Usage of rigid PVS vs HIPS 1

[amlsna]

I recently had a supplier go under and they were supplying an extruded rigid PVC part. Tooling was transferred to a new supplier and they are unable to produce the part in PVC, but would like to offer it in HIPS. I know that the 2 materials are fairly inter-changeable for some applications, but I was hoping someone could help to educate me on any negative affects from the switch to HIPS.
Thanks,

 

[patprimmer]

The two materials are quite different in many properties. What is your application and environment of use.

Regards

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[amlsna]

Greetings. I guess that I over-stated my case about the materials being inter-changeable, and that was because I was thinking of my application, which is:
Indoor usage only, with little load bearing conditions, and no deformative stresses applied aside from housing electrical cables.
So most conditions would be ambient and without exposure to any harsh chemicals.
Sincerely,

 

[patprimmer]

The main differences will be flammability. PVC is inherently self extinguishing. Styrene burns happily.

Without looking up properties charts, I think the flexural modulus vs impact strength trade off might be different for both materials. I think PVC will have better impact without sacrificing as much flex mod. I am sure you can look up data sheets yourself.

Regards

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[Demon3]

For your application both sound fine as the main advantages of PVC are the weathering and chemical resistance, which you don't need. You can find properties for both polymers at

http://www.matweb.com,

it's free and very useful. HIPs is not a single material but a whole range so you can choose a grade with mechanical properties most closely matching your former material.

As Pat mentioned though PVC is intrinsically self extinguishing and that might be important for housing electrical cables. HIPs burns readily with lots of black smoke. ABS would work too and has added chemical resistance compared to HIPs and some added cost, but again it won't be fire resistant.

 

[Pud]

Flame retardant ABS might be a suitable replacement - it is used quite a lot for electrical stuff.

If it's for electrical trunking, then I would find someone who is willing to extrude PVC.

Cheers


Harry

 

[dwightdixon]

HIPS has a problem with resistance to the DOP plasticizer that is likely in the flexible PVC cabling to be contained. I would transfer the tooling to someone who can handle the PVC you were formerly using. There are alot of extruders out there that can handle rigid PVC. It is alot safer than trying to change materials mid stream production.