Poly isocyanurates

Modification of poly(carbodiimide) foams with polyols afford hybride foams containing urethane sections. However, the thermal stabilities of the poly (urethane carbodiimide) foams are lower. Using isocyanate trimerization catalysts, such as l,3,5-tris(3-dimethylaminopropyl)hexahydro-s-triazine, in combination with the phospholene oxide catalyst gives poly(isocyanurate carbodiimide) foams with improved high temperature properties. The cellular poly(carbodiimide) foams derived from PMDI incorporate six-membered ring structures in their network polymer structure. ... 

A research program to have benzylic ether-type resin react with polyisocyanate for producing polyurethane or urethane-modified poly-isocyanurate foam is being promoted. A foam which has intermediate properties between phenolic foam and polyurethane foam can be produced. 

More recently Nicholas and Gmitter [23] prepared heat-resistant, rigid poly-isocyanurate foams and Sandler [24] reported on a similar process to prepare heat-resistant adhesives for aluminum. The trimerization agents reported by Sandler [24] were various metal salts and organometallic compoimds such as tri-n-butylantimony oxide [25] as shown in Table X. 

Poly(isocyanurate) Good mechanical property, flame retardancy and morphological stability, cheap Poor heat resistance... 

For polyurethane foams, solid dicarboxylic acids such as fumaric, isophthalic or chlorendic acids are supplemented with sulphur, while alkali metal and ammonium fluoroborates (KBF4, NH4BF4) were patented as smoke suppressants for poly-isocyanurates. ... 

Poly(isocyanurates) are produced by the cyclotrimerization of isocyanates, for example, p-diphenyl diisocyanates (see also Section 28.4) ... 

Spra5ung of the foam formulation by special two-stream spray gims onto suitable surfaces is often conducted. On-site applications for spray foam include roofs, tanks, vessels, cavity walls, and pipes. Spray-applied polyurethane foams are produced in densities ranging from 1.3 to 3.0 Ib/ft (21-48 kg/m ). The lower-density foams are used primarily in nonload-bearing applications (cavity walls and residential stud-wall insulation). The higher-density foams are used in roofing applications. The 1 1 volume ratio of the A and B components required for spray foams excludes the poly(isocyanurate) chemistry from this application. In spray foam formulations, PMDI in combination with the more reactive amine polyols... 

A rigid poly(urethane) foam or poly(isocyanurate) foam can be prepared by reacting a poly(ol) and an isocyanate in the presence of a... 

Commonly used isocyanates are toluene dhsocyanate, methylene diphenyl isocyanate, and polymeric isocyanates. Polyols used are macroglycols based on either polyester or polyether. The former [poly(ethylene phthalate) or poly(ethylene 1,6-hexanedioate)] have hydroxyl groups that are free to react with the isocyanate. Most flexible foam is made from 80/20 toluene dhsocyanate (which refers to the ratio of 2,4-toluene dhsocyanate to 2,6-toluene dhsocyanate). High-resilience foam contains about 80% 80/20 toluene dhsocyanate and 20% poly(methylene diphenyl isocyanate), while semi-flexible foam is almost always 100% poly(methylene diphenyl isocyanate). Much of the latter reacts by trimerization to form isocyanurate rings. 

DADC may be polymerised industrially with small amounts of other miscible Hquid monomers. Some acryflc ester monomers and maleic anhydride may accelerate polymerisation. Copolymerisation with methacrylates, diaHyl phthalates, triaHyl isocyanurate, maleates, maleimides, and unsaturated polyesters are among the examples in the early Hterature. Copolymers of DADC with poly-functional unsaturated esters give castings of high clarity for eyeglass lenses and other optical appHcations (20). 

Poly (Difluoroamino)-Substituted Cyanuric and Isocyanuric Acid Derivatives. For Cyanuric Acid and Derivatives see Vol 3, C589-R ff. For Difluoroamino Compounds see Vol 5, DI258-L... 

In an acetone extract from a neoprene/SBR hose compound, Lattimer et al. [92] distinguished dioctylph-thalate (m/z 390), di(r-octyl)diphenylamine (m/z 393), 1,3,5-tris(3,5-di-f-butyl-4-hydroxybenzyl)-isocyanurate m/z 783), hydrocarbon oil and a paraffin wax (numerous molecular ions in the m/z range of 200-500) by means of FD-MS. Since cross-linked rubbers are insoluble, more complex extraction procedures must be carried out (Chapter 2). The method of Dinsmore and Smith [257], or a modification thereof, is normally used. Mass spectrometry (and other analytical techniques) is then used to characterise the various rubber fractions. The mass-spectral identification of numerous antioxidants (hindered phenols and aromatic amines, e.g. phenyl-/ -naphthyl-amine, 6-dodecyl-2,2,4-trimethyl-l,2-dihydroquinoline, butylated bisphenol-A, HPPD, poly-TMDQ, di-(t-octyl)diphenylamine) in rubber extracts by means of direct probe EI-MS with programmed heating, has been reported [252]. The main problem reported consisted of the numerous ions arising from hydrocarbon oil in the recipe. In older work, mass spectrometry has been used to qualitatively identify volatile AOs in sheet samples of SBR and rubber-type vulcanisates after extraction of the polymer with acetone [51,246]. 

Dicyanates react with diisocyanates. The poly addition results in the formation of crosslinked polymers with cyanurate and isocyanurate rings [32]. The polymers have high deformation and decomposition temperature in the case of a crosslinked copolymer from 9,9-bis(4-cyanatophenyl)fluorene the corresponding values are 480 °C and 440 °C (in air), respectively. 

Modification of the poly(carbodiimide) foams, using polyols as comonomers, is possible, but the excellent thermal and flammability properties are reduced. Poly(carbodiimide isocyanurate) foams can also be continuously produced using 1,3,5-tris-(3-dimethylaminopropyl)-hexahydro-s-triazine as the cocatalyst. Other trimerization catalysts, such as potassium 2-ethylhexanoate and quaternary ammonium carboxylate (Dabco TMR 2) are also used as cocatalysts in the formation of poly(carbodiimide isocyanurate)... 

Figure 3.78. Scanning electron microscope images of a coin manufactured by TP initiated polymerization of tris(2-hydroxyethyl)isocyanurate triacrylate in the presence of poly(styrene-co-acrylonitrile) as binder and 167 as TP initiator using a frequency-doubled Nd YAG microlaser (0.5-ns pulses, 6.5-kHz repetition rate, wavelength 532 nm, average power 1.2 mW, 1.8-mm focal spot) (a) overview and (b) part of the coin with larger magnification. (From Ref. [136] with permission of the Optical Society of America.)...

The microphase separation of a semi-interpenetrating network based on polyurethane and poly(epoxy isocyanurate) containing Fe2O3 was studied by dynamic mechanical spectroscopy. The preferential absorption of polyurethane on... 

In the same period it was found that using tris-(2-hydroxyethyl)-isocyanurate (THEIC) for polymer branching increases the cut through of the polyester film substantially [7]. The poly(ester-imide)s were modified with THEIC, and improved materials were obtained (Fig. 1) [8]. 

Higher alkylene oxylated derivatives of isocyanuric acid were claimed to be useful for poly(ester-imide) preparations [43], and also l,3,5-tris(2-hydroxye-thyl)-hexahydro-l,3,5-triazine-2,4-dione, prepared by reacting ethylene oxide and hexahydro-l,3,5-triazine-2,4-dione [44]. No wire enamels made from these polyols have been seen on the market. 

From hexahydrophthalic anhydride, aminoethanol, neopentylglycol, isoph-thalic acid, and trimellitic anhydride a carboxyl terminated poly(ester-imide) resin is made and formulated with triglycidyl isocyanurate, pigments, and additives to give a powder coating with excellent heat resistance and no chalking after 5 month at 120 °C [236]. 

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