Patent Publication Number: US-2019169379-A1

Title: System that utilizes carbon nanomaterial in polymer matrix with specific features of surface tube and surrounding polymeric interactions for improved aggregate stability

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention relates generally to carbon nanotube systems, and more specifically, to a system with aggregate stability of carbon nanotube polymer matrix with specific features of surface tube and surrounding polymeric interactions. 
     2. Description of Related Art 
     Carbon nanotube systems are well known in the art and are recognized as material with great stiffness and strength, as well as other superior mechanical properties. Carbon nanotubes are currently used in a wide range of industries and include uses such as energy storage, automotive parts, boat hulls, sporting goods, water filters, and electronics. Further, carbon nanotubes are the subject of vast research for uses in medical devise and as building blocks for every day products. 
     One of the problems commonly associated with carbon nanotube systems is the tendency of the carbon nanotubes and nanofibers to form agglomerates when incorporated into a matrix. This is due to the small size and high energy content of the carbon nanotubes and decreases the efficiency of additive and matrix interactions. 
     Accordingly, although great strides have been made in the area of carbon nanotube systems, many shortcomings remain. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The novel features believed characteristic of the embodiments of the present application are set forth in the appended claims. However, the embodiments themselves, as well as a preferred mode of use, and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a simplified schematic of a system in accordance with the present invention; 
         FIG. 2  is an oblique view of a multiwall carbon nanotube in accordance with the system of the present invention; 
         FIG. 3  is a flowchart of a method in accordance with the present invention; 
         FIG. 4  is a flowchart of the method of treating carbon nanotubes in accordance with the present application; 
         FIG. 5  is a table of analysis of a composite material created via the system and method of the present invention; 
         FIG. 6  is a series of graphs demonstrating the particle size distribution associated with carbon nanotube particles of  FIG. 1 ; 
         FIG. 7  is an SEM image of a dispersion curve of water suspension with carbon nanotubes; 
         FIG. 8  is a TEM image of a dispersion curve of water suspension with carbon nanotubes; and 
         FIG. 9  is a graph of the analysis of composite material strength of carbon nanotube particles in formaldehyde resin. 
     
    
    
     While the system and method of use of the present application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present application as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Illustrative embodiments of the system and method of use of the present application are provided below. It will of course be appreciated that in the development of any actual embodiment, numerous implementation-specific decisions will be made to achieve the developer&#39;s specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. 
     The system and method of use in accordance with the present application overcomes one or more of the above-discussed problems commonly associated with conventional carbon nanotube systems. Specifically, the present invention provides a means to create composite material with aggregate stability of carbon nanotube polymer matrix for use in a variety of products. In addition, the present invention provides a means to utilize carbon nanomaterial treatment for the improvement of its aggregate stability when introducing into phenolic matrix. These and other unique features of the system and method of use are discussed below and illustrated in the accompanying drawings. 
     The system and method of use will be understood, both as to its structure and operation, from the accompanying drawings, taken in conjunction with the accompanying description. Several embodiments of the system are presented herein. It should be understood that various components, parts, and features of the different embodiments may be combined together and/or interchanged with one another, all of which are within the scope of the present application, even though not all variations and particular embodiments are shown in the drawings. It should also be understood that the mixing and matching of features, elements, and/or functions between various embodiments is expressly contemplated herein so that one of ordinary skill in the art would appreciate from this disclosure that the features, elements, and/or functions of one embodiment may be incorporated into another embodiment as appropriate, unless described otherwise. 
     The preferred embodiment herein described is not intended to be exhaustive or to limit the invention to the precise form disclosed. It is chosen and described to explain the principles of the invention and its application and practical use to enable others skilled in the art to follow its teachings. 
     Referring now to the drawings wherein like reference characters identify corresponding or similar elements throughout the several views,  FIG. 1  depicts a simplified schematic of a system  101  in accordance with the present application. It will be appreciated that system  101  overcomes one or more of the above-listed problems commonly associated with conventional carbon nanotube systems. 
     In the contemplated embodiment, system  101  includes carbon nanotube and/or nanofiber particles (CNM)  103 . It should be understood that the carbon nanotubes can consist of single, double, or multi-wall nanotubes. It should further be appreciated that carbon nanotubes can be purchased within the industry, or alternatively, can be created. One means of creating carbon nanotubes for use in the present invention consists of using a unit with the application of atmospheric pressure high voltage discharge. 
     The carbon nanotubes (CNM) are incorporated with a binder  105  via a technique known in the art, such as through the use of a dissolver, to create a resin  106  to be applied to a grid  107  made of glass fabric. After the saturated glass fabric is dried, such as through the use of an oven, the breaking load of the matrix  109  can be analyzed using conventional methods. It should be appreciated that due to the method described herein, the matrix  109  includes the carbon nanotubes  111  having a relatively even distribution, which improves stability and predictability. 
     In  FIG. 2  an oblique view of a multiwall carbon nanotube  201  (CNM Particles) is shown. It should be appreciated that carbon nanotube  201  can be used in system  101 . Carbon Nanotube  201  includes a plurality of rolled walls forming a cylindrical shape. It is understood that these particular CNM particles include unique properties, such as being resistant to chemicals. As described above, conventional uses of carbon nanotubes pose challenges due to their high energy content and small size. The system and method of the present invention provides a means to treat the CNM particles so as to improve its stability, thereby making the CNM particles more usable. 
     In  FIG. 3 , a flowchart  301  depicts the method associated with system  101 . A plurality of composite test samples are created by first carrying out submicron emission of the CNM particles, as shown with box  303 . In the preferred embodiment, this procedure is carried out by specific stages, shown in  FIG. 4 , flowchart  401 . First, the CNM particles receive ultrasonic treatment, as shown with box  403 . Then there occurs the division of water suspension with surface-active substances (SAS) by size fraction, as shown with box  405 . This is followed by filtration, as shown with box  407 . In the present embodiment, SAS was presented by cationic dodecyltrimethylammoniom bromide (DTAB). 
     Referring back to  FIG. 3 , flowchart  301 , a dispersion analysis of water suspension of the CNM particles is carried out by particle size laser diffraction analyzer Fritsch “analyzette 22”, Nanotec, as shown with box  305 . CNM particles are then introduced into the binder and mixed in a dissolver, as shown with box  307 . The resin is then mixed into the dissolver by a special miller at about 1400 rpm for 30 minutes, and the finished resin is then applied to the glass grid, as shown with boxes  309 ,  311 . It should be understood that the amount of additive is determinable according to mass. 
     The saturated glass grid is dried, preferably by an oven technique at a temperature of approximately 100-105 degrees Celcius for 30 minutes, as shown with box  313 . It should be understood that this step causes the evaporation of binder volatile components. The dried grid is then cut into a plurality of segments to be analyzed for one or more features, such as breaking load, as shown with boxes  315 ,  317 . 
     It should be appreciated that one of the unique features believed characteristic of the present application is the method of applying the carbon nanotubes to a glass grid. It should be appreciated that this method has shown to produce a system with aggregate stability of carbon nanotube polymer matrix, which provides for improved predictability of the composite structure. This allows for improved use of carbon nanotubes in composites for uses such as in aircrafts, the carbon nanotubes increasing the strength and stiffness of the composite structure. 
     In  FIG. 5 , a table  501  demonstrates the results of the analysis of the breaking load of a plurality of segments of glass grids saturated by phenolic binder with carbon nanostructure additives of increasing saturation. As shown, the percentage of CNM additive increases from 0% to 0.05%. As further demonstrated, it can be concluded that the introduction of carbon nanomaterial additives in phenolic binder leads to an increase of breaking load, when the carbon nanomaterial in resin is 0.005%. 
     It should further be understood and appreciated that the quality and physical chemical properties of the initial glass grid, as well as the content of the binder can play a role in the strength (breaking load) of the saturated grid. 
     Another unique feature believed characteristic of the present application is the utilization of carbon nanomaterial treatment for the improvement of aggregate stability when introducing into phenolic matrix. 
     In  FIG. 6 , a series  601  of graphs demonstrate particle size distribution with regard to the carbon nanomaterial particles in three different settings. As shown in the first graph, particle size distribution in as-produced CNM particles is shown. The second graph demonstrates particle number distribution in submicron fraction with dodecyltrimethylammonium bromide (DTAB) additive. It can be seen from this graph that the CNM particle material with DTAB contains submicron fraction of about 90%. In the last graph of  FIG. 3 , particle number distribution in submicron fraction with distilled water is shown. It should be appreciated and understood from this analysis that application of cationic SAS DTAB in the process of preliminary treatment is the promising for the improvement of aggregate stability of carbon nanomaterial when introducing into a phenolic matrix. 
     It should be appreciated that the system and method discussed herein, provides analysis for the creation of a composite material with improved strength. This analysis allows for statistics and analysis to create a composite material with a desired breaking load via altering a percentage of carbon nanotube percentages. 
     Another unique feature believed characteristic of the present application is the creation of a composite with an increased strength, making the composite suitable for use with its wear resistance in a final product. 
     In  FIGS. 7 and 8 , an SEM image  701  and TEM image  801  show the dispersion curve of water suspensions of CNM with DTAB. It can be seen from image  701  and  801  that material with DTAB contains submicron fraction of about 90%. 
     In  FIG. 9 , a graph  901  further demonstrates the dependence of composite material strength on CNM content in formaldehyde resin. As shown, the highest strength was found at the 0.005% of CNM content. It should be appreciated that the system and method discussed herein, provides analysis for the creation of a composite material with improved strength. This analysis allows for statistics and analysis to create a composite material with a desired breaking load via altering a percentage of carbon nanotube percentages. 
     It should be appreciated that the system and method discussed herein, provides analysis for the creation of a composite material with improved strength. This analysis allows for statistics and analysis to create a composite material with a desired breaking load via altering a percentage of carbon nanotube percentages. 
     In the present invention, the treated carbon nanotube composite shows improved aggregate stability and provides a means to increase the strength of a glass grid. 
     The particular embodiments disclosed above are illustrative only, as the embodiments may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. It is therefore evident that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the application. Accordingly, the protection sought herein is as set forth in the description. Although the present embodiments are shown above, they are not limited to just these embodiments, but are amenable to various changes and modifications without departing from the spirit thereof.