Poly semicarbazide

Semicarbazide and its derivatives including thiosemicarbazide react with 2-poly-fluoroacyl-cyclohexanones, giving exclusively hydroxy-pyrazolines (99IZV361) (Scheme 107). The choice between the two isomeric possible forms, F and X, was made based on an X-ray investigation (for the derivative with the -C6F13 substituent). 

As trunk polymer a polyetherurethane semicarbazide ("R5 325", Fa. Technochemie, Dossenheim, FRG), composed of 4,4 -diisocyanatodiphenylmethane, poly(oxytetra-methylene) and isophthalic acid dihydrazide was used. 

Polyurethane-semicarbazides (in earlier reports, they are also called poly-urethane-acylsemicarbazides) are linear polymers containing urethane and (acyl)semicarbazide groups in their macromolecules. Sulfur or phosphorus can also be included in the macrochains [2]. 

The sulfur-containing polyurethane-semicarbazides are usually called poly-urethane-sulfosemicarbazides. The chemical and thermal properties of these polymers depend on the valent state of the sulfur atom included in the macro-... 

The study of the ignition time, the time of self-extinction, and the weight losses at burning has shown that the synthesized phosphorus-containing poly-urethane-semicarbazides are among the conventional fire-proof or self-extinguishing materials. 

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