Methods of making permeable aerogels (100) can include providing a sol mixture (110) comprising an organic scaffold, an inorganic aerogel precursor, and a first solvent. The organic scaffold can be insoluble in the first solvent. The sol mixture can react to form a gel (120) such that an interconnected channel network is formed which is at least partially defined by the organic scaffold. The first solvent in the gel can be exchanged (130) with a second solvent. The second solvent can dissolve the organic scaffold to expose the interconnected channel network. The gel can be dried (140) to form the permeable aerogel.

The present invention provides multi-layer articles for use as a rail tie footings comprising, as the tie, an elongate rigid body having a substantially planar surface, and on the substantially planar surface comprising a a microcellular foam elastomeric pad, for example, of a substantially organic solvent free polyurethane, wherein the substantially planar surface has a peripheral landing on which there is no elastomeric pad and the elastomeric pad has a bulk density (ASTM D3676) of from 600 to 2000 Kg/m3 (0.6 to 2.0 g/cm3). In addition, the present invention provides molding methods wherein the microcellular foam elastomeric pad is molded directly on the rail tie to form a durable footing, wherein the rail tie forms the bottom boundary of a molding chamber during molding and molding comprises forming the top and side boundaries of the molding chamber by inflating an annular pneumatic seal, positioning the seal on the substantially planar surface of the elongate rigid body and keeping the microcellular foam forming materials under pressure during molding.

This disclosure provides a fluorine-containing mixture and a fluorine-containing super-oleophobic microporous membrane using the fluorine-containing mixture as a raw material, as well as preparation methods and applications for the fluorine-containing mixture and the fluorine-containing super-oleophobic microporous membrane. The fluorine-containing mixture of the present disclosure comprises, by weight percentage, the following components: Component A: 50%˜90%; Component B: 3%˜25%; Component C: 0%˜35%; Component D: 0%˜3%; wherein Component A comprises high molecular weight polytetrafluoroethylene homopolymer or copolymer dispersion resin; Component B comprises one or more fluorine-containing alkyl acrylate monomers; Component C comprises one or more fluorine-free acrylates; Component D comprises high temperature free radical initiator. There's no need to add inflammable or explosive lubricating oil, making the process highly safe; and the obtained fluorine-containing super-oleophobic microporous membrane has high waterproof, air-permeable, oil-resistant and washable performance, in line with the needs of a new generation of waterproof and air-permeable protective clothing.

Provided is a microporous film which has a surface A and a surface B opposite to the surface A. In one embodiment, the microporous film has a ratio (F.sub.B/F.sub.A) of a dynamic friction coefficient F.sub.B of the surface B to a dynamic friction coefficient F.sub.A of the surface A of 1.2 to 20. In another embodiment, the microporous film is a single layer having a thickness of 3-18 μm, a number N.sub.A of pores on the surface A is 10-100/μm.sup.2, a number N.sub.B of pores on the surface B is 20-200/μm.sup.2, and N.sub.A/N.sub.B is 0.2-0.96. In addition, a total area S.sub.A of pores on the surface A is 0.02-0.5 μm.sup.2/μm.sup.2, a total area S.sub.B of pores on the surface B is 0.01-0.3 μm.sup.2/μm.sup.2, and S.sub.A/S.sub.B is 1.1-10. Furthermore, in another embodiment, a number W.sub.B of protrusion-like bodies on the surface B is 0.2-1000/100 μm.sup.2.

A composite structure includes a foam core formed from a first polymer and between about 0.5 wt. % and about 2.5 wt. % graphene. The foam core has an average pore size between about 25 μm and about 75 μm, and a cell density between about 4×10.sup.6 cells/mm.sup.2 and about 6×10.sup.6 cells/mm.sup.2. Also, an overmolded skin formed from a second polymer and between about 0.25 wt. % and about 5.0 wt. % graphene is disposed on the foam core. A method of manufacturing a composite structure includes injection molding a foam core from a first polymer containing between about 0.25 wt. % and about 5.0 wt. % graphene, and injection molding an overmolded skin from a second polymer containing graphene between about 0.25 wt. % and about 5.0 wt. % graphene.

A method is provided for making a microcellular shoe stiffener has first and second adhesive layers coextruded on opposite first and second surfaces of a stiffener core. The stiffener core may include a recycled polymeric material. Nitrogen in a supercritical fluid state is introduced into the extruder for the stiffener core to produce a closed cell foam with a gaseous component. The gas reduces the weight and cost of the stiffener without significantly reducing stiffness and resiliency.

A process for injection molded microcellular foaming various flexible foam compositions from biodegradable and industrially compostable bio-derived thermoplastic resins for use in, for example, footwear components, seating components, protective gear components, and watersport accessories wherein a process of manufacturing includes the steps of: producing a suitable thermoplastic biopolymer or biopolymer blend; injection molding the thermoplastic biopolymer or biopolymer blend into a suitable mold shape with inert nitrogen gas; controlling the polymer melt, pressure, temperature, and time such that a desirable flexible foam is formed; and utilizing gas counterpressure in the injection molding process to ensure the optimal foam structure with the least amount of cosmetic defects and little to no plastic skin on the outside of the foamed structure.

A method for preparing a thermoplastic polyurethane elastomer material with micro air holes is provided. The method comprises the following steps: (1) is feeding liquid raw materials such as diisocyanate molecules and solid additives into a double-screw reactor to trigger a polymerization type chain extension reaction and then obtain a macromolecular weight hot melt. (2) is pushing the macromolecular weight hot melt into a mixing extruder and allowing the reaction to continue to obtain a macromolecular thermoplastic polyurethane melt. (3) is continuously adding the obtained macromolecular thermoplastic polyurethane melt together with polymer particles into a foaming extruder, and extruding the high-pressure hot melt from a mold head into an underwater granulation chamber. (4) is delivering the particles obtained after granulation into a separator by process water via a multi-stage pressure-release process water pipeline, separating, screening and drying the required particles to obtain the target product.

The present disclosure provides device having a reaction vessel with one or more permeable membranes disposed therein that separate the reaction vessel into at least a first portion and a second portion. The one or more membranes permit first reactants from a first solution in the first portion or reactants from a second solution in the second portion to seep or percolate to a reaction zone proximate a surface of the one or more membranes. A reaction of the first and second reactants forms a two-dimensional polymer film material. A roller located inside of the reaction vessel draws the two-dimensional polymer film material reaction out of the reaction zone.

The present disclosure is directed to a physically crosslinked, closed cell continuous multilayer foam structure comprising at least one foam polypropylene/polyethylene layer with a TPU cap layer. The multilayer foam structure can be obtained by coextruding a multilayer structure comprising at least one foam composition layer with at least one cap composition layer, irradiating the coextruded structure with ionizing radiation, and continuously foaming the irradiated structure.