Resonant microstrings show promise as a new analytical tool for thermal characterization of polymers with only few nanograms of sample. The detection of the glass transition temperature () of an amorphous poly(d,l-lactide) (PDLLA) and a semicrystalline poly(l-lactide) (PLLA) is investigated. The polymers are spray coated on one side of the resonating microstrings.
View Article and Find Full Text PDFElectroactive polymer (EAP) actuators are electrically responsive materials that have several characteristics in common with natural muscles. Thus, they are being studied as 'artificial muscles' for a variety of biomimetic motion applications. EAP materials are commonly classified into two major families: ionic EAPs, activated by an electrically induced transport of ions and/or solvent, and electronic EAPs, activated by electrostatic forces.
View Article and Find Full Text PDFThe conductivity properties of electro-optic, photoaddressable, dense bis-azo chromophore polymer films are investigated by using samples corona poled at various temperatures. A dielectric spectrometer is applied to measure the frequency dependence of the conductivity at different temperatures before and after heating the material to above the glass transition temperature. The results show that the orientation of the chromophores changes the charge-carrier mobility.
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