2929.90.05.00 - 2,2'-Bis(4-cyanatophenyl)-1,1,1,3,3,3-hexafluoro- propane; 2,2-Bis((4-cyanatophenyl) propane; 1,1-Ethylidenebis (phenyl-4-cyanate); 4,4'-Methylene bis(2,6-dimethylphenylcyanate); and 1,3-Phenylenebis (1-methylethylidenebis) cyanic acid, 1,4-phenylene ester

This HTS category, 2929.90.05.00, specifically classifies certain organic compounds characterized by the presence of a cyanate functional group. The enumerated substances, including 2,2'-Bis(4-cyanatophenyl)-1,1,1,3,3,3-hexafluoropropane and various other bis-cyanate compounds derived from propane, ethylidene, methylene, and phenylene backbones, are primarily used as monomers or cross-linking agents in the production of high-performance polymers and resins, such as cyanate ester resins known for their excellent thermal stability, low dielectric constant, and mechanical strength.

Within the broader grouping of "Other compounds with nitrogen function," this subheading distinguishes itself by the precise chemical structure and the presence of the cyanate (-OCN) group, as opposed to other nitrogen-containing functional groups like amines, amides, or nitriles. The specific chemical names and structural identifiers provided are crucial for accurate classification, ensuring that only these particular cyanate-functionalized organic compounds are included here.

As this is a leaf node within the HTS, there are no further subdivisions. Classification under 2929.90.05.00 is definitive for the listed substances when imported or exported, provided they meet the described chemical composition and are not intended for specific end-uses that might be covered by other chapters or headings. The focus remains on the inherent chemical properties and identity of the compounds themselves.