| |
 |
UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS Guest
2024-11-23 13:49 |
 |
|
|
|
Conference: Bucharest University Faculty of Physics 2008 Meeting
Section: Polymer Physics
Title:
The applications of liquid polymer crystals
Authors:
Irina-Elena Nicolae
Crina Turcas
Affiliation:
The National College “SF.Sava”,Bucharest
E-mail
irinanicolae2001@yahoo.com
Keywords:
application, polymer, crystals
Abstract:
An important point regarding applications is represented by liquid polymer crystals , situated at the borderline between 2 scientific domains , that of liquid crystals and the one of polymers.
The first liquid polymer crystals with industrial development are flavored polyamides or aramides( isotropy polymers) which`s most known representatives are poly phenyl terephthalamide and it`s compounds , commercialized under the name Kevlar (films and fibers).
Kevlar fibers have specific properties ( tenacity , resistance to tearing ) superior to those of steel. Because of it`s remarkable qualities : high melting and soaking points , thermal stability , excellence resistance to fire ,low density, good dielectric properties, resistance to fatigue, to bending, to tearing, Kevlar is used as a strengthening fiber for high performance composites , in aeronautics, in protection industry(armor) , high performance sports equipment, for making special fabrics, protection clothes , bulletproof waistcoats , parachutes , etc. The main problem regarding Kevlar is it`s impossibility to be used under the form of massive pieces. The synthesis and characterization of terephthalamide polystyrenes have enabled us to obtain products with high technical performances of any shapes ( films, fibers, massive part through injection, extrusion and molding).
Two chromatic polystyrenes: Xydar and Vectra. Linear thermo tropic polymers have multiple advantages, such as exceptional forming abilities, excellent mechanical properties, excellent dimensional stability, remarkable chemical inertia, even at high temperatures , low inflammability and self extinction , which make these liquid polymer crystals materials a very good choice for the chemical industry, aeronautics ,the electro technical and electronic industry.
|
|
|
|