Ethylene-propylene monomer grafting

Studies by Ravikumar et al. (2005) show that PTT/ethylene propylene diene monomer (EPDM) blends are irrmriscible, which is supported by an increase in the free volume and constancy in crystallinity of PTT with increasing EPDM content and the use of ethylene propylene monomer grafted maleic anhydride as compatibilizer is found to produce significant improvement in properties by modifying the interface of the blends. 

ATBN - amine terminated nitrile rubber X - Flory Huggins interaction parameter CPE - carboxylated polyethylene d - width at half height of the copolymer profile given by Kuhn statistical segment length DMAE - dimethyl amino ethanol r - interfacial tension reduction d - particle size reduction DSC - differential scanning calorimetry EMA - ethylene methyl acrylate copolymer ENR - epoxidized natural rubber EOR - ethylene olefin rubber EPDM - ethylene propylene diene monomer EPM - ethylene propylene monomer rubber EPR - ethylene propylene rubber EPR-g-SA - succinic anhydride grafted ethylene propylene rubber... 

This means a decrease of the diffusion distance of the polycondensate chains to the rubber interface by a factor of 10 and an increase of the interface by a factor of 10 , that is, the rate of interfacial reactions is dramatically enhanced. In the case of PA-6/ EPM-g-MA blends (EPM-g-MA, ethylene and propylene monomer grafted with maleic anhydride) the reaction is so fast that as interfaces are created upon melting they become immediately covered with PA-6 chains, causing a quick reduction of the interfacial tension and preventing coalescence, which induces a further refinement of the dispersed phase. 

EPM-g-MA Ethylene and propylene monomer grafted with maleic... 

Whilst the ASA materials are of European origin, the AES polymers have been developed in Japan and the US. The rubber used is an ethylene-propylene terpolymer rubber of the EPDM type (see Chapter 11) which has a small amount of a diene monomer in the polymerisation recipe. The residual double bonds that exist in the polymer are important in enabling grafting with styrene and acrylonitrile. The blends are claimed to exhibit very good weathering resistance but to be otherwise similar to ABS. 

FIGURE 13.2 Calculated relation between the solubility parameter and glass transition temperature (Jg) for a variety of ethylene-propylene copolymers (EPMs) grafted with polar monomers the window for rubbers with an oil resistance similar to or better than hydrogenated acrylonitrile-butadiene copolymer (NBR) (20 wt% acrylonitrile) is also shown. 

Radiation Treatment NVP, 2-hydroxyethylmethacrylate (HEMA), and acrylamide (AAm) have been grafted to the surface of ethylene-propylene-diene monomer (EPDM) rubber vulcanizates using the radiation method (from a Co 7 source) to alter surface properties such as wettability and therefore biocompatibility [197]. Poncin-Epaillard et al. [198] have reported the modification of isotactic PP surface by EB and grafting of AA onto the activated polymer. Radiation-induced grafting of acrylamide onto PE is very important... 

Graft Copolymers with High Backbone-Polymer Content. Work on VC/PE graft copolymers of this type led to a process (10) now being tested on pilot-plant scale. Its industrial application is being considered. The process is also applicable to other backbone polymers that are sufficiently swelled by this monomer. Most grades of ethylene-propylene... 

The polymerization reaction in aqueous suspension of vinyl chloride in the presence of an ethylene-propylene saturated elastomer occurs with the formation of poly (vinyl chloride) homopolymer and rubber-poly (vinyl chloride) grafted copolymers. The first grafting reaction proceeds as far as diffusion of the monomer inside the particles in suspension is possible afterwards, some chain branching of grafted PVC is possible. Under our experimental conditions the amount of grafted rubber does not exceed 60% of the initial rubber and is little influenced by the type of initiator used. 

Acrylonitrile-Ethylene/Propylene-Styrene Copolymer AES is a terpolymer obtained by grafting styrene-acrylonitrile copolymer to ethylene-propylene or ethylene-propylene-diene monomer rubber. Similar to ABS except with improved weathering resistance. 

H5V was used as grafting monomer for atactic polypropylene, ethylene/propylene copolymer, ethylene/vinyl acetate copolymer, poly(methyl acrylate) and poly(methyl methacrylate) (32). In all cases, grafting was achieved in chlorobenzene with ditertiarybutyl peroxide as the initiator. Up to now, we have not succeeded in grafting 2H5P under the same conditions onto these polymers. 

Weather-Resistant Grafts of Vinyl Monomers to Ethylene-Propylene-Diene-Monomer (EPDM) and Polyacrylates... 

Recent findings indicated that this drawback can be overcome by using particular reinforcing agents, i.e. graft copolymers obtained by modifying saturated or low-unsaturated elastomers such as ethylene-propylene (EP) or ethylene-propylene-diene monomer (EPDM) rubbers and acrylic elastomers (9-16). 

The experimental data on monomer grafting to homopolyolefins (polypropylene (PP), polyethylene (PE), copolymers of ethylene and propylene (EPR)) make it possible to predict the course of the main process and associated reactions depending on the factors mentioned. Considering that the grafting rate can be described by a kinetic equation of first order with respect to the monomer concentration (3), it seems possible to qualify the level of functionalization. 

Blends of PET/HDPE have been treated previously in the literature [157, 158]. These are immiscible, but the addition of compatibilizers improves the mechanical properties of the blend, such as styrene-ethylene/butylene-styrene (SEBS) and ethylene propylene diene monomer (EPDM) [157], MAH [158], Poly(ethylene-stat-glycidyl metha-crylate)-graft-poly(acrilonitrile-stat-styrene) (EGMA), poly (ethylene acrylic acid), and maleated copolymers of SEBS, HDPE, ethylene-propylene copolymer (EP). The addition of compatibilizers modifies the rheological properties of blends of PET with HDPE, in such a way that increases in viscosity are observed as the component interactions augment. Changes in crystallization of PET were evaluated in blends with Polyphenylene sulfide (PPS), PMMA, HDPE aromatic polyamides, and copolyesters [159]. 

A general scheme for the production of such functionalized polymers can be presented as follows The polymer support (polyethylene (PE), polypropylene (PP), polystyrene (PS), polytetrafluoroethylene (FIFE), ethylene-propylene copolymers (CEP), etc.) are subjected to mechanical, chemical, radiation-chemical ( -irradiation or with accelerated electrons) or high-frequency (HF), UV-irradiation treatment with a subsequent grafting of the appropriate monomers ... 

Pasbakhsh, R, Ismail, FI., Ahmad Fauzi, M. N., and Abu Bakar, A. 2009. Influence of maleic anhydride grafted ethylene propylene diene monomer (MAH-g-EPDM) on the properties of EPDM nanocomposites reinforced by halloysite nanotubes. Polymer Testing 28 548-559. 

Stability (see Table 12.2). R talc is effective with ethylene propylene diene monomer (EPDM) and ethylene propylene rubbers (EPR) but not as effective with metallocene elastomers containing TPOs. Recently, Clark [11] presented evidence of improvements in scratch and mar resistance when talc is grafted to TPO. The need for higher performance materials will drive the development of new surface modification technologies [3]. 

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