Structure and Properties of Semicrystalline−Rubbery Multiblock Copolymers

2006 ◽  
Vol 39 (2) ◽  
pp. 667-677 ◽  
Author(s):  
Chong Min Koo ◽  
Marc A. Hillmyer ◽  
Frank S. Bates
RSC Advances ◽  
2015 ◽  
Vol 5 (106) ◽  
pp. 86980-86989 ◽  
Author(s):  
Ao Nan Lai ◽  
Yi Zhi Zhuo ◽  
Chen Xiao Lin ◽  
Qiu Gen Zhang ◽  
Ai Mei Zhu ◽  
...  

Two series of novel poly(arylene ether sulfone nitrile) (PESN) multiblock copolymers are synthesized to prepare anion exchange membranes (AEMs) for alkaline fuel cells.


Author(s):  
Ernest L. Hall ◽  
Shyh-Chin Huang

Addition of interstitial elements to γ-TiAl alloys is currently being explored as a method for improving the properties of these alloys. Previous work in which a number of interstitial elements were studied showed that boron was particularly effective in refining the grain size in castings, and led to enhanced strength while maintaining reasonable ductility. Other investigators have shown that B in γ-TiAl alloys tends to promote the formation of TiB2 as a second phase. In this study, the microstructure of Bcontaining TiAl alloys was examined in detail in order to describe the mechanism by which B alters the structure and properties of these alloys.


Author(s):  
E. Baer

The most advanced macromolecular materials are found in plants and animals, and certainly the connective tissues in mammals are amongst the most advanced macromolecular composites known to mankind. The efficient use of collagen, a fibrous protein, in the design of both soft and hard connective tissues is worthy of comment. Very crudely, in bone collagen serves as a highly efficient binder for the inorganic hydroxyappatite which stiffens the structure. The interactions between the organic fiber of collagen and the inorganic material seem to occur at the nano (scale) level of organization. Epitatic crystallization of the inorganic phase on the fibers has been reported to give a highly anisotropic, stress responsive, structure. Soft connective tissues also have sophisticated oriented hierarchical structures. The collagen fibers are “glued” together by a highly hydrated gel-like proteoglycan matrix. One of the simplest structures of this type is tendon which functions primarily in uniaxial tension as a reinforced elastomeric cable between muscle and bone.


Author(s):  
Richard J. Spontak ◽  
Steven D. Smith ◽  
Arman Ashraf

Block copolymers are composed of sequences of dissimilar chemical moieties covalently bonded together. If the block lengths of each component are sufficiently long and the blocks are thermodynamically incompatible, these materials are capable of undergoing microphase separation, a weak first-order phase transition which results in the formation of an ordered microstructural network. Most efforts designed to elucidate the phase and configurational behavior in these copolymers have focused on the simple AB and ABA designs. Few studies have thus far targeted the perfectly-alternating multiblock (AB)n architecture. In this work, two series of neat (AB)n copolymers have been synthesized from styrene and isoprene monomers at a composition of 50 wt% polystyrene (PS). In Set I, the total molecular weight is held constant while the number of AB block pairs (n) is increased from one to four (which results in shorter blocks). Set II consists of materials in which the block lengths are held constant and n is varied again from one to four (which results in longer chains). Transmission electron microscopy (TEM) has been employed here to investigate the morphologies and phase behavior of these materials and their blends.


Author(s):  
C.K. Wu ◽  
P. Chang ◽  
N. Godinho

Recently, the use of refractory metal silicides as low resistivity, high temperature and high oxidation resistance gate materials in large scale integrated circuits (LSI) has become an important approach in advanced MOS process development (1). This research is a systematic study on the structure and properties of molybdenum silicide thin film and its applicability to high performance LSI fabrication.


1991 ◽  
Vol 88 ◽  
pp. 411-420 ◽  
Author(s):  
D Peeters ◽  
G Leroy

1997 ◽  
Vol 7 (10) ◽  
pp. 1489-1497 ◽  
Author(s):  
A. N. Semenov

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