A polymer matrix composite includes a porous polymeric network structure; and a plurality of acoustically active particles distributed within the polymeric network structure. The weight fraction of acoustically active particles is between 0.80 and 0.99, based on the total weight of the polymer matrix composite. The polymer matrix composite has an air flow resistance of less than 100 seconds/50 mL/500 μm.

When a polymer gel has excellent mechanical strength and an ability to maintain surface wetness for a longer time, the polymer gel may be very widely applied to a variety of fields. The present disclosure provides example embodiments of a polymer gel having excellent mechanical strength and an ability to maintain surface wetness for a longer time. Further, the present disclosure provides example embodiments of a method of preparing the polymer gel.

A porous polybenzimidazole (PBI) particulate resin is disclosed. This resin is easily dissolved at ambient temperatures and pressures. The resin is made by: dissolving a virgin PBI resin in a highly polar solvent; precipitating the dissolved PBI in a bath; and drying the precipitated PBI, the dried precipitated PBI being porous. The porous PBI resin may be dissolved by: mixing a porous PBI resin with a highly polar solvent at ambient temperatures and pressures to form a solution.

An emulsifier-free process for the preparation of water expandable polymer beads, including: a) providing an emulsifier-free starting composition comprising styrene, b) prepolymerizing the starting composition to obtain a prepolymer composition, c) mixing an aqueous blowing agent with the prepolymer composition at an elevated temperature to obtain an inverse emulsion of water droplets in the prepolymer composition, wherein the aqueous blowing agent comprises water and a water soluble initiator dissolved in the water and the water droplets comprise spheres of a styrene polymer, wherein the water soluble initiator partly decomposes due to the elevated temperature leading to the formation of the inverse emulsion of water droplets in the prepolymer composition, d) suspending the inverse emulsion in an aqueous medium to yield an aqueous suspension of suspended droplets and e) polymerizing monomers in the droplets of the suspension obtained by step d) to obtain the water expandable polymer beads.

The present invention relates to a porous silicone body having communicating pores and a three-dimensional network silicone skeleton that forms the pores, wherein the silicone skeleton is formed by polymerization of a bifunctional alkoxysilane and a trifunctional alkoxysilane, and the proportion of unreacted parts in the silicone skeleton is 10 mol % or less. The porous silicone body of the present invention has high flexibility and high heat resistance, and further has excellent recoverability of heat-resistant cushioning properties.

This invention relates to compositions comprising 1,2-dichloro-1,2-difluoroethylene (i.e., CFO-1112) and an additional component. The compositions described herein may be useful, for example, in foam blowing applications.

The use of polyamine- and/or polyalkanolamine-based carboxylic acid derivatives as additives in aqueous polymer dispersions for production of porous polymer coatings, preferably for production of porous polyurethane coatings, is described.

An expanded polypropylene resin particle is obtained from a base material resin having a melting point of 140° C. to 150° C., wherein the base material resin includes a polypropylene resin A including 3 weight % to 15 weight % of 1-butene and having a melting point of 130° C. to 140° C.; and a polypropylene resin B having a melting point of 145° C. to 165° C., and wherein the expanded polypropylene resin particle has an average cell diameter of 100 μm to 340 μm.

4-methyl-1-pentene based resin foam containing a 4-methyl-1-pentene based resin, and having an expansion ratio of 3 times or more is prepared. When measured in a decalin solvent at 135° C., an intrinsic viscosity [η] of the 4-methyl-1-pentene based resin may be 0.5 to 5 dl/g. The 4-methyl-1-pentene based resin may have a glass transition temperature of 0° C. to 80° C. The 4-methyl-1-pentene based resin may have a melting point. The 4-methyl-1-pentene based resin may be a 4-methyl-1-pentene/C.sub.2-20α-olefin copolymer (in particular, 4-methyl-1-pentene/C.sub.2-4α-olefin copolymer). The expansion ratio of the 4-methyl-1-pentene based resin foam may be 10 times or greater.

A shoe sole member formed by a foam includes cells having a certain size and being excellent in transparency in order to provide a shoe sole member being lightweight and excellent cushioning properties while having transparency.