance on energy-intensive nanocellulose preparation processes, poor interfacial compatibility, impaired biocompatibility and degradability, difficulty in large-scale preparation of bulk materials, and low recycling rates.

The invention relates to the technical field of bamboo wood treatment, in particular to a mould-proof process for treating bamboo wood through cooperation of low-temperature freezing and ultrasonic waves. The mould-proof technology comprises the following steps that bamboo wood is sequentially subjected to water immersion treatment and freeze-thaw cycle treatment, and freeze-thawed bamboo wood is obtained; and the freeze-thawed bamboo wood is subjected to ultrasonic treatment under the water bath condition, and the modified bamboo wood is obtained. According to the mildew-proof process, the water-saturated bamboos are sequentially subjected to freeze-thaw cycle treatment and ultrasonic treatment, and the freeze-thaw cycle treatment can enable water permeating pores in the bamboos to be condensed into ice crystals to cause volume expansion, so that a transverse substance transmission channel is effectively established, the permeability is improved, and meanwhile, the macroscopic mechanical integrity of the bamboos is kept. The enhanced dissolution effect of the ultrasonic cavitation effect promotes dissolution of a microbial metabolism substrate and maintains the basic integrity of a cellulose microfibril network at the same time, so that a nutrient matrix required by microbial metabolism is fundamentally eliminated, and long-acting mildew prevention is realized.