Our Regular Roundup of Notable Patents.
U.S. Patent 9,878,501 (Jan. 30, 2018), "Method of Manufacturing a Frangible Blade," Darek Tomasz Zatorski, Ian Francis Prentice, Randy M. Vondrell, and Andrew Breeze-Stringfellow (General Electric Co., Schenectady, N.Y.)
Fan blades for aircraft engines often experience damage from ingested birds or other objects. This often leads to catastrophic fracture with broken parts becoming flying missiles capable of damage leading to crashes. Zatorski et al. developed a frangible laminate that forms smaller, non-damaging particles when catastrophic failure occurs. Energy-releasing components are incorporated into the composite which induce a self-shredding process, forming harmless particles. These energy-releasing structures are strands of high-strength aromatic or metal wires as braids, weaves, or tapes integrated into the composite. These structures also include damage initiators such as metallic, ceramic, or composite wedges along with Teflon release agents to further promote shredding.
U.S. Patent 9,878,490 (Jan. 30, 2018), "Laser Beam Welding Method and Molded Components Fabricated Thereby," Jens Butzke, Stefan Wurthner, Nikolai Lamberts, Pierre Dubon, Sabine Bertram, and Heinz Caviezel (EMS-Patent AC, Domat/Ems, Switzerland)
Laser beam welding is attractive because of reduced localized heating and flexible geometry. However, the materials must have a combination of laser permeability and sorbability requiring laser-absorbing additives such as soot or carbon powder. Butzke et al. expanded its application by using two thermoplastic layers where one (A) absorbs the radiation and converts it to heat and the other component (B) is heated and welded. Welding occurs with 1,440 to 1,500 nm radiation. Absorbing additives in A include up to 2 wt% inorganic pigments or hindered amine light stabilizers a well as other aromatic derivatives.
U.S. Patent 9,879,099 (Jan. 30, 2018), "Polyethylene Composition Having High-Stress Cracking Resistance," Gerd Mannebach, Bernd Lothar Marczinke, Cerhardus Meier, Ulf Schuller, lakovos Vittorias, and Harilaos Mavridis (Basell Polyolefine GmbH, Wesseling, Germany)
Polyethylene materials with medium to high density have a good balance of mechanical properties and processability for geomembranes. However, environmental stress cracking resistance (ESCR) remains a problem. Mannebach et al. developed a polyethylene with good balance of ESCR and processability with a density of 0.930 to 0.945 of a polyethylene with a molecular weight more than 1,500,000 g/mol and a branching index of 0.55 or less. This index is the ratio of radius of gyration of the above resin to that of a linear polyethylene with a molecular weight 1,000,000 g/mol. Thus, the branching is filling up the empty space of the coil reducing chain coil relaxation, necessary for environmental stress cracking.
Long Chain Branching
U.S. Patent 9,879,101 (Jan. 30, 2018), "Long Chain Branched Polymers and Methods of Making Same," Youlu Yu, Eric D. Schwerdtfeger, Max P. McDaniel, Alan L. Solenberger, and Kathy S. Clear (Chevron Phillips Chemical Co., LP., The Woodlands, Texas)
Polymeric materials are used for a wide variety of products. However, limitations such as cracking, flexibility and endurance require polymers with improved properties. One approach is to change certain chain properties such as branching. Yu et al. found that polymerization with chromium polymerization catalysts with a low surface area support induce long chain branching and improve properties. These chromium catalysts include 50 to 80 percent inorganic oxides such as silica, alumina, or aluminophosphates. Monomers include ethylene and other monolefins. Long chain branching ranges from 1 to 30 long chains per million carbon atoms. Highly branched resins may be processed by extrusion, blow molding, injection molding, fiber spinning, thermoforming, or casting.
U.S. Patent 9,887,048 (Feb. 6, 2018), "Stretchable Supercapacitor and Method of Manufacturing the Same," Taeho Kim, Jangwook Choi and Yonghee Lee (Samsung Electronics Co., LTD., Gyeonggi-Do, South Korea and Korea Advanced Institute of Science and Technology, Daejeon, South Korea)
A capacitor is a device for storing charges. A supercapacitor is an electric double-layer capacitor or an electrochemical capacitor. When a voltage is applied to a supercapacitor, a double-layer is formed at an interface between an electrolyte and an electrode. Due to the double-layer, the supercapacitor can store a much larger charge than the common capacitor. This supercapacitor can be a low-cost substitute for batteries in power tools, mobile electronic devices, and electric vehicles. Kim, Choi, and Lee developed a stretchable supercapacitor based on an electrolyte separator between first and second current collectors. This separator includes an elastic polymer layer such as styrene-b-butadiene-b-styrene (SBS), polyurethane, acrylate, or silicone polymers.
U.S. Patent 9,883,946 (Feb. 6, 2018), "Composite Prosthetic Surfaces," John Michael Pinneo, Roy McDonald, and Charles K. Lim (Sparkle Medical LLC, Portola Valley, Calif.)
Prosthetic joints are biomedical devices that replace bone and cartilage joints to restore, improve, or prolong function. These prosthetic joints need enhanced wear resistance for extended usefulness without needing a replacement. Pinneo, McDonald, and Lim developed a wear-resistant joint repair by filling a composite with hard particles. During wear, these particles are exposed, reducing wear and extending implant durability. Candidate matrix materials include metals (e.g., titanium or CoCr alloys), ceramics (e.g., alumina), and ultrahigh molecular weight polyethylene (UHMWPE) materials. Candidate filler materials include diamonds, silicon carbides, stainless steel, and titanium alloys.
U.S. Patent 9,884,955 (Feb. 6, 2018), "Hydroxylated-Fullerene-Containing Solution, Resin Molding and Resin Composition each using the Same and Method for Producing each of the Resin Molding and the Resin Composition,"Ken Kokubo, Takeshi Noguchi, Juichi Kasai, and Akio Harada (Total-Co, Ltd., Tokyo)
Nanofillers can be very useful because of their small size. However, dispersion remains a serious problem because of their tendency to aggregate and stick together. Kokubo et al. developed a hydroxylated fullerene filler in which a hydroxylated fullerene is uniformly dispersed in a solvent removable at low temperature. Fifty nm particles of hydroxylated-fullerene are dispersed in solvent of melted phenol or tetrahydrofuran/water solution. This dispersion mixes with a resin and the solvent removed, leaving a resin with uniformly dispersed hydroxyfullerene nanoparticles.
U.S. Patent 9,884,938 (Feb. 6, 2018), "Polymeric Plasticizer Compositions," Woo-Sung Bae, Rick Tabor, Kevin Anthony Rogers, and Shakti L. Mukerjee (Resinate Materials Group, Inc., Plymouth, Mich.)
Plasticizers increase plasticity, fluidity, or flexibility of materials such as plastics, clays, and concrete. Despite their utility, plasticizers are not always fully compatible and tend to leach out of their host reducing durability and reliability. Bae et al. developed a polymeric plasticizer made from an aromatic acid source, a glycol, and a C4-C35 monocarboxylic acid, ester or anhydride. The aromatic acid source can be obtained from recycled polyethylene terephthalate (PET). The plasticizer is formed by heating the components with catalysts and purifying by distillation. These polymeric plasticizers are useful for plasticizing thermosets and thermoplastics including polyvinyl chloride (PVC). The polymeric plasticizers provide a sustainable alternative to conventional phthalate ester plasticizers.
U.S. Patent 9,884,447 (Feb. 6, 2018), "Tools for Making Retroreflective Articles," Przemyslaw P. Markowicz (3M Innovative Properties Co., St. Paul, Minn.)
Retroreflective sheeting is used in road signs, pavement markers, license plates, and even reflective clothing. Retroreflective action is based on small surface cubic indentations shaped like the corner of a small cube. These retroreflective materials have a transparent planar front surface and a back-surface array of reflecting indentations. There is a need for improved tooling for retroreflective articles with weld lines that do not interfere with reflection. Markowicz developed a tool for producing patterned surfaces of microstructured retroreflective elements with welding seams less than 400 microns wide. A key factor in constructing the tool is the use of a phase shifting interferometer with a suitable objective lens to measure peak-to-valley optical path differences for individual cube corner elements.
U.S. Patent 9,884,439 (Feb. 6, 2018), "Method for Producing Foamed Molded Product," Satoshi Yamamoto, Atsushi Yusa, Hironori Ota, Tetsuya Ano, and Hideto Goto (Hitachi Maxell, Ltd., Osaka, Japan)
One approach to foaming is based on the release of pressurized fluid such as carbon dioxide foaming. However, obtaining and controlling carbon dioxide content in the melt before foaming is a problem. Yamamoto et al. developed a method for producing a foam-molded product based on a plasticizing cylinder having a high-pressure kneading zone and a pressure reduction zone. The pressure in each zone is controlled by screw rotation direction. One direction produces the high-pressure kneading zone and a reverse direction produces the low-pressure foaming zone. This enables precise control for effective and reproducible foaming. Candidate resins include thermoplastic resins from polypropylene to polyphenylene sulfide and composites from glass fiber, talc, and carbon fiber composites.
Reversible Crosslinking Agents
U.S. Patent 9,890,323 (Feb. 13, 2018), "Multifunctional Boronic Crosslinkers as Dual Viscosification and Friction Reducing Agents," Jeremy Holtsclaw, Ubong Inyang, and Dipti Singh (Halliburton Energy Services, Inc., Houston)
Many industrial applications like oil drilling require fluids that are thickened as needed but can unthicken as needed later. Holtsclaw, Inyang, and Singh developed treatment fluid for subterranean structures including water, a gelling agent, and a multifunctional boronic crosslinker. The multifunctional boronic crosslinker can thicken the materials as needed but can unthicken later as needed and re-thicken if necessary. The crosslinking agent was prepared using water-soluble monomer acrylamide and boronic acid in a ratio of boronic acid to water-soluble monomer of 1:3. The reversible crosslinking is based on pH of the fluids. These agents crosslink at pH 7.5 to 11 and un-crosslink at lower pH levels.
High Frequency Electronic Circuits
U.S. Patent 9,890,276 (Feb. 13, 2018), "Composite Material, High-Frequency Circuit Substrate made therefrom and Making Method thereof," Ming-She Su (Guangdong Shengyi Sci Tech Co., Ltd., China)
High-performance computers and communication equipment for transmitting and processing large amounts of information at high speeds require high-frequency structures. Su developed high-frequency circuits using liquid vinyl resins with polar functional groups and polyphenylene ether resins with molecular weights less than 5,000 containing terminal unsaturated double bonds, fiberglass cloth, powder filler, flame retardant, and cure initiator. The structures consist of prepregs covered with copper foils. The high-frequency circuit substrate made from the composite material has low dielectric constant, low dielectric loss tangent, and excellent heat resistance, and is convenient for process operation.
U.S. Patent 9,889,620 (Feb. 13, 2018), "Devices and Methods for the Production of Microfibers and Nanofibers," Stephen Kay, Thomas D. Carr, Carlos Barocio, and Joe Moore (Clarcor Inc., Franklin, Tenn.)
Electrospinning is a major manufacturing method to make nanofibers. However, it is difficult to produce large numbers of uniform fibers for precision applications. Kay et al. produced uniform microfibers and nanofibers by centrifugal forces rather than electrostatic forces. Polymer melts or solutions are injected into a spinning container with holes. The centrifugal force pushes the polymers through the holes forming very small fibers 1 micron to 50 cm long with circular, elliptical, or rectangular cross sections. Most polymers and composites can form reproducible uniform nanofibers or microfibers by this method.
ABOUT THE AUTHOR
Dr. Roger Corneliussen is Professor Emeritus of Materials Engineering of Drexel University in Philadelphia. He has been an SPE member since 1962 and an active member of the Philadelphia Section, serving as president and national councilman for several years. The above patents are selected from the 100 to 400 plastics-related patents found by reviewing 3,000 to 7,000 U.S. patents published each Tuesday. Readers can review the complete list of plastics-related patents by week at www.plasticspatents.com.
By Roger Corneliussen
|Printer friendly Cite/link Email Feedback|
|Date:||May 1, 2018|
|Previous Article:||Aurora Plastics Develops New Branding Strategy Following Strategic Acquisitions.|
|Next Article:||ENERGY-SAVING TIP: Power factor correction equipment.|