Diacrylate diisocyanate

Reaction-induced phase separation is certainly also the reason for which an inhomogeneous structure is observed for photocured polyurethane acrylate networks based on polypropylene oxide (Barbeau et al., 1999). TEM analysis demonstrates the presence of inhomogeneities on the length scale of 10-200 nm, mostly constituted by clusters of small hard units (the diacrylated diisocyanate) connected by polyacrylate chains. In addition, a suborganization of the reacted diisocyanate hard segments inside the polyurethane acrylate matrix is revealed by SAXS measurements. Post-reaction increases the crosslink density inside the hard domains. The bimodal shape of the dynamic mechanical relaxation spectra corroborates the presence of a two-phase structure. 

The hydroxyl groups can be esterified normally the interesting diacrylate monomer (80) and the biologicaky active haloacetates (81) have been prepared in this manner. Reactions with dibasic acids have given polymers capable of being cross-linked (82) or suitable for use as soft segments in polyurethanes (83). Polycarbamic esters are obtained by treatment with a diisocyanate (84) or via the bischloroformate (85). 

Baumgart et aL (3) prepared scratchproof, radiation-curable film-forming coatings by condensing siloxane tetraol, hydroxylethyl acrylate, and hexanediol diacrylate with excess hexamethylene diisocyanate catalyzed by dibutyltin dilaurate. 

The reactive oligomer can be any low-molar-mass polymer containing at least a couple of double bonds. It can be based on a polyester, polyether, or polyurethane backbone. One mole of a, oo-OH-terminated polyester or polyether is prereacted with two moles of acrylic acid to obtain an a, oo-diacrylate oligomer. For polyurethanes, 1 mole of a, m-diisocyanate oligomer is prereacted with 2 moles of hydroxyethylacrylate (Sec. 2.2.3c). 

Photoinitiator concentration 4 equiv.% of BAE with respect to the reactive acrylate group in the fonnulation. Irradiation conditions 45 mW/cm by a high pressure mercury lamp PTMG urethane diacrylate obtained by reacting PTMG-diisocyanate with 2-hydroxyethyl acrylate... 

HC yellow no. 4. See HC yellow 4 HDA. See Hydroxylamine HDDA. See 1,6-Hexanediol diacrylate HD-Eutanol . See Oleyl alcohol HDI. See Hexamethylene diisocyanate HDI-based isocyanurate. See Hexamethylene diisocyanate polymer... 

DMSO using persulfate as the initiator. Chen et al. studied FP of poly(propylene oxide) glycol, 2,4-toluene diisocyanate, and 1,4-butanediol with the catalyst stannous caprylate in dimethylbenzene. At room temperature, bulk polymerization did not occur quickly, and the pot life could be extended to 6 h if the solution was cooled to 10 °C. Mariani et al prepared diurethane diacrylates. 

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