Tuesday, July 31, 2018

LIFE WOULD BE DIFFERENT WITHOUT NON-STICK COATINGS

Non-stick coatings are all around you, helping you do many of day-to-day things we all take for granted.
In this article we’ll take a look at how your daily life could be very different if non-stick coatings had never been discovered by Roy J. Plunkett in 1938.
BUMPIER CAR RIDES
Non-stick coatings are used in springs in a car’s suspension. Imagine having to drive over speed bumps with no proper suspension system in your car. It certainly would be a lot different to the smooth journeys you’re currently used to.
MORE UNCOMFORTABLE HOSPITAL BEDS
If you’ve ever had a stay in hospital, you may not have paid much attention to the ease of which the sides of your bed were put up and down. However, it would be much more difficult and annoying for everyone involved if they kept sticking and couldn’t be moved so freely and quickly.
It’s not just hospital bed frames that use non-stick coatings. The bed sheets are also treated with a substance that helps keep the mattress dry and patients cool.
YOUR FOOD COULD TASTE QUITE DIFFERENT
How many times have you bought a loaf of bread recently only to discover it’s all burnt at the bottom?
And how often do you tuck into scrambled eggs or a nice steak and have to pick out lots of little burnt bits as you eat?
One of the main applications of non-stick coatings is in food production, bakeware and cookware. Thanks to Mr. Plunkett you don’t have to have that lingering burnt taste every time you eat a sandwich at lunchtime or cook yourself a fry-up at the weekend.
HAVING TO WEAR CREASED CLOTHES
If there were no non-stick coatings, ironing clothes would be more of a problem. Burning them completely would be one option, or perhaps everyone would just be walking around quite happily in crushed, unkempt clothes.
THE DAILY NEWS WOULD BE MORE DIFFICULT TO READ
PTFE (a type of non-stick coating) is taken in scrap form and ground down for use in printing ink to make it flow better.
Can you imagine reading a newspaper where the ink had been getting stuck as it went through the presses?
YOUR CLOTHES COULD NEED WASHED MORE OFTEN
Non-stick coatings are also used to repel molecules from attaching to our clothes. While they’re not 100% efficient at this, your attire could be a lot messier without them and your washing pile at home would soon get out of control.
BAD NEWS FOR YOUR TEETH
Your dentist has probably told you on many occasions that flossing is good for your teeth in that it prevents cavities and decay. Dental floss also uses non-stick material to help it glide ffortlessly between your teeth.
POORER VISIBILITY WHEN DRIVING
Non-stick materials are also used on wiper blades. When the rain, sleet or snow is coming down fast, the last thing you want is your windscreen wiper blades sticking rather than wiping.
It’s not difficult to picture the consequences of poor driving visibility. You know that annoying noise and smearing that happens when your blades are on their last legs? That would be the norm without non-stick coatings.
UNSTABLE BUILDINGS AND BRIDGES
Buildings and bridges are subject to movement caused by high winds, temperature changes and even seismic activity. Non-stick coatings help make sure this movement is allowed for in a stable way via slide bearings so the things that have been constructed around us remain safe.
Without non-stick coatings, the man-made world around us would be more susceptible to damage, making it more dangerous and costly to maintain.
Tags:ptfe,coating

Wednesday, July 25, 2018

TEFLON® IN YOUR MAKEUP?

Teflon® in your makeup? Yuck. This non-stick ingredient and other fluorinated compounds have been associated with delayed menstruation, later breast development and cancer.
WHAT ARE FLUORINATED COMPOUNDS? Fluorinated compounds are ngredients built around the element fluorine, a halogen element, with properties similar to chlorine and bromine, which are common in flame retardant chemicals.
WHAT TO LOOK FOR ON THE LABEL: Polytetrafluoroethylene (PTFE), Polyperfluoromethylisopropyl Ether, DEA-C8-18 Perfluoroalkylethyl Phosphate, Teflon.
Fluorinated compounds are extremely stable and as a result do not break down in the environment. They have been found in remote regions of the world, including the polar ice caps.
Polytetrafluoroethylene (PTFE) appears to be the most common fluorinated compound in cosmetics. It is used most widely in anti-aging products and cosmetics, likely because it provides a smooth, sleek finish. PTFE is trademarked as Teflon®, for use in non-stick cookware.
PTFE is generated using another fluorinated compound, perfluorooctonoic acid (PFOA), which may leave residual amounts of PFOA in the final ingredient. The US EPA initiated the PFOA stewardship program to reduce PFOA residues in consumer products.4 While research suggests that most PFOA exposure results from its use in food contact items, indirect exposure from consumer products is also likely. PFOA in food contact materials may be as high as 300 ppb (in popcorn bags); but to our knowledge, no studies have yet assessed PFOA contamination in cosmetics containing PTFE. 
HEALTH CONCERNS: Potential contamination with perfluorooctonoic acid (PFOA) which is associated with cancer; mammary cancer; reproductive toxicity, endocrine disruption and environmental bioaccumulation and persistence. 
The International Agency for Research on Cancer reviewed the research on PTFE, and determined the current data was inconclusive with regard to PTFE’s potential to cause cancer. However, a wide-ranging literature has linked PFOA, which can be a contaminant of PTFE-containing consumer products, to health effects. In addition to the specific health effects from PFOA’s, researchers have found evidence that exposures to fluorinated compounds may increase the carcinogenicity of other chemicals when exposures occur together.
PFOA has been found in body fluid samples from 99.7 percent of the U.S. adults. Other studies have found PFOA in blood serum samples taken from adults from nine countries on four continents, and an additional study found PFOA in every one of the umbilical cord blood samples from newborns in Baltimore. Higher levels of the chemical in cord blood were associated with both lower birth weight and smaller size, indicating an effect of PFOA on prenatal development.
Cancer: The International Agency for Research on Cancer has designated PFOA as a possible carcinogen. Changes have been observed in mammary gland development in animals, which may have implications for breast cancer risk in exposed girls. The mammary gland may be especially sensitive to PFOA exposure, and both prenatal and early postnatal exposure may lead to concerning changes in mammary gland development.
One study found elevated levels of fluorinated compounds in Greenland Inuit women with breast cancer compared to Inuit women without breast cancer. A study of highly contaminated regions of Ohio and West Virginia found elevated levels of testicular, prostate, kidney and ovarian cancers and non-Hodgkin’s lymphoma among individuals with higher exposures to PFOA.
Endocrine Disruption: PFOA exerts effects on the endocrine system, disruptingestrogen receptors, thyroid receptors, steroid hormones, and male testosterone levels. Another study found further evidence that PFOA can act as an estrogen on its own, but this study also found that in the presence of the natural estrogen, estradiol, PFOA acted as an anti-estrogen.
Higher concentrations of PFOA and a related compound perfluorooctane sulfanate (PFOS) were associated with current thyroid disease among US adults.
Delayed Puberty: In southeastern Ohio, adolescent girls with higher levels of PFOA in their blood, were more likely to have delayed onset of menstruation. Another study of Ohio girls demonstrated that exposures to higher levels of PFOA were associated with later breast development. While earlier breast development is a known risk factor for breast cancer, these data support a potential endocrine-disrupting effect of PFOA, which may lead to other health effects later in life.
Reproductive Toxicity: PFOA is a known developmental toxicant. PFOA exposure in utero leads to reduced weight gain during lactation, delayed sexual maturation and death in rodents. In humans, PFOA exposure was associated with pregnancy-induced hypertension (high-blood pressure), and PFOS was associated with reduced birth-weight in full-term infants. Higher levels of the chemical in cord blood were associated with both lower birth weight and smaller size, indicating an effect of PFOA on prenatal development. In a novel study of PFOA exposures among pregnant women in an electronic waste recycling area in China, mothers living in the area had higher PFOA levels than mothers in other areas; and exposures were associated with delayed physical development and adverse birth outcomes. 
Other effects Both PFOA and PFOS have been associated with changes to the immune response, including inflammation. Research does not suggest an association between early life PFOA exposure and obesity in adulthoodor Type II diabetes. 
VULNERABLE POPULATIONS: Pregnant women, children
HOW TO AVOID: To avoid PFOA exposure from personal care products, skip products with polyperfluoromethylisopropyl ether, polytetrafluoroethylene, DEA-C8-18 perfluoroalkylethyl phosphate or Teflon® on the label.
REGULATIONS: PFOA: US EPA set a provisional health advisory for levels above .4 ppb in drinking water.

Monday, July 16, 2018

PTFE Shaft Seals: Meeting the Challenges of High Speed Applications

As you already know, speeds are a major factor in dynamic seal performance. In this blog post, we are going to discuss four ways that PTFE shaft seals work very well in high speed applications.

Where High-Speed Seals Are Found

High speed rotary shaft seals are found in many applications.  Examples would include cryogenic deflashing equipment, vacuum pumps, torpedo shaft seals, gas turbine engine starters, and submersible dredge pumps.  AC/DC motors often require high speed shaft seals, and can be found in items like CNC tool spindles and dental or surgical instruments.  

Smooth Operation

Another key issue with high speed seals is the need for smooth operation, which means avoiding problems like stick-slip.  PTFE is an ideal material for avoiding stick-slip, and supports smooth, quiet operation.

Friction

Friction can make or break a high-speed seal.  At high speeds, the effects of friction have a greater impact on seal performance.  Shaft seals need to have extremely low friction, and since some applications may prohibit the use of lubricants, there is a good chance that the ideal polymer material for a high-speed seal will be self-lubricating.  
PTFE is ideal for addressing this challenge because it has the lowest coefficient of friction of any material known to man, and is also self-lubricating.  

Elevated Temperatures

One of the main challenges in high speed shaft seals is controlling temperatures.  High speed leads to increased heat generation.  Heat generation leads to dimensional changes, which means that a high-speed seal needs to have a small coefficient of thermal expansion to ensure dimensional stability.  
Another goal is to conduct heat away from seal, which means that along with a small coefficient of thermal expansion the seal material needs to have a high coefficient of thermal conductivity.  Not all heat can be conducted away, however.  A high-speed seal needs to be made of a material that can handle higher temperatures.  
PTFE can perform well in temperatures up to 500°F.  It has good thermal conductivity which can be greatly improved using carbon fillers, and has a low coefficient of thermal expansion which can be enhanced through fillers such as glass and carbon.

Efficiency

As already mentioned, high speed shaft seals are often used with AC/DC motors.  These are often small and may be battery powered, making efficiency a very important factor.  If losses can be minimized, efficiency can be maximized and have a positive effect on battery life.  A low friction material that promotes smooth operation is vital for these types of applications, and PTFE certainly fits that bill.

Conclusion

High speed applications involve issues like the need smooth operation, performance and reliability at elevated temperatures, the necessity of very low friction, and the desire for maximum efficiency. Fortunately, there is a polymer material that can address all these issues:  PTFE.

Monday, July 9, 2018

PTFE and UHMW Choice for Non-stick Bearings and Bushings in Food & Dairy Industry


Food & Dairy Bearings and Bushings:

Bearings and bushings can be found in almost every step in food or dairy processing industries.  Polymers are a popular choice for bearings and bushings in the food and dairy industry, both at the design stage and when retrofitting.  Because they are greaseless, the can provide a more sanitary environment for food processing.  They don’t require the maintenance that metal bearings and bushings require, thus reducing downtime for maintenance.  Their durability results in longer mean times to failure.  They are usually much more resistant to corrosion and much less chemically reactive than metal bearings and bushings.  They also weight much less than equivalent metal bearings and bushings.

Non-stick Applications

These are all good reasons to use polymer bearings in the food and dairy industries, but what about situations where one of the design requirements is non-stick bearings?  That is not a problem at all. There are, in fact, two specific plastics that are commonly used in these situations:  PTFE and UHMW PE.

PTFE

PTFE, or Teflon, is well known for its anti-stick properties due to its use as a coating for cooking utensils.  In fact, even Geckos can’t hang on to PTFE.  PTFE is also hydrophobic.  It is usually known among engineers for having the lowest coefficient of friction any polymer or metal in existence.  It is also the least chemically reactive polymer, and has excellent wear properties.  It absorbs a minimal amount of moisture.  PTFE, in its virgin form, is odorless and tasteless.  It has FDA approval.

UMHW PE

UMHW (ultra-high molecular weight) PE (polyethylene) is known for its toughness, including the highest impact strength of any polymer currently available.  It has no moisture absorption. Its coefficient is low enough to be comparable to PTFE. More importantly, like Teflon, it provides a non-stick surface. It is often chosen because of its ability to resist material hang-up. Among its other properties is an abrasion resistance that is 10x that of carbon steel.  UMHW PE is tasteless, odorless, and nontoxic.  It has been approved by the FDA, USDA, Canada AG and 3A dairy.



Conclusion

If you are designing equipment for the food and dairy industry, or looking to retrofit existing equipment, and require non-stick bearings or bushings, look no further than PTFE and UHMW PE.

Tags:teflon ptfe,UHMW,food industry

Wednesday, July 4, 2018

5 Applications for PEEK in the Medical Device Industry

There are millions of medical devices that include components made from PEEK.  This usage has grown tremendously in the past fifteen years and is still evolving. In this post, we are going to look at typical applications for PEEK in the medical device industry, including both implantable devices and non-implantable devices.

#1 PEEK in Spinal Applications

A stiffness comparable to that of human bone, radiolucent properties, and reduced stress shielding are just a few of the features that make PEEK an excellent choice for spinal applications.
Spinal applications of PEEK include:
  • minimally invasive spinal implants
  • disc arthroplasty,
  • anterior cervical plates,
  • dynamic stabilization and motion preservation
  • interspinous spaces
  • posterior spine stabilization rods

#2 PEEK in Orthopedic Applications

Arthroplasty and arthroscopy have made extensive use of PEEK for several years, including knee and shoulder arthroscopy along with knee and hip arthroplasty. The implementation of PEEK in hip cups has been especially useful. PEEK works very well for knotless suture anchors in shoulder arthroscopy. Tibial screw anchors and sheaths made of PEEK provide excellent strength and far less failure.
Benefits of PEEK for orthopedic applications include:
  • improved stability
  • significantly better wear performance
  • and less need for revision

#3 PEEK in Trauma Applications

PEEK is also used in bone trauma applications such as fracture fixation plates and intramedullary (fracture fixation) nails.
The usage of PEEK in trauma applications results in outcomes such as:
  • improved healing rates
  • better pain relief
  • more straightforward MRI and CT imaging when compared to their metal counterparts

#4 PEEK in Dental Applications

PEEK is also used in precision, customized dentures and prosthetics that are an alternative to traditional metal dentures. They have been found to be far more comfortable, easier to tailor to a patient’s needs and an excellent fit for the modern CAM/CAD approach to dental prosthetics.

#5 PEEK in Non-Implantable Devices

Not all PEEK applications in the medical industry are for implantable devices. PEEK can be found in pumps, pistons, fluid transfer applications, and valves. PEEK seals and bearings are well established for use in critical medical and pharmaceutical applications such as dialysis, equipment, blood pumps, infusion pumps, reusable medical instruments, medical device fixtures, or tissue cutting tools.  

Why PEEK

In applications such as this, PEEK medical devices offer superior fatigue properties and low moisture absorption, which is critical in implantable devices. PEEK components are also more compatible with diagnostic imaging with no artifacts. Some grades of PEEK are radiolucent. Through fiber reinforcement, mechanical properties such as stiffness can be customized to meet application needs.It is possible to achieve a stiffness that approximates human bone using PEEK. Biocompatibility and biostability of load-bearing medical implants is another critical area in which PEEK excels. PEEK can also be manufactured using many different methods.

Conclusion

PEEK is used in many different areas of the medical industry, from implantable devices that have to be both strong and biocompatible to reusable medical instruments that have to be sterilized repeatedly using harsh processes such as autoclaving. PEEK is an good choice for medical applications for numerous reasons, including its excellent fatigue/wear properties, high strength-to-weight ratio, and biocompatibility.


Tags:peek,applications, polyetheretherketone

Monday, July 2, 2018

PTFE ELECTRICAL TAPE


The base material was made via fiberglass impregnation in PTFE and refined, coating with silicone adhesive and with excellent heat resistant and mechanical strength.
Good release and smooth
Good performance of high temperature keeping, stable size.
Small friction coefficient, good insulation.
Good corrosion resistance.
Applications
1. According to different thickness, can be using as many kinds of drying machine conveyor, bonding tape, sealing tape.
2. Using for welding cloth for plastic products welding, backing mat for plastic, film, hot sealing
3. Electrical insulation, mat, gasket, and so one.
4. Heat cladding layer, pack of heat insulation body.
5. Microwave mat,, oven chips, food drying.
6. Adhesive tape, hot transfer printing table cloths, and so on.
7. Backing cloth for pressure sensitive ahdesive.
8. Architectural membrance, many place of canopy, etc.
9. For various petrochemical pipeline corrosion resistant cladding, power plant emissions, environmental desulfurization.
10. A flexible compensator, the friction material, wheel slice.
11. After special processing, making "anti-static cloth.

Material: PTFEE ; Color: Brown ; Surface friction coefficient: 0.05~0.1 ; Insulating coefficient: >=1012 ohm ; Adhesion strength (to metal):  28N/100mm ; Tensile strength: 1700N/100mm ; Temperature resistance: -70-300°
Tags: PTFE Electrical Tape PTFE Tape

Sunday, July 1, 2018

Beginner’s Guide to PTFE and PEEK Backup Rings

Backup rings can be made from a variety of materials, including polymers. In this article, we will look at PTFE and PEEK backup ringswhile at the same time reviewing some of the basics of backup rings.

Why Use Backup Rings?

Rubber o-rings are good, but when temperatures and pressures rise they have a bad habit of extruding into clearance between mating surfaces, which isn’t a good thing. In fact, extrusion failure is one of the main causes of o-ring failure. As the o-ring begins to extrude into the clearance gap, it will experience more and more damage until it is useless. This phenomenon is sometimes called nibbling, and when it occurs you will notice that the o-ring will have a ragged edge on the low-pressure side.
Backup rings, also known as anti-extrusion rings, are used to keep o-rings from extruding into areas where they don’t belong. They are also used in conjunction with seals to either prevent damage to the seal or to control extrusion. Backup rings are made of an extrusion resistant, hard material. They fit between the o-ring (or seal) and the extrusion gap.

Where Should Backup Rings Be Used?

Backup rings are suggested for o-ring failures such as extrusion/nibbling (as we already discussed) and spiral failure (where cuts or splits spiral around the circumference of the o-ring). They should be used when temperatures or pressures are expected to reach a level that would cause the seal or o-ring to extrude. This could be continuous operating conditions or, as is quite common, pressure or
temperature spikes. Backup rings are also used when the design requires a large extrusion gap.
Note that when used with seals, backup rings are usually placed downstream of the seal gland.
Finally, backup rings can be used in both static and dynamic applications.

What Kinds of Materials Are Used for Backup Rings?

Two of the most common materials used for backup rings are PTFE and PEEK. Both PTFE and PEEK are far less likely to extrude than the elastomers used for seals and o-rings. This means they can retain their shape even in the presence of elevated temperatures, high pressures, and aggressive chemicals. This allows them to hold the o-ring or seal in place.
Both PEEK backup rings and PTFE backup rings are usually filled, meaning they have a filler material such as glass or carbon fiber added to increase their compressive strength and dimensional stability.  Another benefit of using PEEK and PTFE for backup rings lies in their chemical resistivity, making them ideal for chemically aggressive environments. They also have low friction and relatively high continuous operating temperatures.

Conclusion

PTFE and PEEK are popular choices for backup rings because they are dimensionally stable, chemically resistant, have excellent compressive strength, and function well even at elevated temperatures and pressures. As an anti-extrusion device, they work extremely well with both o-rings and seals to prevent extrusion in situations that involve large clearances, high temperatures, and high pressures. If you are experiencing extrusion issues, don’t forget to consider a backup ring!
Tags:teflon ptfe,ptfe,peek,rings