Cyclopolymerization of α,ω‐polymethylene diisocyanates

Abstract

The study of polymerization of α,ω‐polymethylene diisocyanates, tetramethylene, trimethylene, ethylene, and methylene diisocyanate, was carried out by the use of basic catalysts and polar solvents. Soluble polymers were obtained. Structures of the polymers were determined on the basis of solubility, infrared absorption, x‐ray diffraction, and chemical reactions, especially aminolysis of the polymers. It was shown that these polymers contained heterocyclic recurring units (imidazolidone and imidazoline) in each polymer chain. Finally, a possible mechanism of this kind of cyclopolymerization is described.

Thermodynamics of 1,4-diisocyanatobutane in the range from T→ (0 to 360) K at standard pressure

“…The sample of DIB from Aldrich, previously purified by the procedure described elsewhere [7] calorimetrically studied in the work. The content of nonidentified impurities in the sample, as determined by the calorimetry method from a decrease of the melting temperature, was (0.46 ± 0.02) mol%.…”

“…A good deal of works [3][4][5][6][7][8] are devoted to the study of isocyanate properties, specifically thermodynamic ones. 1,4-Diisocyanatobutane (DIB) that finds also application in industry is one of representatives of this class.…”

Versatile Organometallic Initiators for the Living Polymerization of Isocyanates

“…The IR spectra of poly-IX showed two carbonyl absorptions at 1778 and 698 cm" 1 and no absorption at 2270 cm" 1 , which would have indicated the presence of uncyclized isocyanate groups. These two absorptions have been assigned as the inter-ring carbonyl and intra-ring carbonyl stretching frequencies, respectively [10,11]. GPC trances of the polymers showed monomodal molecular weight distributions and a range of polydispersities (1.2 to 1.8).…”

Addition Polymers of Monofunctional Isocyanates

“…The structure of the polymers from a,co-polymethylene diisocyanates is much less exclusive [12]. Three types of structure have been detected by IR analysis.…”

“…a,w-Polymethylene diisocyanates, OCN • (CH^nNCO, have been polymerized by Shashoua's method [12], They give soluble polymers of linear noncross-linked structures.…”