Preparation Of Fibre-based Functionalized Materials Of Detection Of Cu(?) And Their Recognition Mechanism

In this work,from the perspective of structural design of Cu²⁺detection materials,biomass Eucalyptus fiber and synthetic acrylic fiber as the matrix respectively were used,and chemical grafting method was used to introduce recognition group of Cu²⁺onto the fibers in a controllable way to prepare visible fiber-based detection materials that can selectively recognize Cu²⁺.The detection performance and selective recognition mechanism of Cu²⁺detection materials from biomass fiber and synthetic fiber as well as the detection performance of paper-based Cu²⁺detection materials were studied.1.The eucalyptus pulp fiber?PF?was used as the matrix.The C-2,C-3hydroxyl?-OH?of Eucalyptus fiber was oxidized to aldehyde?-CHO?by sodium periodate oxidation method to prepare dialdehyde fiber?DAC?.Then Pyridine-2,6-dimethylhydrazide?PDH?containing C=O and-NH₂/-NH structure was chemically anchored on the fiber by Schiff base reaction to prepare the Eucalyptus fiber-based Cu²⁺colorimetric sensor material?DAC-PDH?.Cu²⁺was selectively recognized in the mixed metal ion solution,and the color response?white changed to green?appeared within 30 s.The detection limit of Cu²⁺was 1×10^-7 mol/L?6.4 ppb?,which was far lower than the standard of 2 ppm maximum Cu²⁺in drinking water stipulated by the World Health Organization?WHO?.The detection of DAC-PDH is suitable for a wide range of p H?2-6?.The real water sample experiment shows that DAC-PDH can detect Cu²⁺quickly in the field.2.PAN-TEPA was prepared by grafting tetraethylene pentamine?TEPA?onto pan substrate through amination reaction.PAN-TEPA was used as the precursor,and thiodiacetic acid?TDA?containing axially symmetric carboxyl?-COOH?and thioether?-S-?structure was chemically anchored on PAN-TEPA by amidation reaction to prepare PAN-TEPA-TDA.Cu²⁺was selectively identified in the mixed metal ion solution,and the color response?yellow changed to blue?appeared within 30 s.The detection limit of Cu²⁺was 1×10^-6 mol/L?64 ppb?,which was far lower than the standard of the highest Cu²⁺content in drinking water stipulated by the World Health Organization?WHO?.It has been proved that the synergism between functional groups,functional groups and fibers can achieve high selectivity and high sensitivity detection of Cu²⁺,and the general rule of selective recognition of Cu²⁺by the type and number of functional ligands has been revealed.