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Hexamethylene diisocyanate (HDI) is the organic compound with the formula (CH 2) 6 (NCO) 2. It is classified as an diisocyanate. It is a colorless liquid. [2] It has sometimes been called HMDI [3] but this not usually done to avoid confusion with Hydrogenated MDI.
This diamine is used to produce isophorone diisocyanate which has certain niche applications. [4] Isophorone diisocyanate is used to produce specialty polyurethanes. Full hydrogenation gives 3,3,5-Trimethylcyclohexanol, a precursor to both sunscreens and chemical weapons.
Isophorone diisocyanate (IPDI) is an organic compound in the class known as isocyanates. More specifically, it is an aliphatic diisocyanate. It is produced in relatively small quantities, accounting for (with hexamethylene diisocyanate ) only 3.4% of the global diisocyanate market in the year 2000. [ 2 ]
1,6-Hexanediol can improve the hardness and flexibility of polyesters as it contains a fairly long hydrocarbon chain. In polyurethanes, it is used as a chain extender , and the resulting modified polyurethane has high resistance to hydrolysis as well as mechanical strength, but with a low glass transition temperature.
For example, the trimer of 1,6-hexamethylene diisocyanate is also known as HDI-biuret. In the anhydrous form, the molecule is planar and unsymmetrical in the solid state owing to intramolecular hydrogen bonding. The terminal C–N distances of 1.327 and 1.334 Å are shorter than the internal C–N distances of 1.379 and 1.391 Å.
Hexamethylenediamine or hexane-1,6-diamine, is the organic compound with the formula H 2 N(CH 2) 6 NH 2. The molecule is a diamine, consisting of a hexamethylene hydrocarbon chain terminated with amine functional groups. The colorless solid (yellowish for some commercial samples) has a strong amine odor.
Hansen solubility parameters were developed by Charles M. Hansen in his Ph.D thesis in 1967 [1] [2] as a way of predicting if one material will dissolve in another and form a solution. [3] They are based on the idea that like dissolves like where one molecule is defined as being 'like' another if it bonds to itself in a similar way.
Photolithography makes this process possible through the combined use of hexamethyldisilazane (HMDS), photoresist (positive or negative), spin coating, photomask, an exposure system and other various chemicals. By carefully manipulating these factors it is possible to create nearly any geometry microstructure on the surface of a silicon wafer. [1]