Better than PTFE and UHMWPE: New PA6 and UHMWPE Compound Optimizes Bridge Bearing Propertie

Plastics distributor Dreyplas and Spanish company Mekano4 (MK4), a specialist in technical solutions for bridge bearings and post-tensioning, have jointly developed MKSM® a thermoplastic sliding material. It combines excellent wear resistance with heat distortion temperature higher than 80ºC and a very low coefficient of friction. Mitsui Chemicals supplies the base polymers for this innovative alloy of PA6 with UHMWPE plus special additives, which has been patented for this application.

MK4’s structural bearings are in widespread use in construction and civil engineering, especially in bridges. MKSM transfers very high static loads in bridges, where its outstanding sliding behavior facilitates displacements and, in the case of curved sliding elements, also a limited degree of rotation in all axes between the bearing-mounted elements and the base structure. Compared to semi-finished product UHMWPE and PTFE, this new sliding material offers enhanced thermal properties, abrasion and heat distortion resistance. Its longer service life, compressive strength, and lower sliding friction can make it possible to use smaller sliding bearings. It can also replace fluoropolymers such as PTFE, which are currently the focus of controversy.

The base sheet with a thickness of 8 mm ± 0.2 mm is manufactured on a horizontal calender-extruder system by the fabricator SIMONA, in Kirn, Germany. MK4 produces the finished product by cutting the sliding bearing sheets to size and drilling recesses for oil lubrication.

As Dreyplas’ Marketing Director Norbert Hodrius explains, “Where particular requirements have previously meant that there were no alternatives to using fluoropolymers such as PTFE, PVDF etc., this high-performance compound, which is now part of our portfolio, offers advantageous solutions in many cases. Developing special UHMWPE-based compounds of this kind is just one of the services we offer our customers. Our many years of experience and close cooperation with Mitsui Chemicals mean we can use our development and materials expertise to bring products with real added value to market in a short time, as in this joint project with Mekano4.”

source:Dreyplas/konsens.de

Today's KNOWLEDGE Share:NREL Builds and Tests Wind Turbine Blade With Recyclable Resin:

Today's KNOWLEDGE Share

NREL Builds and Tests Wind Turbine Blade With Recyclable Resin:

Researchers at the Department of Energy’s National Renewable Energy Laboratory (NREL) published a paper in the journal Science describing the manufacture and testing of a composite wind turbine blade using a resin that is chemically recyclable and made from materials that can be bio-derived.

The new resin, nicknamed PECAN (polyester covalently adaptable network) performs on par with the current industry standard of blades made from a thermoset resin and outperforms certain thermoplastic resins intended to be recyclable.

Using incumbent technology, wind blades last about 20 years, and afterward they can be landfilled or shredded for use as concrete filler. The PECAN resin enables blades to be recycled using heat and methanol, producing materials that could be reused to manufacture new blades.

“It is truly a limitless approach if it’s done right,” says Ryan Clarke, postdoctoral researcher at NREL and first author of the paper. Clarke says the chemical recycling process was able to break down the 9-m prototype blade in about 6 hours.

“Nine meters is a scale that we were able to demonstrate all of the same manufacturing processes that would be used at the 60-, 80-, 100-meter blade scale,” says Robynne Murray, also an author on the paper.

Composites made from the PECAN resin held their shape, withstood accelerated weatherization validation and could be made within a time frame similar to the existing cure cycle for how wind turbine blades are currently manufactured.

The work was conducted by investigators at five NREL research hubs, including the National Wind Technology Center and the BOTTLE Consortium. The researchers demonstrated an end-of-life strategy for the PECAN blades and proposed recovery and reuse strategies for each component.

“The PECAN method for developing recyclable wind turbine blades is a critically important step in our efforts to foster a circular economy for energy materials,” says Johney Green, NREL’s associate laboratory director for Mechanical and Thermal Engineering Sciences.

source:NREL & www.ptonline.com

Today's KNOWLEDGE Share : Exposing the pitfalls of plastics mechanical recycling through cost calculation

Today's KNOWLEDGE Share

Exposing the pitfalls of plastics mechanical recycling through cost calculation:

The plastic industry needs to match the recycling goals set by the EU. Next to technological hurdles, the cost of plastics mechanical recycling is an important modality in this transition. This paper reveals how business economic cost calculation can expose significant pitfalls in the recycling process, by unravelling limitations and boundary conditions, such as scale.

By combining the business economic methodology with a Material Flow Analysis, this paper shows the influence of mass retention of products, the capacity of the processing lines, scaling of input capacity, and waste composition on the recycling process and associated costs. Two cases were investigated: (i) the Initial Sorting in a medium size Material Recovery Facility and (ii) an improved mechanical recycling process for flexibles − known as the Quality Recycling Process − consisting of Additional Sorting and Improved Recycling. Assessing the whole recycling chain gives a more holistic insight into the influences of choices and operating parameters on subsequent costs in other parts of the chain and results in a more accurate cost of recycled plastic products. This research concluded that the cost of Initial Sorting of flexibles is 110,08–122,53 EUR/t, while the cost of subsequent Additional Sorting and Improved Recycling ranges from 566,26 EUR/t for rPE Flex to 735,47 EUR/t for rPP Film, these insights can be used to determine a fair price for plastic products. For the Quality Recycling Process it was shown that rationalisation according to the identified pitfalls can reduce the cost per tonne of product by 15–26%.

source:Nicola Van Camp,Irdanto Saputra Lase , Steven De Meester,, Sophie Hoozée , Kim Ragaert 

Link:https://www.sciencedirect.com/science/article/pii/S0956053X24004513

Today's KNOWLEDGE Share:PACKING CHNAGES

Today's KNOWLEDGE Share

Why do thick parts need more packing than thin ones ?

Packing changes the parts size/volume/mass, but not the final density. Whatever is already solid at the end of fill (frozen skin) does not need any packing (shrinkage has already occurred !).

So, as the picture shows (in a slightly exaggerated way) in a thin part/section one only has to pack a tiny fraction of the total volume, whereas in a thick part/section, most of the volume will need to be packed, to compensate for the shrinkage.

Since thick parts are easy to fill and need more packing, it is not unusual to use a packing pressure much higher than the filling pressure. Something that might not fit the default values proposed by simulation...

Always think twice before accepting a default value.

source:Vito Leo

Today's KNOWLEDGE Share : Effect of post-curing on the mechanical properties of carbonized phenolic resins:

Today's KNOWLEDGE Share

Effect of post-curing on the mechanical properties of carbonized phenolic resins:

After curing, phenol-formaldehyde resins were post-cured at 160°C, 230°C, and 300°C in air for several hours, and then those post-cured samples were carbonized at 1000°C. The effect of post-curing on the physical properties and microstructure of the carbonized phenolic resin is reported in this article. The purpose of post-curing was to improve the mechanical properties of the carbonized resins. The post-curing process promoted the crosslinking reaction and the evolution of gases. The cured resin post-cured at a higher post-curing temperature (300°C) had a significantly higher weight loss, greater linear shrinkage and lower density than other samples.

During carbonization the post-curing process not only decreased the weight loss but also limited the shrinkage. Post-curing also promoted the formation of carbon basal planes and the chemical densification in structures of the final carbonized resins. The increase in post-curing temperature and time had the effect of reducing the linear shrinkage of the resin during carbonization. The TGA thermal analysis showed that the post-cured resins improved the total weight loss more than 15 wt% over the unpost-cured resin. The carbonized resins developed from the post-cured resins had a greater flexural modulus by about 10–50% and improved the linear shrinkage by about 10% over that developed from unpost-cured resins.

source :Tse-Hao Ko, Tsu-Sheng Ma

Today's KNOWLEDGE Share : GFRP MESH

Today's KNOWLEDGE Share

One truck vs. Six!

When it comes to transportation efficiency, the difference between GFRP mesh and traditional steel mesh is crystal clear. To transport the same amount of steel mesh, you would need 6 trucks like the one in this photo, but with GFRP mesh, just 1 truck does the job!

This lightweight innovation doesn't just save on logistics and costs; it also reduces fuel consumption, emissions, and time. That’s the kind of efficiency we aim for at Composite Tech FRP as we continue to provide cutting-edge composite solutions.

The future of construction is lighter, greener, and stronger with GFRP 💪

source:Anton Ocunev- Composite Tech FRP

Huntsman to launch gripping new footwear range at NW Materials Show

Footwear experts from Huntsman’s Polyurethanes business will be exhibiting at the NW Materials Show at the end of August where they will launch a gripping new soling development for the footwear industry.

Dependable, durable, and developed with circularity in mind, the new portfolio of high performing thermoplastic polyurethane (TPU) products will be of interest to footwear brands producing running, hiking and safety shoes.

Matthew Canoy, Global Marketing Director PU Elastomers at Huntsman, said: “We’re always excited to attend the NW Materials Show. This year there is an extra layer of anticipation as we prepare to launch a new range of soling materials for the footwear industry. Our latest product innovation follows the successful launch, last September, of SMARLITE® O liquid TPU (LTPU). The new technology we’ll be launching in August is compatible with SMARTLITE® O LTPU and is aligned with the sustainability, automation, customization and smart manufacturing needs of a sector that is renowned for fast-paced innovation.”

To register to receive more information about Huntsman’s new product line, go to:

https://www.getthegrip.online

Alternatively, visit Huntsman at the NW Materials Show at Booth 4007.

August 28-29, 2024

Oregon Convention Center

Portland, Oregon

source:Huntsman