摘要:
Efficient processes have been developed for the cost effective functionalization of polyhedral oligomeric silsesquioxane-silanols (POSS-Silanols) and for the manufacture of polyfunctional polyhedral oligomeric silsesquioxanes. The processes utilize the action of bases or acids on silane coupling agents. The preferred process utilizes base to promote the silylation of POSS-Silanols of the formula [(RSiO1.5)n(R(HO)SiO1.0)m]Σ# with silane coupling agents to form POSS species with functionalized incompletely condensed nanostructures [(RSiO1.5)n(R(YSiR2O)SiO1.0)m]Σ# or functionalized completely condensed nanostructures [(RSiO1.5)n(YSiO1.5)1]Σ#. The process can alternately be conducted with acids. A second process utilizes base to alkylate POSS-Silanols with functionalized alkyl halides. A third related process utilizes base to react with silane coupling agents to form polyfunctional, fully condensed POSS species of formula [(YSiO1.5)n]Σ#. This process can also alternately be conducted under acidic conditions. Each of the processes result in new POSS compositions that can undergo additional desirable chemical reactions or which are directly suitable for polymerization or grafting into polymeric materials. POSS frameworks containing silanol and other reactive functionalities suitable for polymerizations have previously been described as valuable co-monomers in polymerizations and as feed-stocks for the preparation of a diverse number of chemical agents that are useful in polymeric materials in biological applications, and for the modification of surfaces.
摘要:
Nanostructured chemicals such as polyhedral oligomeric silsesquioxanes, polyhedral oligomeric silicates, and polyhedral oligomeric metallasesquioxanes are attached to living and nonliving systems as biomaterials to provide a nanoscopic topology that favors biomimetic function and cellular modulation. The resulting surface is nanoscopically thin, nanoscopically dispersed, provides systematic chemistry, surface area, surface volume, surface topology, and is essentially free of impurities, and has controllable properties through selection of composition, R groups, nanostructure size and topology. Highly shape specific and chemically tailorable nanostructured molecules are sized to biological material dimensions and are compatible with all sterilization methods.
摘要:
Nanoreinforced coatings with improved hydrophobicity, thermal stability, hardness, and durability have been developed from polyhedral oligomeric silsesquioxane (POSS) reagents and resins. The nanoscopic dimensions and hybrid (organic/inorganic) composition of POSS reagents are particularly useful for coating fillers derived from minerals, metals, glasses, and polymeric materials.
摘要:
Nanostructured chemicals such as polyhedral oligomeric silsesquioxanes, polyhedral oligomeric silicates, and polyhedral oligomeric metallasesquioxanes are attached to living and nonliving systems as biomaterials to provide a nanoscopic topology that favors biomimetic function and cellular modulation. The resulting surface is nanoscopically thin, nanoscopically dispersed, provides systematic chemistry, surface area, surface volume, surface topology, and is essentially free of impurities, and has controllable properties through selection of composition, R groups, nanostructure size and topology. Highly shape specific and chemically tailorable nanostructured molecules are sized to biological material dimensions and are compatible with all sterilization methods.
摘要:
The use of nanostructured chemicals based on polyhedral oligomeric silsesquioxanes (POSS) and polyhedral oligomeric silicates (POS) are used to control porosity in organic and inorganic media. The precisely defined nanoscopic dimensions of this class of chemicals enables porosity to be both created (increased) or reduced (decreased) as desired. The thermal and chemical stability of the POSS/POS nanostructures and the ability of these nano-building blocks to be selectively placed or rationally assembled with both inorganic and organic material mediums allow tailoring of porosity.
摘要:
A method of using fluorinated-nanostructured POSS chemicals as alloying agents for the reinforcement of polymer microstructures, including polymer coils, domains, chains, and segments, at the molecular level. Because of their tailorable compatibility with nonfluorinated polymers, nanostructured chemicals can be readily and selectively incorporated into polymers by direct blending processes. The incorporation of a nanostructured chemical into a polymer favorably impacts a multitude of polymer physical properties. Properties most favorably improved are surface properties, such as lubricity, contact angle, water repellency, deicing, surface tension, and abrasion resistance. Improved surface properties may be useful for applications such as anti-icing surfaces, non-wetting surfaces, low friction surfaces, self cleaning. Other properties improved include time dependent mechanical and thermal properties such as heat distortion, creep, compression set, shrinkage, modulus, hardness and biological compatibility. In addition to mechanical properties, other physical properties are favorably improved, including lower thermal conductivity, dielectric properties, fire resistance, gas permeability and separation. These improved properties may be useful in a number of applications, including space-survivable materials and seals, gaskets, cosmetics, and personal care.
摘要:
A method of using fluorinated-nanostructured POSS chemicals as alloying agents for the reinforcement of polymer microstructures, including polymer coils, domains, chains, and segments, at the molecular level. Because of their tailorable compatibility with nonfluorinated polymers, nanostructured chemicals can be readily and selectively incorporated into polymers by direct blending processes. The incorporation of a nanostructured chemical into a polymer favorably impacts a multitude of polymer physical properties. Properties most favorably improved are surface properties, such as lubricity, contact angle, water repellency, deicing, surface tension, and abrasion resistance. Improved surface properties may be useful for applications such as anti-icing surfaces, non-wetting surfaces, low friction surfaces, self cleaning. Other properties improved include time dependent mechanical and thermal properties such as heat distortion, creep, compression set, shrinkage, modulus, hardness and biological compatibility. In addition to mechanical properties, other physical properties are favorably improved, including lower thermal conductivity, dielectric properties, fire resistance, gas permeability and separation. These improved properties may be useful in a number of applications, including space-survivable materials and seals, gaskets, cosmetics, and personal care.
摘要:
A method of using olefin containing nanostructured chemicals and silanol containing nanostructured chemicals as high temperature resins is described. Vinyl containing nanostructured chemicals are particularity effective in thermosets as they control the motions of polymer chains, and segments, at the molecular level. Silanol containing nanostructured chemicals are particularity effective in thermosets containing polar groups as the silanol can enhance the reactivity of these groups. Because of their tailorable compatibility with fluorinated polymers, nanostructured chemicals can be readily and selectively incorporated into polymers by direct blending and polymerization processes. The incorporation of a nanostructured chemical into a polymer favorably impacts a multitude of polymer physical properties. Properties most favorably improved are heat distortion and flammability characteristics, permeability, optical properties, texture, feel and durability. Other properties improved include time dependent mechanical and thermal properties such as creep, compression set, shrinkage, modulus, and hardness. In addition to mechanical properties, other physical properties are favorably improved, including lower thermal conductivity, and gas oxygen permeability. These improved properties may be useful in a number of applications, including composite materials, foams, cosmetics, and durable coatings.
摘要:
Three processes for the manufacture of polyhedral oligomeric silsesquioxanes (POSS) which utilize the action of bases that are capable of either attacking silicon or any compound that can react with a protic solvent (e.g. ROH, H2O etc.) and generate hydroxide [OH]−, alkoxide [RO]−′, etc. The first process utilizes such bases to effectively redistribute the silicon-oxygen frameworks in polymeric silsesquioxanes [RSiO1.5]28 where ∞=1-1,000,000 or higher into POSS nanostructures of formulas [(RSiO1.5)nΣ#, homoleptic, [(RXSiO1.5)n]Σ#, functionalized homoleptic, [(RSiO1.5)m(R′SiO1.5)n]Σ#, heteroleptic, and {(RSiO1.5)m(RXSiO1.0)n}Σ#, functionalized heteroleptic nanostructures. The second process utilizes base to aid in the formation of POSS nanostructures of formulas [(RSiO1.5)n]Σ# homoleptic and [(RSiO1.5)m(R′SiO1.5)n]Σ# heteroleptic and [(RSiO1.5)m(RXSiO1.0)n]Σ# functionalized heteroleptic nanostructures from silanes RSiX3 and linear or cyclic silsesquioxanes of the formula RX2Si—(OSiRX)m—OSiRX2 where m=0-10, X=OH, Cl, Br, I, alkoxide OR, acetate OOCR, peroxide OOR, amine NR2, isocyanate NCO, and R. The third process utilizes base to selectively ring-open the silicon-oxygen-silicon (Si—O—Si) bonds in POSS structures to form POSS species with incompletely condensed nanostructures. These processes also afford stereochemical control over X. The three processes result in new POSS species that can undergo additional chemical manipulations to ultimately be converted into POSS-species suitable for polymerization, grafting, or other desirable chemical reactions.
摘要:
Method is provided for selectively opening rings of polyhedral oligomeric silsesquioxane (POSS) compounds to from functionalized derivatives thereof or new POSS species. Per the inventive method, the POSS compound is reacted with an acid to selectively cleave bonds in the POSS rings to add functionalities thereto for grafting, polymerization or catalysis, to thus form new familes of POSS derived compounds. Also provided are the new compounds so formed. Method is also provided for expanding rings of POSS compounds. Per the inventive method, a POSS compound is reacted with silane reagents to obtain an expanded POSS framework with added Si ring substituends to form new families of POSS compounds. Also provided are the new compounds so formed.