alternative injection molding material to ECTFE

[gao7857]

Hi there,

I am looking for an alternative injection molding material for ECTFE. Basically need to have "low smoke " feature and comparable mechanical properties.

Thanks,
Gao

 

[Demon3]

You can compare mechanicals of all plastics for free at

http://www.matweb.com

If you're using ECTFE you're not just using it for mechanicals as other plastics would get you there far more cheaply. Probably you need great chemical resistance or some other property too.

Chris DeArmitt PhD FRSC CChem

 

[patprimmer]

I never recommend any material on such limited data. It takes some understanding of the application or at least what properties are most required and why.

Hence my reluctance to comment earlier.

Regards
Pat
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[gao7857]

Sorry for the unclear descriptions.
The product is for air handling applications, it need to have UL V-level fammability, good service temperature (RTI>=125, that of ECTFE). It need similar mechanical strength and chemial resistance, and good to process. Do not want fluoropolymers.
I found PEI, PEEK as candidates, but they need higher mold temperature that seems can only achieved by oil. Also product-life is an issue, I noticed that ECTFE can claim >5 years but PEEK 1~2 years.

 

[patprimmer]

You need to do a lot more homework

It needs UL V what. There are 3 different levels.

Good is an extremely vague term for service temperature. Also service temperature can be heat deflection, continuous use or a ULrating for electrical insulation. RTI is not a service temperature, it's Relative Tracking Index, which seems a weird requirement for an air duct.

Good chemical resistance also seems strange for an air duct. Do you have any particular types of chemical in mind or are you talking all chemicals.

Regards
Pat
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[gao7857]

Hi Pat,

V0/1/2 all acceptable since they dont support burning, so can claim self-distinguish. V0 is the best.
What would be appropriate requirements for air duct? Sorry I am not familiar with HVAC. We also have smoke tests that seems all materials can pass. Because mechanical strength is the main concern, RTI-str and RTI-imp are main indicators.
As for chemical resistance, it will be general industrial chemicals like mild acid and base; do not expect encounter with organic solvents.
This part is not structural component nor withstand large load. I guess that's why it does not have strict requirements.

Thanks,
Yan

 

[patprimmer]

OK

What's wrong with FR PP or FR PET.

Regards
Pat
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[gao7857]

Hi Pat,

Thanks for the recommendations. FR PP and FR PET are definitely good directions based on RTI, strength and molding. I did not look at these two before and I appreciated it.
What I learnt from our marketing is that the customer got used to these Halar material and it will raise their concern if some parameters are lower than before. ECTFE has some radiation resistance; although it is not a necessity for air duct, it becomes a marketing point and something we want to keep. (this one has a bit history) That's why I start to look for PEEK and PEI type of things (also PS, PPSU, etc), something that can looks equivalent or better than ECTFE.

Thanks,
Yan

 

[patprimmer]

Just remember the FR additive can reduce other properties as can colours. Some colours really ruin RTI.

Regards
Pat
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