Block copolymers, blends, hydrogen

Blending of Block Copolymers with Hydrogen Bonding Interactions. 201... 

Asari T, Aral S, Takano A, Matsushita Y. Archimedean tiling structures from ABA/CD block copolymer blends having intermolecular association with hydrogen bonding. Macro-molecules 2006 39 2232-2237. 

Jiang S, Gopfert A, Abetz V. Novel morphologies of block copolymer blends via hydrogen bonding. Macromolecules 2003 31 6171-6177. 

Homopolymer/Block Copolymer Blends with Controllable Hydrogen Bonding. 165... 

Block Copolymer Blends with Hydrogen Bonding. 125... 

Commercial membranes for CO2 removal are polymer based, and the materials of choice are cellulose acetate, polyimides, polyamides, polysulfone, polycarbonates, and polyeth-erimide [12]. The most tested and used material is cellulose acetate, although polyimide has also some potential in certain CO2 removal applications. The properties of polyimides and other polymers can be modified to enhance the performance of the membrane. For instance, polyimide membranes were initially used for hydrogen recovery, but they were then modified for CO2 removal [13]. Cellulose acetate membranes were initially developed for reverse osmosis [14], and now they are the most popular CO2 removal membrane. To overcome state-of-the-art membranes for CO2 separation, new polymers, copolymers, block copolymers, blends and nanocomposites (mixed matrix membranes) have been developed [15-22]. However, many of them have failed during application because of different reasons (expensive materials, weak mechanical and chemical stability, etc.). 

W. P. Gergen and S. Davison, Thermoplastic polyester/Block Copolymer Blend, U.S. Pat. 4,101,605 (1978). Blends of ABA block copolymers and crystalling polyesters. Physical IPNs with continuous interlocking networks. Selectively hydrogenated block copolymers. Thermoplastic IPNs of the block/crystal type. 

They provide an amphiphillic function in blends of dissimilar polymers, where favorable interactions exist between one of the homopolymers and one of the block copolymer segments.Hydrogenated block copolymers which reduce surface tension in polystyrene-polyoletin blends is one example. Another example is the use of a derivatized block copolymer, such as terminally carboxylated styrene-diene di-block copolymers,... 

Han SH et al. Highly asymmetric lamellar nanopattems via block copolymer blends capable of hydrogen bonding. ACS Nano 2012 6(9) 7966-7972. 

Han SH et al. Phase behavior of binary blends of block copolymers having hydrogen bonding. Macromolecules 2011 44(12) 4970 976. 

In the previous sections blends were considered in which entro-pic forces originating from different stretchings of chemically similar blocks controlled the formation of common superlattices. Besides entropic contributions, enthalpic interactions can also play a dominating role in block copolymer blending, for the same reasons as in the case of blends of homo or random copolymers. For example, hydrogen bonding or ionic interactions can force the formation of common super lattices, if, for example, a polyadd block of one block copolymer is mixed with the polybase block of another block copolymer. In such... 

Microdomains of block copolymer/ homopolymer blends 25-A-diameter Pd clusters Metal-ion precursors, introduced into cast thin films of polymer microdomains, are reduced by high pressure hydrogen 60,61... 

A block copolymer 55 consisting of a polystyrene block and a poly (CL) block was found to be an effective blending agent for the combination between polystyrene and poly(vinyl chloride). A po ybutadiene/poly(CL) block copolymer was an efficient blending agent for a mixture of polybutadiene and polyacrylonitrile. In addition, a block copolymer of poly(hydrogenated 1,4-butadiene) with poly(CL) allows a three-component mixture of polystyrene, polyethylene and poly(vinyl chloride) to be blended. 

Then we will turn our attention to blends of block copolymers where the self-assembly is dominated by multiple hydrogen bonding between complementary blocks of the two constituents. The self-assembly of some of these systems has features in common with that of star copolymers and allows one to study the consequences of this architecture for the structures formed [43-45]. 

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