Properties of amorphous and crystallizable hydrocarbon polymers. III. Studies of the hydrogenation of polybutadiene

Rachapudy, H.; Smith, Gregory G.; Raju, V. Ramachandra; Graessley, William W.

doi:10.1002/pol.1979.180170706

Cited by 162 publications

(122 citation statements)

References 7 publications

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“…A partially deuterated poly(ethylene-block-head-to-head propylene) copolymer (PE-PP) and a fully hydrogenous polyisobutylene (PIB) homopolymer were synthesized and characterized by methods described in refs [43][44][45]. The chemical structures of the polymers (ignoring the deuterium labels) are shown in Figure 1.…”

Section: Methodsmentioning

confidence: 99%

Thermodynamics and Phase Behavior of Block Copolymer/Homopolymer Blends with Attractive and Repulsive Interactions

et al. 2002

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Small-angle neutron scattering (SANS) experiments were conducted on a 25 vol % blend of a poly(ethylene-block-head-to-head propylene) copolymer (PE-PP) in polyisobutylene (PIB). PE/PIB and PE/PP chains are incompatible (the Flory-Huggins interaction parameter > 0), while PIB and PP are compatible ( < 0) at low temperatures and incompatible ( > 0) at high temperatures. These interactions lead to an order-disorder transition at 150 ( 5°C and macrophase separation at 251 ( 5°C. The nature of the concentration fluctuations in the homogeneous state (155°C < T < 246°C) was studied by comparing the experimentally determined SANS profiles with theoretical calculations based on the multicomponent random phase approximation (RPA). Order formation at low temperatures is driven by two parameters:PE/PIB and lPP (the statistical segment length of the PP block). The other temperature-dependent parameters drive the system away from the ordering transition. At high temperatures, the RPA predicts microphase separation, while experimental data (neutron and light scattering) indicate macrophase separation. This discrepancy is mainly due to the inability of the RPA to correctly account for the large length scale concentration fluctuations.

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Section: Methodsmentioning

confidence: 99%

Thermodynamics and Phase Behavior of Block Copolymer/Homopolymer Blends with Attractive and Repulsive Interactions

et al. 2002

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“…A triethyl aluminium/cobalt 2-ethyl hexanoate complex was used as homogeneous hydrogenation catalyst [10]. This complex was prepared by adding dropwise the transition metal salt (0.2 M in toluene) to the metal alkyl (1 M in toluene) under nitrogen.…”

Section: Hydrogenationmentioning

confidence: 99%

“…This problem has been alleviated by the selective hydrogenation of the PBD block with formation of a polyolefin block known for resistance to thermo-and photo-oxidation [8]. For this reason, hydrogenation of polydiene and styrene-diene copolymers has been extensively studied [8][9][10][11][12][13], and particularly discussed in two recent reviews by Schulz [11] and McManus [13]. Only a few papers have focused on the hydrogenation of alkylmethacrylatediene copolymers [14][15][16].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of hydrogenated poly[alkylmethacrylate(-b-styrene)-b-butadiene-b-(styrene-b-) alkylmethacrylate] triblock and pentablock copolymers

Yu¹,

Yu²,

Dubois³

et al. 1997

Polymer

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Triblock and pentablock copolymers of the X(Y)B(Y)X type have been synthesized by the sequential living anionic polymerization of butadiene (B), styrene (Y) and alkylmethacrylate (X), respectively. The diadduct of tBuLi onto m-diisopropenylbenzene (m-DIB) has been used as a difunctional initiator. Methylmethacrylate (MMA), t-butylmethacrylate (tBMA) and isobornylmethacrylate (IBMA) have been used as precursors of the outerblocks X. The polybutadiene (PBD) midblock that contains ca 42-45% 1,2-units has been selectively hydrogenated into a saturated poly(ethylene-co-1-butene) (PEB) block. The homogeneous hydrogenation catalysis has no deleterious effect on the copolymer integrity. These completely soluble thermoplastic elastomers have been characterized by FT i.r., n.m.r., d.s.c. and d.m.a. The PEB midblock has a low T g (-50°C) and a small propensity to crystallize. The effect of hydrogenation on the morphology and mechanical properties depends on the outer block. Upon hydrogenation of the PBD midblock in polymethylmethacrylate (PMMA) and polyisobornylmethacrylate (PIBMA) containing triblock copolymers, the ultimate tensile strength is increased (except for a hard block content > 50%) due to a sharper phase separation, whereas the elongation at break is decreased. The extent of phase separation is reduced in polyt-butylmethacrylate(PtBMA) containing triblock copolymers upon hydrogenation and the ultimate tensile strength is slightly decreased. Stereocomplexation of the syndiotactic PMMA outerblocks is observed to occur upon blending with isotactic PMMA

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“…The choice of this system was motivated by several factors. First, the polymers can be synthesized by a straightforward anionic polymerization/hydrogenation procedure 105,106 and are stable indefinitely under ambient conditions. In addition, the semicrystalline nature of PE allows the BmE morphology to be captured in a solid material.…”

Section: Introductionmentioning

confidence: 99%

Nanocasting nanoporous inorganic and organic materials from polymeric bicontinuous microemulsion templates

Jones

Lodge

2012

Polym J

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Ternary blends of two homopolymers and a diblock copolymer can self-assemble into interpenetrating, three-dimensionally continuous networks with a characteristic length scale of B100 nm. In this review, we summarize our recent work demonstrating that these equilibrium fluid phases, known as polymeric bicontinuous microemulsions (BlE), can be designed as versatile precursors to nanoporous materials having pores with uniform sizes of B100 nm. As a model system, nanoporous polyethylene (PE) is derived from BlEs composed entirely of polyolefins. This monolithic material is then used as a template in the synthesis of other nanoporous materials for which structural control at the nm scale has traditionally been difficult to achieve. These materials, which include a high-temperature ceramic, polymeric thermosets and a conducting polymer, are produced by a simple nanocasting process, providing an inverse replica of the PE template. The PE is further used as a template for the production of hierarchically structured inorganic and polymeric materials by infiltration of mesostructured compounds into its pore network. The work described herein represents an unprecedented suite of nanoporous materials with well-defined pore structures prepared from a single PE template. They are anticipated to have potential application in diverse technological areas, including catalysis, separations and electronic devices.

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Properties of amorphous and crystallizable hydrocarbon polymers. III. Studies of the hydrogenation of polybutadiene

Cited by 162 publications

References 7 publications

Thermodynamics and Phase Behavior of Block Copolymer/Homopolymer Blends with Attractive and Repulsive Interactions

Thermodynamics and Phase Behavior of Block Copolymer/Homopolymer Blends with Attractive and Repulsive Interactions

Synthesis and characterization of hydrogenated poly[alkylmethacrylate(-b-styrene)-b-butadiene-b-(styrene-b-) alkylmethacrylate] triblock and pentablock copolymers

Nanocasting nanoporous inorganic and organic materials from polymeric bicontinuous microemulsion templates

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