2,4-Tolylene diisocyanate, reaction with

The second type of composition is exemplified by a wide variety of acrylate- or methacrylate-ester derivatives of conventional ink vehicles combined with a photoinitiator 1. The reaction product of tung oil fatty acids, glycidyl methacrylate, -benzoquinone, and 2-methyl-imidazole mixed with tung oil and treated with tolylene diisocyanate, combined with benzoin methyl ether (26) 2. Glycerol-linseed oil-isophthalic acid alkyd reacted with isocyanate-containing prepolymer (formed by reaction of tolylene diisocyanate, -henzoquinone, 2-hydroxypropyl acrylate in ethyl acetate solution) using dibutyltin diacetate catalyst, combined with tung oil, synthetic varnish, and benzoin methyl ether (27) 3. Epoxidized... 

Burkus and Eckert (14) have studied the kinetics of the triethylamine catalyzed reaction of 2,6-tolylene diisocyanate with 1-butanol in toluene... 

Castor oil-urethane elastomers were prepared by reacting 2,4 tolylene diisocyanante, TDI, 80/20 2,4/2,6 TDI, or hexamethylene diisocyanate (HDI) with castor oil. The last reaction was rather slow and thus dibutyltin dilaurate, 0.001 gm per gm of HDI, was used as a catalyst. Since TDI hydrolyses significantly in the presence of trace amounts of water, DB grade castor oil from the Baker Castor Oil Company (NL Industries) was employed. 

The volatility of difunctional isocyanates (such as tolylene diisocyanates, hexamethylene diisocyanate, etc.) creates many environmental problems in the urethane industry. These difficulties can be overcome by preparation of NCO-terminated oligomers with low vapor pressure. One approach is the preparation of NCO-ter-minated oligomers by partial cyclotrimerization of difunctional isocyanates. Usually this is achieved by a multi-step process which includes also deactivation of the catalyst at a certain conversion. During our work on cyclotrimerization of isocyanates we found that cyclic sulfonium zwitterions are very active cyclotrimerization catalysts (2). Recently we found that cyclic sulfonium zwitterions under certain reaction conditions act as anionic initiators. This behavior of cyclic sulfonium zwitterions permits preparation of isocyanate oligomers containing isocyanurate rings by a one-step procedure, eliminating the deactivation step. 

The preparation was carried out in a dried 250 ml three-necked flask equipped with a nitrogen inlet, magnetic stirrer, reflux condenser, micro-dropping funnel and recording thermocouple. The reaction flask was immersed in a constant temperature bath (25°C) and 100 ml of the 2,4-tolylene diisocyanate (TDI) were placed into the flask. When constant temperature was reached in the flask, one ml of a solution of a catalyst in acetonitrile was added dropwise to the reaction mixture and the resultant mixture was intensively mixed for 4 hours. The reaction product was analyzed by GPC and the conversion was determined by the dibutylamine method. 

The effect of the concentration of the initiator and temperature on the final conversion of cyclotrimerization of 80/20 2,4- and 2,6-tolylene diisocyanate is depicted in Figs. 2 and 3. As can be seen, the extent of the reaction increases with an increase of the concentration of initiator and with decrease of temperature. The rate of addition of the initiator also plays an important role, as can be seen from Fig. 4. A typical distribution of oligomers is shown on the GP chromatogram shown in Fig. 5. The resulting NCO-term-inated oligomers are stable because the polymer formed from the initiator does not contain ionic or other catalytically active centers. 

The differential reactivity of the sterically hindered and unhindered isocyanate groups of tolylene-2,4-diisocyanate facilitates the stepwise conjugation of hapten (R) and protein (P) amino groups (Fig. 3, Rn 7). jd.jj -Difluoro-m,m -dinitrobenzene (DFDNB) reacts with numerous functionalities including primary and secondary amines, imidazoles, and phenols to yield mixtures of conjugated materials (Fig. 3, Rn 8). This reaction is apparently harder to control than the diisocyanate reactions, but it is much more versatile. 

When the less hindered 2,4-tolylene diisocyanate is reacted with a phospholene oxide catalyst linear oligomeric carbodiimides are obtained which have been reacted with a variety of nucleophiles to give poly(ureas), poly(acyl ureas), poly(formamidines) and poly-(guanidines) by addition across the N=C=N group. Also, reaction of the oligomeric carbodiimides with acrylic or methacrylic acid affords linear polymers, which can be further polymerized by free-radical type processes. Also, reaction of the carbodiimide oligomers obtained from 2,4-TDI with adipic acid in DMF produces a polyureid. ... 

As depicted in Scheme 4, the treatment of 1,4-diethynylbenzene with 2eq. of diphenylbromoborane (selective haloboration) and the subsequent reaction with leq. of tolylene-2,4-diisocyanate (phenylboration polymerization) gives the corresponding alternating copolymers. 

Polyethylene amine reacted with tolylene diisocyanate produces the NS-lOO membrane (NS stands for nonpolysaccharide). The reaction is carried out as follows ... 

A double-side adhesive tape was prepared using a mixture of a hydroxylterminated poly butadiene, a polyol, and an isocyanate compound containing an oxadiazinetrione ring 241 A compound suitable for sealing spaced glass panels comprises a reaction product of an unsaturated polymer with functional end groups with HTPB, a decane thiol adduct, and tolylene diisocyanate 242). 

The reactions of several diisocyanates with a large excess of 2-ethyl-hexanol have been reported by Bailey et al. [122]. Reactions were run in benzene with the extent of reaction being followed by loss of infrared absorption at 4.4 pm, characteristic for the isocyanate group. A sharp decrease in the rate of reaction of 2,4-tolylene diisocyanate and the 80 20 isomer ratio of tolylene diisocyanate at approximately 50% reaction was found. In contrast, 2,6-tolylene diisocyanate, 4,4 -diphenyImethane diisocyanate, p-phenylene diisocyanate and m-phenylene diisocyanate showed only a slight decrease in rate as the reaction proceeded. 

The decrease in rate after 50% reaction is quite apparent in the reaction of tolylene diisocyanate with the polyester at 29°C (Fig. 11). This change in rate illustrates the reduced reactivity of the 2-position isocyanate group, having steric hindrance from the ortho methyl substituent, as well as the lesser activating influence of a meta urethane substituent compared to a meta isocyanate substituent. An increase in reaction temperature favours the slow reaction more than the fast, as would be expected if differences in activation energy accounted for at least part of the difference in rates. Thus at 100°C there was little decrease in rate of reaction with TDI. In the case of 4,4 -diphenylmethane diisocyanate (Fig. 12), there was little change in rate after 50% reaction at any of the temperatures studied. 

Flexible Foams CO2 obtained in situ by the reaction of water with isocyanate has been the chief blowing agent for all commercially produced flexible urethane foams. The amount of water and tolylene diisocyanate (TDI) used determines foam density, providing most of the gas formed is used to expand the urethane polymer. Because water participates in the polymerization reactions leading to the expanded cellular urethane polymer, it has a very pronounced influence on the properties of foams. For better control of the foaming process most foam manufacturers employ distilled or deionized water (16). 

Nitrogen-containing phosphines (Figure 15) remain in the center of ligand synthesis. One reason for this may be in the solubility of the (unprotonated) amines in common organic solvents which allows the use of the methods of conventional organic synthesis. An additional aspect is in that amines can be further functionalized by several ways, for example as seen in 2.6 above. Another example is the reaction of 160 (diam-BINAP) with 2,6-tolylene diisocyanate affording an enantiopure polymeric... 

Suskind (1A9) described the formation of film-forming cationic urethane latices. The isocyanate-terminated prepolymer derived from either a polyester or polyether diol and tolylene diisocyanate was first chain-extended with an alkyIdiethanolamine to yield a relatively low molecular weight urethane capable of further chainextending reactions ... 

Complex mixtures of value as cationic binders for use in cathodic coatings have been derived from the reactions of substituted ureas, nonylphenol and formaldehyde. For example, the diketimine from diethylenetriamine and methyl isobutyl ketone (which served as a protective group in the first stsge of the process) by reaction with tolylene diisocyanate (semi-blocked with 2-ethylhexanol) afforded a urea. Treatment of the reaction mixture, presumably after removal of the ketonic group, with nonylphenol and aqueous formaldehyde gave a product which after solvent dilution was then reacted with bis-phenol A epoxy resin in diglyme solution (ref. 50). Such products can only be visualised as complex mixtures. 

Chemistry of Isocyanates. The most important industrial process for making isocyanates is by reacting a solvent slurry of the appropriate amine or its hydrochloride with phosgene. Solvents such as toluene and o-dichlo-robenzene have been used successfully. The following reaction occurs in the preparation of 2,4-tolylene diisocyanate, at present the one produced industrially in largest quantity ... 

In 2,4-tolylene diisocyanate several factors cause the reactivities of the two fimctional groups to differ. These can be discussed by considering the data in Table 2-3 on the reactivities of various isocyanate groups compared to that in phenyl isocyanate toward reaction with... 

Materials. 4-[(2-Hydroxyethyl)amino]-2-(hydroxymethyl)-4 -nitroazobenzene (T-AZODIOL) (10) was used as the NLO chromophore whose dipole moment is aligned transverse to the main chain. T-AZODIOL was synthesized via two step reactions as shown in Schemes 1 and 2. As shown, 3-(2-hydroxylamino)-benzylalcohol (DIOL) prepared from w-aminobenzyl alcohol with 2-chloroethanol was coupled with diazotized / -nitroaniline to give rise to T-AZODIOL. The details of the synthetic procedures were previously reported (8). 4-[N-(2-Hydroxyethyl)-N-methylamino]-3 -(hydroxymethyl)-azobenzene (AZODIOL) dye was the NLO chromophore monomer for preparing the polymer with NLO chromophore incorporated in the main chain. Detailed synthetic procedures of AZODIOL were previously reported (5), Commercially available 2,4-tolylene diisocyanate (TDI) and 4,4 -diphenylmethane diisocyanate (PDI) were used without further purification. The chemical structures of these monomers are shown in Figure 1. 

PH3 (2 to 4 atm) reacts with organic isocyanates, XC6H4NCO (X = H, p-Cl, P-NO2 [172] a77-CH3 [173]), in benzene in the presence of triethylamine or tributylamine to give tricarbamoyl-phosphanes, (XC6H4NHC(0))3P. Ethyl, octyl (in the presence of tripropylamine at lOO C and 340 atm), or 1-naphthyl isocyanate react analogously [173]. The reaction of 2,4-tolylene diisocyanate with PH3 is slow, and no definite product could be isolated. Phenyl isothiocyanate failed to react with PH3 under reaction conditions analogous to those for the isocyanates [172]. 

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