4-4 diamino diphenyl methane

The epoxy resin formed by tetraglycidyl 4,4 -diamino diphenyl methane and 4,4 -diamino diphenyl sulfone was characterized by dynamic mechanical analysis. Epoxy specimens were exposed to varying dose levels of ionizing radiation (0.5 MeV electrons) up to 10,000 Hrads to assess their endurance in long-term space applications. Ionizing radiation has a limited effect on the mechanical properties of the epoxy. The most notable difference was a decrease of approximately 40°C in Tg after an absorbed dose of 10,000 Mrads. Sorption/desorption studies revealed that plasticization by degradation products was responsible for a portion of the decrease in Tg. 

Asahi Chemical Industries KK claim the unique compound 2-fluoro-4,4 -diamino diphenyl methane, used as a monomer of very high heat resisting resins, is easily obtained by the ECF of 4,4 -diaminodiphenyl methane [97]. 

Using simple laboratory equipment, it is possible to detect variations of the density of the order of 1 kg m-3 therefore, density measurements would be useless for diglycidyl ether of bisphenol A and diamino diphenyl methane (DGEBA-DDM), because both components have close Ma values. They would be moderately sensitive for unsaturated polyesters of maleate/ phthalate (1/1) of propylene glycol crosslinked by styrene (36 wt%), and relatively sensitive for DGEBA cured by diamino diphenyl sulphone (DDS) or phthalic anhydride (PA), for which relative variations of the molar ratio y of about 5% could be detected. In certain cases, where some comonomer (PA or styrene) can be lost by evaporation during the cure, density measurements can constitute a simple and efficient method of control way (e.g., for non-filled materials). 

The mechanisms of radiation damage and effects of hardeners were studied recently by pulse radiolysis [89], The epoxy resins require a relatively large amount of curing agents (hardeners), most of them are aromatic and aliphatic amines such as diamino diphenyl methane or triethylene tetramine. On the basis of the emission spectra and kinetic behavior of excited states observed, the radiation resistance of aromatic and aliphatic amine curing epoxy resin was explained by internal radiation protection effects due to energy transfer. 

According to a report presented by Fu et al. [180], the influence of POSS-triol on epoxy-amine reaction depends mostly on the magnitude of AT (Tg -Tc) used. Since Tg for epoxy cured with linear aliphatic diamine—2-methyl-1,5-pentadiamine (MPDA)—was higher than the Tg of the same epoxy cured with diamine-terminated polypropylene oxide (PPO), when cured at the same temperature, epoxy-cured MPDA showed a greater improvement in the value of Tg. Moreover, the addition of POSS-triol in tetraglycidyl diamino diphenyl methane (TGDDM) cured with MPDA also increased the rubbery plateau modulus (Fig. 6). 

Scheme 1.6. Aromatic amine curing agents DDS, 4,4 -diamino diphenyl sulfone and DDM, 4,4 -diamino diphenyl methane.

Trippel-Schulte, P., Zeiske, J., and Kettrup, A., Trace analysis of selected benzine and diamino diphenyl methane derivatives in urine by means of liquid chromatography using precolumn sample preconcentration, UV and electrochemical detection, Chromatographia, 22, 138-146, 1986. 

Amines such as diethylene triamine, isophorone diamine, and 4,4-diamino-diphenyl methane, on the other hand, induce cold curing with formation of poly-j3-hydroxypropylamine structures ... 

Figure 3.5 Programmed TGA to 800 °C under nitrogen at 5 °C/min of stoichiometric thermoset resins based on DGEBA. DDM resin cured with diamino diphenyl methane, mPDA resin cured with m-phenylene diamine, pPDA resin cured with p-phenylene diamine, mXDA resin cured with weto-xyylene diamine, AN the stoichiometric thermoplastic reaction product of DGEBA and aniline (included for comparison). Reproduced with permission from T. Dyakonov, P.J. Mann, Y. Chen and W.T.K. Stevenson, Polymer Degradation and Stability, 1996,...

DDM Resin cured with diamino diphenyl methane... 

DDM = Diamino diphenyl methane For the mixtures of epoxy monomers, 1 1 mol ratio was used. Stoichiometric amounts were used in all cases. From differential scanning calorimetry method measurements (10 °C/min). Maximum of the loss modulus from dynamic mechanical thermal analysis measurements. a relaxation peak of the loss factor. Reproduced with permission from M. Sponton, L.A. Mercado, J.C. Ronda, M. Galia and V. Cadiz, Polymer Degradation and Stability, 2008, 93, 2025. 2008, Elsevier [22] ... 

A novel triglyceride-based a, p-unsaturated ketone, obtained by photoperoxidation from high oleic sunflower oil, can be cross-linked with diamino diphenyl methane through the aza-Michael addition reaction. The reaction of p-toluidine with either enone-containing methyl oleate or epoxidised methyl oleate, produces an alternative to amine-cured epoxidised vegetable oil thermosets. ... 

In order to verify the possibility of the contribution of these reactions to the change in the mechanical properties, some quantities of 4,4 -diamino diphenyl methane (MDA) were incorporated into the polymeric material, so to obtain an equivalent quantity of -NH2 groups equal to 0.02 g / 100 g of a linear PU (equal to the excess initial concentration of -NCO groups corresponding to I = 110). Thin films of PUs with MDA about 0.5 mm thick were obtained by evaporation from solution at 60°C as described elsewhere [17]. 

Glycidyl amine resins are prepared hy reaction of epichlorhydrin with either primary diamines, monoamines or aminophenols. Each primary amine gives rise to two epoxide substituents. The reaction again involves two steps reaction of the epichlorhydrin with an active hydrogen to form the chlorohydrin, followed by ring closure with sodium hydroxide to generate the new epoxide. The common glycidyl amines are the reaction products of epichlorhydrin with diamino diphenyl methane and with p-aminophenol. 

For vulcanization either amines or peroxides may be used. A typical amine is 4,4 -methylene dianiline (4,4 -diamino diphenyl methane) which is now used in conjunction with an accelerator such as diphenyl guanidine or diorthotolylguanidine. The properties of these rubbers have been reviewed (Hagman et al., 1976). 

Oxidation products depending on the hardener structure. For example, diamino diphenyl methane (4.53) undergoes the strongest yellowing of all amines, and produces an unknown chromophore absorbing at 615 nm, according to the mechanism ... 

One of the driving forces behind recent developments in the synthesis and characterization of new acids is the requirement to replace mineral acids by reagents and catalysts that will lead to reduction in waste, in other words to an improved atom economy. Thus, HCl used in the synthesis of diamino diphenyl methane, an intermediate in polyurethane production, can be replaced by a silico-aluminate catalyst in which the acid sites of the zeolite are accessible through the external surface. Less conventionally, simple aromatic hydrocarbons can be nitrated using 60-70% nitric acid in the presence of the strong Lewis acids, lanthanide-perfluoroalkane sulfonic acid salts, such as the ytterbium(lll) compounds (VI) and... 

Carbon nanotubes have been shown to increase the rate of the curing reaction of epoxies (Yin et al. 1993 Puglia et al. 2003). This effect arises from the surface chemistry of the nanotubes (Shaffer and Sandler 2006). However, barium titanate nanoparticles did not affect tbe curing behavior of epoxy cured using diamino diphenyl methane (DDM) (Chandradass and Bae 2008). 

Scheme 33a Synthesis of N,N -Tetraglycidyloxyl diamino diphenyl methane (TGDDM).

Polyimide Synthesised from (4,4 -Hexafluoroisopropylidene) diphthalic Dianhydride (DTG) and an Unfluorinated Polyamide 4,4 -diamino diphenyl Methane (PIF )... 

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