▎ 摘　　要

NOVELTY - Three dimensional (3D) printed part, comprises functional monomer or at least one monofunctional thermoplastic photosensitive resin monomer. The functional monomer is metal ions containing compound (I) or compound containing dynamic chemical bond. USE - The 3D printed part is useful in aerospace, medical treatment, and art design. ADVANTAGE - The 3D printed part can realize recovery of fillers and high-efficiency utilization, and helps to reduce costs. DETAILED DESCRIPTION - Three dimensional (3D) printed part, comprises functional monomer or at least one monofunctional thermoplastic photosensitive resin monomer. The functional monomer is metal ions containing compound of formula (MxRy) (I) or compound containing dynamic chemical bond. M = metal ions; R = anions; n = valence number of metal ion; and m = valence number of anion. Provided that if n/m is an integer, then x = 1 and y=n/m; and if n/m is not an integer, then x = m and y = n. INDEPENDENT CLAIMS are also included for: (I): preparing 3D printed part comprising (a) introducing functional monomers into 3D printing system to prepare self-repairing or recyclable 3D printed parts or introducing functional monomers into the 3D printing system to prepare 3D printed part with enhanced interface strength, or (b) using at least one monofunctional thermoplastic photosensitive resin monomer as one of the 3D printing raw materials to prepare recyclable 3D printing parts; #composition for preparing self-healing or recyclable parts by light-curing 3D printing, comprising photosensitive resin monomer, a photoinitiator and a functional monomer, and nanop parts. The monomer of photosensitive resin is a monofunctional photosensitive compound, preferably acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, epoxy acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, urethane acrylate, urethane methacrylate, lauryl acrylate, isobornyl acrylate, lauryl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, at least one of ethoxyethyl acrylate and/or 1,3-propanediol monoacrylate. The photoinitiator is bibenzoyl, diphenyl ethylenedione, dialkoxy acetophenone, camphorquinone, alpha -hydroxyalkylphenones, alpha -aminoalkylphenones, acylphosphine oxide, benzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, triethanolamine, N-methylethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, quinone compounds, titanocene compounds, iodonium salt compounds, sulfonium salt compound and/or triazine compound. The nanop parts are silicon dioxide, ferroferric oxide, titanium dioxide, montmorillonite, boron nitride, graphene, molybdenum disulfide, graphene oxide, and carbon nanotubes. The mass ratio of the functional monomer to the monomer of the photosensitive resin is (0.05-5):100. The mass ratio of the photoinitiator to the monomer of the photosensitive resin is (0.01-5):100. The mass ratio of the nanop parts to the monomer of the photosensitive resin is (0.01-20):100. The composition is used in the preparation of light-cured 3D printed parts; (II): composition for preparing light-cured 3D printed linear polymer parts comprising at least one photosensitive resin monomer and photoinitiator, and optional fillers. The monomer of the photosensitive resin is a monofunctional thermoplastic photosensitive resin monomer of formula (I) and (II); and (III): improving the interface strength of 3D printed part comprising (a) introducing the functional monomers into the 3D printing material system, and obtaining printed parts after 3D printing, and (b) activating the printed part obtained in step (a) to improve the interface strength of the printed part. The functional monomer is blended with other materials in the system, the other materials include polymers, and the polymer materials contain at least one of oxygen, nitrogen, sulfur, boron, and phosphorus. The 3D printing is fused deposition, selective thermal sintering, selective laser sintering, three-dimensional lithography, layered physical printing, digital light processing and/or direct writing. The activation treatment is at least one of heat treatment, light treatment, and electrical treatment. The polymer is at least one of polymer powder, polymer wire, polymer film, and liquid photosensitive resin. The polymer in the polymer powder, polymer wire and polymer film includes polylactic acid, Polyether ether ketone (RTM: Colourless organic thermoplastic polymer in polyaryletherketone family, used in engineering applications), polyurethane, polycarbonate, polymethyl methacrylate, polyvinyl alcohol, vinyl acetate-ethylene copolymer, acrylate copolymer, nylon, acrylonitrile-butadiene-styrene copolymer, and/or polyterephthalic acid plastics. The liquid photosensitive resin includes polyepoxy acrylate, unsaturated polyester, urethane acrylate, polyester acrylate, polyether acrylate, polyacrylate, and/or light-curing silicone oligomer. The photosensitive resin is obtained by polymerizing raw materials including photosensitive resin monomers. The monomer of the photosensitive resin includes acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, epoxy acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, urethane acrylate, urethane methacrylate, lauryl acrylate, lauryl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, ethoxyethyl acrylate and/or 1,3-propanediol monoacrylate. The raw material is polymerization inhibitor when liquid photosensitive resin is photoinitiator. The mass ratio of the functional monomer to the polymer is 1:(10-150). The material system also contains other components contained in the material system suitable for the corresponding 3D printing method, preferably at least one of liquid metal and pigment. R1 = H, or alkyl, cycloalkyl, heterocycle, bridged ring, polyurethane group (all are optionally substituted with hydroxy, alkoxy or norbornenyl), preferably alkoxy; R2, R3 = H, alkyl, and aryl; R, R' = H, methyl or ethyl; R'2 and R'3 = H, alkyl, and aryl; X1 = O or NR''; and R'' = H and alkyl.