Influence of Segmental Swelling Ratio of a Symmetric Block Copolymer on the Morphology of Melt-Mixed Immiscible Polymer Blends

Kim, Jong Ryang; Jamieson, A. M.; Hudson, Steven D.; Manas‐Zloczower, Ica; Ishida, Hatsuo

doi:10.1021/ma990177h

Cited by 20 publications

(10 citation statements)

References 16 publications

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“…Other studies have concluded27, 29, 30 that copolymers with substantially shorter blocks can show high efficiency. The rule for the prediction of compatibilization efficiency suggested by Kim et al31 is not applicable to systems with block lengths substantially shorter than the lengths of the compatibilized chains. Recently, the compatibilization efficiency of a set of model block copolymers, with different numbers of blocks and with styrene blocks of different lengths, in blends of PS with various polyolefins has been studied 32–39.…”

Section: Introductionmentioning

confidence: 95%

Effect of the molecular structure of ethene–propene and styrene–butadiene copolymers on their compatibilization efficiency in low‐density polyethylene/polystyrene blends

Starý

Fortelný

Kruliš

et al. 2007

J of Applied Polymer Sci

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The effect of the molecular structure of styrene-butadiene (SB) block copolymers and ethene-propene (EPM) random copolymers on the morphology and tensile impact strength of low-density polyethylene (LDPE)/polystyrene (PS) (75/25) blends has been studied. The molecular characteristics of SB block copolymers markedly influence their distribution in LDPE/PS blends. In all cases, an SB copolymer is present not only at the interface but also in the bulk phases; this depends on its molecular structure. In blends compatibilized with diblock copolymers, compartmentalized PS particles can also be observed. The highest toughness values have been achieved for blends compatibilized with triblock SB copolymers. A study of the compatibilization efficiency of SB copolymers with the same number of blocks has shown that copolymers with shorter PS blocks are more efficient. A comparison of the obtained results with previous results indicates that the compatibilization efficiency of a copolymer strongly depends both on the blend composition and on the properties of the components. The compatibilization efficiency of an EPM/SB mixture is markedly affected by the rheological properties of the copolymers. The addition of an EPM/ SB mixture containing EPM with a higher viscosity leads to a higher improvement or at least the same improvement in the tensile impact strength of a compatibilized blend as the same amount of neat SB.

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Section: Introductionmentioning

confidence: 95%

Effect of the molecular structure of ethene–propene and styrene–butadiene copolymers on their compatibilization efficiency in low‐density polyethylene/polystyrene blends

Starý

Fortelný

Kruliš

et al. 2007

J of Applied Polymer Sci

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“…Kim et al20 suggested, using the ratio of the swelling power at the interface of the block copolymer segment outside the droplet to that inside the droplet, S r , for prediction of the compatibilization efficiency. Using the results for the poly(cyclohexyl methacrylate)/poly(styrene‐ ran ‐acrylonitrile) blend compatibilized with poly(styrene‐ block ‐methyl methacrylate) diblock copolymer, they concluded that block copolymers are inefficient emulsifiers if S r < 0.4 or S r > 2.5.…”

Section: Introductionmentioning

confidence: 99%

Transoral power‐assisted marsupialization of vallecular cysts under local anesthesia

et al. 2012

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The effect of styrene–butadiene block copolymers (SB) with varying number of blocks and length of styrene blocks on the morphology, rheology, and impact strength of 4/1 polystyrene/low‐density polyethylene (PS/LDPE) blends was studied. The scanning and transmission electron microscopy and X‐ray scattering were used for determination of the size of LDPE particles and the localization and structure of SB copolymers in blends. It is shown that the dependence of the LDPE particle size on the amount of added SB and localization of SB copolymers in blends is predominantly controlled by the length of their styrene blocks. It follows from thermodynamic considerations that the reason is the difference in composition asymmetry between SB with short and long styrene blocks. Coalescence of particles of SB having short styrene blocks at the surface of LDPE droplets and movement of SB with long styrene blocks to the PS–LDPE interface were observed during annealing of PS/LDPE/SB blends. Pronounced migration of SB copolymer during annealing shows that their localizations in blends in steady state on long steady mixing and at thermodynamic equilibrium are different. The values of tensile impact strength of PS/LDPE/SB blends correlate well with the size of LDPE particles and the amount of SB at the interface. Viscosity of PS/LDPE/SB depends on molecular structure of SB copolymers by a manner different from that of tensile impact strength. The results of this study and literature data lead to the conclusion that the compatibilization efficiency of SB copolymers for a certain polystyrene‐polyolefin pair is a function of not only molecular parameters of SB but also of the polystyrene/polyolefin ratio, the amount of SB in a blend, and mixing and processing conditions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2803–2816, 2006

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“…It cannot be a priori excluded that the PS/PB ratio is one of the parameters controlling the effect of SB on the structure and properties of PS/PE/SB blends. On the other hand, it seems from thermodynamic analysis that the distribution of a block copolymer between the interface and bulk phases is determined by the ratios of the block length and the related blend components and their interaction parameters 22. The direct effect of the ratio of plastic PS and rubbery PB in SB copolymers on the impact strength of PS/PE/SB blends should be apparently stronger than that on their morphology and flow properties.…”

Section: Resultsmentioning

confidence: 99%

Effect of molecular structure of styrene–butadiene block copolymers on morphology, rheological properties, and impact strength of polystyrene/polyethylene blends

Fortelný

Mikešová

Hromádková

et al. 2003

J of Applied Polymer Sci

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ABSTRACT:The effect of molecular structure of six model styrene-butadiene (SB) block copolymers with various number of blocks and two lengths of styrene blocks on morphology, rheological properties, and impact strength of polystyrene (PS)/high-density polyethylene (PE) blends was studied. It was found that location of SB copolymers in the blends is determined by the length of styrene blocks. The length of styrene blocks has similar effects on impact strength and linear viscoelastic properties of the blends. On the other hand, the correlation was not found between the effects of a number of blocks on impact strength and linear viscoelastic properties of the blends.

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Influence of Segmental Swelling Ratio of a Symmetric Block Copolymer on the Morphology of Melt-Mixed Immiscible Polymer Blends

Cited by 20 publications

References 16 publications

Effect of the molecular structure of ethene–propene and styrene–butadiene copolymers on their compatibilization efficiency in low‐density polyethylene/polystyrene blends

Effect of the molecular structure of ethene–propene and styrene–butadiene copolymers on their compatibilization efficiency in low‐density polyethylene/polystyrene blends

Transoral power‐assisted marsupialization of vallecular cysts under local anesthesia

Effect of molecular structure of styrene–butadiene block copolymers on morphology, rheological properties, and impact strength of polystyrene/polyethylene blends

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