Analysis of Surface Segregation in Blends of Acrylate Copolymer with Fluoro-Copolymer.

Sn has been used extensively as an n-type dopant in GaAs grown by molecular-beam epitaxy (MBE). The surface accumulation of Sn during the growth of Sn-doped GaAs has been observed by several investigators. It is still not clear whether the accumulation of Sn is a kinetically hindered process, as proposed first by Wood and Joyce, or surface segregation due to thermodynamic factors. The proposed donor-incorporation mechanisms were based on experimental results from such techniques as secondary ion mass spectrometry, Auger electron spectroscopy, and C-V measurements. In the present study, electron microscopy was used in combination with cross-section specimen preparation. The information on the morphology and microstructure of the surface accumulation can be obtained in a fine scale and may confirm several suggestions from indirect experimental evidence in the previous studies.

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A New Numerical Model for Electron-Probe Analysis at High Depth Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016491x ◽

1996 ◽

Vol 54 ◽

pp. 490-491

Author(s):

P.-F. Staub ◽

C. Bonnelle ◽

F. Vergand ◽

P. Jonnard

Keyword(s):

Electron Probe ◽

Surface Segregation ◽

Depth Distribution ◽

Computing Time ◽

Depth Resolution ◽

Physical Parameters ◽

Electron Probe Analysis ◽

Interface Phases ◽

Excitation Conditions ◽

High Depth

Characterizing dimensionally and chemically nanometric structures such as surface segregation or interface phases can be performed efficiently using electron probe (EP) techniques at very low excitation conditions, i.e. using small incident energies (0.5<E0<5 keV) and low incident overvoltages (1<U0<1.7). In such extreme conditions, classical analytical EP models are generally pushed to their validity limits in terms of accuracy and physical consistency, and Monte-Carlo simulations are not convenient solutions as routine tools, because of their cost in computing time. In this context, we have developed an intermediate procedure, called IntriX, in which the ionization depth distributions Φ(ρz) are numerically reconstructed by integration of basic macroscopic physical parameters describing the electron beam/matter interaction, all of them being available under pre-established analytical forms. IntriX’s procedure consists in dividing the ionization depth distribution into three separate contributions:

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Surface segregation in model symmetric polyolefin diblock copolymer melts

Journal de Physique II ◽

10.1051/jp2:1994258 ◽

1994 ◽

Vol 4 (12) ◽

pp. 2231-2248 ◽

Cited By ~ 6

Author(s):

Mohan Sikka ◽

Navjot Singh ◽

Frank S. Bates ◽

Alamgir Karim ◽

Sushil Satija ◽

...

Keyword(s):

Diblock Copolymer ◽

Surface Segregation ◽

Copolymer Melts

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XPS study of the chemisorption induced surface segregation in LaNi5 and ThNi5

Journal de Physique ◽

10.1051/jphys:019810042070102500 ◽

1981 ◽

Vol 42 (7) ◽

pp. 1025-1028 ◽

Cited By ~ 20

Author(s):

L. Schlapbach ◽

C.R. Brundle

Keyword(s):

Surface Segregation ◽

Xps Study

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Is it a Right Assumption That B and Ge are Distributed Randomly After Growing a Strained HBT-Structure?

MRS Proceedings ◽

10.1557/proc-716-b4.7 ◽

2002 ◽

Vol 716 ◽

Author(s):

Victor I. Kol'dyaev

Keyword(s):

Surface Segregation ◽

Initial Conditions ◽

Initial Condition ◽

Basic Assumptions ◽

Transient Diffusion ◽

Segregation Process ◽

Main Observation

AbstractIt is accepted that surface Ge atoms are considered to be responsible for the surface B segregation process. A set of original experiments is carried out. A main observation from the B and Ge profiles grown at different conditions shows that at certain conditions B is taking initiative and determine the Ge surface segregation process. basic assumptions are suggested to self-consistently explain these original experimental features and what is observed in the literature. These results have a strong implication for modeling the B diffusion in Si1-xGex where the initial conditions should be formulated accounting for the correlation in B and Ge distribution. A new assumption for the initial condition to be “all B atoms are captured by Ge” is regarded as a right one implicating that there is no any transient diffusion representing the B capturing kinetics.

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STUDYING REACTIVITY RATIOS AND PHYSICAL PROPERTIES OF METHACRYLIC ACID - ETHYL ACRYLATE COPOLYMER

Vietnam Journal of Science and Technology ◽

10.15625/0866-708x/53/2/4002 ◽

2015 ◽

Vol 53 (2) ◽

Author(s):

Tran Vu Thang ◽

Pham Thi Thu Ha ◽

Nguyen Van Khoi ◽

Nguyen Van Manh ◽

Pham Thi Thu Trang

Keyword(s):

Physical Properties ◽

Methacrylic Acid ◽

Ethyl Acrylate ◽

Reactivity Ratios ◽

Acrylate Copolymer

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The Appearance of Pitting on Thermally Grown Aluminum Oxide caused by Surface Segregation of Fe Impurities from the Bulk

Practical Metallography ◽

10.3139/147.110427 ◽

2016 ◽

Vol 53 (11) ◽

pp. 681-695

Author(s):

D. E. Diaz-Droguett ◽

P. Núñez ◽

A. L. Cabrera

Keyword(s):

Aluminum Oxide ◽

Surface Segregation ◽

Fe Impurities ◽

Thermally Grown

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Tracking Hydroplasticization by DSC: Movement of Water Domains Bound to Poly(Meth)Acrylates during Latex Film Formation

Polymers ◽

10.3390/polym12112500 ◽

2020 ◽

Vol 12 (11) ◽

pp. 2500

Author(s):

Sebastian M. Dron ◽

Maria Paulis

Keyword(s):

Itaconic Acid ◽

Water Resistance ◽

Film Formation ◽

Latex Film ◽

Water Molecules ◽

Acrylate Copolymer ◽

Volatile Organic ◽

Minimum Film Formation Temperature ◽

Latex Film Formation ◽

Formation Step

The film formation step of latexes constitutes one of the challenges of these environmentally friendly waterborne polymers, as the high glass transition (TG) polymers needed to produce hard films to be used as coatings will not produce coherent films at low temperature. This issue has been dealt by the use of temporary plasticizers added with the objective to reduce the TG of the polymers during film formation, while being released to the atmosphere afterwards. The main problem of these temporary plasticizers is their volatile organic nature, which is not recommended for the environment. Therefore, different strategies have been proposed to overcome their massive use. One of them is the use of hydroplasticization, as water, abundant in latexes, can effectively act as plasticizer for certain types of polymers. In this work, the effect of three different grafted hydroplasticizers has been checked in a (meth)acrylate copolymer, concluding that itaconic acid showed the best performance as seen by its low minimum film-formation temperature, just slightly modified water resistance and better mechanical properties of the films containing itaconic acid. Furthermore, film formation monitoring has been carried out by Differential Scanning Calorimety (DSC), showing that itaconic acid is able to retain more strongly the water molecules during the water losing process, improving its hydroplasticization capacity.

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