Search results
Results from the WOW.Com Content Network
Crystallization affects optical, mechanical, thermal and chemical properties of the polymer. The degree of crystallinity is estimated by different analytical methods and it typically ranges between 10 and 80%, with crystallized polymers often called "semi-crystalline". The properties of semi-crystalline polymers are determined not only by the ...
Some polymer solutions also have a lower critical solution temperature (LCST) or lower bound to a temperature range of partial miscibility. As shown in the diagram, for polymer solutions the LCST is higher than the UCST, so that there is a temperature interval of complete miscibility, with partial miscibility at both higher and lower temperatures.
Polymers have both a melting temperature T m and a glass transition temperature T g. Above the T m, the polymer chains lose their molecular ordering and exhibit reptation, or mobility. Below the T m, but still above the T g, the polymer chains lose some of their long-range mobility and can form either crystalline or amorphous regions. In this ...
Topochemical polymerization provides a potential solution to yield high-quality polymer single crystals. If the polymer is still mono crystalline, the transformation from single-crystal monomer to polymer is called single-crystal-to-single-crystal (SCSC) transformation, [ 14 ] which required a more sophisticated design than normal topochemical ...
The positive temperature phase change allows centrifugal and absorption chillers as well as the conventional reciprocating and screw chiller systems or even lower ambient conditions utilizing a cooling tower or dry cooler for charging the TES system. The temperature range offered by the PCM technology provides a new horizon for the building ...
The lower critical solution temperature (LCST) or lower consolute temperature is the critical temperature below which the components of a mixture are miscible in all proportions. [ 1 ] [ 2 ] The word lower indicates that the LCST is a lower bound to a temperature interval of partial miscibility, or miscibility for certain compositions only.
As a result of the refractive index periodicity, these systems diffract light. By taking advantage of the polymer's shape memory effect, it is possible to reprogram the lattice parameter of the structure and consequently tune its diffractive behavior. Another application of SMPs in photonics is shape changing random lasers. [31]
They are UV stable, in contrast to other bioplastics from polymers such as polylactic acid, partial ca. temperatures up to 180 °C, and show a low permeation of water. The crystallinity can lie in the range of a few to 70%.