Liquid-free, polymeric reinforcement of nanoscale assemblies

Abstract

Provided herein is a nanoscale material assembly made up of a plurality of nanoscale structures with a crosslinked polymer thermally deposited on the structures. Also disclosed are methods for preparing the nanoscale material assembly with a deposited crosslinked polymer. Further disclosed are various conditions and materials that when used in the preparation of the nanoscale material assemblies further enhance their mechanical properties. In some embodiments, the nanoscale material assemblies can be either nanoscale yarn assemblies or nanoscale sheet assemblies.

1 . A method for fabricating a nanoscale material assembly, comprising:
 depositing a thermally self-crosslinkable polymer by a vapor-phase method on a nanoscale material substrate comprising a plurality of carbon nanotubes arranged as yarns or free-standing sheets;   inducing crosslinking of the thermally self-crosslinkable polymer deposited on the nanoscale material substrate by thermalizing the thermally self-crosslinkable polymer to obtain a nanoscale material assembly comprising a crosslinked polymer.   
     
     
         2 . The method of  claim 1 , wherein the deposition comprises:
 placing the nanoscale material substrate into a vacuum chamber reactor; and   depositing a thermally self-crosslinkable polymer to the nanoscale material substrate comprising the plurality of nanoscale structures under polymerization conditions, wherein the thermally self-crosslinkable polymer is produced in situ from a vapor or gas phase precursor reacting with the reaction initiator upon surface adsorption.   
     
     
         3 . The method of  claim 1 , wherein the inducing comprises:
 thermalizing the thermally self-crosslinkable polymer deposited on the nanoscale material substrate in an environment comprising a gaseous bleed.   
     
     
         4 . The method of  claim 1 , wherein the nanoscale material assembly comprises a metal mesh or another material that can be placed into a reactor and is stable at initiated chemical vapor deposition conditions used to deposit the polymer. 
     
     
         5 . The method of  claim 1 , wherein the thermalization takes place under ultraviolet light or in an initiated chemical vapor deposition reactor. 
     
     
         6 . The method of  claim 1 , wherein the thermally self-crosslinkable polymer is poly-glycidyl methacrylate (PGMA). 
     
     
         7 . The method of  claim 1 , wherein the thermally self-crosslinkable polymer is any one or a combination of acrylates or methacrylate based polymers capable of being coated onto a nanoscale structure via initiated chemical vapor deposition. 
     
     
         8 . The method of  claim 1 , wherein the deposition conditions are between 100° to 350° C. for the filament, 10° and 40° Celsius for the assembly and between 0.001 torr and 100 torr for the reactor. 
     
     
         9 . The method of  claim 1 , wherein the thermalizing takes place for anywhere from 15 minutes to 120 minutes and in a temperature range from 80° Celsius to 200° Celsius. 
     
     
         10 . The method of  claim 1 , wherein, prior to deposition, a mist of a solvent is used to condense the carbon nanotube yarn assemblies or sheet assemblies in the lateral dimension. 
     
     
         11 . The method of  claim 2 , wherein the precursor comprises glycidyl methacrylate and the reaction initiator comprises tert-butylperoxide (TBPO). 
     
     
         12 . The method of  claim 3 , wherein the gaseous bleed is an inert gas. 
     
     
         13 . The method of  claim 10 , wherein the solvent is an alcohol or acetone. 
     
     
         14 . The method of  claim 1 , wherein the method does not comprise depositing the thermally self-crosslinkable polymer or inducing crosslinking of the thermally self-crosslinkable polymer in a liquid phase. 
     
     
         15 - 21 . (canceled) 
     
     
         22 . The method of  claim 1 , wherein thermalizing the thermally self-crosslinkable polymer comprises thermalizing the thermally self-crosslinkable polymer at a temperature greater than 100 degrees Celsius. 
     
     
         23 . The method of  claim 1 , comprising forming mechanical reinforcing of a plurality of inter-nanotube entanglement points of the plurality of carbon nanotubes. 
     
     
         24 . The method of  claim 1 , wherein an amount of the thermally self-crosslinkable polymer is equivalent to less than 200 nanometers (nm) on a flat substrate. 
     
     
         25 . The method of  claim 1 , comprising applying a solvent to the plurality of carbon nanotubes prior to deposition of the thermally self-crosslinkable polymer. 
     
     
         26 . The method of  claim 25 , comprising applying the solvent to decrease inter-nanotube distances of the plurality of carbon nanotubes. 
     
     
         27 . The method of  claim 1 , wherein the plurality of carbon nanotubes comprise carbon nanotube spinnable forests.