Tianjin Polytechnic University

Shulin An

Changfa Xiao

Qinglin Huang

Xiaoyu Hu

Mingxing Chen

Chun Wang

Jingjing Yan

Hailiang Liu

Zhongqing Miao

Haixian Liang

Naiku Xu

Yan Feng

Guangxia Jia

A homogeneous fiber reinforced PVDF hollow fiber membrane and a preparation method thereof are provided. The membrane includes a hollow tubular reinforcement made of PVDF fibers and a polymer separation layer made of PVDF casting solution; wherein the polymer separation layer casting solution comprises 4-25% PVDF resin, 5-20% pore-forming agent, 0-3% inorganic particles and 52-91% solvent according to mass fraction. The preparation method includes steps of: (1) preparing a hollow tubular reinforcement made of PVDF fibers; (2) preparing a PVDF polymer separation layer casting solution; and (3) obtaining the homogeneous fiber reinforced PVDF hollow fiber membrane.

Homogeneous fiber reinforced PVDF hollow fiber membrane and preparation method thereof

A method for preparing an aromatic polyamide porous hollow fiber membrane firstly premixes PPTA resin, solvent, composite pore-forming agents and inorganic particles in a stirring vessel to form casting solution, secondly injects the casting solution into a double-screw extruder to be fully dissolved under the effect of shear force and enters a spinneret via a metering pump. The PPTA hollow fiber membranes are prepared by the dry-wet spinning method, which solves the problems that hard pore-forming and low porosity in the preparation process of PPTA porous membrane. Utilization of the double-screw extruder is capable of greatly shortening the dissolved time and the deaeration time. Meanwhile the increase of PPTA in casting solution also improves mechanical properties of the PPTA membrane. The addition of the inorganic particles improves mechanical toughness and enhance pure water flux, hydrophilia and rejection rate.

Method for preparing aromatic polyamide porous hollow fiber membrane

A preparation method of a perfluorinated polymer hollow fiber membrane comprises: evenly mixing a first mixture that is mixed by a perfluorinated polymer, PS, a polymer additive, and a composite pore-forming agent; evenly mixing a second mixture that is mixed by the first mixture and an organic liquid; under 300&#xb0; C.-350&#xb0; C., processing the second mixture with a melt to spin by a twin-screw extruder; extruding a hollow fiber by a hollow fiber spinneret; dipping the hollow fiber membrane into deionized water for 48 hours; putting the hollow fiber membrane aired into a concentrated sulfuric acid to process with a sulfonation; washing the hollow fiber membrane by deionized water; and drying the hollow fiber membrane; in such a manner that the hydrophilic perfluorinated polymer hollow fiber membrane is obtained.

Preparation method of perfluorinated polymer hollow fiber membrane

A composition for preparation of a hollow fiber porous membrane including 40-60 wt. % a polymer matrix, 20-30 wt. % an organic mixed solution, and 20-40 wt. % a water-soluble substance. The polymer matrix is a polymer capable of dissolving in an organic solvent and melt processing. The organic mixed solution is a mixture comprising 60-90 wt. % a first liquid soluble to the polymer matrix and 10-40 wt. % a second liquid insoluble to the polymer matrix. The water-soluble substance is a water-soluble polymer, a low molecular weight water-soluble particle, or a mixture thereof. A method for producing the hollow fiber porous membrane using the composition including a) preparing the organic mixed solution, b) mixing the components of the composition, c) applying melt spinning, d) drawing, and e) washing. The hollow fiber membrane has high strength, large flux, and low cost.

Composition for preparation of hollow fiber porous membrane and preparation method using the same

A method of preparing oil-absorbing fibers by: a) fully dissolving a dispersant and a deionized water in a reaction vessel, adding a methacrylate monomer and an initiator to a reactor and stirring to form a homogenous solution, transferring the homogenous solution into the reaction vessel, charging nitrogen gas, stirring, raising temperature to 70-80&#xb0; C., allowing to react for 2-6 hours, raising temperature to 90-100&#xb0; C., allowing to react for 2-4 hours, collecting a resultant product, washing, drying, and obtaining a white resin; b) drying the white resin, mixing with a swelling agent, and sealing the mixture at room temperature for 48-96 hours to yield a homogenous gel; c) grinding the gel completely, spinning by a plunger spinner, and coagulating with a coagulation bath to yield an as-spun oil-absorbing fiber; and d) drawing the as-spun oil-absorbing fiber with a draw ratio of 2-6 to yield oil-absorbing fibers.

Growing community of inventors

Tianjin, China

Shulin An