1：Experimental Design and Method Selection:

The study involved synthesizing acylhydrazide-functionalized pectin (pectin AH) via hydrazinolysis and a TPE-containing copolymer via RAFT polymerization. Hydrogels were formed by cross-linking these components through acylhydrazone bonds. Methods included NMR, FT-IR, UV-Vis, PL spectroscopy, and rheology for characterization.

2：Sample Selection and Data Sources:

Apple pectin (food-grade, methoxyl esterification ~35.0%) and synthesized copolymers with varying compositions were used. Data were obtained from laboratory synthesis and instrumental analyses.

3：0%) and synthesized copolymers with varying compositions were used. Data were obtained from laboratory synthesis and instrumental analyses. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Equipment included Bruker AVANCE III 600 MHz NMR spectrometer, Varian 640-IR FT-IR spectrophotometer, UV-2550 spectrophotometer, RF-5301PC fluorescence spectrophotometer, and TA AR2000ex rheometer. Materials included pectin, DMA, DAA, DDMAT, AIBN, hydrazine hydrate, EDC·HCl, DMAP, and various solvents.

4：Experimental Procedures and Operational Workflow:

Pectin AH was prepared by reacting pectin with hydrazine hydrate in water at 40°C for 24 hours. TPE-2DDMAT was synthesized via esterification, and copolymers were polymerized using RAFT. Hydrogels were formed by mixing aqueous solutions of pectin AH and copolymer, with gelation observed over time. Characterizations involved NMR, FT-IR, UV-Vis, PL, and rheological measurements.

5：Data Analysis Methods:

Data were analyzed using instrumental software for spectral and rheological properties. Molecular weights and compositions were calculated from NMR and GPC.