polymerguru

  𝐓𝐨𝐝𝐚𝐲'𝐬 𝐊𝐍𝐎𝐖𝐋𝐄𝐃𝐆𝐄 𝐒𝐡𝐚𝐫𝐞 🟢 𝐖𝐡𝐚𝐭 𝐀𝐫𝐞 𝐁𝐮𝐫𝐧 𝐌𝐚𝐫𝐤𝐬 𝐈𝐧 𝐈𝐧𝐣𝐞𝐜𝐭𝐢𝐨𝐧 𝐌𝐨𝐥𝐝𝐢𝐧𝐠? 𝐖𝐡𝐲?🟢 When we are doing molds trials and normally you will find some plastic parts with burn mark. Here share some information about this defect. Burn marks refer to dark or black marks formed at the end of the flow path or in trapped gas areas during the injection molding process due to poor mold venting or too fast injection, where the air inside the mold does not have time to escape and suddenly heats up under high pressure (in extreme cases, temperatures can reach up to 3000 degrees). The overheated compressed air scorches the melt. 🟢 Why? Here are 3 reason for your reference 🟢 1. Poor mold venting causes the trapped gas to be compressed and overheated. 2. Excessive melt temperature or injection speed. 3. The material remains in the barrel for too long, leading to overheating source : Michael Qu #plastics #injectionmolding #injectionmold

On Wednesday, fiberglass producer China Jushi, a subsidiary of China National Building Material Group( #CNBM ), opened a new production line in Huai'an, Jiangsu province, capable of producing 100,000 metric tons of electronic-grade #fiberglass and 390 million meters of electronic fabric annually. This line represents 9 percent of the global market capacity, making it the largest of its kind worldwide. Zhou Yuxian, chairman of CNBM, highlighted that this line is a crucial component of the world's first zero-carbon fiberglass smart manufacturing base, set to supply high-end electronic materials for industries like consumer electronics, 5G, and medical technology. General manager Yang Guoming of China Jushi said that the new capacity will be gradually released to stabilize the electronic fabric market. He said that price volatility poses challenges, but the company plans to adjust prices based on market demand and feedback from industry partners. With the rapid growth of the elec...

As #Boeing777 -8 freighter, which has won 68 orders from customers worldwide, is being built at Boeing’s 777/777X final assembly facility in Everett, Washington, employees express their pride and hopes, and talk about their approach. The teams work on the ‘wing-body join,’ i.e. they bring the 777-8F’s mid-fuselage together with its composite wings, which span 235 feet (72 metres), i.e. about twice the distance of the Wright brother’s first flight! This is something to be proud of,” says Landa. “It’s a whole new freighter that our customers are excited about, and we’re excited to be building something brand new,” says assembly installer Pedro Landa. Then, the teams begin outfitting forward and aft fuselage sections with systems and wiring. “We’re building on the success of the legacy 777 Freighter,” explains Jens Biemann, design engineer lead. “This is going to be an airplane that will help customers be successful in their businesses. Building a new airplane is challenging, from coordin...

U.S. production of major plastic resins totaled 8.2 billion pounds during February 2026, a decrease of 7.8 percent compared to the prior month, and an increase of 2.7 percent compared to the same month in 2025, according to statistics released today by the #AmericanChemistryCouncil (ACC). Year-to-date production was 17.1 billion pounds, a 5.0 percent increase as compared to the same period in 2025.  Sales and captive (internal) use of major plastic resins totaled 8.1 billion pounds during February 2026, a 5.6 percent decrease compared to the prior month, and an increase of 0.7 percent from the same month one year earlier. Year-to-date sales and captive use were 16.6 billion pounds, a 1.9 percent increase as compared to the same period in 2025.  source : ACC

Dow today announced a step-change in #highvoltagedirectcurrent (HVDC) insulation systems with the latest addition to its #ENDURANCE™ Compounds for Cable Systems portfolio – a fully qualified 525 kV HVDC insulation system engineered for the demands of modern power infrastructure. HVDC has emerged as the preferred technology for long-distance electricity transmission, offering lower transmission losses and greater suitability for modern grid architectures as electricity networks evolve to integrate renewable energy and transport power across longer distances and national borders. Fully cross‑linked, fully qualified system design ENDURANCE™ Compounds for Cable Systems bring together insulation and semiconductive #crosslinkedpolyethylene (XLPE) into a high‑voltage direct current (HVDC) insulation system – purpose-built for the performance demands of the expanding offshore wind infrastructure and long-distance interconnector projects. The system combines ENDURANCE™ HFDB‑4401 UDC, a fu...

Today's KNOWLEDGE Share Scientists discover liquids can fracture like solids under extreme stress Researchers from Drexel University have discovered that liquids can, it appears, fracture like solids under specific conditions. In a discovery that could shift our understanding of fluid mechanics, it now appears that viscous fluids can suddenly break when stretched with enough force. Unlike solids, which will stretch and eventually snap, liquids have never been believed to have a breaking point. This new research, however, appears to challenge this belief. “Our findings show that if pulled apart with enough force per area, a simple liquid — a liquid that flows — will reach what we call a point of ‘critical stress,’ when it will actually fracture like a solid,” said Thamires Lima, Ph.D., an assistant research professor in Drexel’s College of Engineering, who helped to lead the research. Interestingly, the team also found that the liquid “snapping” produces a sudden noise, like that of...

  𝐓𝐨𝐝𝐚𝐲'𝐬 𝐊𝐍𝐎𝐖𝐋𝐄𝐃𝐆𝐄 𝐒𝐡𝐚𝐫𝐞 𝐁𝐢𝐠 𝐦𝐨𝐥𝐝, 𝐬𝐦𝐚𝐥𝐥 𝐬𝐡𝐨𝐭? 𝐇𝐞𝐫𝐞’𝐬 𝐰𝐡𝐚𝐭 𝐭𝐨 𝐝𝐨. This is a situation I run into often: a mold has a large footprint but produces relatively small parts. The projected area is big, but the shot weight is low. And suddenly, machine sizing becomes more complicated than just matching tonnage or volume. In cases like this, it’s easy to make the wrong trade-off. You might pick a smaller press for the injection volume, but then fight mold deflection or risk flash due to underclamping. Or you oversize the clamp to handle the mold size and end up with an injection unit that’s too big, causing short shots, overshear, or unstable back pressure. This is where proper application engineering matters. Because the solution isn’t always obvious. It could be: - A machine with a larger platen but lower tonnage - A tie-bar-less machine to fit the mold with better support - A different screw design to keep velocity and back pressure sta...