A method for forming porous fibers is provided. The fibers are formed from a thermoplastic composition containing a continuous phase, which includes a matrix polymer, and a nanoinclusion additive that is at least partially incompatible with the matrix polymer so that it becomes dispersed within the continuous phase as discrete nano-scale phase domains. The method includes traversing a bundle of the fibers through a multi-stage drawing system that includes at least a first fluidic drawing stage and a second fluidic drawing stage. The first drawing stage employs a first fluidic medium having a first temperature and the second drawing stage employs a second fluidic medium having a second temperature. The first and second temperatures are both lower than the melting temperature of the matrix polymer, and the first temperature is greater than the second temperature.

Ultra-thin nanometer-sealer freestanding polymeric membranes and methods for producing ultra-thin nanometer-scale freestanding recast membranes and ultra-thin nanometer-scale freestanding cross-linked membranes with solid internal backbone are disclosed.

The present invention provides a thermosetting method to form a porous polytetrafluoroethylene membrane, wherein a heat flow in a heat circulating environment is provided to ensure the porous polytetrafluoroethylene membrane is heated uniformly. A thermal heating radiation plat is further used that being heated by the heat flow to generate a far-infrared radiation for providing an enhanced heating effect without extra energy consuming sources. The thermosetting method of porous polytetrafluoroethylene membrane not only maintain a uniformity temperature inside the heating compartment, stabilize the quality of the polytetrafluoroethylene porous membrane, but also make the thermosetting process more efficiently without using extra energy input.

The present invention provides an ultrafiltration membrane comprising a sulfone polymer membrane matrix with pores and an organic polymer sealing layer, wherein the pores are filled with nanoadsorbents. The present invention further provides a method for preparing the ultrafiltration membrane, which includes the following steps: (1) synthesizing nanoadsorbents; (2) preparing the sulfone polymer membrane matrix by immersion-precipitation phase inversion; and (3) immobilizing nanoadsorbents in the pores of the sulfone polymer membrane matrix by reverse filling, then sealing the pores with organic polymers to form a multifunctional ultrafiltration membrane. In the present invention, colloidal gold, polyethylene glycol molecules and Pb(II) ions (and so forth) are utilized as models of viruses, macromolecular organic pollutants, and small molecular pollutants, respectively. It is shown that the multifunctional ultrafiltration membrane allows for removal of multiple pollutants from water and can simultaneously remove multiple pollutants under low pressure.

An organomimetic device includes a microfluidic device that can be used to culture cells in its microfluidic channels. The organomimetic device can be part of dynamic system that can apply mechanical forces to the cells by modulating the microfluidic device and the flow of fluid through the microfluidic channels. The membrane in the organomimetic device can be modulated mechanically via pneumatic means and/or mechanical means. The organomimetic device can be manufactured by the fabrication of individual components separately, for example, as individual layers that can be subsequently laminated together.

One aspect of the present invention relates to a porous membrane having a porous structure, wherein when a fractal dimension is calculated under a plurality of conditions including at least two or more conditions, the fractal dimension being to be calculated from image data obtained by photographing a porous structure on a cut section formed by cutting the porous membrane on a discretionary section in which at least the porous structure is observed, at a discretionary photographing position and a discretionary photographing magnification at which at least the porous structure of the membrane section is observed, all of the fractal dimensions calculated under each of the plurality of conditions are 1.5 or more and 1.9 or less.

The present invention pertains to a process for the manufacture of a grafted fluoropolymer [polymer (Fg)], said process comprising reacting: A) at least one fluoropolymer comprising at least one functional group selected from the group consisting of a hydroxyl group and a carboxylic acid group [polymer (F)], B) at least one polyoxyalkylene (POA) of formula (I): R.sub.B(CH.sub.2O).sub.x(CH.sub.2CHR.sub.AO).sub.n(CH.sub.2O).sub.xR.sub.C, wherein at least one of R.sub.B and R.sub.C is a reactive group comprising at least one heteroatom selected from oxygen and nitrogen different from the hydroxyl group, the remaining, if any, being a [O].sub.zCH.sub.3 alkyl group, wherein z is 0 or 1, R.sub.A is a hydrogen atom or a C.sub.1-C.sub.5 alkyl group, x and x, equal to or different from each other, are independently 0 or 1, and n is an integer comprised between 2 and 1000, preferably between 5 and 200, C) optionally, in the presence of at least one catalyst, and D) optionally, in the presence of at least one organic solvent (S). The present invention also pertains to grafted fluoropolymers obtained from said process and to uses of said grafted fluoropolymers for manufacturing porous membranes.

Disclosed is a method of producing a microporous polymer membrane, comprising: providing a polymer material; melting the polymer material; forming a precursor film by cooling and crystallizing the molten polymer material using an air knife; extending the precursor film; annealing the extended precursor film, primary stretching the annealed precursor film; forming a preliminary membrane by subjecting the primary stretched film to secondary stretching at a high temperature, and forming a microporous polymer membrane by heat setting the preliminary membrane. A microporous polymer membrane produced by the method is also provided.

Ultra-thin nanometer-sealer freestanding polymeric membranes and methods for producing ultra-thin nanometer-scale freestanding recast membranes and ultra-thin nanometer-scale freestanding cross-linked membranes with solid internal backbone are disclosed.

A polyurethane porous membrane is produced by a simple method to be used for at least one of applications of cell culture and cancer cell growth inhibition. The production method of the polyurethane porous membrane to be used for at least one of the applications of cell culture and cancer cell growth inhibition comprises: a first step of forming a layer of a polyurethane material which is uncured, on a substrate; and a second step of supplying water vapor to an exposed surface of the layer of the polyurethane material formed on the substrate, which is away from the substrate, so as to cure the polyurethane material and provide the layer of the polyurethane material with a porous structure having a plurality of irregularities on the exposed surface.