Synthesis, morphology and properties of poly(dimethylsiloxane)/poly(n-butyl acrylate) mixed soft block-based copolymers: A new class of thermoplastic elastomer

Polymer ◽  
2012 ◽  
Vol 53 (7) ◽  
pp. 1453-1464 ◽  
Author(s):  
Ravikumar Muppalla ◽  
Suresh K. Jewrajka
Keyword(s):  
Butyl Acrylate ◽  
Thermoplastic Elastomer ◽  
New Class ◽  
Block Based

Controlled copolymerization of n-butyl acrylate with semifluorinated acrylates by RAFT polymerization

2015 ◽  
Vol 6 (3) ◽  
pp. 448-458 ◽  
Author(s):  
Senbin Chen ◽  
Wolfgang H. Binder
Keyword(s):  
Butyl Acrylate ◽  
Raft Polymerization ◽  
Reactivity Ratios ◽  
New Class ◽  
Tof Ms

A new class of well-controlled semifluorinated copolymers were successfully synthesized via RAFT polymerization. We found that ESI-TOF MS was particularly useful for readily analysing our semifluorinated copolymers. The reactivity ratios of each pair of co-monomers are close to one.

scholarly journals Extending multimedia languages to support multimodal-multiuser interactions

2019 ◽  
Author(s):  
Álan L. V. Guedes ◽  
Simone D. J. Barbosa
Keyword(s):  
User Study ◽  
User Acceptance ◽  
Seamless Integration ◽  
Multiple Modalities ◽  
New Class ◽  
Computer Interfaces ◽  
Human Computer Interfaces ◽  
Proposed Model ◽  
Single User ◽  
Block Based

Hardware and software technologies have given rise to a new class of human-computer interfaces that both explores multiple modalities and allows for multiple collaborating users. When compared to the development of traditional single-user WIMP (windows, icons, menus, pointer)-based applications, however, applications supporting the seamless integration of multimodal-multiuser interactions bring new specification and runtime requirements. In this thesis, with the aim of assisting the specification of multimedia applications that integrate multimodal-multiuser interactions, we: (1) propose the MMAM (Multimodal-Multiuser Authoring Model); (2) present three different instantiations of it (in NCL, HTML, and a block-based syntax); and (3) evaluate the proposed model through a user study. MMAM enables programmers to design and ponder different solutions for applications with multimodal-multiuser requirements. Its instantiations served as proofs of concept about the feasibility of our model and enabled us to perform the user study. The user study focused on capturing evidence of both the user understanding and the user acceptance of the proposed model. 94.47% of the participants gave positive answers to the block-based representation TAM questions, whereas 75.17% of them gave positive answers to the instantiations-related questions.

International Rubber Science Hall of Fame Inductee

2008 ◽  
Vol 81 (2) ◽  
pp. 1-6
Author(s):  
Geoff Holden
Keyword(s):  
Anionic Polymerization ◽  
Graft Copolymers ◽  
Polymeric Materials ◽  
Thermoplastic Elastomer ◽  
Polymer Science ◽  
Living Anionic Polymerization ◽  
New Class ◽  
Vulcanized Rubber ◽  
Hall Of Fame ◽  
American Scientist

Abstract Citation* - American scientist, chemist. Dr. Ralph Milkovich was a pioneer in anionic polymerization and heterophase polymer science. He demonstrated the concept of living anionic polymerization. He prepared the first poly(styrene-block-isoprene-block-styrene) thermoplastic elastomer, exhibiting the properties of a vulcanized rubber but processible as a thermoplastic. He also prepared a new class of polymeric materials, macromonomers, useful for the syntheses of well-defined, comb-type graft copolymers.

In Situ microscopy of the anodic etching of silicon

1995 ◽  
Vol 53 ◽  
pp. 232-233
Author(s):  
Frances M. Ross ◽  
Peter C. Searson
Keyword(s):  
Composite Structures ◽  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
Selective Etching ◽  
Silicon On Insulator ◽  
Second Phase ◽  
Porous Layers ◽  
New Class ◽  
Porous Semiconductors

Porous semiconductors represent a relatively new class of materials formed by the selective etching of a single or polycrystalline substrate. Although porous silicon has received considerable attention due to its novel optical properties1, porous layers can be formed in other semiconductors such as GaAs and GaP. These materials are characterised by very high surface area and by electrical, optical and chemical properties that may differ considerably from bulk. The properties depend on the pore morphology, which can be controlled by adjusting the processing conditions and the dopant concentration. A number of novel structures can be fabricated using selective etching. For example, self-supporting membranes can be made by growing pores through a wafer, films with modulated pore structure can be fabricated by varying the applied potential during growth, composite structures can be prepared by depositing a second phase into the pores and silicon-on-insulator structures can be formed by oxidising a buried porous layer. In all these applications the ability to grow nanostructures controllably is critical.

The microtubule associated protein (MAP) tau forms a new class of triple-stranded left-hand helical fibrous protein polymer

1992 ◽  
Vol 50 (1) ◽  
pp. 540-541
Author(s):  
G. C. Ruben ◽  
K. Iqbal ◽  
I. Grundke-Iqbal ◽  
H. Wisniewski ◽  
T. L. Ciardelli ◽  
...  
Keyword(s):  
Axial Ratio ◽  
Normal Structure ◽  
Paired Helical Filaments ◽  
Left Hand ◽  
New Class ◽  
Protein Polymer ◽  
Fibrous Protein ◽  
Protein Map ◽  
Neurotransmitter Transport ◽  
Alzheimer Neurofibrillary Tangles

In neurons, the microtubule associated protein, tau, is found in the axons. Tau stabilizes the microtubules required for neurotransmitter transport to the axonal terminal. Since tau has been found in both Alzheimer neurofibrillary tangles (NFT) and in paired helical filaments (PHF), the study of tau's normal structure had to preceed TEM studies of NFT and PHF. The structure of tau was first studied by ultracentrifugation. This work suggested that it was a rod shaped molecule with an axial ratio of 20:1. More recently, paraciystals of phosphorylated and nonphosphoiylated tau have been reported. Phosphorylated tau was 90-95 nm in length and 3-6 nm in diameter where as nonphosphorylated tau was 69-75 nm in length. A shorter length of 30 nm was reported for undamaged tau indicating that it is an extremely flexible molecule. Tau was also studied in relation to microtubules, and its length was found to be 56.1±14.1 nm.

Study of segregation in La1.8Sr0.2CuO4 superconductor by STEM-EDS microanalysis

1987 ◽  
Vol 45 ◽  
pp. 54-55
Author(s):  
T. F. Kelly ◽  
P. J. Lee ◽  
E. E. Hellstrom ◽  
D. C. Larbalestier
Keyword(s):  
Rare Earth ◽  
High Field ◽  
Transport Current ◽  
Total Thickness ◽  
New Class ◽  
Ceramic Superconductors ◽  
Current Densities ◽  
Group Ii ◽  
Eds Microanalysis

Recently there has been much excitement over a new class of high Tc (>30 K) ceramic superconductors of the form A1-xBxCuO4-x, where A is a rare earth and B is from Group II. Unfortunately these materials have only been able to support small transport current densities 1-10 A/cm2. It is very desirable to increase these values by 2 to 3 orders of magnitude for useful high field applications. The reason for these small transport currents is as yet unknown. Evidence has, however, been presented for superconducting clusters on a 50-100 nm scale and on a 1-3 μm scale. We therefore planned a detailed TEM and STEM microanalysis study in order to see whether any evidence for the clusters could be seen.A La1.8Sr0.2Cu04 pellet was cut into 1 mm thick slices from which 3 mm discs were cut. The discs were subsequently mechanically ground to 100 μm total thickness and dimpled to 20 μm thickness at the center.

Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

1996 ◽  
Vol 54 ◽  
pp. 160-161
Author(s):  
J. Fink
Keyword(s):  
Electronic Structure ◽  
Conducting Polymers ◽  
Conjugated Polymers ◽  
Electron Acceptors ◽  
Electron Donors ◽  
Light Emitting ◽  
One Dimensional ◽  
New Class ◽  
Electrical Conductivities ◽  
Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

Solvent-assisted osmium staining of butyl acrylate and ethylene-propylene-diene in a styrene acrylonitrile matrix

1993 ◽  
Vol 51 ◽  
pp. 900-901 ◽  
Author(s):  
Gudrun A. Hutchins
Keyword(s):  
Butyl Acrylate ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Staining Procedure ◽  
Reactive Site ◽  
Ethylene Propylene ◽  
Minimal Distortion ◽  
Styrene Acrylonitrile ◽  
Engineering Polymers ◽  
Effective Reaction

In order to optimize the toughening effect of elastomers in engineering polymers, it is necessary to characterize the size, morphology and dispersion of the specific elastomer within the polymer matrix. For unsaturated elastomers such as butadiene or isoprene, staining with osmium tetroxide is a well established procedure. The residual carbon-carbon double bond in these materials is the reactive site and forms a 1,2-dilato complex with the OsO4. Incorporation of osmium tetroxide into the elastomer not only produces sufficient contrast for TEM, but also crosslinks the elastomer sufficiently so that ultramicrotomy can be accomplished at room temperature with minimal distortion.Blends containing saturated elastomers such as butyl acrylate (BA) and ethylene propylene diene monomer (EPDM) cannot be stained directly with OsO4 because effective reaction sites such as C=C or -NH2 are not available in sufficient number. If additional reaction sites can be introduced selectively into the elastomer by a chemical reaction or the absorption of a solvent, a modified, two-step osmium staining procedure is possible.

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