Maleated EPDM rubber

Ionic Thermoplastic Elastomer Based on Maleated EPDM Rubber... 

Zinc salt of maleated EPDM rubber in the presence of stearic acid and zinc stearate behaves as a thermoplastic elastomer, which can be reinforced by the incorporation of precipitated silica filler. It is believed that besides the dispersive type of forces operative in the interaction between the backbone chains and the filler particles, the ionic domains in the polymer interact strongly with the polar sites on the filler surface through formation of hydrogen bonded structures. 

Antony P., Bandyopadhyay S., and De S.K., Thermoplastic elastomers based on ionomeric polyblends of zinc salts of maleated polypropylene and maleated EPDM rubber, Polym. Eng. Sci., 39, 963, 1999. Weiss R.A., Sen A., Pottick L.A., and Willis C.L. Block copolymer ionomers. Thermoplastic elastomers possessing two distinct physical networks, Polym. Commun., 31, 220, 1990. 

The polarity of the matrix helps to improve the adhesion between melamine fiber and rubber because of the polar-polar interaction between the fiber and the matrix [118]. The presence of fiber in the absence of bonding system showed only marginal improvement in tensile strength (from 1.5 to 1.6 MPa) in the case of EPDM rubber-melamine hber composites. However, maleated EPDM rubber-melamine hber composites showed more than 50% improvement in tensile strength in the absence of the bonding system [118]. This is because of the presence of maleic anhydride groups, which imparts polarity to the mbber. 

A rapid technique for determining bound MAH content in maleated EPDM rubbers was established. It is based on the application of diffuse reflectance FTIR which permits the analysis of such products directly without any sample preparation other than removing unreacted monomer and initiator. The spectrum obtained also allows the evaluation of the rubber s relative oxidation extent. Baseline and band choices as well as calculation methods required are discussed. 12 refs. 

ST801 from EhiPont) is based on this technology of reactive blending of PA-66 with a maleated EPDM rubber. Similarly, the commercial ultra-tough polyamide (Capron BU50I from AlliedSignal) is based on a reactive blend of PA-6 and maleated EP rubber, which exhibits a high notched Izod impact (>900 J/m) even at —40°C. 

Adhesion of melamine fiber to rubber matrices Rajeev et al. found that the dry bonding system consisting of resorcinol, hexamethylene tetramine and hydrated silica effectively reinforces EPDM [64], maleated EPDM [118], and nitrile mbber matrices [119]. They observed increase in tensile... 

FIGURE 12.16 Plots of tan S versus temperature of maleated ethylene-propylene-diene monomer (EPDM) rubber-melamine fiber composites cured by using mixed cross-bnking system. (From Rajeev, R.S., Bhowmick, A.K., De, S.K., and Bandyopadhyay, S., J. Appl. Polym. Sci., 89, 1211, 2003. With permission.)... 

ID IQ 2D 2D-NMR 2h2o 2Q 3Q 9BEN A1 ABS AC ACM ACN AFM Al-CSM ALMA-i5 Al-m-EPDM AN AO APT ASTM ATR ATR-IR B/S BABA Two-dimensional Single-quantum One-dimensional Deuteron solid-state NMR Deuterated water Double-quantum Triple-quantum 9 borobicyclo [3, 3, 1] nonane Amide 1 Acrylonitrile-butadiene-styrene terpolymer Accelerator Acrylate rubber Acrylonitrile Atomic Force Microscopy Aluminium salt of chlorosulfonate polyethylene Allyl-rf5 methacrylate Aluminium salt of maleated EPDM Acrylonitrile 1-Allyl oxyoctane Attached Proton Test American Standards for Testing and Materials Attenuated total reflectance spectroscopy Attenuated total reflectance-IR spectroscopy Butadiene/styrene Back-to-back... 

Figure 7.12 depicts a model of chemical interactions proposed for a system of carbon black and maleated EPDM. There are two types of links. Hydrogen bonding and covalent bonding which is characterized by the attachment of filler particles to the chain. Because the rubber is crosslinked there is more opportunity for it to form interaction. 

The commercially successful super-tough nylon (e.g., Zytel ST801, DuPont ) is based on a reactive blending technology using PA-66 and a maleated (m-) EPDM rubber (Epstein 1979). The resulting PA-66/m-EPDM blend exhibits... 

EPDM, maleated Natural rubber see Poly(isoprene) cis Neoprene see Poly(l-chloro-l-butenylene) 236 1455... 

Effects of maleated ethylene-propylene diene rubber (EPDM) on the thermal stability of pure polyamides, and polyamide/EPDM and polyamide/poly (ethylene terephthalate) blends kinetic parameters and reaction mechanism/Zl. Vieira, V.L. Severgnini, D.J. Maasra MS. Soldi, E.A Pinheiro, AT.N. Pires and V. ScAAilPolymer degradation and stability (2001), 74 1 151-157. 

Typically a 50/50 blend of nitrile rubber and polypropylene is melt mixed with 5% maleated PP and 1% ATBN respectively and then cured with SnClj (0.5%). The resistance to hot oil swell (72 hr, 100°C) of NBR/PP blend is significantly better than that of EPDM/PP blend. Typical properties of the commercial dynamically cured NBR/PP blend (Geolast ) are compared with other such blends in Table 15.13. 

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