Hoppa till innehåll

Senaste nyheterna inom skidvärlden - i samarbete med längd.se

Hitta rtt skidor

Landslaget till vrldscuppremiren i Ruka

Snygg dubbel av Svensson och Peterson

Stina Nilsson visade vrldscupform

längdskidor, rullskidor, skidvalla & skidkläder från skistart
Atomic längdskidor
Rossignol längdskidor
Foto

Skistart HF Racing powder


  • Vänligen logga in för att kunna svara
48 svar till detta ämne

#41
oxberg

oxberg

    Medlem

  • Members
  • Pip
  • 393 inlägg

Här kan man köpa billigt fluor-karbon pulver (PVDF):

 

https://www.alibaba....0205477875.html

 

Skidorna kanske går som raketer med en behandling.



#42
oxberg

oxberg

    Medlem

  • Members
  • Pip
  • 393 inlägg
Skistart har börjat kalla det fluoro pulver på webshopen, men inte fluorokarbon eftersom det inte är det.

#43
Anl

Anl

    Veteran

  • Members
  • PipPipPip
  • 2 374 inlägg

LF, HF, fluorokarbon ... rent fluor är ju en gas och väldigt reaktiv, när man pratar om rent fluor i vallasammanhang menar man väl fullständigt fluorerade polymerer av typen ptfe? Eller?



#44
skogsvakt

skogsvakt

    Veteran

  • Members
  • PipPipPip
  • 1 625 inlägg
Innehållsförteckning på valla borde vara ett krav. Men det är lite som vin. Ingen ska få upptäcka bluffen med vad som finns i.
Mer fristil i längdsverige
Återinför skejtvasan
Visa respekt för sporten - åk med fäste!
41.57.63

#45
Dunderklumpen

Dunderklumpen

    Veteran

  • Members
  • PipPipPip
  • 3 510 inlägg

LF, HF, fluorokarbon ... rent fluor är ju en gas och väldigt reaktiv, när man pratar om rent fluor i vallasammanhang menar man väl fullständigt fluorerade polymerer av typen ptfe? Eller?


Just ptfe är väl mer en plast. Teflon eller "Gore-tex". Men rena fluorkarboner. Dvs inte "smältbara" paraffiner.

#46
Anl

Anl

    Veteran

  • Members
  • PipPipPip
  • 2 374 inlägg

Just ptfe är väl mer en plast. Teflon eller "Gore-tex". Men rena fluorkarboner. Dvs inte "smältbara" paraffiner.

Man kan kanske kalla ptfe för plast, men det är ju en helt ren fluorkarbon?

Fluorkarboner med väldigt kort kolkedja har ju vikt-procentuellt mer fluor, men jag tror de är gaser vid NTP? 

 

Så ren fluorkarbon i fast form vid rumstemperatur borde vara teflon?

Vad är valla-fluorpulver EGENTLIGEN, rent kemiskt?



#47
oxberg

oxberg

    Medlem

  • Members
  • Pip
  • 393 inlägg

Man kan kanske kalla ptfe för plast, men det är ju en helt ren fluorkarbon?

Fluorkarboner med väldigt kort kolkedja har ju vikt-procentuellt mer fluor, men jag tror de är gaser vid NTP? 

 

Så ren fluorkarbon i fast form vid rumstemperatur borde vara teflon?

Vad är valla-fluorpulver EGENTLIGEN, rent kemiskt?

 

The first fluorocarbon used in ski waxes, as an additive, was Teflon, (also known as PTFE, or polytetrafluoroethylene). In addition to its water repellent properties, PTFE is an excellent solid lubricant having one of the lowest coefficients of friction known. Unfortunately, PTFE lacks mechanical strength and does not hold up well to colder, aggressive snow. Also, since PTFE contains over 500 polymerized carbon atoms, it has a melting point much higher than polyethylene ski bases and cannot be used as a traditional ski wax to be melted into the pores of a ski base. As such, PTFE has been mostly limited to use in surface coat waxes, such as Maxiglide, and a few race waxes and additives (like Ski-Go 280) which again mostly stay on the surface of the ski.

In the late 80's, ski wax companies started to use fluorocarbon technology originally developed for painting the bottoms of boats and ships. Swix's Cera-F (properly pronounced "ché - ra", with a "ch" like in cheese and the "e" like a long "a" in English), was the first such commercially available ski-wax. Technically, these waxes are known as perfluorocarbons, with "per" meaning that all of the hydrogen atoms on the carbon chain have been replaced with fluorine atoms. These molecules contain about 20 carbons atoms, and melt at a low enough temperature that they could be ironed onto the ski without melting the base.

 

Fluorocarbon waxes have the advantages of having a very high degree of water repellency plus a very low friction coefficient. In addition, they repel dirt particles (which tend to be negatively charged) and resist oil (from grooming machines) and waxy pollen from trees. As such, fluorocarbon waxes are excellent for Spring, when snow tends to be both wet and dirty.

 

Fluorocarbon waxes, however, have several drawbacks. First of all, their manufacturing process (by electro fluorination) is complex and very costly. There are only a couple manufacturing plants (of the raw materials) and processing laboratories in the entire world. Ski wax companies do not manufacture their own fluorocarbon wax, but rather buy these products from the same processing labs.

 

Just like paraffins and PTFE, fluorocarbon waxes also lack mechanical strength and are thus easily penetrated by cold snow crystals. As such, fluorocarbon waxes tend to "stick" in temperatures below 21°F, especially if the humidity is low or the snow is dry. In the last several years, the processing labs have developed different fluorocarbon wax structures, often combined with other atoms, to increase the mechanical strength and temperature ranges. For example, STAR now has three different fluorocarbons: F1 (powder or solid) for new warmer snow, F2 (powder or solid) for older (corned) warmer snow, and F3 (powder only) for colder humid conditions, plus their new "Dice" pure fluorocarbon rub-on solids, again in three temperature ranges. That's a total of 8 different pure fluorocarbon waxes from just one wax company!

 [...]

 

Läs allt här --> http://www.rideandgl...uoro_waxing.htm



#48
Anl

Anl

    Veteran

  • Members
  • PipPipPip
  • 2 374 inlägg

 

The first fluorocarbon used in ski waxes, as an additive, was Teflon, (also known as PTFE, or polytetrafluoroethylene). In addition to its water repellent properties, PTFE is an excellent solid lubricant having one of the lowest coefficients of friction known. Unfortunately, PTFE lacks mechanical strength and does not hold up well to colder, aggressive snow. Also, since PTFE contains over 500 polymerized carbon atoms, it has a melting point much higher than polyethylene ski bases and cannot be used as a traditional ski wax to be melted into the pores of a ski base. As such, PTFE has been mostly limited to use in surface coat waxes, such as Maxiglide, and a few race waxes and additives (like Ski-Go 280) which again mostly stay on the surface of the ski.

In the late 80's, ski wax companies started to use fluorocarbon technology originally developed for painting the bottoms of boats and ships. Swix's Cera-F (properly pronounced "ché - ra", with a "ch" like in cheese and the "e" like a long "a" in English), was the first such commercially available ski-wax. Technically, these waxes are known as perfluorocarbons, with "per" meaning that all of the hydrogen atoms on the carbon chain have been replaced with fluorine atoms. These molecules contain about 20 carbons atoms, and melt at a low enough temperature that they could be ironed onto the ski without melting the base.

 

Fluorocarbon waxes have the advantages of having a very high degree of water repellency plus a very low friction coefficient. In addition, they repel dirt particles (which tend to be negatively charged) and resist oil (from grooming machines) and waxy pollen from trees. As such, fluorocarbon waxes are excellent for Spring, when snow tends to be both wet and dirty.

 

Fluorocarbon waxes, however, have several drawbacks. First of all, their manufacturing process (by electro fluorination) is complex and very costly. There are only a couple manufacturing plants (of the raw materials) and processing laboratories in the entire world. Ski wax companies do not manufacture their own fluorocarbon wax, but rather buy these products from the same processing labs.

 

Just like paraffins and PTFE, fluorocarbon waxes also lack mechanical strength and are thus easily penetrated by cold snow crystals. As such, fluorocarbon waxes tend to "stick" in temperatures below 21°F, especially if the humidity is low or the snow is dry. In the last several years, the processing labs have developed different fluorocarbon wax structures, often combined with other atoms, to increase the mechanical strength and temperature ranges. For example, STAR now has three different fluorocarbons: F1 (powder or solid) for new warmer snow, F2 (powder or solid) for older (corned) warmer snow, and F3 (powder only) for colder humid conditions, plus their new "Dice" pure fluorocarbon rub-on solids, again in three temperature ranges. That's a total of 8 different pure fluorocarbon waxes from just one wax company!

 [...]

 

Läs allt här --> http://www.rideandgl...uoro_waxing.htm

 

Det står "Fluorocarbon waxes work because the negatively charged fluorine atoms and negatively charged oxygen portion of the water molecule repel each other". Det stämmer väl inte? Det är väl för att ptfe är helt opolär som det är hydrofobt.

 

Sen skulle det vara intressant att höra från nån av polymerexperterna på forumet varför inte rena kolväten och ptfe skulle kunna blanda sig lika väl som de gör med delvis fluorerade kolväten. I samtliga fall är väl molekylerna i princip helt opolära och borde blanda sig lika väl? (Men vad vet väl en geolog ...) 



#49
Anl

Anl

    Veteran

  • Members
  • PipPipPip
  • 2 374 inlägg

https://www.skiinghi...history-ski-wax






0 användare läser detta ämne

0 medlemmar, 0 gäster, 0 anonyma medlemmar