Glassy microdomain

In our experiments, the quench from a swollen to a glassy state has been achieved within tens of seconds, and has been shown not to alter the phase separation in a swollen state[49]. Figure 17 compares surface structures in SB41 films that have been exposed to a relative vapor pressure p/po of 72% and of 80%. With an increase of the solvent concentration, the in-plane order of the microdomains... 

Carbon molecular sieves, or carbogoric sieves are amorphous materials made by pyrolyz-ing coal, coconut shells, pitch, phenol-formaldehyde resin, or other polymers. EKslocations of aromatic microdomains in a glassy matrix give their porosity. Pores are slit-shaped. Pore structure is controlled by the temperature of the pyrolysis. Pore widths range from 3 A to 10 A. Acarbogenic sieve made from polyfurfuryl alcohol and combined with silica-alumina was selective for monomethylamine production from methanol and ammonia [54]. 

Chapter 19 considers the effects of polymer-penetrant interactions on the sorption of aromatic penetrants into a polyurethane thermoplastic elastomer(91). A direct liquid immersion approach was used, so the heat transfer problems noted above should not be important. Nevertheless, non Fickian phenomena are still observed. Unlike simple elastomers, thermoplastic elastomers achieve their crosslinked natures by formation of microdomains of either crystalline or glassy hard segments. The anomalous sorption behavior presumably reflects interactions of the solvents with these microdomains (93-94). 

It was found that when the solution-cast films are stretched at temperature greater than Tg, liquid crystalline microdomains can support part of the elastic extension and, at the same time, deform to result in a long-range orientation of azobenzene mesogens. The liquid crystal orientation is retained in the relaxed film at r < Tg, which creates a thermoplastic elastomer whose glassy micro-... 

The rubbery plateau also represents an indicator of miscibility (Badia et al. 2015). Linear triblock copolymers composed of poly(n-butyl acrylate) and polystyrene (PS-PBA-PS) have phase-separated morphologies exhibiting two rnbbery plateaux (Pakula et al. 2011). The first plateau lies between the Tg of the PBA blocks and the Tg of the PS blocks in this region, the glassy PS microdomains act like physical crosslinks for the flexible PBA blocks. The second rubbery plateau starts after the Tg of PS and continues until the order-disorder transition, where the microdomain strncture transforms into a disordered homogeneous phase (Han et al. 1989). The length and the storage modnlns of the rubbery plateau depend on the molecular... 

It is clear from many experimental results that crystalline blocks confined in isolated nanodomains surrounded by glassy (or hard) matrices show unique crystal orientations as compared with those by soft matrices (Section 10.3.3.). However, the physical properties of such block copolymers with crystalline microdomain structures have scarcely been investigated up to now. 

Khanna V, Ruokolainen J, Kramer EJ, Hahn SF. Deformation and fracture of lamellar and cylindrical block copolymers with unentangled glassy matrices Effect of chain architecture and microdomain orientation. Macromoleeules 2006 39(13) 4480-4492. 

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