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In this article, the author presents a comparative studies of the heat deflection temperature and dynamic mechanical analysis (DMA). It is stated that the presentation of DMA, data could frustrate users and discourage its adoption. Several figures illustrating full scope of temperature from a DMA temperature scan, linear plot of the elastic modulus versus temperature are also presented. According to the author, plastics are viscoelastic and behave both like an elastic solid and a viscous fluid.

The article discusses the advantages of artificial tears based on hyaluronic acid (HA) formulations compared to other compounds. Tear substitutes are used in the treatment of dry-eye disease. While there are numerous over-the-counter artificial tear products, they provide momentary relief and require frequent applications. HA has viscoelastic properties and is a polysaccharide naturally present in humans and some animals. They are said to provide better tear stability and longer retention time.

The article discusses the engineering practice of replacing industrial fasteners with multi-function structural adhesives. Examples of structural adhesives include epoxies and acrylic foam tapes. Adhesives must be resistance to corrosion, humidity, and chemical exposure. A number also often benefit from high viscoelasticity.

The article discusses the importance of time and temperature when considering a polymer for single-point application. It mentions the characteristics of strains and stresses when the load is applied or if a load is maintained for a period of time. It discusses the challenges related to the viscoelastic behavior as it affects time and temperature.

The article presents the advantages of finite-element analysis (FEA) in comparing common sealing polymers. FEA considers the viscoelasticity of elastomers and plastics which primarily based on the creep and stress relaxation that affect the shape, deformation and performance of the material. Moreover, FEA allows engineers study the viscoelastic effects of elastomers to identify its performance, sustainability and capability.

The article discusses research on the effects of temperature on the properties of polymers. Topics mentioned include a comparison of tensile stress-strain behavior for an acetal copolymer, glass-filed polypropylene, and glass fiber-reinforced nylon 66, the significance of the principle of viscoelasticity, and strain-rate dependence of polymers.

The article discusses the use of liquid and viscoelastic adhesives for adhesive-based assembly of low-surface energy (LSE) plastics. It claims that the use of liquid adhesive results in stronger chemical and mechanical bonds. It notes that the use of liquid and viscoelastic adhesives creates strong bonds with LSE plastics resisting impact, shock, and fatigue.

The article tackles the five critical factors needed in ensuring plastics performance during engineering design. It is noted that failure to understand the complexities of plastics can result to poor performance. These factors are viscoelasticity, special design considerations, impact of reinforcements and other additives, effects of manufacturing and field conditions.

The article focuses on the benefits of using the tri-soft shell technique (TSST) by surgeon to perform different maneuvers in adjacent spaces. Medical doctor Steve A. Arschinoff mentions that the combination of all soft-shell techniques into a general tri-soft shell can simplify surgery and make it procedurally more reliable and consistent. It states that the dispersive opthalmic viscosurgical devices (OVDs) protects the endothelium in the TSST.

This article presents information on new products related to mechanical engineering developed in the U.S. The new sealed cell available from ATS RheoSystems/Reologica Instruments was designed to be application-specific for the measurement of viscoelastic rheological properties of solutions above their boiling point without loss of any volatile components. The Series 881 vacuum hose reel developed by Nederman Inc., provides a practical solution for hose storage. Suitable for use with central or portable high vacuum systems, the new reel complements Nederman's line of industrial vacuum systems. Keystone Electronics Corp.'s low-profile TO-3 power transistor sockets are designed to aid installation of Jedec TO-3 MPM power transistors, by eliminating the need to use insulated bushings.

The article reports on the viscosity behavior of bitumen and its blends with diluent at different temperatures and how to improve measurement of heavy oil viscosity. It also determines simulations for prediction of viscosity of the blend. A viscometer is used at three different temperatures to measure the viscosities of the bitumen and blend.

The article reports on the development of a nanotube rubber which maintains its viscoelasticity in extreme temperatures. The carbon nanotube (CNT)-based material may have applications in vehicles that travel to the cold reaches of interstellar space and inside high-vacuum furnaces. The material was created using a combination of water-assisted chemical vapor deposition, reactive ion etching of the catalyst film used in the nanotubes, and compression.

The article reports on the Resonant Tube Viscosity Sensing Device manufactured by Integrated Sensing Systems Inc. It has been granted the patent of Microelectromechanical Systems sensor, which measures viscosity, density, temperature and mass flow of motor oil. It also shows the need for an oil change. The sensor consists of a micromachined tube made of silicon, quartz, or glass.

Provides information on new technologies for viscoelastic flexible urethane foams. Development of the Bayfit Memory VE-PUR foam formulations from Bayer MaterialScience; Replacement of waterproof coverings of polyvinyl chloride; Application of Baytec Reaktiv elastomer coating.

This article focuses on viscoelastics. The current preferred term of viscoelastics is optical variable devices (OVDs), which stand out as one of the most significant advances in the history of cataract surgery. They are composed of hyaluronic acid, chondroitin sulfate, or hydroxypropyl methylcellulose and vary in molecular weight, concentration, and chain length. Variations in these parameters will affect the intraoperative behavior of OVDs, leading to changes in viscosity, elasticity, rigidity, and pseudoplasticity.

This article reports that Healon 5, used with the Sovereign cataract extraction system with WhiteStar technology by Advanced Medical Optics Inc., can improve the odds of success in problematic situations where complete control of the anterior chamber is critical, according to ophthalmologist Randall Olson at the University of Utah School of Medicine, Salt Lake City. Sovereign with White Star is the industry leader in short pulses of energy that more efficiently remove nuclear material by emphasizing transient cavitation. It also improves safety by improving followability, the nuclear material stays at the tip, which means one don't have to chase it and energy is not wasted.

Reports on the availability of the Ciba Vision's AQuify Long-Lasting Comfort Drops for contact lens wearers in the United States and Canada. Benefit of the viscoelastic substance called hyaluronate in the solution.

Studies the pars plana injection of viscoelastic for managing posteriorly dislocated IOL in San Francisco, California. Cause for delayed, spontaneous posterior dislocation of posterior chamber; Inclusion of trauma and YAG capsulotomy; Observation of posterior dislocation of the IOL.

Analyzes the behavior of viscoelastic materials. Factors that determine the degree of viscoelastic response; Use of mechanical analogies in modeling viscoelastic behavior; Ways of confirming the model data for mechanical-analog models.

This article presents information on a newly developed orthopedic mattress, named "Calgero," introduced by the French company, La Belle Co. The device comes in two slightly different versions. One, Calergo 2, has an inflatable underlying envelope. Another, Calergo 3, has a second inflatable envelope between the patient and the depressurizable envelope. Both can be used as cushions to provide automatic redistribution of a patient's weight, and thus prevent bed sores. The envelope's granular material has enough viscoelasticity to he molded by hand into almost any desired shape. After molding it, the envelope of this mattress can be depressurized by applying a vacuum pump to a built-in valve. It will then retain its molded shape and exhibit both greater rigidity and improved load-bearing capacity.