Reinforced poly elastomers

Bokobza, L. Burr, A. Garnaud, G. Perrin, M. Pagnotta, S. (2004) Fibre Reinforcement of Elastomers Nanocomposites Based on Sepiolite and Poly(hydroxyethyl acrylate). Polym. Int. Vol.53, N0.8, pp.1060-1065, ISSN 0959-810 Bonduel, D. Mainil, M. Alexandre, M. Monteverde, F. Dubois, P. (2005) Supvported Coordination Polymerisation A Unique Way to Potent Polyolefin Carbon Nanotube Nanocomposites. Chem. Commun. Vol.l4, No.6, pp.781-783 Bruckner, S. Meille, S. Petraccone, V. Pirozzi, B. (1991) Polymorphism in Isotactic Polypropylene. Prog. Polym. Sci. 16, No.2-3, pp.361-404 Bryning, M. Islam, M Kikkawa, J. Yodh, A. (2005) Very Low Conductivity Threshold in Bulk Isotropic Single-Walled Carbon Nanotube-Epoxy Composites. Ado. Mater. Vol.17, N0.9, pp.1186-1191... 

Lin and co-workers [47] reinforced PU elastomers with an entirely rigid aromatic polyamide, poly(w-phenyleneisophthalamide). The block copolymers formed exhibited glass transition temperatures (Tg) under 0 °C. Such block copolymers have improved reinforcing affect as shown by both their tensile strength and elongation when compared with the virgin PU. 

Considerable reinforcement of elastomers, including PDMS, can be achieved in this way. Because of the nature of this in-situ precipitation, the particles are well dispersed and essentially unagglomerated. The particles are also relatively monodisperse, with almost all of them having diameters in the range 200 - 300 A. Poly(dimethylsiloxane) has also been reinforced with clay-like materials (109). 

Light-colored hllers are not as effective as carbon black in reinforcing poly-sulhde elastomers. It is very important that low pH hllers, such as clay, be avoided as these will retard the rate of vulcanization, as may be seen in Table 11.8. 

It appears (Table 11) that the reinforcing ability exhibited by a HAF carbon black in polybutadiene or EPR is much lower after its surface has been previously modified by grafting of polystyrene M). Such results cannot, however, be associated with the elastomer s incompatibility towards the polystyrene grafts since poly-isoprene-grafted carbon blacks yield similar conclusions 65). 

This approach has been used to form ceramic-like phases in a wide variety of polymers. The one which has been studied the most in this regard is poly(dimethylsiloxane) (PDMS), the semi-inorganic polymer featured extensively in Chapter 4. This is due to PDMS being in the class of relatively weak elastomers most in need of reinforcement, and being capable of easily absorbing the precursor materials generally used in the sol-gel process. 

Fu FS, Mark JE (1988) Elastomer reinforcement from a glassy polymer polymerized in-situ. J Poly Sci Part B Poly Phys 26(ll) 2229-2235... 

Organic matrices are divided into thermosets and thermoplastics. The main thermoset matrices are polyesters, epoxies, phenolics, and polyimides, polyesters being the most widely used in commercial applications (3,4). Epoxy and polyimide resins are applied in advanced composites for structural aerospace applications (1,5). Thermoplastics Uke polyolefins, nylons, and polyesters are reinforced with short fibers (3). They are known as traditional polymeric matrices. Advanced thermoplastic polymeric matrices like poly(ether ketones) and polysulfones have a higher service temperature than the traditional ones (1,6). They have service properties similar to those of thermoset matrices and are reinforced with continuous fibers. Of course, composites reinforced with discontinuous fibers have weaker mechanical properties than those with continuous fibers. Elastomers are generally reinforced by the addition of carbon black or silica. Although they are reinforced polymers, traditionally they are studied separately due to their singular properties (see Chap. 3). 

Amoco Resin 18. [Amoco] Poly-a-methylstyrene extrusion and nudding process aid in ABS, PVC, CPVC, and semirigid vinyl, thermoplastic urethanes, molded rubbers, and thermoplastic elastomers modifier and reinforcer in adhesives, thermoplastic powd. coatings, hot-n t coatings. 

Ito et al (16) used combinatorial bioengineering methods to produce new biomaterials based on amino acids, nucleic acid, and non-natural components. In a different way, Silvestri et al (7) produced biomaterials by combining enzymes with synthetic polymers some examples were combinations of a-amylase with poly(vinyl alcohol), poly(ethylene glycol), and poly(hydroxyethyl methacrylate). Jong (9) used soy protein as a reinforcement material in elastomers and observed an increase in the rubber modulus. 

In the simplest approach to obtaining elastomer reinforcement, some of the organometallic material is absorbed into the cross-linked network, and the swolloi sarrqrle placed into water containing the catalyst (typically a volatile Ime such as ammonia or ethylamine). Hydrolysis to form the desired silica-like particles proceeds rapidly at room temperature to yield the order of 50 wt % filler in less than an hour. - - The polymer most studied in this regard is hydroxyl-terminated poly(dimethylsiloxane) (PDMS), of repeat unit [-Si(CH3)20-]. 

Further, the effect of the reinforcement of carbon nanotubes on the properties of the recycled PET/PEN blends has been investigated [83]. Two types of functional elastomers, a terpolymer of ethylene ethyl acrylate-maleic anhydride and a terpolymer of ethylene-methyl acrylate-glycidyl methacrylate, have been used to ensure the miscibility between poly(ethylene terephthalate) and poly(ethylene naphthalate) during the preparation of the blends. 

Table 37 3. Characteristic Properties of Some Reinforced General Purpose Elastomers, NR, Natural Rubber IR, Synthetic cis l,4 poly(isoprene) BR, Poly (butadiene) (Li type) TPR, trans poly(pentenamer) SBR, Styrene j Butadiene Rubber (Emulsion Grade with 40% Styrene) EPDM, Ethylene j Propylene Diene Rubber...

N nylon, PO polyolefin, elastomer, TPU thermoplastic urethane, GF glass fiber, NBR nitrile rubber, MAH maleic anhydride, EPR ethylene-propylene copolymer, l ionomer, M- mineral, ABS acrylonitrile-butadiene-styrene copolymer, PPE poly (phenylene ether), R reinforcement, PTFE poly(tetrafluoroethylene), CF° carbon fiber, PEBA poly(etherblockamide), S silicone, RIPP D reaction injection molding plastic, and ASA acrylate-styrene-acrylonitrile copolymer. 

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