Table of Contents for Definitions (click on a term to jump to the definition)
■ Aramid (aromatic amide) polymers Aramid (aromatic amide) polymersDuPont’s Kevlar is the protypical aramid polymer. The word aramid is a contraction of “aromatic amide.” Non-aromatic amides include Nylon and biological amino acid polymers (e.g., proteins and enzymes). When aromaticity is added to an amide polymer, it becomes stronger and more stable at higher temperatures. For example, Dupont’s Nomex polymer is used to make oven mitts. Although aromaticity can also make aramid polymers semiconducting, there are steric flaws in Kevlar and Nomex that prevent semiconductivity that are not present in Nanopolymer System’s aramid polymers. See the polymer-comparison page for visual diagrams of standard and vector-directional aramid polymers. Aramid polymers are not usually recycled. However, they have the potential to be recycled back into monomers by "hydrolysis" under extreme conditions (strong alkali at high temperatures). The value of standard aramid monomers (with only two functional groups) is not sufficient to justify recycling. However, the higher value of vector-directional monomers (with four functional groups) changes this economics and makes recycling more economically favorable. [Return to table of contents.] Aromaticity, and aromatic monomers and polymersThe original definition of "aromatic" applied to aromatic oils (cinnamon, vanilla, ginger, clove, wintergreen, thyme, menthol, etc.). When the structures of some of these oils were determined more than a hundred years ago, they were found to contain benzene-like rings of alternating double and single bonds. Chemists named this pattern of double bonds as aromatic, after the notable scent properties of the essential oils. Later, aromaticity was discovered to be a general class of unusually stable molecular structures involving alternating double and single bonds which "blended" into an intermediate bonding state. The benzene ring, a hexagonal structure with three double bonds and three single bonds (see illustrations on other pages), was discovered to contain six identical one-and-a-half bonds. In other words, the bonds had 50% double-bond character and 50% single-bond character. There are two primary advantages that derive from using aromatic ring systems to build nanostructures. One, the aromatic ring systems are flat and rigid. This flatness and rigidity extends outward from the ring to atoms and chemical groups that are attached to the aromatic rings. Second, aromatic systems have a strong tendency to interact (resonate) with other aromatic systems to which they are directly connected. By using aromatic-compatible primary and secondary reactive groups, the aromaticity of the ring system is extended into the reactive groups that form the polymer linkages. And by using primary reactive groups that react to form an aromatic linkage, the resonance of each adjacent monomer extends through the linkage to enforce flatness of the entire polymer backbone. See heterocycles for additional discussion. [Return to table of contents.] Aromaticity, and aromatic monomers and polymersThe original definition of "aromatic" applied to aromatic oils (cinnamon, vanilla, ginger, clove, wintergreen, thyme, menthol, etc.). When the structures of some of these oils were determined more than a hundred years ago, they were found to contain benzene-like rings of alternating double and single bonds. Chemists named this pattern of double bonds as aromatic, after the notable scent properties of the essential oils. Later, aromaticity was discovered to be a general class of unusually stable molecular structures involving alternating double and single bonds which "blended" into an intermediate bonding state. The benzene ring, a hexagonal structure with three double bonds and three single bonds (see illustrations on other pages), was discovered to contain six identical one-and-a-half bonds. In other words, the bonds had 50% double-bond character and 50% single-bond character. There are two primary advantages that derive from using aromatic ring systems to build nanostructures. One, the aromatic ring systems are flat and rigid. This flatness and rigidity extends outward from the ring to atoms and chemical groups that are attached to the aromatic rings. Second, aromatic systems have a strong tendency to interact (resonate) with other aromatic systems to which they are directly connected. By using aromatic-compatible primary and secondary reactive groups, the aromaticity of the ring system is extended into the reactive groups that form the polymer linkages. And by using primary reactive groups that react to form an aromatic linkage, the resonance of each adjacent monomer extends through the linkage to enforce flatness of the entire polymer backbone. See heterocycles for additional discussion. [Return to table of contents.] Atomic-precision manufacturingAtomic-precision manufacturing is the ability to make commercially useful products in which every atom in the structure is in a precise location relative to every other atom in the structure. This definition is encoded in the U.S. Department of Energy's roadmap for future energy security. [Return to table of contents.] The bottleneck in nanotechnology commercializationThe current bottleneck in nanotechnology commercialization is the high manpower, energy, time and capital costs of working with (and trying to simultaneously optimize) multiple top-down nanostructuring methods. [Return to table of contents.] Bottom-up manufacturing and top-down manufacturingBottom-up manufacturing with NSC’s polymers is spontaneous and self-organizing, as opposed to top-down manufacturing which requires post-polymerization processing (drawing, laminating, doping, casting, coating, polishing, forging, machining, freezing, surface deposition, blending, etc.). The spontaneity of the assembly process is enabled by chemical energy in the monomers. The self-organizing feature is enabled by a single thermodynamic minimum for the polymer linkage “posture” (conformation). With only one energetically favored posture for every linkage, the polymer backbone ends up with a structured backbone. In other words, the polymer grows with vector directionality (a specific orientation in three-dimensional space). Biology is an example of bottom-up manufacturing. For a discussion of the benefits and liabilities of biological bottom-up manufacturing compared to NSI's vector-directional polymers, see the technology page. [Return to table of contents.] ElectrolyteThe electrolyte is the ionic part of the battery that moves when the battery is charged or discharged. In some batteries, positively charged ions (cations) move in one direction, and negatively charged ions (anions) move in the other direction. In modern, more sophisticated batteries, the anions are "frozen in place" by being attached to polymers, or by being crystaline additives mixed into the electrolyte. In this newer kind of battery, only the cations move. Cation movement is an essential aspect of battery performance. There is a one-to-one correlation between positive charges moving inside the battery and electrons moving outside the battery (through wires, motors, phones, computers, etc.). Since the efficiency of electron movement through wires is high, the inefficiency of cation movement within the battery is a major limitation on battery performance. We propose to change this by making cation movement highly efficient. The loss of energy through cation movement is directly related to ion hopping. The longer the hop, the more energy is lost. The shorter the gaps between the anions, the shorter the hops that the cations need to make, and the less energy is lost to internal resistance. Intercalating agents (particles with negatively charged surfaces) are added to batteries to provide ion-hopping "islands" for cations to use. Iron phosphate nanocrystals are one state-of-the-art intercalating agent for lithium ion batteries. But this only shortens the hopping distance. NSI's solution, a nanostructured-polymer electrolyte with continuous ion-conducting pathways, is designed to eliminate ion-hopping completely, or to reduce it to its theoretical minimum. This lost energy from ion hopping shortens how long the battery lasts on a single charge, and makes the battery run hot. Hot batteries degrade faster, shortening their lifespan (the number of charge-discharge cycles). The efficiency of ion movement has widespread and profound consequences to battery performance. For example, degraded batteries store less charge and have increased chances of fires and explosions. The efficiency of nanostructural self assembly allows very large ion-conducting surface areas to be produced from small amounts of monomer. One teaspoon of electrolyte polymer has a surface area greater than a football field. See also Nafion, a state-of-the-art perfluorocarbon polysulfonyl electrolyte polymer, ion hopping and sulfonate groups for further information. [Return to table of contents.] End-run risksBusiness risks can be segmented into different categories: financial, management, technological, etc. One of the technological risks is end-run risk in which a new technology bypasses an older technology and renders it obsolete. This is a particular concern with platform technologies. We are addressing this risk by patenting all possible aromatic polymer systems capable of performing nanostructural self-assembly, and by a global patent of monomer-linkage design. This concern has been a long-standing element of our IP-development strategy. [Return to table of contents.] Energy costs and power costsEnergy and power requirements increase in a non-linear (exponential) manner as the requisite scale of top-down nanostructuring approaches the nano (molecular) scale. See Power Costs (below) for further explanation. Energy savings also follow from reduction or elimination of top-down methods. [Return to table of contents.] HeterocyclesThe most basic aromatic structure is the benzene ring, with six carbon atoms. When some other atom is substituted for a carbon atom, the resulting aromatic structure is called a heterocycle (hetero meaning other or different, and cycle meaning ring). The closer the non-carbon atom is to carbon, the greater the aromaticity. Nitrogen heterocycles are the most stable. Boron, oxygen, phosphorus and sulfur heterocycles are less stable. [Return to table of contents.] Iminol polymersIminol polymers are structural variations (tautomers) of aramid polymers. Both iminols and aramids have a carbon-nitrogen linkage with a double bond. They differ in the placement of the double bond. With iminols, the double bond is between the carbon and nitrogen atoms, which places it in the polymer backbone. With aramids, the double bond is between carbon and oxygen, outside the backbone. Although the drawings of iminols and aramids show the double bonds in a single, specific position, this is not really what exists at the molecular level. The double bonds “resonate” (vibrate or switch) between both positions, and to a lesser extent with the other immediately adjacent bonds, which kind of “blurs” the actual bond position over many positions. But the relative dominance of each double-bond position is still different between aramids and iminols. With aramids, it is 60:40 carbon-oxygen over carbon-nitrogen, and with iminols it is 40:60 carbon-oxygen over carbon-nitrogen. Steve Fowkes likes to note that these resonance forms (tautomers) for aramids are rarely ever drawn in textbooks, despite being 60:40 in ratio, yet enol tautomers, which are 90:10 in ratio, are routinely drawn as tautomeric pairs in textbooks. Maybe this is one reason why aromatic iminol polymers were not invented 30 years ago. The tautomerization of the amide linkage into the iminol form is caused by the polarization of the linkage by the hydrogen bond donor and acceptor. The hydrogen-bond acceptor is an annular (ring) nitrogen atom at the ortho position to the amine group. This annular nitrogen atom is a Lewis-base feature that stabilizes only the iminol tautomeric form of the polymer linkage. An ortho-positioned hydroxy group on the acid monomer provides the corresponding Lewis-acid (hydrogen-bond donor). The hydrogen-bond push-pull polarizes the polymer linkage and 1) thermodynamically stabilizes the linkage system when the virtual ring systems and hydrogen bonds are formed and 2) thermodynamically destabilizes the polymer linkage when either monomer is 180° out of the favored conformation. [Return to table of contents.] Intercalating agentsIntercalating agents are microparticulate and nanoparticulate additives to battery electrolytes to improve ion conductivity. Intercalating particles have a negatively charged surface to facilitate the movement of positively charged ions. One example of an intercalating agent for lithium-ion batteries is iron phosphate. The negatively charged phosphate groups attached to the iron atoms provides islands for ion hopping that improves lithium conductivity. [Return to table of contents.] Ion hoppingWithout NSI’s nanostructured-polymer methods, sulfonyl groups repel each other and tend to distribute themselves randomly throughout the polymer compartment. This makes ion hopping the default ion-conduction process. Even with intercalating agents, hopping is dominant (although shorter). With our separations of 0.35 nm (sulfonyl center-to-center) and less than 0.1 nm (sulfonyl surface-to-surface), ion hopping should be reduced to its theoretical minimum. [Return to table of contents.] Labor costsLabor costs are a major fraction of the costs of nanotechnology commercialization. During the research phase, teams of highly qualified experts must not only optimize each top-down method, but also assess any adverse effects (interferences) from other top-down methods. There is also significant overhead in scientific coordination between teams and corporate oversight of the complicated teamwork of the R&D effort. During the development phase, quality control issues during scale-up and manufacturing can be exceedingly challenging. Drift in quality control in one top-down process can sabotage quality in another top-down process in non-linear ways. Typically, significant compromises are required to accommodate mass-production scaling. These high manpower costs increase capitalization requirements to the point of infeasibility for many nano ventures. This has been a major factor in the decreased popularity of nanotech in investment circles over the last ten years. Labor costs savings are anticipated to follow the reduction or outright elimination of top-down nanostructuring methods. [Return to table of contents.] MetamaterialsMetamaterials are "artificial" materials (not found in nature) engineered to provide "unnatural" properties. These materials usually gain their properties from their unusual structures rather than their composition. This can be accomplished by 1) including small inhomogeneities to enact effective macroscopic behavior, or 2) positioning and orientation of identical or near-identical subunits in some kind of pattern or array. Optical metamaterials exhibit electromagnetic properties based on subunits that differentially interact with the electrical and magnetic components of photons (light). With subunits etched on layers of silicon circuitry, these subunits are small enough to accommodate microwave and infrared wavelengths. We anticipate that smaller, organic structures might be organized (positioned and oriented) by vector-directional polymers (arrays and latices) to make a new generation of metamaterials capable of imaging structures with visible light. [Return to table of contents.] Monomers, polymers and oligomersMonomers are the smallest parts or subunits from which polymers can be assembled. The monomer ethylene is used to polyethylene. The monomer vinyl chloride is used to make polyvinyl chloride (PVC). These are A → A-A-A-A kinds of polymers, usually made by free-radical reactions, which are non-reversible. There are dehydration-condensation polymers that follow an A + B → A-B-A-B reaction scheme, which are reversible. For examples, monomers terephthalic acid and para-phenylenediamine are used to make Kevlar, and alkyl diacid and alkyl diamine monomers are used to make Nylons. Small polymers (sequences of two, three, five or ten monomers) are called oligomers. [Return to table of contents.] NafionNafion polymer is arguably today’s most sophisticated electrolyte polymer. Like many electrolytes of old and our first-product electrolyte, Nafion is a polysulfonyl polymer. Nafion is unique in having a backbone of perfluorocarbon. Without NSI’s nanostructured-polymer methods, sulfonyl groups repel each other and tend to distribute themselves randomly throughout the polymer compartment. This makes ion hopping the default ion-conduction process. Even with intercalating agents, hopping is dominant (although shorter). With our separations of 0.35 nm (sulfonyl center-to-center) and less than 0.1 nm (sulfonyl surface-to-surface), ion hopping should be reduced to its theoretical minimum. [Return to table of contents.] Oligomers, monomers and polymersMonomers are the subunits from which polymers can be assembled. Oligomers are small polymers made from two or more monomers. For example, in the A + B → A-B-A-B reaction scheme, if a huge excess of A monomer is used, you tend to get lots of A-B-A with a little bit of A-B-A-B-A and a tinier amount of A-B-A-B-A-B-A. These are all oligomers. Oligomers can also be heterogeneous. For example, ABC, ABACA, and ABACUS. In a nanostructural design system, oligomers are likely to become modular parts with characteristic structural features, like hinges, axles, pivots, arms, etc., that can be easily assembled into functional nanodevices. In biology, amino-acid oligomers are called peptides. [Return to table of contents.] Power costs and energy costsPower requirements increase in a non-linear (exponential) manner as the requisite scale of top-down nanostructuring approaches the nano (molecular) scale. Power savings also follow from reduction or elimination of top-down methods. With bottom-up methods, the energy for creating nanostructure is chemical. In other words, the power costs are invested 1) during the manufacture of the monomers themselves, 2) during the preparation of "activating agents" used to facilitate polymerization (if relevant), and 3) in the "unblocking" step of solid-phase (one-monomer-at-a-time) synthesis (if applicable). Therefore, power costs are linear (proportional to the amount of monomer used). They are linear in bulk nanopolymer reactions (i.e., A + B makes an ABABAB polymer sequences). And they are linear for step-wise reactions, i.e., A + B makes AB, then AB + C makes ABC, then ABC + XYZ makes ABCXYZ). In biological systems of nanostructural self assembly (of proteins, enzymes and nucleic acids), the chemical energy costs (provided by ATP) are also linear. This are huge energy advantages to bottom-up manufacturing when the "manufactured parts" are nano scale, or when the degree of nanostructuring approaches molecular perfection. NSI has the potential to tap both of these advantages. [Return to table of contents.] Rapid prototypingRapid prototyping is based on the simplicity of R&D teamwork between the engineering team and chemistry team and the quickness of performance assessments by the engineering team (in the absence of top-down interferences) and the rapidity of polymerization reactions by the chemistry team (in the absence of new-monomer synthesis). With only two primary teams to interface, management expenses (and delays) are also decreased. The simplicity of teamwork is the result of the lack of direct interferences between the organic chemistry teams and the engineering teams. Communication is definitely required, but changes in engineering specifications has minimal effect on the internal process within the chemistry team, and new monomer synthesis and changes in polymer recipes has minimal effects on the internal process within the engineering team. The technical and management challenges to each team tend to be entirely within each team. [Return to table of contents.] Scale upScale-up is the process of increasing volume of production. Some manufacturing methods are difficult to scale up. Nanopolymer scale up is facilitated by monomer availability and by the modular nature of monomers as chemical feed stocks within a polymerization process. In other words, product scale-up partially devolves into a monomer scale-up process. [Return to table of contents.] Step-and-repeat spin-off strategyNSI's current step-and-repeat formula for spin-off ventures is: Sulfonate groups and sulfuric acidSulfonate groups are the “attached” version of sulfate groups, which are the anion (negatively charged ion) found in sulfuric acid. Sulfuric acid is an excellent model for an electrolyte. Its strong acidity means that protons (and other cations, i.e., positively charged ions) do not “stick” to the sulfate anions; they are loose—and mobile. Looseness and mobility are good. The sulfate anion has two negative charges. To attach them to a polymer, one of those charges is used, and we are left with a sulfonate group with a single negative charge. [Return to table of contents.] TautomersTautomers are different structural forms of certain chemicals. Tautomers (from "tauto" meaning the same, and the Greek "meros" meaning part) involve a the shift of a hydrogen atom from one place on the molecule to another place. The vast majority of tautomers are in equilibrium with their counterparts. The hydrogen shifts back and forth. Usually, one dominates. For example, the enol tautomers are roughly 1% to maybe 10% of their ketone tautomers. In plain amides, the amide tautomer is slightly favored over the iminol tautomer. Although not well known, there are many substituted iminols that are known to be favored over their amide tautomers. When the structural differences involve shifts of atoms other than hydrogen, the correct term is isomerism. Isomers tend not to switch back and forth with their isomeric counterparts. Like tautomers, isomers have the same number and kinds of atoms, but they are arranged differently. Normal butanol (C4H10O) has the same chemical formula as iso-butanol (C4H10O) and tertiary butanol (C4H10O), but n-butanol has a straight backbone, iso-butanol has a branched backbone, and tert-butanol has a doubly branched backbone. They do not interconvert. Alpha-hydroxybutyric acid (alpha-hydrox, the cosmetic ingredient), beta-hydroxybutyric acid (a ketone fuel) and gamma-hydroxybutyrate (Xyrem-brand pharmaceutical) all have the formula C4H8O2 . Although all are nutrients and metabolically active, they do not interconvert, spontaneously or by any direct metabolic pathway. Tautomers are a special case of isomers. [Return to table of contents.] Thermoelectric conversionThe thermoelectric converter is a solid-state version of the Carnot heat engine, in which thermodynamic state changes are used to generate high-quality energy (electricity) from low-quality thermal gradients (waste heat). The enabling technology is a membrane, through which cations can pass freely but electrons cannot. The efficiency of the proton-hydrogen thermoelectric converter requires a membrane capable of conducting naked protons to reach the temperatures required for sufficient efficiency to become commercially competitive. Existing Nafion (perfluorosulfonyl polymers) membranes work well at relatively low temperatures (near the boiling point of water), but lose conductivity at higher temperatures because the membrane dries out. This is because Nafion does not provide a continuous ion-conducting pathway, but rather a disconnected network of ion-conducting pockets. All three of NSI’s ion-conducting polymer designs provide continuous ion-conducting nanostructures. [Return to table of contents.] Time and amortization costsPolymerization reactions are simple and quick. The average polymerization reaction for creating a prototype material can be affected in one day, assuming that the requisite monomers are already in the monomer library and available off the shelf. If not, synthetic time for the organic-chemistry team to make a monomer could vary from a week to possibly several months, depending on the degree of challenge and complexity of synthesis. Without "interferences" from top-down methods, the most time-consuming step in the R&D cycle is performance assessment by the engineering team. These time frames are quite short compared to current R&D processes limited by top-down manufacturing methods. Amortization is the time-associated costs of money or debt. The longer it takes to reach the marketplace, the greater the investment needed to launch a venture. Capital savings accrue from itemized power, labor and time savings, and decreased amortizations of such expenses. [Return to table of contents.] Top-down manufacturing versus bottom-up manufacturingBottom-up manufacturing with NSI’s polymers is spontaneous and self-organizing, as opposed to top-down manufacturing which requires post-polymerization processing (drawing, laminating, casting, coating, polishing, forging, machining, freezing, deposition, blending, etc.). The spontaneity of the assembly process is enabled by chemical energy in the monomers. The self-organizing feature is enabled by a single thermodynamic minimum for the polymer linkage “posture” (conformation). With only one energetically favored posture for every linkage, the polymer backbone ends up with a structured backbone. In other words, the polymer grows with vector directionality (a specific orientation in three-dimensional space). [Return to table of contents.] Vector directionality and vector-directional polymersA vector is a directional quantity. In mathematics, the quantity is often depicted by the length of an arrow, and the direction by the orientation of the head of the arrow to the tail. We apply this to polymers, where the magnitude of the vector is the size of the monomer and the direction of the vector is the angle created by the monomer relative to the previous monomer. Ordinary polymers do not have direction. Their linkages have freedom to rotate, hinge and pivot, which makes direction random. During polymerization, this randomness results in the finished polymer being a tangle of strands, much like cooked spaghetti when it is dumped into a colander. Another good analogy: regular polymers are like worms without spines, and vector-directional polymers are like vertebrate organisms with spines. The structural rigidity of the spine allows animals to have superior mechanical and structural competitiveness. [Return to table of contents.]
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