Ethylene acrylate copolymers

Acrylate-ethylene copolymers have also been synthesized using the same tandem polymerization/hydrogenation methodology. Commercially, ethylene- 

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Polyacrylate elastomers find limited use in hydrauhc systems and gasket apphcations because of their superior heat resistance compared to the nitrile mbbers (219,220). Ethylene—acrylate copolymers were introduced in 1975. The apphcations include transmission seals, vibration dampers, dust boots, and steering and suspension seals. Further details and performance comparisons with other elastomers are given in reference 221 (see also Elastomers, SYNTHETIC-ACRYLIC ELASTOTffiRS). 

The homopolymers, which are formed from alkyl cyanoacrylate monomers, are inherently brittle. For applications which require a toughened adhesive, rubbers or elastomers can be added to improve toughness, without a substantial loss of adhesion. The rubbers and elastomers which have been used for toughening, include ethylene/acrylate copolymers, acrylonitrile/butadiene/styrene (ABS) copolymers, and methacrylate/butadiene/styrene (MBS) copolymers. In general, the toughening agents are incorporated into the adhesive at 5-20 wt.% of the monomer. 

The use of such an ethylene/acrylate copolymer provides a number of advantages. The ethylene portion of the copolymer is particularly well suited for adhering to the PE of the first polymer layer during fusion of the first polymer layer and the second polymer layer to one another. Further, the acrylate portion of the copolymer is particularly well suited for adhesion to bone cement, such as bone cement that includes poly(methyl methacrylate). Thus, using such a copolymer in the construction provides for ease of implantation in regard to a bearing designed for cement fixation. 

R. King, D.E. McNulty, and T.S. Smith, Composite prosthetic bearing constructed of polyethylene and an ethylene-acrylate copolymer and method for making the same, US Patent 7186364, assigned to DePuy Products, Inc. (Warsaw, IN), March 6, 2007. 

Another approach to improving the properties of starch-filled polyolefin materials involves the use of ethylene-acrylate copolymers in blends with PE.45 Addition of copolymers of ethylene with methyl acrylate, ethyl acrylate or butyl acrylate were shown to improve the properties of PE films, allowing for higher starch contents. Coextrusion of starch-containing films with outer layers incorporating oxidative pro-degradants has also been utilized 46 The inner layer can contain up to 40% starch the... 

Lundgren, A., Hjertberg, T., and Sultan, B.-A. 2007. Influence of the structure of acrylate groups on the flame retardant behavior of ethylene acrylate copolymers modified with chalk and silicone elastomer. J. Fire Sci. 25 287-319. 

Kramer, R.H., Blomqvist, P, Hees, P.V., and Gedde, U.W. 2007. On the intumescence of ethylene-acrylate copolymers blended with chalk and silicone. Polym. Deg. Stab. 92 1899-1910. 

Hermansson et al. carried out extensive investigations on the fire-retardant behavior of ethylene-acrylate copolymer modified with chalk and silicone elastomer.30 32 They have shown that incorporation of a silicone elastomer (at 5wt.%) and chalk filler (at 30wt.%) can greatly improve the flame-retardant properties of ethylene butyl acrylate formulations. The results show that, compared to the pure polymer, an increase in the LOI from 18 to 30, and a decrease in the peak heat release rate (PHRR) from 1300 to 330kW/m2 were observed. 

PP and PC are immiscible, thus excepting the exploratory use as a plastic paper, only the two ends of the concentration range have been explored, viz. addition of 5 wt% PP to PC (to improve processability of PC) [Dobkowski, 1980], or addition of <10 wt% of PC (to improve PP processability, enhance crystallinity and crystallization temperature, the appearance, modulus, and impact strength) [Liang and Williams, 1991]. For concentrations >10 wt% compatibilization is necessary. This is accomplished using ethylene-acrylic copolymer, cellulosics, PA, PVAc, or TPU [Goldblum, 1963, 1964] an acrylic elastomer, acrylic elastomer with PP-MA and either butyl mbber, or isobutene-isoprene mbber [Teijin Chem., 1982, 1983] SBR and EEA [Liu, 1984] MBS [Overton and Liu, 1984] or EVAc [Giles and Hirt, 1986],... 

The polyacrylate and ethylene-acrylic copolymers and one of the ethylene-propylene terpolymers (Nordel) were the best of the Intermediate temperature elastomers. Except for resistance to compression set, these materials were Inferior to the silicones in thermal stability as measured by their retention of tensile properties. The other EPDM compounds and butyl rubber were considerably inferior to the above-mentioned elastomers. It is not expected that the service life of the tested materials will be limited solely by their ability to resist hydrolytic degradation. The only caulking compositions which retained moderate physical integrity on thermal aging were the silicones. 

Vamac (N124) DuPont Ethylene-acrylic copolymer Base polymer... 

European Polymer Journal 33, No.3, March 1997, p.375-9 QUANTITATIVE IR SPECTROSCOPIC ANALYSIS OF ETHYLENE-ACRYLATE COPOLYMERS... 

IR spectroscopy was used for quantitative analysis of the composition of three ethylene-acrylate copolymers, i.e. ethylene-methyl acrylate, ethylene-butyl acrylate and ethylene-2-ethylhexyl acrylate copolymers. Based on a simple model which explicitly considered vibrational band intensities characteristic for CH and for C 0, copolymer composition could be derived from the ratio of C 0 and CH integrated absorbances with a precision of + or -3 mol %. It was not necessary to know the optical path length of the copolymer samples which were subjected to IR analysis as pressed films. 15 refs. 

Fluoroelastomers, silicone rubbers, butyl rubbers, ethylene-propylene terpolymer (Nordel), ethylene-acrylic copolymer (Vamac), and polyacrylate (Hycar 4054) were evaluated for the PS (preformed seal or gasket) compounds. 

This is accomplished using ethylene-acrylic copolymer, cellulosics, PA, PVAc, or TPU (Goldblum 1963, 1964) an acrylic elastomer, acrylic elastomer with PP-MA, and either butyl rubber or isobutene-isoprene rubber (Teijin Chem. 1982,1983) SBR and EEA (Liu 1984) MBS (Overton and Liu 1984) or EVAc (GUes and Hirt 1986). 

Baudouin, A.C., Devaux, J., and Bailly, C. (2010) Localization of carbon nanotubes at the interface in blends of polyamide and ethylene-acrylate copolymer. Polymer, 51,1341. 

FKMs are coextruded with lower-cost (co)polymers such as ethylene acrylic copolymer. 1 They can be modified by blending and vulcanizing with other synthetic rubbers such as silicones, EPR and EPDM, epichlorohydrin, and nitriles. Fluoroelastomers are blended with modified NBR to obtain an intermediate performance/cost balance. These blends are useful for underhood applications in environments outside the engine temperature zone such as timing chain tensioner seals. 

Figure 10. Kinetics and path way of reactive modification of the side group functionality of ethylene-acrylic copolymers in near-critical water at 300 C and 300 bar. [Adapted from ref 36]...

DuPont s Fusabond AEB-560D is a modified ethylene-acrylate copolymer for use in polyamides. It is claimed to be a cost-effective toughener, more effective than maleic anhydride terpolymers and usable at low temperatures, while improving mould flow, with less of an adverse effect on the flexural modulus. 

Ethylene-acrylate copolymers have been used as modifying agents to improve impact strength and compatibility of other polymers [24, 25]. 

Acrylic polymers have been used as alternatives to nitrile rubbers in some hydraulic and gasket applications because of their excellent heat-resistance properties (236,237). Ethylene-acrylate copolymers have been used as transmission seals, vibration dampeners, dust boots, and steering and suspension seals (238). 

A. E. Hirsch, Dynamic Characteristics of Fluoroelastomers and Ethylene/Acrylic Copolymers, Bulletin EA-530.602, DuPont Polymers, Stow, Ohio, 1980. 

In a similar approach, ethylene/acrylate copolymers were analyzed. Figure 26 shows the separation of ethylene/methyl acrylate copolymers by high-temperature gradient HPLC. In this case a silica gel Perfectsil 300 was used as the stationary phase. The mobile phase was a gradient of decaline-cyclohexanone [118]. 

Polyethylene copolymers such as EVA (ethylene-vinyl acetate copolymer), ethylene-acrylate copolymers, or ionomer copolymers are also damaged by UV light. With increasing vinyl acetate (VAC) content, weathering resistance in EVA increases. 

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