Can Viton Meet the Customs Definition of "Synthetic Rubber"? 2

[texlex]

Whether it ever is or not, is Viton capable of being vulcanized with sulfur? This is required for Viton to be considered, for Customs purposes (see definition below), to be a "synthetic rubber."

Any assistance would be appreciated.

I am an attorney and assist clients with importing matters. One of my clients has been informed by U.S. Customs that Viton o-rings are not properly classifiable as “other articles of vulcanized rubber other than hard rubber: other: gaskets, washers, and other seals: other: o-rings."

Instead, Customs requires that they be classified as “other articles of plastics and articles of other materials of headings 3901 to 3914: other: gaskets, washers, and other seals: o-rings.”

The Customs definition of “synthetic rubber,” found at Harmonized Tariff Schedule (HTS) Chapter 40, Note 4., provides as follows:

"In note 1 to this chapter and in heading 4002, the expression "synthetic rubber" applies to:

(a) Unsaturated synthetic substances which can be irreversibly transformed by vulcanization with sulfur into nonthermoplastic substances which, at a temperature between 18°C and 29°C, (will pass a stretch and recovery test)...substances necessary for the cross-linking, such as vulcanizing activators or accelerators, (and certain other substances) may be added. However, the presence of any substances not necessary for the cross-linking, such as extenders, plasticizers and fillers, is not permitted."

Parentheticals are my paraphrasing.

 

[berti]

Hi texlex

importing rubbers including FKM we have same problem for many years and I am afraid the customs officer is right - like always ;-)

Some saturated rubbers (FKM, CPE, EPM, ECO)are - seen from tariff - plastics.

It costs us a lot of money because all 4002 materials do not cost import duty to EC, but all the above mentioned 5 to 10 %. So we tested several ways to apply sulfur cure - but no reasonable results.

Sorry for bad news

Berti

 

[ElastomerXpert]

This answer may be too late to be helpful, but I have to tell you that this is bureaucracy at its worst. There are more kinds of rubber NOT vulcanizable by sulfur than there are kinds that are, and on top of that, Natural Rubber from trees is of course almost always vulcanized using sulfur! Any number of textbooks from the Rubber Division of the American Chemical Society will confirm this, including the easy-to-read booklet "Introduction to Rubber Technology". So... how did you make out?

 

[texlex]

For whatever reasons, the parties who drafted the Harmonized Tariff Schedules (used by the U.S., the E.U., and about 170 countries total) created a situation where, by definition, synthesized materials with similar rubbery stretch charateristics are alternatively classified (for Customs purposes) as "synthetic rubber" if vulcanizable with sulfuror or as a "plastic elastomer," if not. Almost certainly, at some point in the process of drafting the tariff language, that definition made a distinction that favored some party to the detriment of some competitor. And, that party successfully had that definition adopted. In the alternative, it could have arisen because one of the nomenclature drafters grabbed a reference book that discussed synthetic rubbers and dsescribed their characteristics as they were known to be at that time.

We have concluded that Viton doesn't conform to the definition and is, thus, classifiable as a plastic elastomer. One implication is a somewhat higher tariff rate. A more problematic implication is the knowledge that hundreds of my client's imported items (gaskets, o-rings, washers, seals, etc.) must be now scrutinized to determine whether they should be classified in one provision or the other. Previously, the knowledge that the items were gaskets, o-rings, etc., and the use of the synthetic rubber tariff provision was deemed sufficient.

Respecting similar items made from variations of NBR, however, we have concluded that the NBR materials do meet the definition and are, thus, correctly classifiable as articles of synthetic rubber. On that point, I would appreciate any feedback confirming or qualifying.

Thanks,
Texlex

 

[ElastomerXpert]

Just in case it's ever of any interest, I will mention (hoping to not break any hard rules) that part of my work in the past few years has been as an Expert Witness in applied Rubber Technology. If anybody ever tries to fix the Customs definitions (how likely is that?) I would be glad to help.

R J Del Vecchio
Technical Consulting Services
(consultant in Applied Rubber Technology)

 

[ElastomerXpert]

I had sent a reply about which elastomers are readily vulcanized by sulfur, apparently it got lost in the ether. The answer is that NBR, HNBR (some grades), SBR, EPDM, BR, & IR are all sulfur curable.

R J Del Vecchio
Technical Consulting Services
(consultant in Applied Rubber Technology)