Piezoelectric ultrathin polymer films synthesized by electrostaticself-assembly processing

摘要

Ultrathin piezoelectric composite films composed of poly(sodium4-styrenesolfonate) (PSS) and poly(diallyldimethylammonium chloride) (PDDA)were synthesized using the electrostatic self-assembly (ESA) process. TheESA-processed PSS/PDDA films have a layer-by-layer laminated structure, andexhibit a piezoelectric response directly without electric field poling. Themeasured piezoelectric coefficientd33= 6.0pCN-1. The molecularself-assembly process plays a very important role in molecular alignment,resulting in a net macroscopic polarization of the layer-by-layer structuredultrathin film, although the process is quite different from that used toform conventional piezoelectric materials. Further study concerning theprinciples governing the novel ESA processing of piezoelectric and otherfunctional films is on-going.