M-Phenylene dimaleimide

Maleimides Alkyl and aryl maleimides in small concentrations, e.g., 5-10 wt% significantly enhance yield of cross-link for y-irradiated (in vacuo) NR, cw-l,4-polyisoprene, poly(styrene-co-butadiene) rubber, and polychloroprene rubber. A-phenyhnaleimide and m-phenylene dimaleimide have been found to be most effective. The solubihty of the maleimides in the polymer matrix, reactivity of the double bond and the influence of substituent groups also affect the cross-fink promoting ability of these promoters [82]. The mechanism for the cross-link promotion of maleimides is considered to be the copolymerization of the rubber via its unsaturations with the maleimide molecules initiated by radicals and, in particular, by allyfic radicals produced during the radiolysis of the elastomer. Maleimides have also been found to increase the rate of cross-linking in saturated polymers like PE and poly vinylacetate [33]. 

When tested in other polymers, maleimides did not affect the rate of cross-linking in polydimethylsiloxane, polyisobutylene, and polyvinylchloride. In polyethylene, the addition of 5 wt.% of m-phenylene dimaleimide increased the G(X) from 1.8 to 7.2. In the polyvinylacetate the effect was even more pronounced the dose for gelation was reduced by about a factor of 50. Contrary to the cross-link enhancing effect found for m-phenylene dimaleimide, cross-linking was retarded in polyvinyl acetate by the addition of monomaleimides. When analyzing the mechanism of the reaction it was concluded that monomaleimides are not expected to affect cross-linking in saturated polymers. ... 

HVA-2 DuPont calcium carbonate N,N-m-phenylene dimaleimide agent Curative... 

Similar studies on ENR-50/EVA blends (50/50) containing N,N -m-phenylene dimaleimide (HVA-2) indicated that it is effective in enhancing the radiation-induced crosslinking of the ENR-50 phase when compared to EVA. The irradiation-induced crosslinking in ENR/EVA blends in the presence of HVA-2 has also unproved the compatibility of the blend. A possible mechanism of crosslinking for ENR-50 and EVA with HVA-2 has been proposed. ... 

Coagents should be used with the peroxide to obtain a satisfactory rate and state of cure. Commonly used coagents are TAC (triallyl cyanurate), TATM (triallyl trimelli-tate), HVA-2 (iV.M-m-phenylene-dimaleimide), di- or tri-methylacrylates, liquid high 1,2 polybutadiene, diaUyl phthalates, and others. The allylic types provide better process safety and are more effective in CSM. 

The base methacrylate monomers utilized were a polyethyleneglycol dimethacrylate (PEGMA - produced by Loctite), an ethoxylated bisphenol—A dimethacrylate (EBIPMA - produced by AKZO), a urethane methacrylated capped poly(butadiene acrylonitrile) polyol, and hydroxy-propyl methacrylate (HPMA - Rohm and Haas). The following maleimide capped monomer/prepolymers were examined N-phenyl maleimide (NPM), meta-phenylene dimaleimide (m-PDM), and a reaction product of methylenedi-aniline and excess methylenedianiline bismaleimide (P-MDA-2MDABM), sold by Rhodia Corp. under the tradename of Keramide... 

Figure 10 demonstrates, once again, the outstanding resistance in thermal aging with the use of the meta-phenylene-dimaleimide (m-PDM) additive as a comonomer with a urethane methacrylate monomer. The "neat" polymerized urethane methacrylate failed catastrophically within 1000... 

Khunova Viera, Liauw Christopher M., Kelnar Ivan, and Snauko Marian. Elimination of separation processes for post-consumer polyolefin waste Reactive blending using 1, 3-phenylene dimaleimide in presence of filler. Macromol. Mater. Eng. 294 no. 8 (2009) 502-509. 

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