Diphenyl-methane diisocyanate

NR can be cross-linked by a blocked diphenyl methanes diisocyanate to produce urethane crosslinks. The cross-linking agent dissociates into two quinonedioxime molecules and one diphenyl methane diisocyanate. The quinone reacts with the rubber via a nitroso group and forms cross-links via diisocyanato group. The performance of this system in NR is characterized by excellent age resistance and outstanding reversion resistance. 

Figure 7. Dependence on the gel fraction, molar ratio of OH to NCO groups, rjj, for poly(oxypropylene) (POP) triol -4,4 -diphenyl-methane diisocyanate (HDI) net-...

Tanser AR, Bourke MP, Blandford AG Isocyanate asthma respiratory symptoms caused by diphenyl-methane-diisocyanate. Thorax 2 -. 

PBX-9011-02 HMX 90 Sc Estane (Trademark of B.F, Goodrich Chemical Co for polyester urethane of adipic acid 1,4-butanediol, diphenyl methane diisocyanate) 10%... 

International Isocyanate Institute. 1990. Biodegradation of toluene diisocyanate and diphenyl methane diisocyanate. EPA/OTS doc 86-870000646. 

Rosthauser et al. (4) used l-methyl-3-phospholene-l-oxide to prepare and isolate oligomeric diisocyanates containing dicarbodiimides using 4,4 -diphenyl-methane diisocyanate. Diisocyanates containing dicarbodiimides were also prepared by Takahashi et al. (5) using 3-methyl-l-phenyl-2-phospholene-l-oxide as the reaction catalyst. 

Abbreviations PTMA poly(tetramethylene adipate) PEA poly(ethylene adipate) MDI diphenyl-methane diisocyanate BD butane diol PAN polyacrylonitrile Ar polyarylate OBU oligobutadiene-urethane... 

Sulfo group-containing poly(amide imide) semipermeable membrane 35 from trimellitic anhydride sodium 3,5-dicarboxybenzenesulfonate, and 4,4 -diphenyl-methane diisocyanate have been prepared 90>. A 110 p-thick membrane gave water permeation 5601/m2 day and salt rejection 99.0% (0.5% aqueous NaCl solution, 25 °C, 42 kg/cm2), while a trimellitic anhydride-4,4 -diphenylmethanediisocyanate copolymer membrane gave 30 1/m2 day and 98.2%, respectively. 

The dynamic mechanical properties of three epoxy resins cured with diphenyl-methane diisocyanate (MDI) are shown in Fig. 15. Since these resins consist of many bulky cyclic structures, Tg (a-dispersion) is above 200 °C and the transition region is wide. In the DEN 431 —L-MDI resin, Tg is higher than 300 °C. The resin is expected to be highly heat-resistant51). 

Dozens of isocyanate functional compounds have been synthesized, but only a few find much use in urethane structural adhesives. The choices are largely dictated by a combination of performance, price, and safety considerations. Most of the materials used in adhesives are derived from the aromatic isocyanates, toluene diisocyanate (TDI) and 4,4 -diphenyl-methane diisocyanate (MDI). 

The IPNs prepared were composed of a rubbery polyurethane and a glassy epoxy component. For the polyurethane portion, a carbodiimide-modified diphenyl-methane diisocyanate (Isonate 143L) was used with a polycaprolactone glycol (TONE polyol 0230) and a dibutyltin dilaurate catalyst (T-12). For the epoxy, a bisphenol-A epichlorohydrin (DER 330) was used with a Lewis acid catalyst system (BF -etherate). The catalysts crosslink via a ring-opening mechanism and were intentionally selected to provide minimum grafting with any of the polyurethane components. The urethane/epoxy ratio was maintained constant at 50/50. A number of fillers were included in the IPN formulations. The materials used are shown in Table I. 

Isonate 143L Carbodiimide-modified diphenyl methane diisocyanate, functionality=2.1 Upjohn Co. 

DIPHENYLMETHANEDIAMINE see MJP750 4,4 -DIPHENYLMETHANEDIAMINE see MJQOOO DIPHENYL METHANE DIISOCYANATE see MJP400 4,4 -DIPHENYLMETHANE DIISOCYANATE see N5P400... 

A Polyester and a Polyurethane. A segmented polyether-polyurethane sample (UET46-1) was synthesized in one step from 4-4 diphenyl methane diisocyanate, 1-4 butanediol and poly(tetra-methylene ether)glycol ... 

Richter and Macsoko (1980) describe the chemoviscosity of a reactive polyurethane (4,4 -diphenyl methane diisocyanate, polyester triol and dibutyltin dilaurate catalyst) reasonably well by the following model ... 

Vibrathane B605 A prepolymer based on diphenyl-methane diisocyanate (MDI) and poly-tetramethylene glycol 3.02 1333 Uniroyal... 

Thus, from high MW diols (MW = 1000-4000 daltons) polyethers (polyalkyleneoxides, polytetrahydrofuran (PTHF)), polyesters, polycarbonates (PC), polybutadienes, etc., by the reaction with diisocyanates [toluene diisocyanate (TDI), or pure diphenyl methane diisocyanate (MDI)], high MW linear polyurethanes are obtained (no crosslinking), with high elasticity (polyurethane elastomers, spandex fibres, some adhesives and sealants, etc). 

While the use of plastics in refirigerators is well established, product development has led to replacement of some of the conventional plastics with newer ones of improved properties. For insulation rigid polyurethane foam has, on the whole, replaced fiberglass in cabinets and doors. In this application, diphenyl-methane diisocyanate (MDI), which has lower vapor pressure than toluene diisocyanate (TDI), is now preferred. 

The most important uses for aniline today are the production of 4,4 -diphenyl-methane diisocyanate (MDI) and chemicals used in rubber processing, especially as vulcanization accelerators or antioxidants. Additional applications, which were dominant in former times, e.g. dyestuffs, plant protection agents and raw materials for fibers, complete the range of aniline applications. 

---