Ethylene-butene copolymers

Styrene-Butadiene-Styrene Block Copolymers. Styrene blocks associate into domains that form hard regions. The midblock, which is normally butadiene, ethylene-butene, or isoprene blocks, forms the soft domains. Polystyrene domains serve as cross-links. 

Aluminum foil Ethylene-butene copolymer—polyiso- 0.9... 

Multilayered materials owe their properties and behavior to the properties of and the interactions between the components (5). Each of the two or more components contributes its particular property to the total performance of the multilayered material. For example, in Pouch 1, Table II, the aluminum foil provides high oxygen and water vapor permeability resistance, poly (ethylene terephthalate) provides structural strength and stiffness, and the ethylene-butene copolymer provides a heat sealable layer. If the components of the multilayered materials interact then the whole would be something different than the sum of its parts. In other words, the properties of the components of the multilayered materials are not independent of one another but rather are interdependent. 

Table III. Effect of Gamma Radiation on Properties of Ethylene—Butene Copolymer...

Bond strength data for four multilayered materials is shown in Table V. In each case the data is for the bond between the food-contacting layer and its adjacent layer. In Pouch 1, it is the bond between ethylene-butene copolymer and aluminum foil in Pouch 2 between ethylene-butene copolymer—polyisobutylene blend and aluminum foil in Pouch 3 between ethylene-butene copolymer and polyiminocaproyl and in Pouch 4 between ethylene-butene copolymer and poly(ethylene terephthalate). Bond strength increased in the four multilayered materials after the irradiation treatment. 

All values are with respect to that of reference polymer hydrogenated polybutadiene (HPB97), model ethylene-butene copolymer, x wt% butene. 

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. 

Figure 4 Plot of degree of crystallinity (XDSC) from DSC against crystallinity (Xp) determined by density measurements. (A), hydrogenated polybutadienes ( ), ethylene 1-butene copolymers ( ), ethylene 1-octene copolymers. Reprinted with permission from Ref. [72]. Copyright 1984 American Chemical Society. 

Its actual molecular weight, as obtained from gel permeation chromatography, is My, = 1263 M = 1136. (29) Its melting teir ier-ature, under the conditions of the NMR measurements, was 108.8°C as determined by differential calorimetry. The low density (branched) polyethylenes studied here were commercial varieties whose molecular weights, distribution and side group concentrations have been reported. (30) The ethylene-butene-1 copolymers were a gift from the Exxon Chemical Corporation. 

Figure 6. Plot of linewidth, against temperature at 67.9 MHz for ethylene-butene-1 random copolymers. Co-unit contents d), 10 ( ), 7 (0), 21 (O), 26.

The homopolymers of low levels of crystallinity, as well as the ethylene-butene-1 copolymers, which are either completely cimorphous, or slightly crystalline at the temperatures of measurement, also display frequency-dependent linewidths. 

Corradini, P., and P. Ganis X-Ray Study of the Structure of the Alternated Copolymer Ethylene-cis-butene-2. Makromolekulare Chem. 62, 97 (1963). 

Four olefins are used in industry to manufacture ethylene copolymers 1-butene, 1-hexene, 4-methyl-1-pentene. and 1-octene. Copolymers containing 1-butene account for approximately 40% of all LLDPE resins manufactured worldwide, 1-hexene copolymers for 35%, 1-octene copolymers for about 20%, and 4-mcthyl-l-pcntcnc copolymers for the rest. The type of o-olcliit exerts a significant influence oil tlie copolymer properties. 

Copolymers may also be produced with a catalyst containing both chromium oxide and nickel oxide supported on silica-alumina. It is well-known that nickel oxide—silica—alumina by itself makes predominantly butenes from ethylene. In the mixed catalyst, butenes that are formed on nickel oxide copolymerize with ethylene on the chromium oxide to form ethylene-butene copolymers. The fact that infrared shows only ethyl branching in the polymer indicates that the initial product... 

Fig. 16 ESC (50% failure) of various ethylene-butene copolymers for different amounts of C2H5 branches and different molecular weights (inherent viscosities)...

Two compounds of this type were placed at our disposal isotactic polypropylene and an alternating erythro-iso-copolymer of butene-2 and ethylene. Looking to the extended chemical formula of the latter (Figure 13), it is indeed immediately evident that this copolymer can be considered as an equivalent to a HH polypropylene. The XPS analysis of the valence band spectrum of this compound reveals that its electronic structure, reflected through the C-C (C2s) molecular orbitals is entirely different from that of polypropylene (Figure 14). 

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