Multifunctional nano-composite organogel strain sensor and preparation method and application thereof
By preparing multifunctional nanocomposite organic gel strain sensors, the problems of single function and insufficient lubricity of seals in traditional laparoscopic puncture devices are solved, real-time monitoring and lubricity are achieved, ensuring surgical safety and operation convenience.
Patent Information
- Application Number
- CN202510396360.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-31
- Publication Date
- 2025-07-04
AI Technical Summary
The seals of traditional laparoscopic puncture devices have a single function, lack real-time monitoring performance, and cannot assist surgeons in precise control of the insertion and removal of the device. There is a risk of operational errors, and there is a long-term lack of lubricity.
A multifunctional nanocomposite organic gel strain sensor is adopted to form an interpenetrating network structure through polyvinyl alcohol and acrylic acid. Nanosilicon dioxide enhances tear resistance, lithium chloride provides conductive ions, combined with glycerol and polyether modified silicone oil treatment, enhances lubricity and corrosion resistance, and installs wires to form sensors.
Real-time monitoring of puncture needle operation during surgery is achieved to ensure smooth operation, with high toughness, tear resistance, fatigue resistance, self-recovery, long-lasting lubricity and airtightness, providing reliable sensing performance and reducing the risk of operating errors.
Smart Images
Figure CN120252492A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical fields of flexible strain sensors and polymer organic gels, and relates to a multifunctional nano-composite organic gel strain sensor, a preparation method thereof, and an application thereof. Background Art
[0002] Laparoscopic surgery, as a model of modern minimally invasive surgical techniques, has been widely promoted and applied in the field of surgical medicine due to its advantages of small trauma, rapid recovery, few complications, and good aesthetics. Laparoscopic surgery uses trocars to create several small incisions in the abdomen and introduces surgical tools (such as laparoscopes, grasping forceps, and electrosurgical instruments, etc.) into the target area in the abdominal cavity through trocar sheaths for surgical operations. Among them, the seal (usually 25 mm in diameter with a hole about 2.5 mm in diameter) is a key component of the laparoscopic trocar and plays an important role in maintaining the stability of the pneumoperitoneum pressure during the surgical process, providing sufficient operating and observation space for surgeons. However, there is still room for improvement in the safety and operational convenience of the trocar seal in laparoscopic surgery. Traditional seals only have a single sealing function and lack the performance of real-time monitoring during the surgical operation, and cannot assist surgeons in accurately controlling the insertion and extraction force of the instruments, which may increase the risk of operation errors, and further cause damage to soft tissues (peritoneal structures, muscle fascia, blood vessels, nerves, fat, etc.) or organs (stomach, intestine, liver, gallbladder, pancreas, kidney, spleen, etc.) in the abdominal cavity, and even endanger the life of the patient. In view of this, it is of great significance to develop a multifunctional nano-composite organic hydrogel with excellent mechanical properties (including high toughness, high tear resistance, high puncture resistance, high fatigue resistance, rapid self-recovery), durable airtightness, durable self-lubrication, high corrosion resistance, excellent biocompatibility, and sensing performance for constructing an intelligent laparoscopic trocar seal system and realizing real-time monitoring during the surgical process.
[0003] In recent years, ion-conductive organic hydrogels have emerged as a highly regarded flexible functional material due to their flexible functional design and excellent environmental stability, and are widely used in fields such as health diagnosis, biosensing, and intelligent medical devices. However, traditional organic hydrogels face severe challenges in balancing multifunctionality. Especially when designing a trocar seal with a central hole, how to overcome the complex trade-offs between functions has become a key problem restricting the development of the next-generation flexible sensors in the intelligent laparoscopic trocar seal system. The multifunctional organic hydrogels applicable to laparoscopic surgery need to meet the following key requirements: (1) Have high strength and high toughness to resist repeated external forces; (2) Demonstrate excellent fatigue resistance and self-recovery performance to ensure that they can withstand the repeated insertion and removal of instruments during surgery without failure; (3) Provide excellent airtightness to maintain the pneumoperitoneum environment and ensure the smooth progress of the surgery; (4) Exhibit high sensitivity and long-term stability to provide reliable guarantee for long-term surgical monitoring. Therefore, exploring new types of nanocomposite organic hydrogel strain sensors, optimizing their comprehensive performance, and meeting the special requirements of the intelligent laparoscopic trocar seal system have become the focus and difficulty of current research. Summary of the Invention
[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a multifunctional nanocomposite organic gel strain sensor, its preparation method and application. The strain sensing material simultaneously has a variety of excellent comprehensive properties, including mechanical properties (high toughness, high tear resistance, high puncture resistance, high fatigue resistance, rapid self-recovery), persistent airtightness, persistent lubricity, high corrosion resistance, excellent biocompatibility and sensing performance. As the core component of the intelligent seal system in laparoscopic surgery, this multifunctional nanocomposite organic gel can not only maintain the sealed state during surgery and maintain the pneumoperitoneum pressure required for surgery, but also act as a strain sensor to real-time monitor the cyclic repeated insertion and removal operations of the trocar needle, showing distinguishable electrical signals and continuous stability during the cyclic insertion and removal of the trocar needle, real-time monitoring the operation accuracy of the surgeon during surgery, ensuring the smooth progress of the surgery, thus realizing the combination of the real-time monitoring system and intelligent medical devices, and effectively solving the technical problems of the single function of traditional trocar seals, lack of real-time monitoring function and insufficient long-term lubricity in the prior art.
[0005] The present invention is realized through the following technical solutions: A preparation method of a multifunctional nanocomposite organic gel strain sensor, comprising the following steps: S1: Mix acrylic acid, nano-silica, and a photoinitiator evenly to obtain a mixed suspension; then mix a polyvinyl alcohol solution, lithium chloride, and the mixed suspension evenly to obtain a nanocomposite hydrogel precursor solution; S2: After allowing the nano-composite hydrogel precursor solution to stand under vacuum, initiate a polymerization reaction under ultraviolet light to obtain a nano-composite hydrogel; S3: Immerse the nano-composite hydrogel in glycerol and then in polyether-modified silicone oil to obtain a nano-composite organic gel; S4: Shape the nano-composite organic gel and install a wire on the shaped nano-composite organic gel to obtain the multifunctional nano-composite organic gel strain sensor.
[0006] Preferably, the size of the nano-silica is 30 - 60 nm.
[0007] Preferably, the mass ratio of polyvinyl alcohol to acrylic acid is 1:(9 - 3).
[0008] Preferably, the nano-silica accounts for 0.5% - 4% of the total mass of acrylic acid, nano-silica, photoinitiator, polyvinyl alcohol solution, and lithium chloride.
[0009] Preferably, the concentration of lithium chloride is 3 mol / L.
[0010] Preferably, in step S2, the time for allowing the nano-composite hydrogel precursor solution to stand under vacuum is 20 - 30 min.
[0011] Preferably, in step S2, when irradiated with ultraviolet light, the wavelength is 365 nm and the time is 10 - 15 h.
[0012] Preferably, in step S3, the time for immersing the nano-composite hydrogel in glycerol is 4 - 6 h; the time for immersing in polyether-modified silicone oil is 4 - 6 h.
[0013] A multifunctional nano-composite organic gel strain sensor is obtained by the above method; the fracture strength of the multifunctional nano-composite organic gel strain sensor is 1.78 - 3.31 MPa, and the toughness is 4.22 - 6.43 MJ / m 3 ; The Young's modulus of the multifunctional nano-composite organic gel strain sensor is 0.23 - 0.64 MPa, and the time for the multifunctional nano-composite organic gel strain sensor to recover 90% at 60% strain is 500 - 600 s; The friction coefficient of the multifunctional nano-composite organic gel strain sensor is 0.1 - 0.2; The sensitivity of the multifunctional nano-composite organic gel strain sensor is 0.9 - 2.
[0014] Application of the above-mentioned multifunctional nano-composite organic gel strain sensor as a seal for laparoscopic trocars.
[0015] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention discloses a preparation method of a multifunctional nano-composite organic gel strain sensor. Firstly, polyvinyl alcohol is dissolved in water to form a physically cross-linked hydrogen bond network, providing the basic framework structure of the hydrogel. Acrylic acid forms a cross-linked polyacrylic acid network through photoinitiated polymerization by a subsequent photoinitiator. Moreover, polyvinyl alcohol and polyacrylic acid form an interpenetrating network structure through the physical cross-linking network, enhancing the mechanical properties of the hydrogel. Nano-silica is dispersed in the hydrogel matrix, enhancing the tear resistance of the material and preventing structural damage caused by repeated deformation. In addition, the silica nanoparticles act as nano-crosslinking agents, and a large number of physical cross-linking points are formed in the polymer network through hydrogen bonds between the hydroxyl groups on their surfaces and the carboxyl groups on the polyacrylic acid polymer chains, effectively improving the mechanical properties, tear resistance, and puncture resistance of the gel. At the same time, the added lithium chloride provides conductive ions, enhancing the ionic conductivity of the final gel.
[0016] Secondly, during the preparation process of this method, acrylic acid monomers, nano-silica, and photoinitiator are first mixed to obtain silica@polyacrylic acid nanoparticles (SiO2@PAA NPs) coated with polyacrylic acid, effectively improving the dispersion uniformity of nano-silica in the gel and significantly enhancing the comprehensive mechanical properties of the nano-composite organic gel. In addition, during the solvent replacement process of the hydrogel, the water in the hydrogel is gradually replaced in glycerol first, effectively realizing the water retention function of the gel, avoiding drying and cracking caused by water evaporation during use and mechanical degradation. Then, it is soaked and treated in polyether-modified silicone oil, effectively improving the lubrication performance of the gel, reducing the friction during use, and simultaneously reducing the physical damage to the gel. Through the soaking and replacement treatment in glycerol and polyether-modified silicone oil, the composite hydrogel is transformed into a composite organic gel, enhancing the corrosion resistance, environmental stability, and durability of the gel.
[0017] Thirdly, the nano-composite organic gel prepared in the present invention is shaped and assembled with wires to form a strain sensor. The sensing mechanism of this strain sensor is as follows: during the stretching process, the resistance (R = ρL / S) of the nano-composite organic hydrogel increases significantly with the increase of strain (λ). This is because the resistivity (ρ) is a constant value, while the conductivity gradually decreases as the cross-sectional area (S) of the material decreases and the extended length (L) increases. Therefore, when an external force is applied, the internal conduction path of the organic hydrogel changes or rearranges, resulting in an increase in resistance. Thanks to the self-recovery behavior of the organic hydrogel, once the strain is released, the conductive path in the polymer network of the nano-composite organic hydrogel can quickly recover, thus realizing a decrease in resistance and achieving real-time monitoring of the strain process.
[0018] The multifunctional nano-composite organic gel strain sensor of the present invention has high toughness, exhibits excellent energy dissipation performance under external forces, has high tear resistance, high puncture resistance, high fatigue resistance and rapid self-recovery, and can withstand repeated insertion and extraction operations during long-term laparoscopic surgery; at the same time, the multifunctional nano-composite organic gel strain sensor has persistent self-lubricity and airtightness, maintaining the pneumoperitoneum pressure required during the operation to ensure the smooth progress of the operation; moreover, the new intelligent trocar sealing system constructed based on the multifunctional nano-composite organic gel strain sensor can, during long-term laparoscopic surgery, real-time monitor the repeated insertion and extraction operations of the trocar needle, show distinguishable electrical signals and continuous electrical signal stability during the cyclic insertion and extraction of the trocar needle, real-time monitor the operation accuracy of the surgeon during the operation, ensure the smooth progress of the operation, thus realizing the combination of the real-time monitoring system and intelligent medical devices, and effectively solving the technical problems of the traditional trocar seal in the prior art having a single function, lacking a real-time monitoring function and insufficient long-term lubricity. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.
[0020] Figure 1 is a schematic diagram of the multifunctional nano-composite organic gel described in Embodiments 1-4; Figure 2 is a stress-strain diagram of the multifunctional nano-composite organic gel described in Embodiment 3; Figure 3 is a stress-strain diagram of the multifunctional nano-composite organic gel described in Embodiment 3 under loading-unloading at different rest times; Figure 4 is a stress-fracture elongation diagram of the multifunctional nano-composite organic gel described in Embodiment 3; Figure 5 is a schematic diagram of the puncture resistance of the multifunctional nano-composite organic gel described in Embodiment 3; Figure 6 is a puncture force-puncture distance curve graph of the multifunctional nano-composite organic gel described in Embodiment 3; Figure 7 is a schematic diagram of the insertion of the multifunctional nano-composite organic gel described in Embodiment 3; Figure 8It is a bar chart of the maximum insertion force and extraction force of the multifunctional nano-composite organic gel described in Example 3 during the cyclic insertion-extraction process; Figure 9 It is the friction coefficient of the multifunctional nano-composite organic gel described in Example 3 and traditional sealant materials under different pressures; Figure 10 It is the water retention test result of the multifunctional nano-composite organic gel described in Example 3 at 25 °C; Figure 11 It is the corrosion test of the nano-composite organic gel on surgical instruments; Figure 12 It is the airtightness schematic diagram of the multifunctional nano-composite organic gel described in Example 3; Figure 13 It is the resistance change diagram of the multifunctional nano-composite organic gel sensor described in Example 3 under tension; Figure 14 It is the relationship curve diagram of the resistance of the multifunctional nano-composite organic gel sensor described in Example 3 relative to time under different strains; Figure 15 It is the relationship curve diagram of the resistance of the multifunctional nano-composite organic gel sensor described in Example 3 relative to time during the cyclic insertion and extraction process; Figure 16 It is the schematic diagram of the multifunctional nano-composite organic gel sensor described in Example 3 simulating the laparoscopic surgery operation process. Detailed implementation manners
[0021] To enable those skilled in the art to understand the features and effects of the present invention, the following provides a general description and definition of the terms and phrases mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used herein shall have the ordinary meaning understood by those skilled in the art for the present invention. In case of conflict, the definition in this specification shall prevail.
[0022] The theories or mechanisms described and disclosed herein, whether correct or incorrect, shall not limit the scope of the present invention in any way, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism.
[0023] In this article, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are only for the sake of brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be regarded as having covered and specifically disclosed all possible sub-ranges and individual numerical values (including integers and fractions) within the range.
[0024] In this text, unless otherwise specified, the terms "comprise", "include", "contain", "have" or similar terms cover the meanings of "consist of" and "consist essentially of". For example, "A comprises a" covers the meanings of "A comprises a and others" and "A consists only of a".
[0025] In this text, for the sake of brevity of description, not all possible combinations of all technical features in each embodiment or example are described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered to be within the scope described in this specification.
[0026] As Figure 1 shown, the present invention provides a method for preparing a multifunctional nano - composite organic gel strain sensor, comprising the following steps: S1: After mixing acrylic acid, nano - silica and a photo - initiator uniformly, a mixed suspension is prepared, that is Then, after mixing a polyvinyl alcohol solution, lithium chloride and the above - mentioned mixed suspension uniformly, a nano - composite hydrogel precursor solution is prepared; Specifically, in the above process, after mixing acrylic acid, nano - silica and a photo - initiator, stir at 60 °C for 10 min to prepare the above - mentioned mixed suspension; The preparation process of the above - mentioned polyvinyl alcohol solution is to disperse polyvinyl alcohol in water and stir evenly to prepare the polyvinyl alcohol solution; In addition, the size of the above - mentioned nano - silica is 30 - 60 nm, preferably 30 nm; The mass ratio of the polyvinyl alcohol to acrylic acid is 1:(9 - 3), preferably 1:9; The nano - silica accounts for 0.5% - 4% of the total mass of acrylic acid, nano - silica, photo - initiator, polyvinyl alcohol solution and lithium chloride, preferably 3%; The concentration of the lithium chloride is 3 mol / L.
[0027] S2: After standing the nano - composite hydrogel precursor solution under vacuum for 20 - 30 min, carry out a polymerization reaction under ultraviolet light with a wavelength of 365 nm and a power of 150 W for 10 - 15 h to obtain a nano - composite hydrogel; The time for the polymerization reaction under the above - mentioned ultraviolet light is preferably 12 h; S3: Immerse the nano - composite hydrogel in glycerol for 4 - 6 h, and then immerse it in polyether - modified silicone oil for 4 - 6 h to obtain a nano - composite organic gel; The immersion time in glycerol and polyether - modified silicone oil is preferably 5 h; In addition, the mass ratio of the nano-composite hydrogel, glycerol, and polyether-modified silicone oil is all 1:10; S4: Perform shaping treatment on the nano-composite organic gel, and install a wire on the shaped nano-composite organic gel to obtain the multifunctional nano-composite organic gel strain sensor.
[0028] Of course, in the present invention, the above raw materials such as acrylic acid can be replaced with methacrylic acid, acrylamide, or dimethylaminoethyl methacrylate methyl ammonium chloride, which is also within the scope of the present invention; The above nano-silica can be replaced with iron oxide, carbon nanotubes, titanium dioxide, or graphene, which is also within the scope of the present invention; The above photoinitiator can be at least one of α-ketoglutaric acid, potassium persulfate, sodium persulfate, and ammonium persulfate; The above glycerol can be replaced with ethylene glycol, propylene glycol, diglycerol, or phosphatidylglycerol, and the above polyether-modified silicone oil can be replaced with silicone oil or dimethyl silicone oil, which is also within the scope of the present invention.
[0029] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.
[0030] Conventional instrument equipment in the art is used in the following embodiments. The experimental methods without specific conditions noted in the following embodiments are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer. Various raw materials are used in the following embodiments. Unless otherwise stated, commercially available products are used, and their specifications are conventional specifications in the art. In the specification of the present invention and the following embodiments, unless otherwise specified, "%" represents weight percentage, "parts" represents weight parts, and the ratio represents weight ratio.
[0031] Example 1 This example provides a multifunctional nano-composite organic gel strain sensor, and the strain sensing material includes a nano-composite organic gel.
[0032] The fracture strength of the nano-composite organic gel is 1.78 MPa; the toughness is 4.22 MJ / m 3 ; the Young's modulus is 0.23 MPa; the tear energy is 3163 J / m 2 , and the puncture strength is 1.72 MPa.
[0033] In this embodiment, the test standard for the nano - composite organic gel is GB1040 - 92, and the same applies to the other embodiments.
[0034] The preparation method of the multifunctional nano - composite organic gel strain sensor includes the following steps: Step 1: Preparation of the nano - composite hydrogel precursor solution: Disperse 1 g of polyvinyl alcohol (purchased from Aladdin, product number 9002 - 89 - 5) in 20 g of water to obtain a polyvinyl alcohol solution, and let it stand for later use; to achieve uniform dispersion of nanoparticles in the hydrogel matrix, stir 9 g of acrylic acid (purchased from Macklin, product number 79 - 10 - 7), 0.32 g of silica (purchased from Aladdin, product number 7631 - 86 - 9) and 0.04 g of α - ketoglutaric acid (purchased from Macklin, product number 328 - 50 - 7) initiator at 60 °C for 10 min to obtain a suspension of SiO2@PAA NPs. Subsequently, uniformly mix the polyvinyl alcohol solution, 2.54 g of lithium chloride (purchased from Macklin, product number 7447 - 41 - 8) and the SiO2@PAA NPs suspension to obtain the nano - composite hydrogel precursor solution; in this embodiment, the nano - silica accounts for 1% of the total mass of acrylic acid, nano - silica, photo - initiator, polyvinyl alcohol solution and lithium chloride. Step 2: Preparation of the nano - composite hydrogel: Let the nano - composite hydrogel precursor solution stand under vacuum at 20 °C for 1 h, pour it into a mold (the mold is made of two glass plates and a 1 - mm - thick perforated silicone pad), and place it in an ultraviolet box (wavelength 365 nm, power 150 W) for light irradiation for 12 h to obtain the nano - composite hydrogel. Step 3: Preparation of the nano - composite organic gel: After demolding the nano - composite hydrogel, place it in 312 g of glycerol (purchased from Kermel, product number 56 - 81 - 5) for 5 h of soaking. After taking it out, place it in 312 g of polyether - modified silicone oil (purchased from Macklin, product number NONE6743) for 5 h of soaking to obtain the nano - composite organic gel; here, the mass ratio of the nano - composite hydrogel to glycerol and polyether - modified silicone oil is 1:10. Step 4: Preparation of the nano - composite organic gel sensor: Make the nano - composite organic gel into the shape of a laparoscopic trocar seal (a 20 - mm - diameter round piece with a 2.5 - mm - diameter round hole in the center) using a cutter (a round cutter with a diameter of 2.5 mm), and install wires at both ends of the seal to assemble the nano - composite organic gel strain sensor.
[0035] Example 2 This embodiment provides a multifunctional nano - composite organic gel strain sensor, and the strain - sensing material includes a nano - composite organic gel.
[0036] The fracture strength of the nano-composite organic gel is 1.87 MPa; the toughness is 4.24 MJ / m 3 ; the Young's modulus is 0.25 MPa; the tearing energy is 5100 J / m 2 , and the puncture strength is 2.91 MPa.
[0037] In this embodiment, the test standard of the nano-composite organic gel is GB1040-92, and the same applies to the other embodiments.
[0038] The preparation method of the multifunctional nano-composite organic gel strain sensor comprises the following steps: Step 1: Preparation of the nano-composite hydrogel precursor solution: Disperse 1 g of polyvinyl alcohol (purchased from Aladdin, product number 9002-89-5) in 20 g of water to obtain a polyvinyl alcohol solution, and let it stand for later use; in order to achieve uniform dispersion of nanoparticles in the hydrogel matrix, stir 9 g of acrylic acid (purchased from Macklin, product number 79-10-7), 0.66 g of silica (purchased from Aladdin, product number 7631-86-9) and 0.04 g of α-ketoglutaric acid (purchased from Macklin, product number 328-50-7) initiator at 60 °C for 10 min to obtain a suspension of SiO2@PAA NPs. Subsequently, uniformly mix the polyvinyl alcohol solution, 2.54 g of lithium chloride (purchased from Macklin, product number 7447-41-8) and the SiO2@PAA NPs suspension to obtain the nano-composite hydrogel precursor solution; in this embodiment, the nano-silica accounts for 2% of the total mass of acrylic acid, nano-silica, photoinitiator, polyvinyl alcohol solution and lithium chloride; Step 2: Preparation of the nano-composite hydrogel: Let the nano-composite hydrogel precursor solution stand under vacuum at 20 °C for 1 h, pour it into a mold (this mold is made of two glass plates and a 1-mm-thick perforated silicone pad), and place it in an ultraviolet box (power 150 W) for light irradiation for 12 h to obtain the nano-composite hydrogel; Step 3: Preparation of the nano-composite organic gel: After demolding the nano-composite hydrogel, place it in 301 g of glycerol (purchased from Kermel, product number 56-81-5) for 5 h of soaking. After taking it out, place it in 301 g of polyether-modified silicone oil (purchased from Macklin, product number NONE6743) for 5 h of soaking to obtain the nano-composite organic gel; here, the mass ratio of the nano-composite hydrogel to glycerol and polyether-modified silicone oil is 1:10; Step 4: Preparation of the nano-composite organic gel sensor: Use a cutter (a circular cutter with a diameter of 2.5 mm) to make the nano-composite organic gel into the shape of a laparoscopic trocar seal (a round piece with a diameter of 20 mm and a round hole with a diameter of 2.5 mm at the center), and install wires at both ends of the seal to assemble the nano-composite organic gel strain sensor.
[0039] Example 3 This example provides a multifunctional nanocomposite organic gel strain sensor, and the strain sensing material includes a nanocomposite organic gel.
[0040] The fracture strength of the nanocomposite organic gel is 3.34 MPa; the toughness is 6.43 MJ / m 3 ; the Young's modulus is 0.62 MPa; the tear energy is 9153 J / m 2 , and the tear threshold is 4602 J / m 2 , and the puncture strength is 4.28 MPa.
[0041] In this example, the test standard for the nanocomposite organic gel is GB1040-92, and the same applies to the other examples.
[0042] The preparation method of the nanocomposite organic gel includes the following steps: Step 1: Preparation of the nanocomposite hydrogel precursor solution: Disperse 1 g of polyvinyl alcohol (purchased from Aladdin, product number 9002-89-5) in 20 g of water to obtain a polyvinyl alcohol solution, and let it stand for later use; in order to achieve uniform dispersion of nanoparticles in the hydrogel matrix, stir 9 g of acrylic acid (purchased from Macklin, product number 79-10-7), 1.01 g of silicon dioxide (purchased from Aladdin, product number 7631-86-9), and 0.04 g of α-ketoglutaric acid (purchased from Macklin, product number 328-50-7) initiator at 60 °C for 10 min to obtain a suspension of SiO2@PAA NPs. Subsequently, uniformly mix the polyvinyl alcohol solution, 2.54 g of lithium chloride (purchased from Macklin, product number 7447-41-8), and the SiO2@PAA NPs suspension to obtain the nanocomposite hydrogel precursor solution; in this example, the mass fraction of nano-silicon dioxide in the total mass of acrylic acid, nano-silicon dioxide, photoinitiator, polyvinyl alcohol solution, and lithium chloride is 3%; Step 2: Preparation of the nanocomposite hydrogel: Let the nanocomposite hydrogel precursor solution stand under vacuum at 20 °C for 1 h, pour it into a mold (this mold is made of two glass plates and a 1 mm thick hollow silicone pad), and place it in an ultraviolet box (power 150 W) for light irradiation for 12 h to obtain the nanocomposite hydrogel; Step 3: Preparation of the nanocomposite organic gel: After demolding the nanocomposite hydrogel, place it in 317 g of glycerol (purchased from Kermel, product number 56-81-5) and soak for 5 h. After taking it out, place it in 317 g of polyether-modified silicone oil (purchased from Macklin, product number NONE6743) and soak for 5 h to obtain the nanocomposite organic gel; Step 4: Preparation of the nano-composite organic gel sensor: The nano-composite organic gel was made into the shape of a laparoscopic trocar seal (a 20-mm-diameter disc with a 2.5-mm-diameter round hole in the center) using a cutter (a round cutter with a diameter of 2.5 mm). Wires were installed at both ends of the seal to assemble the nano-composite organic gel strain sensor.
[0043] Example 4 This example provides a multifunctional nano-composite organic gel strain sensor, and the strain sensing material includes the nano-composite organic gel.
[0044] The nano-composite organic gel has a fracture strength of 2.93 MPa; a toughness of 5.21 MJ / m 3 ; a tear energy of 5342 J / m 2 , and a puncture strength of 4.1 MPa.
[0045] In this example, the test standard for the nano-composite organic gel is GB1040-92, and the same applies to the other examples.
[0046] The preparation method of the nano-composite organic gel includes the following steps: Step 1: Preparation of the nano-composite hydrogel precursor solution: 1 g of polyvinyl alcohol (purchased from Aladdin, product number 9002-89-5) was dispersed in 20 g of water to obtain a polyvinyl alcohol solution, which was left standing for later use; to achieve uniform dispersion of the nanoparticles in the hydrogel matrix, 9 g of acrylic acid (purchased from Macklin, product number 79-10-7), 1.36 g of silica (purchased from Aladdin, product number 7631-86-9), and 0.04 g of α-ketoglutaric acid (purchased from Macklin, product number 328-50-7) initiator were stirred at 60 °C for 10 min to obtain a suspension of SiO2@PAA NPs. Subsequently, the polyvinyl alcohol solution, 2.54 g of lithium chloride (purchased from Macklin, product number 7447-41-8), and the SiO2@PAA NPs suspension were uniformly mixed to obtain the nano-composite hydrogel precursor solution; in this example, the nano-silica accounts for 4% of the total mass of acrylic acid, nano-silica, photoinitiator, polyvinyl alcohol solution, and lithium chloride; Step 2: Preparation of the nano-composite hydrogel: The nano-composite hydrogel precursor solution was left standing under vacuum at 20 °C for 1 h, poured into a mold (the mold was made of two glass plates and a 1-mm-thick perforated silicone pad), and placed in an ultraviolet box (with a power of 150 W) for 12 h of light irradiation to obtain the nano-composite hydrogel; Step 3: Preparation of nano-composite organic gel: After demolding the nano-composite hydrogel, it was placed in 309 g of glycerol (purchased from Comin, product number 56-81-5) for 5 h. After taking it out, it was placed in 309 g of polyether-modified silicone oil (purchased from Macklin, product number NONE6743) for 5 h to obtain the nano-composite organic gel; Step 4: Preparation of nano-composite organic gel sensor: The nano-composite organic gel was made into the shape of a laparoscopic trocar seal (a round piece with a diameter of 20 mm and a round hole with a diameter of 2.5 mm in the center) using a cutter (a round cutter with a diameter of 2.5 mm), and wires were installed at both ends of the seal to assemble the nano-composite organic gel strain sensor.
[0047] Example 5 The difference between this example and Example 3 is that in step S1, the mass ratio of polyvinyl alcohol to acrylic acid is 1:6.
[0048] Example 6 The difference between this example and Example 3 is that in step S1, the mass ratio of polyvinyl alcohol to acrylic acid is 1:3.
[0049] Comparative Example 1 The difference between this comparative example and Example 3 is that in step S1, nano-silica is not added in the preparation of the mixed suspension to obtain an organic gel.
[0050] The fracture strength of the organic gel prepared in this comparative example is 0.76 MPa; the toughness is 1.83 MJ / m 3 ; the Young's modulus is 0.15 MPa; the tear energy is 890 J / m 2 , and the tear threshold is 450 J / m 2 , and the puncture strength is 1.32 MPa.
[0051] By comparing some mechanical data of the multifunctional nano-composite organic gels prepared in Examples 1-4 and the organic gels prepared in the comparative examples, it can be seen that when the nano-silica accounts for 3% of the total mass of the system, the performance of the multifunctional nano-composite organic gel reaches the best.
[0052] Some mechanical property test results of the multifunctional nano-composite organic gels prepared in Example 3 and Examples 5-6 are shown in Table 1. It can be seen from Table 1 that when the mass ratio of polyvinyl alcohol to acrylic acid is 1:9, the performance of the multifunctional nano-composite organic gel reaches the best.
[0053] Table 1
[0054] In the table, m PVA represents the mass of polyvinyl alcohol, and m AArepresents the mass of acrylic acid; Example 7 The present invention provides a method for preparing a multifunctional nano - composite organic gel strain sensor, comprising the following steps: S1: Disperse 1 g of polyvinyl alcohol in 20 g of water to obtain a polyvinyl alcohol solution, and let it stand for later use; Mix 9 g of acrylic acid, 0.04 g of photo - initiator, and nano - silica with a size of 30 nm, and stir at 60 °C for 10 min to obtain the mixed suspension; Then mix the polyvinyl alcohol solution, the mixed suspension, and lithium chloride with a concentration of 3 mol / L uniformly to obtain a nano - composite hydrogel precursor solution; The nano - silica accounts for 0.5% of the total mass of acrylic acid, nano - silica, photo - initiator, polyvinyl alcohol solution, and lithium chloride.
[0055] S2: Let the nano - composite hydrogel precursor solution stand under vacuum for 20 min, and then initiate a polymerization reaction under ultraviolet light with a wavelength of 365 nm and a power of 150 W for 10 h to obtain a nano - composite hydrogel; S3: Immerse the nano - composite hydrogel in glycerol for 4 h, and then immerse it in polyether - modified silicone oil for 4 h to obtain a nano - composite organic gel; S4: Perform a shaping treatment on the nano - composite organic gel. During the shaping treatment, shape it into the shape of a laparoscopic trocar seal, that is, a disc with a diameter of 20 mm and a round hole with a diameter of 2.5 mm in the center, and install a wire on the shaped nano - composite organic gel to obtain the multifunctional nano - composite organic gel strain sensor.
[0056] The fracture strength of the multifunctional nano - composite organic gel strain sensor prepared in this example is 1.80 MPa, and the toughness is 4.25 MJ / m 3 ; The Young's modulus of the multifunctional nano - composite organic gel strain sensor is 0.30 MPa, and the time for the multifunctional nano - composite organic gel strain sensor to recover 90% at 60% strain is 500 s; The friction coefficient of the multifunctional nano - composite organic gel strain sensor is 0.15; The sensitivity of the multifunctional nano - composite organic gel strain sensor is 0.9.
[0057] Example 8 The present invention provides a method for preparing a multifunctional nano - composite organic gel strain sensor, comprising the following steps: S1: Disperse 1 g of polyvinyl alcohol in 20 g of water to obtain a polyvinyl alcohol solution, and let it stand for later use; mix 9 g of acrylic acid, 0.04 g of photoinitiator, and nanosilica with a size of 60 nm, and stir at 60 °C for 10 min to prepare the mixed suspension; then mix the polyvinyl alcohol solution, the mixed suspension, and lithium chloride with a concentration of 3 mol / L evenly to prepare a nanocomposite hydrogel precursor solution; The nanosilica accounts for 4% of the total mass of acrylic acid, nanosilica, photoinitiator, polyvinyl alcohol solution, and lithium chloride.
[0058] S2: Let the nanocomposite hydrogel precursor solution stand under vacuum for 30 min, and then initiate a polymerization reaction under ultraviolet light with a wavelength of 365 nm and a power of 150 W for 15 h to obtain a nanocomposite hydrogel; S3: Immerse the nanocomposite hydrogel in glycerol for 6 h, and then immerse it in polyether-modified silicone oil for 6 h to obtain a nanocomposite organic gel; S4: Perform a shaping treatment on the nanocomposite organic gel. During the shaping treatment, it is processed into the shape of a laparoscopic trocar seal, that is, a disc with a diameter of 20 mm and a round hole with a diameter of 2.5 mm in the center, and install a wire on the shaped nanocomposite organic gel to obtain the multifunctional nanocomposite organic gel strain sensor.
[0059] The fracture strength of the multifunctional nanocomposite organic gel strain sensor is 2.05 MPa, and the toughness is 5.51 MJ / m 3 ; The Young's modulus of the multifunctional nanocomposite organic gel strain sensor is 0.55 MPa, and the time for the multifunctional nanocomposite organic gel strain sensor to recover 90% under 60% strain is 553 s; The friction coefficient of the multifunctional nanocomposite organic gel strain sensor is 0.17; The sensitivity of the multifunctional nanocomposite organic gel strain sensor is 1.2.
[0060] Example 9 The present invention provides a preparation method of a multifunctional nanocomposite organic gel strain sensor, including the following steps: S1: Disperse 1 g of polyvinyl alcohol in 20 g of water to obtain a polyvinyl alcohol solution, and let it stand for later use; mix 9 g of acrylic acid, 0.04 g of photoinitiator, and nanosilica with a size of 50 nm, and stir at 60 °C for 10 min to prepare the mixed suspension; then mix the polyvinyl alcohol solution, the mixed suspension, and lithium chloride with a concentration of 3 mol / L evenly to prepare a nanocomposite hydrogel precursor solution. The nanosilica accounts for 2% of the total mass of acrylic acid, nanosilica, photoinitiator, polyvinyl alcohol solution, and lithium chloride.
[0061] S2: Let the nanocomposite hydrogel precursor solution stand under vacuum for 20 - 30 min, and then initiate a polymerization reaction under ultraviolet light with a wavelength of 365 nm and a power of 150 W for 12 h to prepare a nanocomposite hydrogel. S3: Immerse the nanocomposite hydrogel in glycerol for 5 h, and then immerse it in polyether-modified silicone oil for 5 h to prepare a nanocomposite organogel. S4: Perform a shaping treatment on the nanocomposite organogel. During the shaping treatment, shape it into the shape of a laparoscopic trocar seal, that is, a disc with a diameter of 20 mm and a round hole with a diameter of 2.5 mm in the center, and install a wire on the shaped nanocomposite organogel to prepare the multifunctional nanocomposite organogel strain sensor.
[0062] The fracture strength of the multifunctional nanocomposite organogel strain sensor is 2.21 MPa, and the toughness is 5.02 MJ / m 3 ; The Young's modulus of the multifunctional nanocomposite organogel strain sensor is 0.52 MPa, and the time for the multifunctional nanocomposite organogel strain sensor to recover 90% under 60% strain is 541 s; The friction coefficient of the multifunctional nanocomposite organogel strain sensor is 0.2; The sensitivity of the multifunctional nanocomposite organogel strain sensor is 1.5.
[0063] Perform relevant performance measurements on the nanocomposite organogel strain sensor prepared in the above Example 3 to obtain the mechanical and electrical properties of the nanocomposite organogel.
[0064] Figure 2 is the stress-strain diagram of the nanocomposite organogel obtained according to the standard tensile test. According to relevant calculations, the toughness of the organogel is 6.43 MJ / m 3 , indicating that the nanocomposite organogel has a high fracture toughness.
[0065] Figure 3 The stress-strain diagrams of the nano-composite organic gel under loading-unloading at different rest times obtained from the standard tensile test. According to relevant calculations, the recovery rate of the organic gel within 600 s is 90%, indicating that the nano-composite organic gel has a fast self-recovery property.
[0066] Figure 4 is the stress-fracture elongation curve of the nano-composite organic gel obtained from the pure shear test. According to relevant calculations, the tear energy of the organic gel is 9153 J / m 2 , indicating that the nano-composite organic gel has a high tear resistance.
[0067] Figure 5 is a schematic diagram of the puncture resistance of the multifunctional nano-composite organic gel described in Example 3. It can be seen from the figure that the nano-composite organic gel exhibits excellent puncture resistance when subjected to a puncture force.
[0068] Figure 6 is the puncture force-puncture distance curve of the nano-composite organic gel obtained from the quasi-static puncture test. According to relevant calculations, the maximum puncture stress of the organic gel is 4.28 MPa, indicating that the nano-composite organic gel has a high puncture resistance.
[0069] Figure 7 is a schematic diagram of the insertion of the multifunctional nano-composite organic gel described in Example 3. It can be seen from the figure that when the puncture needle is inserted into the organic gel, no tearing phenomenon occurs in the gel, indicating that the nano-composite organic gel has excellent mechanical properties and can effectively maintain the structural integrity during the insertion and extraction process.
[0070] Figure 8 is the maximum insertion force and extraction force of the nano-composite organic gel during 500 cycles of insertion-extraction obtained from the simulated laparoscopic surgery operation. The maximum insertion force and the maximum extraction force both remain at 0.80 - 0.95 N, indicating the stability of the nano-composite organic gel during long-term insertion-extraction.
[0071] Figure 9 is the friction coefficient diagram of the multifunctional nano-composite organic gel and traditional sealant materials under different pressures, indicating that the multifunctional nano-composite organic gel exhibits a low friction coefficient under different pressures.
[0072] Figure 10 is the water retention test of the nano-composite organic gel at 25 °C. Even after 30 days of placement, the weight ratio remains stable, indicating the excellent water resistance and environmental stability of the nano-composite organic gel.
[0073] Figure 11It is the corrosion test of the nano - composite organic gel on surgical instruments. The gel sample was adhered to a 4Cr13 plate with the same material as laparoscopic surgical instruments and exposed to air for 3 days. No signs of corrosion appeared on the surface of the 4Cr13 plate. On the contrary, the 4Cr13 plate adhered with the nano - composite hydrogel showed serious and irreversible corrosion, indicating the excellent corrosion resistance of the nano - composite organic gel.
[0074] Figure 12 It is the air - tightness schematic diagram of the multifunctional nano - composite organic gel obtained according to the standard laparoscopic trocar air - tightness test, indicating that the multifunctional nano - composite organic gel has good air - tightness.
[0075] Figure 13 It is the resistance change curve of the nano - composite organic gel strain sensor during the stretching process. According to relevant calculations, when the strain is 0 - 100%, the sensitivity of the sensor is 0.904; when the strain is 100% - 300%, the sensitivity of the sensor is 1.374; when the strain is 300% - 661%, the sensitivity of the sensor is 1.945.
[0076] Figure 14 It is the relationship curve of the resistance of the nano - composite organic gel strain sensor with respect to time under different strains, indicating that the nano - composite organic gel strain sensor can detect small strains and has stable and repeatable sensing performance.
[0077] Figure 15 It is the relationship curve of the resistance of the nano - composite organic gel strain sensor with respect to time during 800 cycles of plugging and unplugging, indicating that the nano - composite organic gel strain sensor shows fast and repeatable sensing performance within 800 cycles.
[0078] Figure 16 It is the schematic diagram of the multifunctional nano - composite organic gel sensor during the simulated laparoscopic surgery operation, indicating that the nano - composite organic gel strain sensor shows stable and distinguishable sensing performance during multiple artificial insertions and extractions.
[0079] Therefore, the nano - composite organic gel strain sensor described in the present invention is applied to the real - time monitoring in laparoscopic surgery, realizing the conversion between resistance change and insertion - extraction actions, converting the actions of surgeons into visual data, and providing good guidance for doctors to fully understand hand movements and adjust in a timely manner.
[0080] Similar results were obtained in other embodiments. In general, the intelligent sealing sensing system based on the strain - sensing material described in the present invention is expected to be applied to the real - time monitoring in laparoscopic surgery.
[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.
Claims
1. A preparation method of a multifunctional nano-composite organic gel strain sensor, characterized in that, It includes the following steps: S1: After uniformly mixing acrylic acid, nano-silica, and a photoinitiator, a mixed suspension is prepared; then, after uniformly mixing a polyvinyl alcohol solution, lithium chloride, and the mixed suspension, a nano-composite hydrogel precursor solution is prepared; S2: After subjecting the nano-composite hydrogel precursor solution to a static treatment under vacuum, a polymerization reaction is initiated under ultraviolet light to obtain a nano-composite hydrogel; S3: After soaking the nano-composite hydrogel in glycerol and then soaking it in polyether-modified silicone oil, a nano-composite organic gel is obtained; S4: The nano-composite organic gel is subjected to a shaping treatment, and a wire is installed on the shaped nano-composite organic gel to obtain the multifunctional nano-composite organic gel strain sensor.
2. The preparation method of a multifunctional nano-composite organic gel strain sensor according to claim 1, characterized in that The size of the nano-silica is 30 - 60 nm.
3. The preparation method of a multifunctional nano-composite organic gel strain sensor according to claim 1, characterized in that, The mass ratio of polyvinyl alcohol to acrylic acid is 1:(9 - 3).
4. The preparation method of a multifunctional nano-composite organic gel strain sensor according to claim 1, characterized in that, The nano-silica accounts for 0.5% - 4% of the total mass of acrylic acid, nano-silica, photoinitiator, polyvinyl alcohol solution, and lithium chloride.
5. The preparation method of a multifunctional nano-composite organic gel strain sensor according to claim 1, characterized in that, The concentration of lithium chloride is 3 mol / L.
6. The preparation method of a multifunctional nanocomposite organic gel strain sensor according to claim 1, characterized in that, In step S2, the time for subjecting the nano-composite hydrogel precursor solution to a static treatment under vacuum is 20 - 30 min.
7. The preparation method of a multifunctional nano-composite organic gel strain sensor according to claim 1, characterized in that, In step S2, when irradiated with ultraviolet light, the wavelength is 365 nm and the time is 10 - 15 h.
8. The preparation method of a multifunctional nano-composite organic gel strain sensor according to claim 1, wherein, In step S3, the time for soaking the nano-composite hydrogel in glycerol is 4 - 6 h; the time for soaking it in polyether-modified silicone oil is 4 - 6 h.
9. A multifunctional nano-composite organic gel strain sensor, characterized in that, Prepared by the method according to any one of claims 1 to 8; the fracture strength of the multifunctional nanocomposite organic gel strain sensor is 1.78 to 3.31 MPa, and the toughness is 4.22 to 6.43 MJ / m 3 ; The Young's modulus of the multifunctional nano-composite organic gel strain sensor is 0.23 - 0.64 Mpa, and the time for the multifunctional nano-composite organic gel strain sensor to recover 90% under 60% strain is 500 - 600 s; The friction coefficient of the multifunctional nano-composite organic gel strain sensor is 0.1 - 0.2; The sensitivity of the multifunctional nano-composite organic gel strain sensor is 0.9 - 2.
10. Application of the multifunctional nano-composite organic gel strain sensor described in claim 9 in the preparation of a laparoscopic trocar seal.