unidirectional effect heat-induced memory effect is classified into new materials called smart. Polymers with thermal memory effect are new materials, whose applications are being studied recently in different fields of science (eg medicine), communications and entertainment.
reported systems are currently used commercially. However, the possibility of scheduling other polymers are present, due to the amount of copolymers can be designed: the possibilities are almost infinitas.Los polymers with thermal memory effect are those polymers that respond to external stimuli and because of this are capacity to change its shape. The heat-induced memory effect is a combination of proper processing and system programming.
This effect can be observed in polymers with very different chemical composition, which opens a great opportunity to aplicaciones.En the first step polymers are processed by common techniques such as injection or extrusion, thermoforming, at a temperature ( Talta) to which the polymer melts, resulting in a final form called "permanently."
The next step is called system programming and includes heating the sample to a transition temperature (TTrans). At that temperature the polymer is deformed, reaching a form called "temporary." Immediately after the temperature is lowered the sample.
The final step includes the recovery effect of permanently. The sample is heated to the temperature of transition (TTrans) and soon observed the recovery of permanently.
This effect is not a natural property of the polymer, but results from an appropriate programming of the system with the right chemistry.
For a polymer this is necessary for this effect has two components at the molecular level: links (chemical or physical) to determine the permanent and segments "triggers" TTrans for a temporary fix.
Maria linarez 19881179 EES
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