polymerguru

Today's KNOWLEDGE Share: EV BATTERY: Although lithium-ion batteries have high energy density and cycle life, the cost and safety of the batteries limit their widespread use in this field. Sodium-ion batteries not only have high safety and cycle life, but also have obvious advantages over lead-acid batteries in terms of energy density, making them a good alternative to lead-acid batteries in the field of low-speed electric vehicles. In the low-speed vehicle market, sodium-ion batteries are cost-effective and competitive. The low-speed vehicle market does not require high energy density and the performance of sodium-ion batteries is sufficient to meet the needs of low-speed electric vehicles. After determining the standard for miniature low-speed pure electric passenger vehicles, the majority of car companies have clear goals, and they have tried to slice the cake in the low-speed electric market and launched low-priced A00-class electric vehicles. Beginning in July 2020, China has o...

Today's KNOWLEDGE Share: How composite materials helped to enable the Mongols military dominance during the 13th century?  The use of composite materials in military equipment started much earlier than you think!  In about 1200 AD, Mongols invented the first composite bows made from a combination of wood, bamboo, bone, cattle tendons, horns, and silk bonded with natural pine resin. These small, powerful and extremely accurate bows were the most feared weapons on earth until the 14th century invention of effective firearms.  Composite Mongolian bows helped to ensure Genghis Khan's military dominance during that period, in which its arsenal conquered huge chunks of central Asia and China!  History shows us how the mastery of advanced materials has been extremely important, even for ancient civilizations!  Source: #managingcomposites #thenativelab Visit MY BLOG http://polymerguru.blogspot.com #composites #bow #military #mongolia #china #asia

Today's KNOWLEDGE Share: 21st century concrete : composite metamaterial with super compressibility, energy harvesting! "A new study introduces the use of metamaterials in the creation of concrete, making it possible for the material to be specifically designed and tailored in its attributes such as load-bearing capability, flexibility and shapeability. These can be fine-tuned in the creation of the material, enabling builders to use less material without sacrificing strength or durability."  “This project presents the first composite metamaterial concrete with super compressibility and energy harvesting capability,” said Alavi. “Such lightweight and mechanically tunable concrete systems can open a door to the use of concrete in various applications such as shock absorbing engineered materials at airports to help slow runaway planes or seismic isolation systems.”  "The material is also capable of generating electricity — not enough to send power to the electrical grid...

Today's KNOWLEDGE Share: How does crystallization kinetics possibly influence the PvT data we use in all our molding simulations ? PvT are typically obtained, in theory, under "thermodynamic equilibrium" conditions. This means at speed so low that kinetics should be irrelevant. The molding process is the complete opposite ! Very fast cooling will shift crystallization T to lower values. And, as also depicted in the figure, the solid state density will be lower (so specific volume, the Y axis, higher for the red curve). Implementing crystallization kinetics in Flow Simulation is therefore quite a big challenge since cooling rate will be different from part to part, molding condition to molding condition, as well as within the same part (thin vs. thicker areas cool at different rates for instance and temperatures are different throughout the melt). People who have attempted to implement such "dynamic PvT" or "fast PvT" often neglect to account for the e...

Today's KNOWLEDGE Share: Natural Fiber Composites: Composite materials have found applications in virtually all markets, from bathtubs to spaceships. In some markets, composites are still the newcomer, while in others, the hard-earned reputation of composites is well established. Across their varied applications, composites are commonly chosen because they are considered “high-performance” materials. In the materials industry, earning the title of “high-performance” typically demands high strength, high stiffness, and low weight. We combine these attributes when we examine the specific properties, or the strength-to-weight and stiffness-to-weight performance of the material. The higher the specific properties, the more demanding applications we can expect to address. In recent years, consumers have begun to demand not only high performance, but also improved sustainability and reduced environmental impact. We believe the material champions of the future will combine high specific p...

Today's KNOWLEDGE share: BAMBOO FIBER: Bamboo fiber yarn is a type of cellulose fiber extracted from the natural growth of bamboo and is the fifth natural fiber after cotton, hemp, wool, and silk. Bamboo fiber yarn has good breathability, instant water absorption, strong wear resistance, and good dyeing properties. It also has natural antibacterial, bacteriostatic, mite removal, odor resistance, and UV resistance functions. Bamboo fiber yarn textile products are highly favored by consumers due to their inherent properties, and the demand for these products continues to increase each year. THE COMPOSITION OF BAMBOO FIBER The chemical composition of bamboo fiber, also known as bamboo viscose, mainly consists of cellulose, hemicellulose, and lignin, all of which are polysaccharides and account for over 90% of the dry weight of the fiber. The other components include proteins, fats, pectin, tannins, pigments, and ash, most of which are located in the ...