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Process for Producing Polymers with Improved Melt Flow Characteristics This technology simplifies manufacturing processes for plastics while also improving melt flow characteristics of polymers. It is a method for inexpensive... Read More This technology simplifies manufacturing processes for plastics while also improving melt flow characteristics of polymers. It is a method for inexpensive synthesis of monomers for production of hyperbranched polymers (HBP). These polymers maintain desirable properties of linear polymers, such as thermal and chemical stability, while also maintaining high solubility and low viscosity. This technology offers the plastics additives industry a way to produce an optimal melt flow product while simplifying and reducing costs of the manufacturing process. It can be used to produce coatings, additives, or stand-alone polymers as well as other materials. It is thermally stable and can conform to any architecture needed. The technology includes methods for producing AmBn monomers and for producing high molecular weight (MW) star, linear, hyperbranched, and dendritic polyethermides (PEIs) from those monomers and their various combinations. Careful control of the chemistry of the monomers can selectively target production of processible, highly branched (hyperbranched) polymers that are mechanically, thermally, and hydrolytically stable as well as resistant to oxidative degradation. The process typically takes an aromatic monomer containing silylated phenols and fluorphthalimed reactive groups (ABn) types monomer and reacts it with a catalytic amount of cesium fluoride in high boiling, polar, aprotic solvents to produce a high-MW polymer This technique produces polymers that are highly amorphous and easily isolated from crystalline monomers that are easily synthesized and purified in three steps from inexpensive commercial starting materials. Further modifications produce a polymer with physical properties that are dominated by the endgroup functionalities and not by the repeat unit. The process controls the degree of branching and the polymer's structure, thereby targeting and controlling physical properties that lie between those of a linear and a "perfect" dendritic structure. The degree of branching (DB) of a polymer is defined on a scale from 0 to 1, with linear polymers approaching 0 and dendritic (maximally branched) polymers approaching 1. Those in between are termed branched or hyperbranched. This technology can produce polymers exhibiting the entire range of branching. Physical properties of dendritic macromolecules, such as crystallinity, viscosity and solubility, are determined by their unique globular shape and the endgroups that occupy their periphery. Techniques for producing high MW, "perfect" dendrimers require many synthetic steps that increase the cost and limit the scale of production. This method has few synthetic steps and provides macromolecules with properties very similar to dendrimers with a fraction of the time and cost. The physical properties of linear polymers are determined by intermolecular interactions and the structure of the repeat itself. Linear polymers increase in viscosity and decrease in solubility as their MW increases. For uses such as coatings or films, this quality makes the processing difficult. This technology can create highly branched, high-MW polymers with characteristics of linear polymers but much lower viscosities and much higher solubilities. This makes it ideal for use as an additive to commercially available polymers for reducing the melt and/or solution viscosity without compromising the physical properties of the parts or composites (e.g., injection molded) being created. Since the materials are high molecular weight, they are ideal candidates as viscosity reducers for coatings to reduce VOC content. The synthesis of hyperbranched monomers, historically costly and difficult, yields only small quantities of material. Techniques for improving the scaleability of hyperbranched monomers have not produced polymers that can withstand severe chemical, mechanical, thermal, or oxidative conditions. This new technology produces hyperbranched polymers that are amorphous solids with excellent chemical stability: they can withstand temperatures above 500 C in air and nitrogen, their chemical solubility profile can be easily modified, and they can be produced in bulk quantities while still maintaining their preferred characteristics. Lastly, the technology can effectively eliminate separation of polymer phases within blended products. It can camouflage hyperbranched polymers by selecting endgroups or linear polymer chains that make the particle compatible or homogenous within the matrix. Applications Specialty chemicals (e.g., plastics, fibers, adhesives, appliances, carpeting, furniture) Automobiles (e.g., plastic components, rubber tires and hoses, fibers, paint, lubricants, adhesives and sealants, electronic components) Electronics (e.g., chemicals, photo resists, polymers, specialty gases) Construction (e.g., plastics used in pipes and siding) Benefits This technology lowers the costs associated with synthesizing monomers used in producing hyperbranched polymers that maintain advantageous stability, solubility, and viscosity characteristics. Possesses Ideal Characteristics: In addition to maintaining the thermal and chemical stability characteristics of linear polymers, this technology also provides high solubility and low viscosity. Scalable: This polymer can be produced in bulk quantities. Stable in Production: Even when mass produced, the polymer maintains the preferred characteristics. Versatile: This technology can be used as a coating, an additive, a stand-alone polymer, or in other ways. Easy to Incorporate: This technology's high solubility and low viscosity characteristics simplify the manufacturing process when used as an additive.
One-Part Liquid Composite Molding Technique This technique for liquid composite molding uses a solid catalyst recrystallized onto preplaced fiber reinforcements to produce high-strength polymer matrix... Read More This technique for liquid composite molding uses a solid catalyst recrystallized onto preplaced fiber reinforcements to produce high-strength polymer matrix composites. The polymerization is initiated by the preform itself, eliminating the need to mix multiple resins and catalysts before filling the mold. Having polymerization triggered by the preform simplifies the process, saves time, and eliminates mixing equipment. Liquid composite molding processes have been popular since the 1940s. In the last 10 to 15 years, significant improvements have been made in developing low-viscosity thermosetting resin systems necessary to obtain high fiber volume parts. Also, automatic methods like weaving, braiding, and knitting have greatly reduced the cost of producing fiber preforms. All liquid composite molding processes require that the resin injected into the mold is a reactive liquid. Some resins such as epoxy and urethane are highly reactive and must be kept separate until just before they are injected into the mold. Other resins are activated by a catalyst in the holding tank. These multipart resin systems require complex mixing, metering, and use of injection equipment with accurate ratio control. The multipart resin systems also may require heating tanks, hoses, pipes, and pumps; motionless mixing; efficient circulation to help prevent cure or degradation of the resin in a holding tank; and easy and safe cleaning/purging. This new liquid composite molding technique uses a one-part monomer and a solid catalyst crystallized onto the fiber reinforcement. The polymerization is initiated by the preform itself, eliminating the need to mix or add multiple resins and catalysts before filling the mold. Since it uses a single resin, the process also eliminates the need for the mixing equipment and reduces the heating and cleaning requirements of the injection equipment. The best material system for use with this technology is one that uses polydicyclopentadiene (pDCPD). This polymer forms very rapidly at room temperature by a ring-opening metathesis polymerization (ROMP) of its low-viscosity monomer. The first step in this process requires recrystallizing the catalyst onto the fiber preform. The reactive fiber preform is then placed into the mold, the mold is closed, and the monomer is injected into it. Once the monomer has had time to react with the catalyst on the fiber preform and polymerize, the completed part is removed from the mold. Applications This technique can be used in liquid composite molding, such as resin transfer molding (RTM), vacuum-assisted RTM (VARTM), and structural reaction injection molding (SRIM), for parts with end-use applications in: Aerospace Sports Recreation Marine and Automotive Equipment Ballistics Electronics Benefits Because multiple resins and catalysts do not need to be added or mixed before being pumped into the mold, this process: Simplifies production: This technique provides a simpler process that requires fewer steps for producing polymer matrix composites Reduces equipment costs: This technique eliminates the need for complex metering and mixing equipment Reduces maintenance costs: The technique reduces the heating and cleaning requirements of the injection equipment
Microvascular Networks and Composite Materials Using Sacrificial Fibers This technology is a biologically inspired 3D microvascular networks within composite materials provide damage management and active temperature regulation. ... Read More This technology is a biologically inspired 3D microvascular networks within composite materials provide damage management and active temperature regulation. Details A novel fabrication of microvascular structural material. Imagine a responsive material that has the ability to react to physical changes by delivering a functional fluid to vital, often inaccessible areas. In nature, this is accomplished through complex vasculature that transports vital fluids to tissues throughout an organism in order to regulate temperature, deliver nutrients, or begin the healing process. Scientists at the University of Illinois have taken their cue from such biological systems in fabricating a 3-dimensional vascular network within a polymer or polymer composite material that can be filled with virtually any fluid. The process is rapid, scalable and easily integrated into existing manufacturing processes with commercially available precursors. In the materials world, this system has the potential to help create longer lasting, safer and fault tolerant products. Through chemical decomposition of the sacrificial fiber relative to the matrix, the original fiber is removed from the matrix leaving behind a pervasive 3D interconnected network of microchannels that can be filled with a fluid either by using capillary action or by pumping. The choice of fluid can impart functionality to the matrix material such as self-healing, temperature regulation, or imparting visibility to areas where damage occurred through the use of a conspicuous dye. These microvascular composite materials can distribute these active fluids for reactions within the matrix in areas that are normally problematic to reach within components. The sacrificial fibers can be handled simultaneously with reinforcing fibers and decompose upon exposure to an external trigger such as processing temperature. This novel material system has the potential to restore structural integrity and extend the safety, reliability and operating life of countless components that are used everyday in numerous industry applications. For example, composite materials play an integral role in everything from aerospace and automotive applications to building materials and must maintain their integrity after repeated thermo-mechanical loading. Under such conditions, micro-cracks can develop over time within the structure significantly weakening its strength. Incorporation of a self-healing capability within the composite can instantly and permanently repair the damage, allowing the composite to retain its structural and mechanical integrity and prolonging its operational life. Figure 1: Creation of 3-D microvascular network. (A) 3-D woven preform, (B) integration of sacrifical fibers, (C) Resin infusion, (D) 3D woven composite and (E) formation of 3-D microvascular network. Applications This novel material system has the potential to restore structural integrity and extend the safety, reliability and operating life of countless components that are used everyday in numerous industry applications. Composite materials play an integral role in everything from aerospace and automotive applications to building materials and must maintain their integrity after repeated thermo-mechanical loading. Under such conditions, micro-cracks can develop over time within the structure significantly weakening its strength. Incorporation of a self-healing capability within the composite can instantly and permanently repair the damage, allowing the composite to retain its structural and mechanical integrity and prolonging its operational life. Rubber and latex industries could use this material to make improvements to existing products making them safer and longer-lasting. A self-healing tire would significantly increase safety on the road as well as reduce replacement costs. A self healing hose in air brakes for trains and trucks would significantly diminish the catastrophic risk of a failure to the brake system. Latex gloves are the primary barrier between a caregiver and possible infectious agents and tears and puncture can happen without the wearers knowledge. Using this microvascular material filled with a conspicuous dye would alert the wearer of a tear sooner. Alternatively, an anti-infective agent could be used and in the event of a tear or puncture, this agent would be released and help prevent infection. Although lithium ion batteries are gaining attention for use in automotive applications, their performance suffers at high temperatures, which are associated with quicker discharge and safety hazards. They must come with sophisticated battery management systems to maintain the proper temperatures in cars. Battery pack housing would benefit from the incorporation of a 3D microvascular material containing a temperature regulating fluid within the capillaries dissipating heat from hot spots and helping to maintain the proper thermal conditions for optimal battery life. Similarly, as computer technology moves to high-density storage and ultra-fast processing, thermal management becomes an issue. By integrating a microvascular material with a liquid capable of absorbing heat, one could create an effective and compact thermal management system for high density computational applications. Benefits Provides 3-D microvascular network for self-healing or active temperature regulation Process is scalable and can be woven into large mats All components of process are commercially available
Advanced Technique for Processing Sacrificial Fibers Researchers from the University of Illinois have developed a new method for making sacrificial fibers. This method can be used to produce larger and more complex... Read More Researchers from the University of Illinois have developed a new method for making sacrificial fibers. This method can be used to produce larger and more complex microvascular networks in polymers and fiber-reinforced composites. The better mixing method means that the networks left will be more uniform. These microvascular networks are useful for cooling, self-healing applications, or for weight saving designs.
Advanced Technique for Processing Sacrificial Fibers Researchers from the University of Illinois have developed a new method for making sacrificial fibers. This method can be used to produce larger and more complex... Read More Researchers from the University of Illinois have developed a new method for making sacrificial fibers. This method can be used to produce larger and more complex microvascular networks in polymers and fiber-reinforced composites. The better mixing method means that the networks left will be more uniform. These microvascular networks are useful for cooling, self-healing applications, or for weight saving designs.
Flame Retardant Microcapsules for Batteries University of Illinois researchers have developed a method of placing flame retardant into lithium-ion batteries without impacting battery performance. This... Read More University of Illinois researchers have developed a method of placing flame retardant into lithium-ion batteries without impacting battery performance. This technology gains the same safety improvement of experiments done by others involving mixing a retardant directly into the battery without drawbacks.
Environmentally Stable Core-Shell Microcapsules With Polymeric Protective Coatings Researchers at the University of Illinois have developed a method of protecting microcapsules from harsh environments. This added barrier will enable microcapsules... Read More Researchers at the University of Illinois have developed a method of protecting microcapsules from harsh environments. This added barrier will enable microcapsules to maintain their liquid core in high temperature, causatic chemical contact, or physical abuse for long periods of time. The technology adds very little time and expense to the manufacturing of microcapsules.
Polymers for Non-Aqueous Flow Batteries Researchers from the University of Illinois have synthesized new redox active polymers for use in non-aqueous flow batteries When combined with a size exclusion... Read More Researchers from the University of Illinois have synthesized new redox active polymers for use in non-aqueous flow batteries When combined with a size exclusion membrane, these polymers can be used without significant crossover between cells allowing flow cells to increase redox active species concentration while also increasing energy density, power and efficiency.
Brightness Equalized Quantum Dots Dr. Smith from the University of Illinois has developed a series of colloidal quantum dots that have precisely matched brightness among different colors. The... Read More Dr. Smith from the University of Illinois has developed a series of colloidal quantum dots that have precisely matched brightness among different colors. The brightness of the quantum dots is quantitatively equalized on single particle and ensemble level, using a core/shell/shell structure. Such brightness equalized quantum dots can be applied for quantitative and multiplex bio-imaging, as well as in optoelectronic devices and displays.
Scaffold-Free Three Dimensional Battery Electrode Dr. Paul Braun from the University of Illinois has developed a new battery cathode without a scaffold. The new structure relies on the active metal oxide material... Read More Dr. Paul Braun from the University of Illinois has developed a new battery cathode without a scaffold. The new structure relies on the active metal oxide material to provide support for the weaker current collector during the manufacturing process, thereby disposing the need to use any inactive material as a support structure. This new method and structure carries a higher volumetric energy density because there is no room wasted on a scaffold.

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