Query on Rubber products (EPDM, Silicone, BR, NBR, Neoprene, TPE)

[vivkrish]

Hello All,

We are using some of the rubber products (EPDM, Silicone, BR, NBR, Neoprene, TPE(Santoprene)) in our factory.

We are purchasing the rubber component from our suppliers.

Currently we are ensuring the material by verifying physical properties of those material once in 6 months.

Now our management advised to confirm the material quality once in a month.

I Have refused to our management for their requirement, since the testing cost will be high.

So I want to know what are the properties(Chemical Composition or Physical Properties) are quite enough to confirm the material quality (Its for our internal, I will not share with my customers)

Anyone suggest me..

Thanks,
Vivkrish.

 

[Miner]

Are you purchasing the polymer itself or a rubber compound with those polymers as a base?

What is driving the management directive? Are you having quality issues with the material? If issues, are they processing issues, functional issues, properties issues? Knowing this will aid in our responses.

I have 15 years experience in the rubber industry, primarily with EPDM and NR.

 

[NikkiQSM]

Hi Vivkrish,

I work for a medical plastics compounder - and we use the whole rainbow of polymers including TPE's and Santoprene.

We do not have check as often as your management is requesting but when the material arrives we conduct an incoming inspection.

We use a digital microscope to check for contamination such as carbon char. Other than that, we will verify the properties on the COA for the material. If it has a melt flow of 10, we run a melt flow to verify it matches. Melt flow is a good test to conduct to verify the molecular weight of the material. Moisture is also a good one. If you have material sitting around for a while, you will want to check the moisture before processing.

Hope this helps!

 

[vivkrish]

Are you purchasing the polymer itself or a rubber compound with those polymers as a base?

What is driving the management directive? Are you having quality issues with the material? If issues, are they processing issues, functional issues, properties issues? Knowing this will aid in our responses.

I have 15 years experience in the rubber industry, primarily with EPDM and NR.

Hi Minor,

Thanks...! Am answering your questions..

1. We are purchasing as a rubber component which is base of polymers.

2. Currently we don't have any quality issues. We faced some of the issues on the above mentioned products a mean while.

While verifying the process and polymer, polymer has some issues(Carbon Content is more - Formulation problem)

So we need to verify(Periodically) all the rubber products in incoming inspection as a product or raw material condition.

For that i need the above requirements.

Thanks..
Vivkrish.

 

[vivkrish]

Hi Vivkrish,

I work for a medical plastics compounder - and we use the whole rainbow of polymers including TPE's and Santoprene.

We do not have check as often as your management is requesting but when the material arrives we conduct an incoming inspection.

We use a digital microscope to check for contamination such as carbon char. Other than that, we will verify the properties on the COA for the material. If it has a melt flow of 10, we run a melt flow to verify it matches. Melt flow is a good test to conduct to verify the molecular weight of the material. Moisture is also a good one. If you have material sitting around for a while, you will want to check the moisture before processing.

Hope this helps!

Hi Nikki,

We do have microscope in our factory, is any special feature required to measure the chemical composition. I hope we can't analyse the chemical composition by microscope.

Also we can't test MFI / MVR for rubber materials. TPE is elastomer(Rubber like Material) not a rubber.

Can you please clarify the microscopic technique.?

Thanks,
Vivkrish.

 

[Miner]

1. We are purchasing as a rubber component which is base of polymers.

2. Currently we don't have any quality issues. We faced some of the issues on the above mentioned products a mean while.

While verifying the process and polymer, polymer has some issues(Carbon Content is more - Formulation problem)

So we need to verify(Periodically) all the rubber products in incoming inspection as a product or raw material condition.

The only tests that would typically be suitable for incoming inspection are the rheology (rheometer) and processibility (viscometer) tests. The rheology will quantify the time to onset of cure, cure rate and final modulus, while the viscometer will quantify the minimum viscosity. The combination of these two tests will detect a lot of problems, but cannot detect all the problems.

They also cannot pinpoint the specific cause of a problem, only that a problem exists. For example, excess carbon black may cause the final modulus to be out of spec. You will know that it is out of spec, but not why it's out of spec (i.e., due to excess carbon black).

Other tests require a well-equipped lab to support them. These include molecular weight distribution, DSC, TSC, etc., and are not suitable for incoming inspection.