Described are flame retardant, porous plastic flame arrestors. The flame retardant, porous plastic flame arrestor is formed by irradiating a flame retardant polymer resin to achieve a fractional melt index, grinding the flame retardant polymer resin into a powder, and sintering the flame retardant polymer resin to form a porous structure. Irradiating the flame retardant polymer resin increases the resin's molecular weight and reduces the resin's melt index through crosslinking.

A molded article of polyolefin-based resin expanded beads having excellent appearance and further suppressed color unevenness is provided.

Polyolefin-based resin expanded beads obtained by expanding polyolefin-based resin particles including one or two or more metal borates selected from zinc borate and magnesium borate, wherein the particles of the metal borate has an arithmetic average particle diameter based on the number of 1 μm or more, and a number rate of the particles of the metal borate having a particle diameter of 5 μm or more is 20% or less. A method for producing polyolefin-based resin expanded beads by releasing expandable polyolefin-based resin particles containing one or two or more metal borates selected from zinc borate and magnesium borate and a physical blowing agent dispersed in an aqueous medium in a closed vessel together with the aqueous medium from the closed vessel to a low pressure region than an inside of the closed vessel to expand the expandable polyolefin-based resin particles, the method comprising: using a metal borate having an arithmetic average particle diameter based on the number of 1 μm or more and a number rate of the particles having a particle diameter of 5 μm or more of 20% or less as the metal borate.

An air-permeable filter material that includes a polymeric aerogel having a polymeric matrix comprising an open-cell structure is disclosed. The air-permeable filter material can be included in a mask, which can be configured to be placed over a user's mouth and/or nose. The mask can include at least one layer of the air-permeable filter material and is positioned such that inhaled and/or exhaled air of the user passes through the filter material.

In the present invention, a multi-stage foam sound-absorbing black body material is provided for the first time. A graphene aerogel is introduced into a commercialized polymer foam skeleton by using a solvent plasticizing and foaming technology, so as to embed ultra-thin graphene drums in the foam skeleton. When sound waves enter the foam black body, a large number of graphene drums generate a severe resonance effect, thereby rapidly achieving attenuation of the sound waves, and combined with the friction loss of the porous structure of the polymer foam on the sound waves, excellent sound-absorbing performance is achieved in a wide frequency range. The present solution is provided on the basis of commercialized foam materials, has a simple method, low costs, and the potential of wide industrial application.

A microporous polyolefin (PO) foamed material is provided, which is prepared from a PO composition through a foaming process, where the PO composition includes a PO and an additive composition, and with the PO composition as 100 parts by mass, the additive composition accounts for 3 to 20 parts by mass; the additive composition includes a functional additive A; the functional additive A has a molecular formula of R—(OCH.sub.2CH.sub.2).sub.xOH, where R is an aralkyl group, a straight alkyl chain, or a branched alkyl chain that has 5 to 60 carbon atoms, and x is 1 to 20; and an absolute value of a solubility parameter difference between the PO and the functional additive A is greater than or equal to 1 (J/cm.sup.3).sup.1/2 and less than or equal to 5 (J/cm.sup.3).sup.1/2 . When the method is used for PO foaming, the foaming efficiency is greatly improved, thereby reducing a production cost.

The present disclosure provides a modified starch composition. The modified starch composition includes starch with a terminal siloxane having 100 parts by weight, water having 30-70 parts by weight, and a polyol having 5-35 parts by weight. The present disclosure also provides a starch composite foam material and method for preparing the same.

A foam and a foaming composition are provided. The foam includes a composite material and a plurality of foam cells, wherein the foam cells are disposed in the composite material. The composite material includes a modified sulfur-containing polymer and a fluorine-containing polymer fiber, wherein a degree of orientation as defined by the ratio I.sub.110/I.sub.200 is from 1.0 to 1.3, wherein I.sub.110 is the X-ray diffraction peak intensity of (110) planes of the modified sulfur-containing polymer and I.sub.200 is the X-ray diffraction peak intensity of (200) planes of the modified sulfur-containing polymer.

High strength biomedical materials and processes for making the same are disclosed. Included in the disclosure are nanoporous hydrophilic solids that can be extruded with a high aspect ratio to make high strength medical catheters and other devices with lubricious and biocompatible surfaces.

An aerogel that includes an open-cell structured polymer matrix is disclosed. The aerogel includes 5 wt. % to 50 wt. % of a polyamic amide polymer, based on the total weight of the aerogel, pores and at least 90% of the pore volume of the aerogel is made up of macropores, a porosity of at least 50%, as measure according to ASTM D4404-10, a density of 0.01 g/cm.sup.3 to 0.5 g/cm.sup.3, and the aerogel is thermally stable to resist browning at 330° C.

Aerogel compositions that include polyamic amides, methods for preparing the aerogel compositions, and articles of manufacture that include or manufactured from the aerogel compositions are described.