Phase transition property

Shape Dependence of Swelling and Phase Transition Properties. 17... 

In addition, the unusual shape-dependent swelling and phase transition properties observed recently in ionized NIPA gels have been reviewed. Although the mechanism responsible for these phenomena is still open to discussion, these results show that an important role is played by the surface state of ionized gels in determining the swelling equilibrium. 

Table 3.14. Molecular weights and Tg of PE-R as well as phase transition property of monomers.

Phase transition properties Melting point at 101.3 kPa (1 atm) O.OOOX... 

Phase-Transition Properties Properties of physical systems such as materials associated with their transition from one phase to another, e.g., from liquid to solid phase. Also called Phase Transition. 

More recently we utilized the well-known temperature-induced volume phase transition properties of poly(N-isopropylacrylamide) (PNIPAM) (73-75) to create novel CCA materials with variable sphere size and variable array periodicity (76). In water below 30°C, PNIPAM is hydrated and swollen, but when heated above its lower critical solution temperature ( 32 C) it undergoes a reversible volume phase transition to a collapsed, dehydrated state. The temperature increase causes the polymer to expel water and shrink into a more hydrophobic polymer state. 

Other Physical Methods.- The technique of scanning densito metry has been applied to studies of the packing and phase transition properties of a variety of phospholipids and of the... 

Heat Capacity, Entropies, and Some Phase Transition Properties of Organic Compounds In the Liquid and Solid Phases Journal of Physical and Chemical Reference Data, Volume 13, Supplement No. 1. 1984. (266 pp.)... 

Tsutsui, H. and Akashi, R. (2006) Effects of pigments on the volume-phase-transition properties of N-isopropylactylamide gels as light-modulahon materials, J.Polym. Sci. A - Polym. Chem., 44, 4644—55. 

The phospholipid (33) has been synthesized by condensation of 1,2-dipalmitoyl- -glycerol and 2,3 4--tri-0-benzyl-D-glucose with the cyclic enediol reagent (34-) The product was used for studies of bilayer formation and associated phase-transition properties of aqueous dispersions of phosphatidylglucoses. A novel platelet activating... 

The NDE method cannot be applied to studies of the nematic phase because the strong electric field causes hydrodynamic flows that destroy the nematic order. This is not the case for the isotropic phase, if the conductivity is low enough. It is well known that some nematiclike short-range order survives to the isotropic phase that influence many properties in the neighborhood of Strong influence of the short-range orientational order on the phase transition properties is discussed in Ref. 109. Especially the Kerr effect, the Cotton-Mouton effect, the... 

Finally, it should be mentioned that the chiral additive used to create a chiral nematic phase does not have to be a mesogen itself - it has to be soluble at reasonable concentration levels to produce the desired pitch, but since it is now acting equally as an impurity, the normal phase transition properties of the host material may also be altered. Chiral nematic liquid crystals are highly sensitive in their optical properties, and may therefore be used as contaminant detectors. Equally photoresponsive additives, such as azo-based dyes, may be incorporated into a chiral nematic structure and on photoexcitation they change shape since they then behave as an impurity they can easily alter the pitch or selective reflection properties. Such effects are normally reversible because of the trans-cis and cis-trans back reactions available. This gives a simple imaging device. 

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