Shaped gel articles that are formed within a mold cavity and that retain the size and shape of the mold cavity upon removal from the mold cavity, sintered articles prepared from the shaped gel articles, and methods of making the sintered articles are provided. The shaped gel articles are formed from a casting sol that contains colloidal silica particles that are treated with a surface modification composition that includes a silane surface modification agent having a radically polymerizable group. The sintered article has a shape identical to the mold cavity (except in regions where the mold cavity was overfilled) and to the shaped gel article but reduced in size proportional to the amount of isotropic shrinkage.

Various embodiments disclosed relate to pore inducers and porous abrasive forms made using the same. In various embodiments, the present invention provides a method of forming a porous abrasive form including heating an abrasive composition including pore inducers to form the porous abrasive form. During the heating the pore inducers in the porous abrasive form reduce in volume to form induced pores in the porous abrasive form.

Methods of forming nanoporous materials are described herein that include forming a polymer network with a chemically removable portion. The chemically removable portion may be polycarbonate polymer that is removable on application of heat or exposure to a base, or a polyhexahydrotriazine (PHT) or polyhemiaminal (PHA) polymer that is removable on exposure to an acid. The method generally includes forming a reaction mixture comprising a formaldehyde, a solvent, a primary aromatic diamine, and a diamine having a primary amino group and a secondary amino group, the secondary amino group having a base-reactive substituent, and heating the reaction mixture to a temperature of between about 50 deg C. and about 150 deg C. to form a polymer. Removing any portion of the polymer results in formation of nanoscopic pores as polymer chains are decomposed, leaving pores in the polymer matrix.

A ceramic resin is provided, along with its methods of formation and use. The ceramic resin may include a crosslinkable precursor, a photoinitiator, ceramic particles, and pore forming particles. The ceramic resin may be utilized to form a ceramic casting element, such as via a method that includes forming a layer of the ceramic resin; applying light onto the ceramic resin such that the photoinitiator initiates polymerization of the crosslinkable precursor to form a crosslinked polymeric matrix setting the ceramic particles and the pore forming particles; and thereafter, heating the crosslinked polymeric matrix to a first temperature to burn out the pore forming particles.

A ceramic resin is provided, along with its methods of formation and use. The ceramic resin may include a crosslinkable precursor, a photoinitiator, ceramic particles, and pore forming particles. The ceramic resin may be utilized to form a ceramic casting element, such as via a method that includes forming a layer of the ceramic resin; applying light onto the ceramic resin such that the photoinitiator initiates polymerization of the crosslinkable precursor to form a crosslinked polymeric matrix setting the ceramic particles and the pore forming particles; and thereafter, heating the crosslinked polymeric matrix to a first temperature to burn out the pore forming particles.

The disclosure is related to compositions having water permeability greater than about 20 g/(hr*m.sup.2) that includes one or more elastomers and one or more agents and methods of preparing the same. The compositions are suitable for use in acoustical devices such as earpieces, e.g., in-ear earpieces.

A porous layer is described. The porous layer comprises a solidified sol-gel inorganic material having a distribution of nanometric voids, wherein at least some of nanometric voids are at least partially coated internally by carbon or a hydrophobic substance containing carbon.

A product of additive manufacturing with a silicone-based ink includes a plurality of continuous filaments comprised of a siloxane matrix, wherein the continuous filaments are arranged in a geometric pattern, a plurality of inter-filament pores defined by the geometric pattern of the continuous filaments, and a plurality of intra-filament pores having an average diameter in a range of greater than 1 micron to less than 50 microns.

The present invention provides a 3D porous structure of parylene including a poly-p-xylylenes structure having a plurality of pores. The poly-p-xylylenes structure has a porosity. According to an embodiment of the present invention, the size of the porous structure is between 20 nm and 5 cm. According to an embodiment of the present invention, the porosity is between 55% and 85%. According to an embodiment of the present invention, the porous structure further includes a plurality of target molecules. According to an embodiment of the present invention, the pores of the poly-p-xylylenes structure include pore sizes of different sizes. The pore sizes are varying in a gradient. According to an embodiment of the present invention, the porous structure is formed integrally.

Methods of forming nanoporous materials are described herein that include forming a polymer network with a chemically removable portion. The chemically removable portion may be polycarbonate polymer that is removable on application of heat or exposure to a base, or a polyhexahydrotriazine (PHT) or polyhemiaminal (PHA) polymer that is removable on exposure to an acid. The method generally includes forming a reaction mixture comprising a formaldehyde, a solvent, a primary aromatic diamine, and a diamine having a primary amino group and a secondary amino group, the secondary amino group having a base-reactive substituent, and heating the reaction mixture to a temperature of between about 50 deg C. and about 150 deg C. to form a polymer. Removing any portion of the polymer results in formation of nanoscopic pores as polymer chains are decomposed, leaving pores in the polymer matrix.