Where can I find a laboratory that can identify SBR (styrene Butadiene

[1Sponge]

I am dealing with an issue regarding black specs appearing in a drinking water system. I suspect they are of an elastomer material – primarily SBR (Styrene Butadiene Rubber) but I have been unable to find a lab capable of confirming this. The specks are not soluble in Freon, hexane, Acetone, methylene chloride or nitric acid. I suspect SBR would not be soluble in these solvents-but I am not 100% sure. Any advice?
Any one else one into this problem in a distribution system?

(Specs started appearing after a switch to chloramines from chlorine for disinfection. At least one corroded SBR gasket has been found in the system-hence the SBR rubber suspicion).

 

[rconner]

I asked someone I consider a rubber expert about this, and he thought some folks at Akron Rubber Development Laboratories in Akron, Ohio might be able to help/analyze the particles for you. Perhaps they and/or the gasket manufacturer might even venture an opinion as to what has affected the gasket you have reported found? He also noted SBR would likely have limited solubility in hexane and is readily soluble in aromatics like toluene. On a side note, I suspect there are probably many potential things found in water and piping and plumbing sytems that might appear black, and even many different types of rubber items with different formulations etc. even within basic rubber types, in addition to pipe gaskets.

 

[1Sponge]

Thanks for the feedback! I will Look into Akron Rubber Labs... I agree in that there are many things that can be found in water and plumbing systems. We are hypothesizing SBR given the circumstantial evidence, hopefully we will be able to find a lab that can identify it whatever it is...

 

[bimr]

R.L. Hudson & Company may be able to help you:

http://www.rlhudson.com/profile_material.html

http://www.rlhudson.com/tech_chloramine.html

The black specs may be ferrous sulfide caused by sulfur in the water.

 

[1Sponge]

Bimr- wouldn't there have to be sulfur reducing organisms in the water in order for there to be ferrous sulfide present? How likely is this to be the case if the pipes contain dininfected drinking water? Please excuse my ignorance, but are there other ways for ferrous sulfide to get into piping systems outside of microbial activity? I.e. Can the break down of certain pipe materials produce this? And if so, what are they?

 

[1Sponge]

Oh and as an FYI, the black specs smear when warmed and stick to surfaces....im trying to look up the characteristics of ferrous sulfide now....Has anyone actually seen this precipitate before? Does it smear?

 

[bimr]

Occasionally, a well yields a water which is black with ferrous sulfide. Ferrous sulfide tends to be extremely divided, and it takes a very small quantity to blacken the water.

Sometimes such black waters may be encountered in dead-end water mains where bacterial action has resulted in reducing some of the sulfate content to sulfide.

 

[MrWizard]

I am doubtful these particles are SBR elastomer. You mentioned finding one "corroded" SBR gasket in the system. Are you certain it is SBR?

Several years ago, there was an article in the AWWA JOURNAL that reported exposure to chloramine deteriorated virtually all elastomers to some degree, even FKM. Testing was done on stock sheet rubber only, not pipe gaskets. In order to meet required properties of AWWA standards, pipe gaskets have other additives. These additives apparently improve resistance to chloramine attack as well. Other, less sophisticated elastomers, such as what may be used in the manufacture of toilet flapper valves do not perform so well.

The use of chloramine for disinfecting potable water is not new. There is one large, mid-western city that has used chloramine for this purpose for many decades. There was an occasion to recover two SBR gaskets that had been in service and exposed to chloraminated water for almost thirty years. These gaskets were tested at Akron Rubber and found to meet the physical requirements for new gaskets. Close scrutiny of the gaskets revealed the presence of minute cracks in the portion exposed to the treated water. However, the cracks were judged to be superficial and that the gaskets were still in the early stages of their service life cycles.

In recent years, a number of water agencies have switched from chlorine to chloramines in an effort to comply with EPA-mandated limits on Disinfection By-Products that are considered carcinogenic. Considering the number of rubber products (gaskets, seals, washers, hoses, etc.) in contact with treated water, this subject has been of some concern to those contemplating the switch to chloramine water treatment.

 

[sadochemeng]

try Bodycote Melrose Park facility, it is materials testing lab and they r into plastics and rubber and all, probably they ll do some FTIR or something and figure it out, but this is if the material is plastic or rubber based...