polymerguru

Today's KNOWLEDGE Share: The frozen skin that develops during fill will barely subsequently shrink, since it is already solid ! As a consequence, thin parts, where the frozen skin represents a significant fraction of the thickness, will shrink way less than thick parts where frozen skin is a negligible fraction of total thickness! Note that since frozen skin is highly fill-rate dependent, when filling slowly you will observe less shrinkage, hence less need for pack. The IMFLUX process (low pressure molding) does indeed claim essentially no need for a pack. While this is true, please note that filling as slowly as possible (near 100% frozen skin at end of fill, just before risking a short-shot) means that you will produce VERY ORIENTED plastic parts with : - very high birefringence (amorphous) - very anisotropic mechanical properties (semi-crystalline). Many technical parts would rather benefit from low molecular orientation and maximum isotropy of performance, hence a faster fill f

Today's KNOWLEDGE Share: The Injection Molder’s Most Important Job What is the most important job of the injection molder? Ask people in the plastics industry, and you will get a variety of answers. ·  Produce parts to the part drawing dimensions. ·  Keep the supply chain fed with parts. ·  Produce parts at low cost. ·  Parts with acceptable cosmetic appearance. As significant as these functions are, I believe the most important and fundamental role of the injection molder is to protect the integrity of the plastic material. A particular resin was chosen for a part for a reason – because it satisfied the requirements of the application. The injection molding process can have deleterious effects on the properties of the molded part material – mechanical, thermal, chemical, electrical, environmental, and physical. Injection molding is a very complicated manufacturing process. Some plastics industry leaders suggest forming plastic parts through injection molding is the most difficult

  Today's KNOWLEDGE Share: Types of HYDROGEN: Low carbon hydrogen from water electrolysis using renewable power: green Low carbon  #hydrogen  from water electrolysis using nuclear power: pink Low carbon hydrogen from natural gas using reforming with  #CCS : blue Low carbon hydrogen from coal  #gasification  with CCS: purple Low carbon hydrogen from  #naturalgas  pyrolysis and solid carbon production: turquoise Visit MY BLOG  https://lnkd.in/fcSeK9e #hydrogeneconomy   #hydrogen   #greenhydrogen   #bluehydrogen

Using ultrasonic waves that propel drug molecules into the skin, the patch could be used to treat a variety of skin conditions. The skin is an appealing route for drug delivery because it allows drugs to go directly to the site where they’re needed, which could be useful for wound healing, pain relief, or other medical and cosmetic applications. However, delivering drugs through the skin is difficult because the tough outer layer of the skin prevents most small molecules from passing through it. In hopes of making it easier to deliver drugs through the skin, MIT researchers have developed a wearable patch that applies painless ultrasonic waves to the skin, creating tiny channels that drugs can pass through. This approach could lend itself to delivery of treatments for a variety of skin conditions, and could also be adapted to deliver hormones, muscle relaxants, and other drugs, the researchers say. “The ease-of-use and high-repeatability offered by this system provides a game-changing

Today's KNOWLEDGE Share: Yellowing of Polycarbonate Because of the molecular structure of polycarbonate, the polymer is susceptible to yellowing through a variety of degradation mechanisms. Discoloration of polycarbonate can occur through oxidation, either during processing or as a result of elevated temperature exposure in air. Yellowing can also take place through sterilization, such as autoclaving, radiation, or ethylene oxide. Further, polycarbonate is highly susceptible to yellowing through ultraviolet radiation (UV) exposure. When polycarbonate is exposed to ultraviolet radiation as sunlight, yellowing can take place rapidly. This discoloration is principally a surface phenomenon, approximately 25 micrometers deep, due to the penetration depth of the UV radiation into the polycarbonate.   Yellowing within polycarbonate occurs as a result of the formation of degradation breakdown products that absorb in the yellow range of the visible light spectrum. This includes substituted

Today's KNOWLEDGE Share: Lightning damages the fuselage of a Boeing 787-9!  An American Airlines Boeing 787 Dreamliner needs repairs after a lightning strike significantly damaged its fuselage. The incident happened Monday, February 20th, when N839AA, a 787-9, was traveling from Tokyo to Dallas/Fort Worth. The aircraft is reportedly being worked on to be restored back to operational condition!  Despite a strong and thick fuselage, the 787 reportedly has a known issue with lightning strikes. In 2019, Boeing reduced lightning protection in the wings of some 787s to reduce costs and speed up deliveries, but the company reportedly said that safety was not compromised. In May, a Jetstar 787 was grounded after sustaining extensive damage from a lightning strike. Source: Simpleflying/ #managingcomposites #thenativelab Visit MY BLOG http://polymerguru.blogspot.com #aerospace # #aircraft #airlines #boeing #safety #composites #boeing787