Isoprene/styrene block copolymer

Styrene isoprene block copolymers Styrene butadiene block copolymers Styrene butadiene random copolymers Polyisobutylene Polysiloxanes... 

Cakmak M. and Wang M.D., Structure development in the tubular blown film of PP/EPDM thermoplastic elastomer, Antec 89, 47th Annual Tech. Conference of SPE, New York, May 1, 1989, 1756. Hashimoto T., Todo A., Itoi H., and Kawai H. Domain boundary structure of styrene-isoprene block copolymer films cast from solution. 2. Quantitative estimation of the interfacial thickness of lamellar microphase systems. Macromolecules, 10, 377, 1977. 

Fig. 49. Zimm plot for a styrene/isoprene block copolymer in methyl isobutyl ketone153)...

The effect of blending LDPE with EVA or a styrene-isoprene block copolymer was investigated (178). The properties (thermal expansion coefficient. Young s modulus, thermal conductivity) of the foamed blends usually lie between the limits of the foamed constituents, although the relationship between property and blend content is not always linear. The reasons must he in the microstructure most polymer pairs are immiscible, but some such as PS/polyphenylene oxide (PPO) are miscible. Eor the immiscible blends, the majority phase tends to be continuous, but the form of the minor phase can vary. Blends of EVA and metallocene catalysed ethylene-octene copolymer have different morphologies depending on the EVA content (5). With 25% EVA, the EVA phase appears as fine spherical inclusions in the LDPE matrix. The results of these experiments on polymer films will apply to foams made from the same polymers. 

Ober and coworkers117 have grafted siloxanes onto a styrene-isoprene block copolymer via hydrosilylation of the pendant vinyl groups of the diene block with pentamethyldis-iloxane (30) (equation 12). 

Styrene-butadiene block copolymer Styrene-isoprene block copolymer Styrene-ethylene block copolymer Styrene-butylene block copolymer... 

Hashimoto T, Nagatoshi K (1974) Domain-boundary structure of styrene-isoprene block copolymer films cast from toluene solutions. Macromolecules 7 364-373... 

Adams JL, Graessley WM et al (1994) Rheology and the microphase separation transition in styrene-isoprene block copolymers. Macromolecules 27 6026-6032... 

All this does not prevent attempts to utilize all established pieces of knowledge for practical purposes. For example, styrene-isoprene block copolymers have been successfully synthesized in this rather complicated medium [158]. 

The alkyl-lithium initiated, living anionic polymerization of elastomers was described in 1928 by Ziegler. To polymerize styrene-isoprene block copolymers Szwarc et al., [1956] used sodium naphthalene as an anion-radical di-initiator, while Shell used an organolithium initiator. The polymerization mechanism was described by By water [1965]. 

PPE, PP and PPS with hydrogenated styrene-isoprene block copolymers heat, impact and solvent resistance Maruyama Mizuno, 1990... 

Figure 4.4. Interphase thickness in styrene-isoprene block copolymers vs. total molecular weight. Points are experimental [Hashimoto et al., 1980 Richars and Thomason, 1983], the hne was computed from Eq 4.13 using Al = 1.9 nm and X = 1000 Xae o = 0-6.

Figure 8.12. The Debye-Bueche plots for ternary blends of polystyrene, polyisoprene, and styrene-isoprene block copolymers [Moritani et at, 1970],...

We will focus in this paper on the rheological properties, at room temperature, of styrene-isoprene block copolymers, particularly Triblock [SISj-Diblock [SI] copolymer blends. We will describe the effect of the molecular parameters of the copolymers on the rheological behavior, and wiU propose, on the basis of molecular dynamics models derived from the reptation concept and the analysis of the dynamic behavior of the blend [SIS-SI], a model which allows calculation of the variation of the complex shear modulus as a function of frequency. Different types of macromolecules have been designed from calculations using this molecular model in order to improve the processing and end-user properties of the full formulations (HMPSAs). 

Electron microscopy measurements on a very thin film of a styrene-isoprene block copolymer of 15,000 and 75,000 bloek molecular weights indicated that the polystyrene blocks form a spherical morphology with domains of 260 A diameter (Meier, 1969). Calculate the predicted domain size for this morphology (K = 0.670 A and assume a = 1.2). 

Toporowski, R, and Roovers, J. E. L., Glass transition temperature of low molecular weight Styrene-isoprene block copolymers,/. Polym. Sci. Polym. Chem. Ed., 14,2233-2242(1976). 

In the second system, a commercial styrene isoprene block copolymer was formulated according to ... 

This method was applied to styrene-isoprene block copolymers of AB and ABA types having relatively narrow molecular mass distributions [11]. Universal calibration curves for PS, polyisoprenes, and their block copolymers fell on the same line. Conversion to log M v. Fr was accomplished by obtaining intrinsic viscosities of these copolymers, which were closely related to those of the corresponding homopolymers of equal molecular mass by... 

PP was blended with hydrogenated styrene-butadiene or styrene-isoprene block copolymer, 6-8 wt%. The alloys were used for the manufacturing of materials with good transparency and impact strength... 

Semicrystalline ethylene-propylene copolymer, EP, was blended with amorphous EP and inorganic filler. The blends had good processability, mechanical properties, and impact strength. In the Mitsubishi patent, crystalline EP was blended with styrene-isoprene block copolymer, 5-30 wt% SIS, and polystyrene, 3-5 wt% PS, to give good paintability... 

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