Improving the High-Frequency Response of PEI-Based Earphone with Sodium Copper Chlorophyllin.

ABSTRACT: The polyetherimide diaphragm, sodium copper chlorophyllin (SCC), and copper ion coating composite used on earphones were observed to improve the high-frequency (10k-14k Hz) performance. This reinforcement phenomenon was expected to make the sound experience brighter and more diverse. By SEM observation, the mixed coating of SCC/Cu2+ on the polyethylenimine (PEI) diaphragm exhibited a planar blocky structure and was tightly bonded to the surface of the PEI polymer without the aid of colloids. The endothermic process of SCC and metal ion complexation was analyzed by isothermal titration calorimetry. The association ratios of SCC/Cu2+ and SCC/Ni2+ were 4/1 and 6/1, respectively, and the SCC/Cu2+ association yielded a stronger binding constant and more free energy. It was expected that the SCC

SUBMITTER: Li HZ 

PROVIDER: S-EPMC6983146 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature