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Shape Memory Clamps

U.S. Patent 9,222,007 (December 29, 2015), “Shape Memory Polymer Which Functions as a Dry Adhesive Clamp and Methods of Making and Using the Same,” Tao Xie and Chen-Shih Wang (GM Global Technology Operations LLC, Detroit, Michigan, USA).

Temporary adhesives that are simple and reliable to use over and over again are useful in many manufacturing operations for temporary clamping. Xie and Wang developed a shape memory polymer which functions as a temporary clamp based on an aliphatic diepoxy and a diamine curing agent.

The material is shaped as needed and applied hot to temporarily hold structures together. As it cools down, the combination of shape and adhesive clamps the structures together. Its glass transition temperature ranges from 30 to 200°C, and it’s rigid at room temperature. When heated above the glass transition temperature it loses its adhesive character and the structure returns to its original shape, releasing the clamping. This material is reversible and can be reused for clamping as needed.

Overmolded Golf Tees

U.S. Patent 9,216,337 (December 22, 2015), “Overmolded Golf Tee and Method of Making It,” Francis Carroll and James Carroll, Jr. (Green Keepers, Inc., Philadelphia, Pennsylvania, USA).

Golf tees are typically made of a rigid material such as wood or hard plastic, with a cup-shaped crown for holding the golf ball. But the traditional cup with a continuous lip causes friction, affecting the path of the ball. It would be desirable to reduce that friction. 

Carroll and Carroll, Jr. developed a golf tee consisting of a rigid stake topped by overmolding a softer, flexible crown. The crown and the stake can have projections or points rather than continuous edges or surfaces. Stake projections provide a stronger bond with the crown. The stake can be a rigid nylon and the overmolded crown a flexible elastomer, such as low-density polyethylene or thermoplastic urethane. The ball rests on small protrusions extended from the crown.

An Improved Polypropylene

U.S. Patent 9,221,931 (December 29, 2015), “Method for Producing Polypropylene Material, and Polypropylene Mate- rial,” Akira Nakasuga and Hironori Tabata (Sekisui Chemical Co., Ltd., Osaka, Japan).

Polypropylene (PP) materials are strong and tough with good heat resistance. However, new applications require even higher strength and better heat resistance. Both properties can be improved with molecular orientation and crystallization. 

Nakasuga and Tabata produced a better PP sheet by rolling a sheet just above the melting temperature (T_m) of the unrolled PP. This material is then held to a temperature between 10 and 20°C below T_m. 

The crystallinity of the material before this treatment is 40%, and after the heat treatment it’s at least 55%. The melting temperature before rolling is 165°C, and over 170°C after the heat treatment.

Reactive Fluoropolymer Powders

U.S. Patent 9,221,926 (December 29, 2015), “Expandable Functional TFE Copolymer Fine Powder, the Expandable Functional Products Obtained Therefrom and Reaction of the Expanded Products,” Ping Xu, Jack J. Hegenbarth, and Xin Kang Chen (W. L. Gore & Associates, Inc., Newark, Delaware, USA).

Polytetrafluoroethylene (PTFE) materials have a unique combination of chemical resistance, thermal stability, and low surface energy, with excellent electrical and dielectric properties. Poor creep resistance and ionizing radiation resistance can be improved by stretching. However, there’s a need for fluoropolymer materials with enhanced chemical reactivity. 

Xu, Hegenbarth, and Chen developed a functional TFE copolymer fine powder containing 0.001 to 10 mol% co-monomers with acid groups such as carboxylic, sulfonic, or phosphoric acids pendant to the polymer chain. The functional TFE copolymer fine powder resin is paste-extrudable and expandable, and may further react as needed after expansion. 

HDPE Pumping Stations

U.S. Patent 9,217,244 (December 22, 2015), “Portable Steel-Reinforced HDPE Pump Station,” Daniel M. Early and Scott F. Easter (Appalachian Technology Solutions, LLC, Roanoke, Virginia, USA).

Pump stations are used to pump wastewater from one location to another. Conventional pump stations consist of steel and concrete structures. However, wastewater is an aggressive corrosive because of sulfuric acid-like materials that are often present. 

Early and Easter developed a portable steel-reinforced HDPE pump station. It consists of a vertically upright, cylindrical wet well structure fabricated from HDPE reinforced by helically wound steel ribs containing the pumps and pipes. Exterior foam insulation or thin HDPE shells can enclose the outer portions of the well. HDPE materials form other structures for reducing corrosion, such as piping consisting of HDPE encapsulating steel spiral-ribbed banding. The HDPE material is the key barrier to corrosion.

Long Fiber-Reinforced Plastics

U.S. Patent 9,217,079 (December 22, 2015), “Long Fiber- Reinforced Thermoplastic Resin Composition Having Improved Impact Resistance and Molded Article Using the Same,” Chang Wan Son, Hyeon Don Kim, Eun Seon Jeon, Yong Chun, Ha Kyu Seo, Seung Hyun Lee, and Woong Jae Boo (Hyundai Mobis Co., Ltd., and GS Caltex Corp., Seoul, South Korea).

Automotive interior parts such as soft crash pads are based on resins and fibers with softness along with impact protection. These materials must show impact resistance, chemical resistance, and moldability, as well as reduced thickness. And they must be lightweight. 

Son et al. developed long fiber-reinforced thermoplastic resins with improved impact resistance, including 10-20 wt% long fibers, 50-77 wt% ethylene-propylene copolymer, 10-36 wt% thermoplastic elastomers, 0.05-7 wt% functional group-grafted modified polypropylene resin, and 0.5-5 wt% inorganic filler. Candidate fibers include glass, carbon, polymer, basalt, natural, and metal fibers.

Blowing and Filling Containers

U.S. Patent 9,216,537 (December 22, 2015), “Compensation for Hydrapak Machine using Isolator Cylinder,” Brad Wilson, Kirk Edward Maki, and George David Lisch (Discma AG, Hunenberg, Switzerland).

As a result of environmental and other concerns, lightweight polyethylene terephthalate (PET) containers are now being used more than ever to package numerous commodities previously supplied in glass containers. Traditionally, blow molding and container filling were developed as two independent processes. In many cases these steps are carried out by different companies. Attempts are being made to combine blowing and filling in one step for efficiency and cost reduction. 

Wilson, Maki, and Lisch developed a system for simultaneously forming and filling a plastic container. A pre-form is inserted into a mold, and the liquid product is used to pressure and expand the preform and complete the expansion. After expanding, the liquid remains within the container as the end product. 

Hydroforming Composites

U.S. Patent 9,216,523 (December 22, 2015), “Process for Shaping or Forming Articles,” Gregory M. Monforte, II, David James Burke, and Matthew Madden (Gentex Corp., Simpson, Pennsylvania, USA).

Hydroforming uses high-pressure hydraulic fluid to compress a working material against a stationary die or moving punch to shape an article. Hydroforming applies normal, isostatic pressure to all points along the surface of the working material. 

Monforte, II, Burke, and Madden shaped a composite with two stages: (a) consolidating and shaping the working material into a pre-form shape using a dynamic hydroforming process with a rigid, male-shaped tool and a non-rigid, female-shaped tool without heating, and (b) further consolidating and shaping the working material into the final shape using a rigid forming tool with heating. 

One product example for this process is a helmet for pilots and military personnel. The working material consists of multiple pre-impregnated sheets of composite fibers.