Thermal insulation composite fluorescent material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of high polymer materials, and particularly discloses a thermal insulation composite fluorescent material as well as a preparation method and application thereof. The thermal insulation composite fluorescent material comprises the following raw material components in parts by mass: 90-110 parts of PVC resin, 2-10 parts of hollow nanoparticles, 1.5-5 parts of a heat stabilizer and 0.8-1.2 parts of a lubricant, wherein the hollow nanoparticles comprise hollow silicon dioxide core spheres and hollow silicon dioxide spheres attached to the surfaces of the hollow silicon dioxide core spheres. The heat-preservation and heat-insulation composite fluorescent material has excellent heat-preservation and heat-insulation functions and an excellent photoluminescence effect, a pipeline material prepared from the heat-preservation and heat-insulation composite fluorescent material can have excellent heat-preservation performance, the quality of a pipeline can be monitored, and the defects in the prior art are overcome.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and particularly discloses a thermal insulation composite fluorescent material, a preparation method and an application thereof. Background Art

[0002] The thermal insulation performance of pipes directly affects energy efficiency, especially in high-energy-consuming industries such as hot water, steam, and electricity, where heat loss from pipes often accounts for a large proportion of energy consumption. Therefore, improving pipe insulation performance and reducing heat loss are crucial for improving energy efficiency.

[0003] Currently, pipeline insulation primarily relies on external insulation layers to enhance thermal insulation. These materials include polyurethane foam, glass wool, and mineral wool. However, while traditional external insulation materials can improve pipeline insulation performance to a certain extent, they often face a series of challenges, including complex construction, unstable results, poor environmental performance, and increased pipeline size and weight. Therefore, developing an innovative pipeline material that can improve pipeline insulation performance while simplifying construction processes, reducing costs, and possessing other functionalities has become a pressing technical challenge. Summary of the Invention

[0004] In light of this, the present invention provides a thermal insulation composite fluorescent material, its preparation method, and its application. This material not only exhibits excellent thermal insulation but also exhibits a superior photoluminescence effect. Pipes made with this material not only address the poor thermal insulation performance of existing pipeline materials but also provide early warnings of pipeline damage or leaks through fluorescence, thereby enabling intelligent monitoring of pipeline material quality.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The first aspect of the present invention provides a thermal insulation composite fluorescent material, comprising the following raw material components in parts by weight: 90-110 parts of PVC resin, 2-10 parts of hollow nanoparticles, 1.5-5 parts of a thermal stabilizer, and 0.8-1.2 parts of a lubricant; wherein the hollow nanoparticles include a hollow silica core ball and hollow silica spheres attached to the surface thereof.

[0006] Compared to the prior art, the thermal insulation composite fluorescent material designed by the present invention contains hollow nanoparticles, which can not only enhance the mechanical strength of PVC resin, but also, due to its special morphology, can evenly adsorb and disperse the auxiliary agent, thereby enhancing the compatibility of PVC resin with heat stabilizers and lubricants. In addition, the hollow nanoparticles have a large specific surface area and a special hollow structure, which can encapsulate more air, thereby significantly enhancing the thermal insulation performance of the composite material and reducing heat loss. It also has excellent photoluminescence properties and can form a significant fluorescence effect under ultraviolet light irradiation, which can be used to assist in monitoring the quality of pipelines. The thermal insulation composite fluorescent material provided by the present invention not only has excellent thermal insulation performance, which makes up for the shortcomings of the prior art, but also has special photoluminescence properties. When it is used to prepare pipelines, it can be used to give an early warning through fluorescence when the pipeline is damaged or leaking, thereby realizing intelligent monitoring of pipeline quality, and providing a new design idea for the research and development of pipeline materials.

[0007] Preferably, the diameter of the hollow silica core sphere is 200nm-400nm.

[0008] Preferably, the hollow silica spheres are 100nm-200nm.

[0009] The present invention controls the particle size of the hollow silica core ball and the hollow silica sphere to further control the size of the protrusions on the outer shell of the hollow nanoparticle, so that the protrusions on the surface of the hollow nanoparticle are uniform and of appropriate size, the constructed micro / nano hierarchical structure is more reasonable, and it is more conducive to forming a surface with a certain roughness, thereby obtaining a better hydrophobic effect.

[0010] Preferably, the water contact angle of the hollow nanoparticles is 150°-160°.

[0011] The hollow nanoparticles of the present invention are super hydrophobic materials, which have excellent hydrophobicity and can play a moisture-proof role, thereby improving the water resistance and service life of the thermal insulation composite fluorescent material.

[0012] Preferably, the method for preparing the hollow nanoparticles comprises the following steps: The template, the acrylate compound and the organosiloxane compound are mixed evenly, added to an acid solution, hydrolyzed, and the pH is adjusted to 9-11, and condensed to obtain a first precursor; Under an inert atmosphere, heating the first precursor to 60° C.-80° C., adding an initiator, and performing a copolymerization reaction to obtain a second precursor; The second precursor is heated to 300-500°C and calcined to obtain the hollow nanoparticles. More preferably, the template is α-methylstyrene.

[0013] More preferably, the mass ratio of the template to the acrylate compound is 1:0.25-1:4.

[0014] More preferably, the acrylate compound is at least one of isooctyl acrylate, tert-butyl acrylate or octadecyl acrylate.

[0015] More preferably, the organosiloxane compound is at least one of methyltriethoxysilane, phenyltriethoxysilane, ethyltriethoxysilane or tridecafluorooctyltriethoxysilane.

[0016] The ethoxy groups in the organic siloxane compound molecules used in the present invention can undergo a hydrolysis reaction to form silanol groups, which can then condense to form amphiphilic siloxane oligomers. The siloxane oligomers are composed of hydrophobic methyl and ethoxy groups and hydrophilic silanol groups, and can be anchored on the surface of the acrylate compound and the template as an emulsifier of the system, thereby reducing the surface free energy of the reaction system and dispersing the acrylate compound and the template monomer in the emulsion system. During the reaction, the siloxane oligomer shell formed by the condensation of the organic siloxane compound molecules will wrap the acrylate compound and the template monomer to form particles with a mesoporous structure. During the particle formation process, osmotic pressure will be generated due to the change in the monomer concentration inside and outside the shell; in addition, mechanical stirring during the reaction will also generate shear force. If the outer shell of the growing nanoparticles cannot withstand the osmotic pressure ( P ) and shear force ( F C ) will cause it to collapse at a vulnerable point, with part of the shell bending inward, forming a depression. Furthermore, the presence of mesopores in the siloxane oligomer shell generates a strong capillary force, which can transfer the acrylate compounds and template monomers inside the shell through the mesopores to the outside of the shell. Under the action of the initiator, copolymerization is initiated to form copolymer chains. At the same time, the amphiphilic siloxane oligomers remaining in the system continue to bind to the surface of the copolymer chains, reducing the system's surface energy and forming a protrusion structure on the particle surface, ultimately forming a multi-level hollow nanoparticle structure.

[0017] Further preferably, the mass ratio of the template to the acrylate compound is 1:0.25-1:4.

[0018] Further preferably, the mass ratio of the total mass of the template and the acrylate compound to the mass ratio of the organosiloxane compound is 1:0.25-1:4.

[0019] Further preferably, the ratio of the mass of the acid solution to the total mass of the template, the acrylate compound and the organosiloxane compound is 15:1-30:1; wherein the acid solution is a hydrochloric acid solution with a pH of 3-3.5.

[0020] More preferably, the initiator is at least one of potassium persulfate, ammonium persulfate, azobisisobutylamidine hydrochloride or azobisisobutylimidazoline hydrochloride.

[0021] Further preferably, the added amount of the initiator is 0.3%-1% of the total mass of the template and the acrylate compound.

[0022] More preferably, the hydrolysis reaction time is 1 h to 3 h.

[0023] More preferably, the condensation reaction time is 0.5h-2h.

[0024] More preferably, the copolymerization reaction time is 2h-5h.

[0025] More preferably, the calcination time is 3h-7h.

[0026] More preferably, the temperature is raised to 300° C.-500° C. in a programmed temperature rising manner, with a heating rate of 10° C. / min-20° C. / min.

[0027] Preferably, the heat stabilizer is at least one of a calcium zinc stabilizer or an organotin stabilizer.

[0028] More preferably, the heat stabilizer is a mixture of a calcium zinc stabilizer and an organotin stabilizer.

[0029] More preferably, the heat stabilizer is a calcium zinc stabilizer and an organic tin stabilizer in a mass ratio of 3:1-5:1.5.

[0030] The function of the heat stabilizer is to inhibit the degradation of the PVC resin and remove hydrogen chloride, while ensuring that the composite fluorescent material can maintain sufficient thermal stability, slowing down the degradation caused by photothermal effects, thereby extending the service life of the composite fluorescent material.

[0031] Preferably, the lubricant is calcium stearate and stearyl alcohol in a mass ratio of 1:0.5-1:2.

[0032] During the mixing process, lubricants primarily act as internal and external lubricants, reducing internal friction between polymer melt molecular chains and adhesion and friction between the melt and metal surfaces of the equipment, thereby effectively improving melt fluidity and processing stability. This not only facilitates uniform dispersion and complete melting of the material, but also reduces mechanical torque and equipment wear, lowers energy consumption, and prevents material retention and thermal degradation. Furthermore, in multi-component blends, lubricants help improve interfacial compatibility between components, promote dispersion, and enhance blend uniformity and final product performance.

[0033] The second aspect of the present invention provides a method for preparing the thermal insulation composite fluorescent material, comprising the following steps: weighing each raw material component according to the designed ratio, mixing at a speed of 5000rpm-10000rpm, then heating to 170℃-185℃ for blending, and compression molding to obtain the thermal insulation composite fluorescent material.

[0034] Preferably, the mixing time is 1 min to 3 min.

[0035] Preferably, the blending time is 3 min-7 min.

[0036] Preferably, the compression molding pressure is 10 MPa-20 MPa.

[0037] The preferred preparation method of the present invention can ensure the uniformity of the material, so that the material after melt blending can flow stably, with excellent molding effect, and ensure the mechanical properties of the thermal insulation composite fluorescent material. The preparation method provided by the present invention is simple to operate and can effectively reduce energy consumption during the processing process.

[0038] A third aspect of the present invention provides a use of the thermal insulation composite fluorescent material in the preparation of pipeline materials.

[0039] In summary, the present invention provides a thermal insulation composite fluorescent material with PVC resin and hollow nanoparticles as main raw materials. The hollow nanoparticles, as a new type of hollow structure filler, can not only significantly improve the thermal stability of PVC-based composite materials, but also give the composite materials excellent photoluminescence properties. In particular, in terms of thermal insulation and optical properties, hollow nanoparticles show better performance than traditional fillers. Based on their dual advantages in optics and thermal management, hollow nanoparticles give the thermal insulation composite fluorescent material excellent optical and thermal insulation properties. The pipeline material prepared using the thermal insulation composite fluorescent material not only has excellent thermal insulation performance, but can also monitor pipeline quality, providing a new design idea for the development of pipeline materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1Graph showing the hydrophobic effect of the hollow nanoparticles prepared in each embodiment; Figure 2 The following are scanning electron micrographs and transmission electron micrographs of the hollow nanoparticles prepared in each embodiment; Figures a and b are scanning electron micrographs of the hollow nanoparticles at different magnifications; Figures c and d are transmission electron micrographs of the hollow nanoparticles at the same magnification; Figure 3 Infrared spectra of the composite material prepared in Comparative Example 1, the thermal insulation composite fluorescent material prepared in Example 1, the thermal insulation composite fluorescent material prepared in Example 4, and the hollow nanoparticles prepared in each example; Figure 4 Thermal conductivity test graphs of the composite materials prepared in Comparative Examples 1-3, the thermal insulation composite fluorescent material prepared in Example 1, and the thermal insulation composite fluorescent material prepared in Example 4; Figure 5 Graphs showing thermal insulation performance tests of the composite materials prepared in Comparative Examples 1-3, the thermal insulation composite fluorescent material prepared in Example 1, and the thermal insulation composite fluorescent material prepared in Example 4; Figure 6 The fluorescence emission spectra of the composite material prepared in Comparative Example 1, the thermal insulation composite fluorescent materials prepared in Examples 1-5, and the hollow nanoparticles obtained in each example; Figure 7 Fluorescence photos of the hollow nanoparticles obtained in each example under 365nm ultraviolet light; Figure 8 These are fluorescence photographs of the composite material obtained in Comparative Example 1 and the thermal insulation composite fluorescent materials prepared in Examples 1-5 under 365nm ultraviolet light irradiation. DETAILED DESCRIPTION

[0041] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0042] Example 1 This embodiment provides a thermal insulation composite fluorescent material PVC / ASOA2, which specifically includes the following contents: the thermal insulation composite fluorescent material includes the following raw material components in parts by mass: 100 parts of PVC resin, 2 parts of hollow nanoparticles, 2 parts of organic tin stabilizer and 1 part of lubricant; wherein, the hollow nanoparticles include hollow silica core balls and hollow silica spheres attached to the surface thereof; the lubricant is calcium stearate and octadecyl alcohol in a mass ratio of 1:1.

[0043] The preparation method of the thermal insulation composite fluorescent material comprises the following steps: The raw material components were weighed according to the designed ratio, mixed at a speed of 8000 rpm for 3 minutes, heated to 178° C. for melt blending for 5 minutes, and then compression molded at a pressure of 18 MPa to obtain a thermal insulation composite fluorescent material.

[0044] The preparation method of the hollow nanoparticles comprises the following steps: 0.96 g of α-methylstyrene, 0.24 g of isooctyl acrylate, and 1.2 g of methyltriethoxysilane were ultrasonically dispersed at 40 Hz for 5 minutes and mixed uniformly to obtain a mixture; the mixture was dropwise added to a hydrochloric acid aqueous solution with a pH of 3.5 at an injection rate of 0.4 g / min to carry out a hydrolysis reaction for 1 hour; then, 28% ammonia water was added to adjust the pH of the system to 10, and a condensation reaction was carried out for 50 minutes to obtain a first precursor; Under an inert atmosphere, the first precursor was heated to 70° C., 0.008 g of potassium persulfate was added, and copolymerization reaction was carried out for 2 h, followed by freeze-drying to obtain a second precursor; The second precursor was heated to 500° C. at a heating rate of 10° C. / min and calcined for 4 hours to obtain the hollow nanoparticles.

[0045] It was determined that the water contact angle of the hollow nanoparticles was 157°, the diameter was 550 nm, and the diameter of the hollow silica core sphere was 250 nm.

[0046] Example 2 This embodiment provides a thermal insulation composite fluorescent material PVC / ASOA4, which specifically includes the following contents: the thermal insulation composite fluorescent material includes the following raw material components in parts by mass: 100 parts of PVC resin, 4 parts of hollow nanoparticles, 2 parts of organic tin stabilizer and 1 part of lubricant; wherein, the hollow nanoparticles include hollow silica core balls and hollow silica spheres attached to the surface thereof; the lubricant is calcium stearate and octadecyl alcohol in a mass ratio of 1:2.

[0047] The preparation method of the thermal insulation composite fluorescent material comprises the following steps: The raw material components were weighed according to the designed ratio, mixed at a speed of 10,000 rpm for 2 minutes, heated to 180° C. for melt blending for 5 minutes, and then compression molded at a pressure of 15 MPa to obtain a thermal insulation composite fluorescent material.

[0048] The preparation method of the hollow nanoparticles comprises the following steps: 0.96 g of α-methylstyrene, 0.24 g of isooctyl acrylate, and 1.2 g of methyltriethoxysilane were ultrasonically dispersed at 40 Hz for 5 minutes and mixed uniformly to obtain a mixture; the mixture was dropwise added to a hydrochloric acid aqueous solution with a pH of 3.5 at an injection rate of 0.4 g / min to carry out a hydrolysis reaction for 1 hour; then, 28% ammonia water was added to adjust the pH of the system to 10, and a condensation reaction was carried out for 50 minutes to obtain a first precursor; Under an inert atmosphere, the first precursor was heated to 70° C., 0.008 g of potassium persulfate was added, and copolymerization reaction was carried out for 2 h, followed by freeze-drying to obtain a second precursor; The second precursor was heated to 500° C. at a heating rate of 10° C. / min and calcined for 4 hours to obtain the hollow nanoparticles.

[0049] It was determined that the water contact angle of the hollow nanoparticles was 157°, the diameter was 550 nm, and the diameter of the hollow silica core sphere was 250 nm.

[0050] Example 3 This embodiment provides a thermal insulation composite fluorescent material PVC / ASOA6, which specifically includes the following contents: the thermal insulation composite fluorescent material includes the following raw material components in parts by mass: 100 parts of PVC resin, 6 parts of hollow nanoparticles, 2 parts of calcium zinc stabilizer and 1 part of lubricant; wherein, the hollow nanoparticles include hollow silica core balls and hollow silica spheres attached to the surface thereof; the lubricant is calcium stearate and octadecyl alcohol in a mass ratio of 1:1.5.

[0051] The preparation method of the thermal insulation composite fluorescent material comprises the following steps: The raw material components were weighed according to the designed ratio, mixed at a speed of 9000 rpm for 3 minutes, heated to 175° C. for melt blending for 7 minutes, and then compression molded at a pressure of 20 MPa to obtain a thermal insulation composite fluorescent material.

[0052] The preparation method of the hollow nanoparticles comprises the following steps: 0.96 g of α-methylstyrene, 0.24 g of isooctyl acrylate, and 1.2 g of methyltriethoxysilane were ultrasonically dispersed at 40 Hz for 5 minutes and mixed uniformly to obtain a mixture; the mixture was dropwise added to a hydrochloric acid aqueous solution with a pH of 3.5 at an injection rate of 0.4 g / min to carry out a hydrolysis reaction for 1 hour; then, 28% ammonia water was added to adjust the pH of the system to 10, and a condensation reaction was carried out for 50 minutes to obtain a first precursor; Under an inert atmosphere, the first precursor was heated to 70° C., 0.008 g of potassium persulfate was added, and copolymerization reaction was carried out for 2 h, followed by freeze-drying to obtain a second precursor; The second precursor was heated to 500° C. at a heating rate of 10° C. / min and calcined for 4 hours to obtain the hollow nanoparticles.

[0053] It was determined that the water contact angle of the hollow nanoparticles was 157°, the diameter was 550 nm, and the diameter of the hollow silica core sphere was 250 nm.

[0054] Example 4 This embodiment provides a thermal insulation composite fluorescent material PVC / ASOA8, which specifically includes the following contents: the thermal insulation composite fluorescent material includes the following raw material components in parts by mass: 100 parts of PVC resin, 8 parts of hollow nanoparticles, 2 parts of heat stabilizer and 1 part of lubricant; wherein, the hollow nanoparticles include hollow silica core balls and hollow silica balls attached to the surface thereof; the heat stabilizer is a calcium zinc stabilizer and an organic tin stabilizer in a mass ratio of 3:1.8; the lubricant is calcium stearate and octadecyl alcohol in a mass ratio of 1:0.8.

[0055] The preparation method of the thermal insulation composite fluorescent material comprises the following steps: The raw material components were weighed according to the designed ratio, mixed at a speed of 8000 rpm for 2 minutes, heated to 182° C. for melt blending for 5 minutes, and then compression molded at a pressure of 20 MPa to obtain a thermal insulation composite fluorescent material.

[0056] The preparation method of the hollow nanoparticles comprises the following steps: 0.96 g of α-methylstyrene, 0.24 g of isooctyl acrylate, and 1.2 g of methyltriethoxysilane were ultrasonically dispersed at 40 Hz for 5 minutes and mixed uniformly to obtain a mixture; the mixture was dropwise added to a hydrochloric acid aqueous solution with a pH of 3.5 at an injection rate of 0.4 g / min to carry out a hydrolysis reaction for 1 hour; then, 28% ammonia water was added to adjust the pH of the system to 10, and a condensation reaction was carried out for 50 minutes to obtain a first precursor; Under an inert atmosphere, the first precursor was heated to 70° C., 0.008 g of potassium persulfate was added, and copolymerization reaction was carried out for 2 h, followed by freeze-drying to obtain a second precursor; The second precursor was heated to 500° C. at a heating rate of 10° C. / min and calcined for 4 hours to obtain the hollow nanoparticles.

[0057] It was determined that the water contact angle of the hollow nanoparticles was 157°, the diameter was 550 nm, and the diameter of the hollow silica core sphere was 250 nm.

[0058] Example 5 This embodiment provides a thermal insulation composite fluorescent material PVC / ASOA 10, specifically including the following contents: the thermal insulation composite fluorescent material includes the following raw material components in parts by mass: 100 parts of PVC resin, 10 parts of hollow nanoparticles, 2 parts of organic tin stabilizer and 1 part of lubricant; wherein, the hollow nanoparticles include hollow silica core balls and hollow silica balls attached to their surfaces; the lubricant is calcium stearate and octadecyl alcohol in a mass ratio of 1:1.2.

[0059] The preparation method of the thermal insulation composite fluorescent material comprises the following steps: The raw material components were weighed according to the designed ratio, mixed at a speed of 10,000 rpm for 3 minutes, heated to 185° C. for melt blending for 5 minutes, and then compression molded at a pressure of 20 MPa to obtain a thermal insulation composite fluorescent material.

[0060] The preparation method of the hollow nanoparticles comprises the following steps: 0.96 g of α-methylstyrene, 0.24 g of isooctyl acrylate, and 1.2 g of methyltriethoxysilane were ultrasonically dispersed at 40 Hz for 5 minutes and mixed uniformly to obtain a mixture; the mixture was dropwise added to a hydrochloric acid aqueous solution with a pH of 3.5 at an injection rate of 0.4 g / min to carry out a hydrolysis reaction for 1 hour; then, 28% ammonia water was added to adjust the pH of the system to 10, and a condensation reaction was carried out for 50 minutes to obtain a first precursor; Under an inert atmosphere, the first precursor was heated to 70° C., 0.008 g of potassium persulfate was added, and copolymerization reaction was carried out for 2 h, followed by freeze-drying to obtain a second precursor; The second precursor was heated to 500° C. at a heating rate of 10° C. / min and calcined for 4 hours to obtain the hollow nanoparticles.

[0061] It was determined that the water contact angle of the hollow nanoparticles was 157°, the diameter was 550 nm, and the diameter of the hollow silica core sphere was 250 nm.

[0062] Comparative Example 1 This comparative example provides a composite material PVC / ASOA0, which differs from Example 1 in that it does not contain hollow nanoparticles. Other components and preparation processes are consistent with Example 1 and are not described here.

[0063] Comparative Example 2 This comparative example provides a composite material PVC / SiO 2-2 The difference from Example 1 is that the hollow nanoparticles are replaced by an equal amount of solid silica spheres with a particle size of 550 nm. The other components and preparation process are consistent with those of Example 1 and are not described here.

[0064] Comparative Example 3 This comparative example provides a composite material PVC / SiO 2-8 The difference from Example 4 is that the hollow nanoparticles are replaced with an equal amount of solid silica spheres, and the other components and preparation process are consistent with those of Example 1 and will not be repeated here.

[0065] In order to further confirm the technical effect of the present invention, the present invention conducted the following tests: The present invention conducted a hydrophobicity test on the hollow nanoparticles obtained in each embodiment: the hollow nanoparticles were dispersed in an ethanol solution to obtain a dispersion; the dispersion was dropwise applied to a clean glass slide and dried at 50°C for 8 hours to obtain a particle film; the contact angle of water droplets at different positions on the particle film surface was measured using a contact angle tester model DSA30S from Krüss, Germany, and the average value was taken. Figure 1 shown.

[0066] The present invention also used a Japanese 7610F scanning electron microscope and an American Talos F200S transmission electron microscope to perform scanning electron microscopy and transmission electron microscopy tests on the hollow nanoparticles obtained in each embodiment. The results are as follows: Figure 2 As shown, according to Figure 2 It can be seen that the hollow nanoparticles are a multi-level bowl-shaped hollow structure, including a hollow core and a ball-on-ball bowl-shaped hollow shell, presenting a multi-level morphology; such a morphology can, on the one hand, enhance the mechanical strength of the PVC material, and on the other hand, can uniformly adsorb and disperse the additives, thereby enhancing the compatibility of the PVC resin and the additives.

[0067] The hollow nanoparticles obtained in Comparative Example 1, Example 1, Example 4 and each example were tested by Fourier transform infrared spectroscopy using a German Tensor-27 spectrometer. The results are as follows: Figure 3 As shown. At 1126cm -1 、1037cm -1 and 437cm -1 The stretching and bending vibration absorption bands of Si-O-Si (Si-OH) bonds are shown at 1270 cm -1 and 777cm -1 The stretching and bending vibration absorption bands of Si-CH3 bond are shown at 1600 cm -1 、1490cm -1 、1494cm -1 、1450cm -1 and 698cm -1 The characteristic absorption band of benzene ring is shown at 1730 cm -1 The characteristic absorption band of stretching vibration of C=O bond is shown, which indicates that the thermal insulation composite fluorescent material has been successfully prepared.

[0068] The present invention tests the thermal conductivity of the thermal insulation composite fluorescent material prepared in Example 1, the thermal insulation composite fluorescent material prepared in Example 4, and the composite materials prepared in the comparative examples. The results are shown in Tables 1 and Figure 4 shown.

[0069] Table 1 Thermal conductivity test results of the composite materials obtained in Example 1, Example 4 and comparative examples

[0070] According to Table 1 and Figure 4 As can be seen, with increasing addition levels of the processing aid ASOA nano-bowl-shaped hollow particles, the hollow bowl-shaped structure imparts a larger specific surface area and internal cavity to the ASOA particles (hollow nanoparticles). This effectively forms a thermal barrier within the composite material, slowing heat transfer and limiting the diffusion of thermal decomposition products. This significantly enhances the thermal insulation properties of the PVC composite. Compared to the thermal conductivity of 0.1473 W / m*K for pure PVC composite resin in Comparative Example 1, the thermal conductivity of the PVC / ASOA8 composite in Example 4 is reduced to 0.0617 W / m*K, demonstrating significantly enhanced thermal insulation performance. The P value is <0.05, indicating a significant difference.

[0071] In order to further evaluate the thermal insulation performance of the composite material, the present invention placed the thermal insulation composite fluorescent material obtained in Example 1, the thermal insulation composite fluorescent material obtained in Example 4, and the composite materials obtained in Comparative Examples 1-3 on a heating platform at a temperature of 120°C. During the heating process, an infrared thermal imager was used to monitor the changes in the surface temperature of the coating in real time. The purpose was to evaluate the thermal insulation effect by comparing the temperature rise rate of different samples during the heating process. The results are as follows: Figure 5 As shown. Figure 5 It can be seen that hollow nanoparticles perform significantly better than SiO2 nanoparticles in terms of thermal insulation performance. Under the same heating conditions, the temperature rise of the PVC / ASOA composite material is significantly lower than that of the PVC / SiO2 composite material. This phenomenon shows that hollow nanoparticles as fillers can effectively inhibit heat transfer, thereby significantly improving the thermal insulation capacity of the composite material. It is particularly noteworthy that with the increase of hollow nanoparticle content, the thermal insulation effect of the PVC composite material gradually increases. Within the same heating time, the PVC / ASOA8 composite material with a higher hollow nanoparticle content exhibits the slowest temperature rise rate, indicating that the addition of hollow nanoparticles to the composite material can effectively prevent heat transfer, and as their content increases, the thermal resistance of the material is further enhanced. The excellent thermal insulation performance of the PVC composite resin is closely related to the hollow bowl-shaped structure of the hollow nanoparticles. This structure effectively increases the gas voids, thereby destroying the continuity of the heat conduction path and improving the thermal insulation performance of the material.

[0072] Furthermore, while SiO2 particles offer some thermal barrier properties, their dense structure reduces their ability to inhibit heat conduction. However, they offer significant advantages in improving the thermal insulation properties of PVC composites. Compared to traditional SiO2 nanoparticles, hollow nanoparticles demonstrate superior performance in reducing thermal conductivity and enhancing the thermal insulation performance of materials. This property holds great promise for hollow nanoparticles in thermal management, building insulation, and other high-performance thermal insulation applications.

[0073] The present invention also uses the British FSP920 fluorescence spectrometer to measure the fluorescence intensity of the composite material prepared in Comparative Example 1, the thermal insulation composite fluorescent material prepared in Examples 1-5, and the hollow nanoparticles obtained in each example. The results are as follows: Figure 6 As shown in the figure, with the increase of the amount of hollow nanoparticles added as the additive, the fluorescence intensity of the PVC composite material is significantly enhanced, which shows that the addition of hollow nanoparticles makes the PVC composite material have the characteristics of photoluminescence.

[0074] The present invention also conducted fluorescence tests on the composite material obtained in Comparative Example 1 and the thermal insulation composite fluorescent materials and hollow nanoparticles obtained in each embodiment. The results are as follows: Figure 7-8 As shown. Figure 7 It can be seen that under 365nm ultraviolet radiation, the hollow nanoparticle powder exhibits strong blue fluorescence, a property closely related to its hollow bowl-shaped structure. The research results show that hollow nanoparticles can effectively absorb ultraviolet light and emit visible light under the excitation of short-wave radiation, giving them significant photoluminescence properties. In particular, the structural defects of the hollow nanoparticle morphology significantly enhance the fluorescence of the composite material.

[0075] After adding hollow nanoparticles into PVC resin, the thermal insulation composite fluorescent material prepared also exhibited photoluminescence properties. Under ultraviolet light irradiation, the thermal insulation composite fluorescent material exhibited bright blue fluorescence, proving that the fluorescent properties of the hollow nanoparticles in the composite material were effectively retained. This shows that the hollow nanoparticles can not only exhibit fluorescent properties in powder form, but also maintain their luminescence ability after being blended with PVC to form a composite material. In contrast, Comparative Example 1, in which no hollow nanoparticles were added, did not show any fluorescence phenomenon under the same ultraviolet irradiation, which further verified the key role of hollow nanoparticles in giving the composite material photoluminescence properties. This result shows that the hollow nanoparticles provided by the present invention can not only enhance the thermal stability of the composite material, but also give the material unique fluorescent properties, which is of great significance for application fields requiring specific optical properties.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A thermal insulation composite fluorescent material, characterized by: The invention comprises the following raw material components in parts by weight: 90-110 parts of PVC resin, 2-10 parts of hollow nanoparticles, 1.5-5 parts of heat stabilizer and 0.8-1.2 parts of lubricant; wherein the hollow nanoparticles comprise hollow silica core balls and hollow silica spheres attached to the surface of the hollow nanoparticles.

2. The thermal insulation composite fluorescent material according to claim 1, characterized in that: The diameter of the hollow silica core sphere is 200nm-400nm; and / or The diameter of the hollow silica spheres is 100 nm to 200 nm; and / or The water contact angle of the hollow nanoparticles is 150°-160°.

3. The thermal insulation composite fluorescent material according to claim 1 or 2, characterized in that: The preparation method of the hollow nanoparticles comprises the following steps: The template, the acrylate compound and the organosiloxane compound are mixed evenly, added to an acid solution, hydrolyzed, and the pH is adjusted to 9-11, and condensed to obtain a first precursor; Under an inert atmosphere, heating the first precursor to 60° C.-80° C., adding an initiator, and performing a copolymerization reaction to obtain a second precursor; The second precursor is heated to 300° C.-500° C. and calcined to obtain the hollow nanoparticles.

4. The thermal insulation composite fluorescent material according to claim 3, characterized in that: The template is α-methylstyrene.

5. The thermal insulation composite fluorescent material according to claim 3 or 4, characterized in that: The mass ratio of the template to the acrylate compound is 1:0.25-1:4; and / or The mass ratio of the total amount of the template and the acrylate compound to the organosiloxane compound is 1:0.25-1:4; and / or The mass ratio of the acid solution to the total amount of the template, the acrylate compound and the organosiloxane compound is 15:1-30:1; wherein the acid solution is a hydrochloric acid solution with a pH of 3-3.

5.

6. The thermal insulation composite fluorescent material according to claim 3, characterized in that: The initiator is at least one of potassium persulfate, ammonium persulfate, azobisisobutylamidine hydrochloride or azobisisobutylimidazoline hydrochloride; and / or The amount of the initiator added is 0.3%-1% of the total mass of the template and the acrylate compound.

7. The thermal insulation composite fluorescent material according to claim 3, wherein: The hydrolysis reaction time is 1h-3h; and / or The condensation reaction time is 0.5h-2h; and / or The copolymerization reaction time is 2h-5h; and / or The calcination time is 3h-7h; and / or The temperature is raised to 300°C-500°C by programmed temperature increase at a rate of 10°C / min-20°C / min.

8. The thermal insulation composite fluorescent material according to claim 1, wherein: The heat stabilizer is at least one of a calcium zinc stabilizer or an organic tin stabilizer; and / or The lubricant is calcium stearate and octadecyl alcohol in a mass ratio of 1:0.5-1:

2.

9. A method for preparing the thermal insulation composite fluorescent material according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: weighing various raw material components according to the designed ratio, mixing them at a rotation speed of 5000-10000 rpm, heating them to 170-185° C. for blending, and performing compression molding to obtain a thermal insulation composite fluorescent material.

10. Use of the thermal insulation composite fluorescent material according to any one of claims 1 to 8 in the preparation of pipeline materials.

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