Effect of the isothermal crystallization method on amorphous block copolymers of aromatic polyamides and their packing behavior in two-dimensional films for screening of potential crystallization ability

Abstract Anionically prepared block copolymers of butadiene and styrene exhibit solution properties which result from a two dimensional ordering of the polymer molecules. The most notable of these properties is the iridescent colors of toluene solutions which are dependent on concentration and abruptly change on mechanical deformation. Electron micrographs of the surface of cast films indicate that the ordered structure is retained to some degree in the solid state.

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Two-Dimensional Heterospectral Correlation Analysis of Wide-Angle X-ray Scattering and Infrared Spectroscopy for Specific Chemical Interactions in Weakly Interacting Block Copolymers

The Journal of Physical Chemistry B ◽

10.1021/jp0638282 ◽

2006 ◽

Vol 110 (46) ◽

pp. 23123-23129 ◽

Cited By ~ 29

Author(s):

Hye Jeong Kim ◽

Seung Bin Kim ◽

Jin Kon Kim ◽

Young Mee Jung

Keyword(s):

Infrared Spectroscopy ◽

Block Copolymers ◽

Correlation Analysis ◽

Wide Angle ◽

Two Dimensional ◽

Chemical Interactions ◽

Specific Chemical ◽

X Ray ◽

X Ray Scattering ◽

Weakly Interacting

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Two-dimensional chromatography of complex polymers. 3. Full analysis of polystyrene-poly(methyl methacrylate) diblock copolymers

e-Polymers ◽

10.1515/epoly.2002.2.1.69 ◽

2002 ◽

Vol 2 (1) ◽

Cited By ~ 3

Author(s):

Harald Pasch ◽

Kibret Mequanint ◽

Adrian Jörg

Keyword(s):

Block Copolymers ◽

Methyl Methacrylate ◽

Diblock Copolymers ◽

Size Exclusion ◽

Molecular Heterogeneity ◽

Two Dimensional ◽

Poly Methyl Methacrylate ◽

Mass Distributions ◽

Exclusion Chromatography ◽

Complex Polymers

AbstractPoly(styrene-block-methyl methacrylate)s were fully analyzed by liquid chromatography at the critical point of adsorption (LC-CC) and two-dimensional chromatography. Operating at chromatographic conditions corresponding to the critical points of the homopolymers polystyrene and poly(methyl methacrylate), the block lengths distributions for the different blocks of the block copolymers were determined quantitatively. Information on the amounts and molar mass distributions of homopolymers and coupling products that were identified in the samples as by-products was obtained by on-line coupled 2D chromatography. It was shown that a complete picture of the molecular heterogeneity of block copolymers can be obtained only when information from different chromatographic experiments is combined. Size exclusion chromatography alone is inappropriate for evaluating the molecular heterogeneity of such samples.

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Crystallization Time Dependence of Nanohybrid Shish-Kebab Structure in HDPE/PA66 Nanofibers Composites via Solution Crystallization

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.110-116.3786 ◽

2011 ◽

Vol 110-116 ◽

pp. 3786-3790

Author(s):

Wen Juan Han ◽

Guo Qiang Zheng ◽

Yan Yan Liang ◽

Chun Tai Liu ◽

Chang Yu Shen

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Time Dependence ◽

Isothermal Crystallization ◽

Three Dimensional ◽

Crystallization Time ◽

Two Dimensional ◽

Solution Crystallization ◽

Dimensional Growth ◽

Scanning Electron

In this study, PA66 nanofibers were successfully solution electrospun. The crystalline morphological features of HDPE solution induced by nanofibers were investigated by scanning electron microscopy (SEM). Nanohybrid shish-kebab (NHSK) can be formed in HDPE solution via isothermal crystallization, in which PA66 nanofibers serve as shish and HDPE lamellae act as kebabs surrounding the nanofibers periodically. Additionally, crystallization time has significant effect on the structure of HDPE kebab in NHSK, i.e., as crystallization time increases, the size of the kebab increases and the crystals decorated on PA66 nanofibers exhibit a three-dimensional growth (i.e., aggregate of crystallites) rather than a two-dimensional one (i.e., disc-like lamellae normal to the axis of nanofiber).

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Scattering patterns and stress–strain relations on phase-separated ABA block copolymers under uniaxial elongating simulations

Soft Matter ◽

10.1039/c8sm02363h ◽

2019 ◽

Vol 15 (5) ◽

pp. 926-936 ◽

Cited By ~ 3

Author(s):

Katsumi Hagita ◽

Keizo Akutagawa ◽

Tetsuo Tominaga ◽

Hiroshi Jinnai

Keyword(s):

Molecular Dynamics ◽

Block Copolymers ◽

Molecular Dynamics Simulations ◽

Coarse Grained ◽

Two Dimensional ◽

Stress Strain ◽

Uniaxial Stretching ◽

Dynamics Simulations ◽

Coarse Grained Molecular Dynamics

To develop molecularly based interpretations of the two-dimensional scattering patterns (2DSPs) of phase-separated block copolymers (BCPs), we performed coarse-grained molecular dynamics simulations of ABA tri-BCPs under uniaxial stretching for block-fractions where the A-segment (glassy domain) is smaller than the B-segment (rubbery domain), and estimated the behaviour of their 2DSPs.

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