Irreversible temperature-responsive formation of high-strength hydrogel from an enantiomeric mixture of starburst triblock copolymers consisting of 8-arm PEG and PLLA or PDLA

2008 ◽  
Vol 46 (18) ◽  
pp. 6317-6332 ◽  
Author(s):  
Koji Nagahama ◽  
Kanae Fujiura ◽  
Shunsuke Enami ◽  
Tatsuro Ouchi ◽  
Yuichi Ohya
Keyword(s):  
Triblock Copolymers ◽  
High Strength ◽  
Temperature Responsive

scholarly journals Internal Nanoparticle Structure of Temperature-Responsive Self-Assembled PNIPAM-b-PEG-b-PNIPAM Triblock Copolymers in Aqueous Solutions: NMR, SANS, and Light Scattering Studies

Langmuir ◽  
2016 ◽  
Vol 32 (21) ◽  
pp. 5314-5323 ◽  
Author(s):  
Sergey K. Filippov ◽  
Anna Bogomolova ◽  
Leonid Kaberov ◽  
Nadiia Velychkivska ◽  
Larisa Starovoytova ◽  
...  
Keyword(s):  
Light Scattering ◽  
Aqueous Solutions ◽  
Triblock Copolymers ◽  
Temperature Responsive ◽  
Self Assembled ◽  
Nanoparticle Structure

Diverse effect of PEO–PPO–PEO and PPO–PEO–PPO triblock copolymers on temperature responsive behavior of luminescent hard–soft colloids

2011 ◽  
Vol 392 (1) ◽  
pp. 343-349 ◽  
Author(s):  
Asiya Mustafina ◽  
Julia Elistratova ◽  
Lucia Zakharova ◽  
Yuliana Kudryashova ◽  
Olga Bochkova ◽  
...  
Keyword(s):  
Triblock Copolymers ◽  
Temperature Responsive ◽  
Responsive Behavior ◽  
Soft Colloids

UV Light and Temperature Responsive Supramolecular ABA Triblock Copolymers via Reversible Cyclodextrin Complexation

2013 ◽  
Vol 46 (3) ◽  
pp. 1054-1065 ◽  
Author(s):  
Bernhard V. K. J. Schmidt ◽  
Martin Hetzer ◽  
Helmut Ritter ◽  
Christopher Barner-Kowollik
Keyword(s):  
Uv Light ◽  
Triblock Copolymers ◽  
Temperature Responsive ◽  
Cyclodextrin Complexation

Structural and Rheological Properties of Temperature-Responsive Amphiphilic Triblock Copolymers in Aqueous Media

2017 ◽  
Vol 121 (18) ◽  
pp. 4885-4899 ◽  
Author(s):  
Josefine Eilsø Nielsen ◽  
Kaizheng Zhu ◽  
Sverre Arne Sande ◽  
Lubomír Kováčik ◽  
Dušan Cmarko ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Triblock Copolymers ◽  
Aqueous Media ◽  
Temperature Responsive

Rubber Reinforcement and its Classification

2007 ◽  
Vol 80 (3) ◽  
pp. 533-544 ◽  
Author(s):  
G. R. Hamed
Keyword(s):  
Size Range ◽  
Triblock Copolymers ◽  
Average Distance ◽  
High Strength ◽  
Nano Composites ◽  
Nano Composite ◽  
Kinetics And Thermodynamics ◽  
Commercial Use ◽  
Insoluble Particles ◽  
Before And After

Abstract Principles of rubber reinforcement are discussed and new nomenclature is proposed to classify reinforced rubbers. The engineering tensile strength σb of amorphous, gum, non-crystallizable rubbers is only about σb≈3 MPa. These have no commercial use. However, if such rubbers contain enough stiff (hard or rigid) “entities” of density ρ and specific surface area S, such that 600/ρ m2/mL>S>60/ρ m2/mL, then σb>20 20 MPa. These rubbers are considered highly reinforced. The value of S for a stiff “entity” is largely dependent on its characteristic smallest dimension, d. For spheres or rods, d is diameter, and for plates, d is thickness. For all three shapes, the range of d corresponding to the limits of S given previously is approximately 100 nm>d>1 nm. Sometimes, the prefix nano- has been used to designate materials that contain stiff “entities” in this range of d. Other times, the prefix nano- has denoted a smaller range of d, 10 nm>d>1 nm. Thus, the term nano- is ambiguous in the literature. It is proposed to divide the size range, 1 nm<d<100 nm, of stiff “entities” into two ranges with different designations. When 10 nm>d>1 nm, the prefix proposed is nano-, and when 100 nm>d>10 nm, meso- is proposed as the prefix. This division may seem superfluous and arbitrary, but there is scientific merit for it. The way that the stiff “entities” come about provides criteria for further categorization. If the “entities” are (insoluble) particles that have similar d before and after incorporation (i.e., d is largely pre-determined) into an elastomer, then “composite” is the suffix proposed. But, if the stiff “entities” evolve and d depends on the kinetics and thermodynamics of phase separation, then the suffix is “structured.” Nomenclature for four types of rubber are then proposed: meso-composite, meso-structured, nano-structured and nano-composite. Commercial examples of the first three are known: black-filled SBR vulcanizates (meso-composite, σb≈20–30 MPa), SBS triblock copolymers (mesostructured, σb≈20–30 MPa), and elastomeric ionomers (nano-structured, σb≈50–60 MPa). Both meso-rubbers need about 20–25% (by volume) stiff “entity” to attain high reinforcement, whereas, only 2% stiff “entity” (ionic domains) imparts high reinforcement to nano-structured ionomers. Highly reinforced meso-rubber contains a higher concentration of stiff “entity” than that present in highly reinforced nano-rubber. However, in both meso- and nano-rubbers, the average distance between stiff “entities” is about 5 nm. This distance is similar to the spacing of crosslinks in vulcanizates that are optimally crosslinked. To the author's knowledge, no nano-composite rubber that is highly reinforced has been made. Nonetheless, the existence of high strength nano-structured ionomers suggests that highly reinforced nano-composites may be possible.

Decomposition of the metastable beta titanium alloy Ti-15-3

1983 ◽  
Vol 41 ◽  
pp. 264-265
Author(s):  
Y. L. Chen ◽  
S. Fujlshiro
Keyword(s):  
Low Cost ◽  
High Strength ◽  
Alpha Phase ◽  
Thick Sheet ◽  
Omega Phase ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Beta Matrix ◽  
Metastable Beta ◽  
Very High

Metastable beta titanium alloys have been known to have numerous advantages such as cold formability, high strength, good fracture resistance, deep hardenability, and cost effectiveness. Very high strength is obtainable by precipitation of the hexagonal alpha phase in a bcc beta matrix in these alloys. Precipitation hardening in the metastable beta alloys may also result from the formation of transition phases such as omega phase. Ti-15-3 (Ti-15V- 3Cr-3Al-3Sn) has been developed recently by TIMET and USAF for low cost sheet metal applications. The purpose of the present study was to examine the aging characteristics in this alloy.The composition of the as-received material is: 14.7 V, 3.14 Cr, 3.05 Al, 2.26 Sn, and 0.145 Fe. The beta transus temperature as determined by optical metallographic method was about 770°C. Specimen coupons were prepared from a mill-annealed 1.2 mm thick sheet, and solution treated at 827°C for 2 hr in argon, then water quenched. Aging was also done in argon at temperatures ranging from 316 to 616°C for various times.

Effects of cooling rate on the mechanical properties of dual phase treated vanadium steels

1983 ◽  
Vol 41 ◽  
pp. 220-221
Author(s):  
L.J. Chen ◽  
H.C. Cheng ◽  
J.R. Gong ◽  
J.G. Yang
Keyword(s):  
Mechanical Properties ◽  
Cooling Rate ◽  
Automobile Industry ◽  
High Strength ◽  
Weight Percent ◽  
Low Alloy Steels ◽  
Dual Phase ◽  
Resource Requirement ◽  
Alloy Steels ◽  
Potential Weight

For fuel savings as well as energy and resource requirement, high strength low alloy steels (HSLA) are of particular interest to automobile industry because of the potential weight reduction which can be achieved by using thinner section of these steels to carry the same load and thus to improve the fuel mileage. Dual phase treatment has been utilized to obtain superior strength and ductility combinations compared to the HSLA of identical composition. Recently, cooling rate following heat treatment was found to be important to the tensile properties of the dual phase steels. In this paper, we report the results of the investigation of cooling rate on the microstructures and mechanical properties of several vanadium HSLA steels.The steels with composition (in weight percent) listed below were supplied by China Steel Corporation: 1. low V steel (0.11C, 0.65Si, 1.63Mn, 0.015P, 0.008S, 0.084Aℓ, 0.004V), 2. 0.059V steel (0.13C, 0.62S1, 1.59Mn, 0.012P, 0.008S, 0.065Aℓ, 0.059V), 3. 0.10V steel (0.11C, 0.58Si, 1.58Mn, 0.017P, 0.008S, 0.068Aℓ, 0.10V).

The Nature of Delta Phase Precipitation in Inconel 718

1982 ◽  
Vol 40 ◽  
pp. 724-725
Author(s):  
L. S. Lin ◽  
C. C. Law
Keyword(s):  
Inconel 718 ◽  
Base Alloy ◽  
High Strength ◽  
Physical Metallurgy ◽  
Nickel Base Alloy ◽  
Phase Precipitation ◽  
Weight Percentage ◽  
Delta Phase ◽  
The Subject ◽  
Nickel Base

Inconel 718, a precipitation hardenable nickel-base alloy, is a versatile high strength, weldable wrought alloy that is used in the gas turbine industry for components operated at temperatures up to about 1300°F. The nominal chemical composition is 0.6A1-0.9Ti-19.OCr-18.0Fe-3Mo-5.2(Cb + Ta)- 0.1C with the balance Ni (in weight percentage). The physical metallurgy of IN 718 has been the subject of a number of investigations and it is now established that hardening is due, primarily, to the formation of metastable, disc-shaped γ" an ordered body-centered tetragonal structure (DO2 2 type superlattice).

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