|학술대회||2004년 가을 (10/08 ~ 10/09, 경북대학교)|
|권호||29권 2호, p.633|
|제목||The Actuation Behavior in polyurethanes Containing Various Types of Montmorillonite|
|초록||Electrostriction is the phenomenon that material is strained due to both Maxwell stress effect and electrostriction effect developed by the applied voltage. Polyurethanes(PUs) were known as electrostrictive materials and they showed relatively large displacement among the electro statically stricted polymers.1 We dispersed montmorillonite (MMT) into the PU matrix to improve the displacement of PU.2 PUs were prepared by using prepolymer method. And three types of MMT, Cloisite Na+, Cloisite 20A and Cloisite 30B, were dispersed by stirring in PU solution for about 7days. The contents of each MMT were 1, 3, 5wt% to pure PU matrix. From X-ray diffraction(XRD) results of PU/MMT nanocomposites, it could be known that silicate layers of organoclay were completely exfoliated in the polyurethane matrix. Also we used compliant PU carbon black electrode for the measurement of displacement in the electric field. Fig. 1 shows that the dielectric constant increased with increasing the amount of MMT. And Fig. 2 shows the on-off system when the electric field(8.5MV/m) was applied. Under the same electric field, PU/MMT nanocomposites had larger displacement than pure PU. And the displacement of PU/MMT nanocomposites increased with increasing of MMT contents. Especially the PU/MMT nanocomposites with Cloisite 30B had the largest displacement.
Fig. 1. Dielectric constants according Fig. 2. Effect of the input voltage.
to MMT contents.
1. Yoseph Bar-Cohen, Electroactive Polymer(EAP) Actuators as Artificial Muscles, SPIE Press, 2001, Chap.1.
2. T. K. Chen, Y. I. Tien and K. H. Wei, Polymer, 41, 1345 (2000).
|저자||최화정, 강혜란, 김범호, 박한수, 정영대, 정해도, 이장우, 조남주|
|키워드||Electrostriction; Polyurethane; Montmorillonite|