P Ethylene-propylene copolymer

Sivaram, S. and Singh, R. P. Degradation and Stabilization of Ethylene-Propylene Copolymers and Their Blends A Critical Review. Vol. 101, pp. 169-216. 

Figure 19 (a) Peak melting temperature as a function of the branch content in ethylene-octene copolymers (labelled -O, and symbol —B (symbol, ) and -P (symbol, A) are for ethylene-butene and ethylene-propylene copolymers, respectively) and obtained from homogeneous metallocene catalysts show a linear profile, (b) Ziegler-Natta ethylene-octene copolymers do not show a linear relationship between peak melting point and branch content [125]. Reproduced from Kim and Phillips [125]. Reprinted with permission of John Wiley Sons, Inc. 

Patri, M., Hande, V. R., Phadnis, S. and Deb, P. C. 2004. Radiation-grafted solid polymer electrolyte membrane thermal and mechanical properties of sulfonated fluormated ethylene propylene copolymer (FEP)-graft-acrylic acid membranes. Polymers for Advanced Technologies 15 622-627. 

Phadnis, S., Patri, M., Chandrasekhar, L. and Deb, P. C. 2005. Proton-exchange membranes via the grafting of styrene and acrylic acid onto fluorinated ethylene propylene copolymer by a preirradiation technique. III. Thermal and mechanical properties of the membranes and their sulfonated derivatives. Journal of Applied Polymer Science 97 1418-1425. 

Mean-square unperturbed dimensions a and their temperature coefficient, d tin 0) I d T, are calculated for ethylene-propylene copolymers by means of the RIS theory. Conformational energies required in the analysis are shown to be readily obtained from previous analyses of PE and PP, without additional approximations. Results thus calculated are reported as a function of chemical composition, chemical sequence distribution, and stereochemical composition of the PP sequences. Calculations of 0 / nP- are earned out using ( ) r r2 = 0.01, 1.0, 10.0, and 100.0, (ii) p, = 0.95, 0.50, and 0.05, liii) bond length of 153 pm and bond angles of 112°for all skeletal bonds, iv) = 0 and 10°, and (v) statistical weight factors appropriate for temperatures of 248, 298, and 348 K. Matrices used are ... 

From Mark s RIS model for ethylene-propylene copolymers (J. Chem. Phys. 1972, 57, 2541) it is determined that P(t) = 0.380, P g+) = 0.014, and Pig") = 0.606 in 2,4-dimethylhexane (2,4-DMH). Using this RIS model, furthermore, for all the branched alkanes considered whose isopropyl groups are separated by at least one methylene carbon from the next substituted carbon and the RIS model developed by Asakura et at. (Makromol. Chem, 1976, 177, 1493) for head-to-head polypropylene to treat 2,3-dimethyl pentane, AS s are calculated for a large number of branched alkanes. The agreement between the observed and the calculated nonequivalent 13C NMR chemical shifts is quite good, including the prediction that separation of the isopropyl group from the next substituted carbon by four or more methylene carbons removes the nonequivalence. 

Radioisotope detection of P, 14C, and Tc was reported by Kaniansky et al. (7,8) for isotachophoresis. In their work, isotachophoretic separations were performed using fluorinated ethylene-propylene copolymer capillary tubing (300 pm internal diameter) and either a Geiger-Mueller tube or a plastic scintillator/photomultiplier tube combination to detect emitted fi particles. One of their reported detection schemes involved passing the radiolabeled sample components directly through a plastic scintillator. Detector efficiency for 14C-labeled molecules was reported to be 13-15%, and a minimum detection limit of 0.44 nCi was reported for a 212 nL cell volume. 

It may be interesting, in connection with the ethylene/propylene copolymers mentioned above, to present here some homogeneous Ziegler-Natta catalysts formed by soluble complexes of titanium and magnesium chlorides with alkyl phosphates as catalyst precursors and alkylaluminium compounds as activators (TiCl4)x.(MgCl2)r [0=P(0Bu)3]3-A1(/-Bu)3 and Cl3TiOMgCl-[0 = P(0Bu)3]3- A1(z -Bu)3 (Al/Ti molar ratio of ca 10 1). These catalysts have been used for random ethylene/propylene copolymerisation [73],... 

A statistical ethylene-propylene copolymer with the ratio of 4 ethylene units to 3 propylene units (E.P. Rubber) has approximately the same degree of branching as the trimethyl nylon 6/6 of Table II. 

Grady, B.P. Goossens, J.G.P. Wouters, M.E.L. Morphology of zinc-neutralized maleated ethylene-propylene copolymer ionomers structure of ionic aggregates as studied by x-ray absorption spectroscopy. Macromolecules 2004, 37, 8585. 

Bly,R.M., Kiener,P.E., Fries,B.A. Near-infrared method for analysis of block and random ethylene-propylene copolymers. Anal. Chem. 38,217-220 (1966). 

Corish,P. J., Small, R.M.B., Wey,P.E. Determination of ethylene-propylene copolymer composition by infrared analysis. Anal. Chem. 33, 1793-1794 (1961). 

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