The present disclosure provides for porous polymer materials that include an ordered array of voids separated by a polymer framework. The porous polymer material can have a recovery state where the voids are in an uncollapsed state and iridescent color, and a deformed state having voids in a collapsed state that is non-iridescent or substantially transparent. The materials can have regions of both states simultaneously. Also described are methods for fabricating a polymer material as above, as well as chromogenic sensors including the polymer material. The sensors can have hidden anti-counterfeiting patterns, hydrophobic/oleophobic properties, and chromogenic transformation can be triggered by various stimuli such as solid target compounds, light energy, and more.

The present disclosure provides for porous polymer materials that include an ordered array of voids separated by a polymer framework. The porous polymer material can have a recovery state where the voids are in an uncollapsed state and iridescent color, and a deformed state having voids in a collapsed state that is non-iridescent or substantially transparent. The materials can have regions of both states simultaneously. Also described are methods for fabricating a polymer material as above, as well as chromogenic sensors including the polymer material. The sensors can have hidden anti-counterfeiting patterns, hydrophobic/oleophobic properties, and chromogenic transformation can be triggered by various stimuli such as solid target compounds, light energy, and more.

Provided herein are methods utilizing microfluidics for the oxygen-controlled generation of microparticles and hydrogels having controlled microparticle sizes and size distributions and products from provided methods. The included methods provide the generation of microparticles by polymerizing an aqueous solution dispersed in a non-aqueous continuous phase in an oxygen-controlled environment. The process allows for control of size of the size of the aqueous droplets and, thus, control of the size of the generated microparticles which may be used in biological applications.

Provided herein are methods utilizing microfluidics for the oxygen-controlled generation of microparticles and hydrogels having controlled microparticle sizes and size distributions and products from provided methods. The included methods provide the generation of microparticles by polymerizing an aqueous solution dispersed in a non-aqueous continuous phase in an oxygen-controlled environment. The process allows for control of size of the size of the aqueous droplets and, thus, control of the size of the generated microparticles which may be used in biological applications.

A method disclosed herein includes forming a polishing pad configured for a chemical-mechanical polishing (CMP) process and polishing a workpiece using the polishing pad and a CMP slurry. Forming the polishing pad includes forming an interpenetrating polymer network having a first phase and a second phase embedded in the first phase, removing the second phase from the interpenetrating polymer network, thereby forming a porous top pad that includes a network of pores embedded in the first phase, and adhering the porous top pad to a sub pad, thereby forming the polishing pad. The second phase is different from the first phase in composition, and the interpenetrating polymer network has a substantially periodic pattern. Surface roughness of the porous top pad is consistent during the polishing of the workpiece.

A method disclosed herein includes forming a polishing pad configured for a chemical-mechanical polishing (CMP) process and polishing a workpiece using the polishing pad and a CMP slurry. Forming the polishing pad includes forming an interpenetrating polymer network having a first phase and a second phase embedded in the first phase, removing the second phase from the interpenetrating polymer network, thereby forming a porous top pad that includes a network of pores embedded in the first phase, and adhering the porous top pad to a sub pad, thereby forming the polishing pad. The second phase is different from the first phase in composition, and the interpenetrating polymer network has a substantially periodic pattern. Surface roughness of the porous top pad is consistent during the polishing of the workpiece.

Multiple processes for preparing porous articles are described. The porous articles can be in a wide array of shapes and configurations. The methods include providing a soluble material in particulate form and forming a packed region from the material. The methods also include contacting a flowable polymeric material with the packed region such that the polymeric material is disposed in voids in the packed region. Also described are systems for performing the various processes.

Multiple processes for preparing porous articles are described. The porous articles can be in a wide array of shapes and configurations. The methods include providing a soluble material in particulate form and forming a packed region from the material. The methods also include contacting a flowable polymeric material with the packed region such that the polymeric material is disposed in voids in the packed region. Also described are systems for performing the various processes.

Highly transparent (up to 92% light transmittance) wood composites have been developed. The process of fabricating the transparent wood composites includes lignin removal followed by index-matching polymer infiltration resulted in fabrication of the transparent wood composites with preserved naturally aligned nanoscale fibers. The thickness of the transparent wood composite can be tailored by controlling the thickness of the initial wood substrate. The optical transmittance can be tailored by selecting infiltrating polymers with different refractive indices. The transparent wood composites have a range of applications in biodegradable electronics, optoelectronics, as well as structural and energy efficient building materials. By coating the transparent wood composite layer on the surface of GaAs thin film solar cell, an 18% enhancement in the overall energy conversion efficiency has been attained.

Highly transparent (up to 92% light transmittance) wood composites have been developed. The process of fabricating the transparent wood composites includes lignin removal followed by index-matching polymer infiltration resulted in fabrication of the transparent wood composites with preserved naturally aligned nanoscale fibers. The thickness of the transparent wood composite can be tailored by controlling the thickness of the initial wood substrate. The optical transmittance can be tailored by selecting infiltrating polymers with different refractive indices. The transparent wood composites have a range of applications in biodegradable electronics, optoelectronics, as well as structural and energy efficient building materials. By coating the transparent wood composite layer on the surface of GaAs thin film solar cell, an 18% enhancement in the overall energy conversion efficiency has been attained.