Conformation of PS-PMMA Diblock Copolymer in Toluene by Small Angle Neutron Scattering

1977 ◽  
Vol 10 (1) ◽  
pp. 44-51 ◽  
Author(s):  
C. C. Han ◽  
B. Mozer
Keyword(s):  
Neutron Scattering ◽  
Diblock Copolymer ◽  
Small Angle ◽  
Small Angle Neutron Scattering

scholarly journals Spin-echo small-angle neutron scattering (SESANS) studies of diblock copolymer nanoparticles

Soft Matter ◽  
2019 ◽  
Vol 15 (1) ◽  
pp. 17-21
Author(s):  
Gregory N. Smith ◽  
Victoria J. Cunningham ◽  
Sarah L. Canning ◽  
Matthew J. Derry ◽  
J. F. K. Cooper ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Diblock Copolymer ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Spin Echo ◽  
Real Space ◽  
Polymer Nanoparticles ◽  
High Contrast ◽  
Concentrated Dispersions

Concentrated dispersions of polymer nanoparticles with high contrast can be studied using SESANS in real space.

Inhomogeneous dynamic nuclear polarization of protons in a lamella-forming diblock copolymer investigated by a small-angle neutron scattering method

2011 ◽  
Vol 44 (3) ◽  
pp. 503-513 ◽  
Author(s):  
Yohei Noda ◽  
Takayuki Kumada ◽  
Takeji Hashimoto ◽  
Satoshi Koizumi
Keyword(s):  
Neutron Scattering ◽  
Diblock Copolymer ◽  
Dynamic Nuclear Polarization ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Nuclear Polarization ◽  
Spin Diffusion ◽  
Second Order ◽  
Third Order ◽  
Proton Polarization

By combining two methods of selective doping of paramagnetic species into a microdomain and small-angle neutron scattering (SANS), thespatially inhomogeneous proton polarizationcreated by dynamic nuclear polarization (DNP) has been precisely evaluated. A lamella-forming diblock copolymer composed of polystyrene (PS) and polyisoprene (PI) block chains (PS-b-PI) was employed, the SANS profile of which clearly shows scattering peaks up to the third order due to interlamellar interference. As a source of electron spin for DNP, 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) was doped into one or other of the microdomains; samples with PS or PI microdomains selectively doped with TEMPO are designated PS.-b-PI and PS-b-PI., respectively. The SANS intensity at the first- and third-order peaks is well reproduced by assuming that the proton polarization is homogeneous throughout the sample, but that at the second-order peak cannot be explained by this assumption. This anomaly regarding the second-order peak was successfully explained by a model postulating that proton polarization in a doped microdomain decreases with increasing distance from the interface with a neighbouring doped microdomain. The decrease in proton polarization at the centre of a doped microdomain was estimated to be 0.07 (2) for PS-b-PI.and 0.05 (1) for PS.-b-PI, relative to constant proton polarization in a doped microdomain. The inhomogeneous proton polarization results from two competing dynamic processes,i.e.spin diffusion from doped to undoped microdomains, and spin lattice relaxation occurring on the pathway of proton spin diffusion.

Morphology determination of defect-rich diblock copolymer films with time-of-flight grazing-incidence small-angle neutron scattering

2014 ◽  
Vol 47 (4) ◽  
pp. 1228-1237 ◽  
Author(s):  
Peter Müller-Buschbaum ◽  
Gunar Kaune ◽  
Martin Haese-Seiller ◽  
Jean-Francois Moulin
Keyword(s):  
Neutron Scattering ◽  
Diblock Copolymer ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Microphase Separation ◽  
Time Of Flight ◽  
Surface Region ◽  
Grazing Incidence ◽  
Near Surface ◽  
Oriented Parallel

The complex nanomorphology of a defect-rich deuterated poly(styrene-block-methyl methacrylate), P(S-b-MMAd), diblock copolymer film is determined with a combination of grazing-incidence small-angle neutron scattering (GISANS) and time-of-flight (TOF) mode. TOF-GISANS enables the simultaneous performance of several GISANS measurements that differ in wavelength. The resulting set of GISANS data covers different ranges of the scattering vector and has different scattering depths. Thus surface-sensitive and bulk-sensitive measurements can be performed simultaneously. The P(S-b-MMAd) film exhibits a lamellar microphase separation structure, which because of the defects is arranged into small, randomly oriented grains, composed of four–five lamellar repetitions. In the near-surface region, the lamellar structure is oriented parallel to the substrate, which explains the smooth surface found with atomic force microscopy.

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