HIGH-PERFORMANCE SELF-HEALING POLYMER COMPOSITE MATERIALS CONTAINING DAP RESIN-FILLED CERAMIC CAPSULES.

Abstract

The invention relates to high-performance self-healing polymer composite materials for use in automotive, aerospace, electronics, and industrial machinery, etc. Specifically, the invention concerns self-healing polymer composite materials and their manufacturing method, which enable the automatic repair of microcracks and damage by incorporating ceramic capsules filled with DAP (Diallyl Phthalate) resin.

Description

1 TARIFF HIGH-QUALITY CERAMIC CAPSULES CONTAINING DAP RESIN-FILLED CERAMIC CAPSULES. HIGH-PERFORMANCE SELF-HEATING POLYMER COMPOSITE MATERIALS Technical Area The invention is suitable for use in automotive, aviation, space, electronics, and industrial machinery, etc. It relates to high-performance self-healing polymer composite materials. The invention is particularly characterized by its inclusion of ceramic capsules filled with DAP (Diallyl Phthalate) resin. Self-healing system that enables automatic repair of microcracks and damage. It deals with polymer composite materials and their production methods. State of the Art Today, high-performance engineering materials offer energy efficiency, lightness, and with increasing durability requirements, in the form of more complex and multifunctional structures. These materials are designed to withstand microcracks that occur during service conditions. They may experience a loss of performance due to fatigue injuries or environmental factors and 15 As a result, this can lead to increased maintenance costs or decreased structural reliability. This can lead to the need for damage assessment or maintenance procedures. Smart materials that can reduce emissions and self-heal are an important area of ​​research. It has established itself. Self-healing materials developed within this scope are based on biomimetic approaches. It is resistant and actively demonstrates the ability to heal when damage occurs. This These systems, thanks to the presence of low molecular weight repair agents, can repair microcracks and It can self-repair superficial damage. The repair agents are microcapsules. 25 within different architectures such as vascular networks or polymeric carrier structures They can be positioned in various locations. These features are particularly useful in hard-to-reach areas or where maintenance costs are high. in critical infrastructure and transportation applications where high demand is present (bridges, aircraft structures, automotive (components) aim to extend material life and reduce maintenance needs. While current self-healing systems offer significant advantages, they have certain limitations. 30 It has high production costs, limited repair capacity, and is related to the extent of the damage. Long recovery times and performance losses attributable to environmental conditions affect these systems. 2 These are the main disadvantages of thermoset materials, for example, those based on diallyl phthalate (DAP). Although resins offer high mechanical strength and thermal stability, they are suitable for high temperatures. and due to curing processes carried out under pressure, production processes take a long time. It requires a lot of time and high costs. Ceramic capsules, thanks to their high temperature and chemical resistance, protect repair agents. They are advantageous in terms of being able to store things safely. However, due to their fragile structure... They may break prematurely during production or under service conditions; this situation necessitates repair. the release of the agent before damage occurs or a delay in its release during damage This can cause problems such as reducing the overall efficiency of capsule-based systems. It limits. The prominent technical problems in the literature can be summarized as follows: the production of existing systems. Due to the high cost and the fragility of ceramic capsules, the repair agent Failure to release it in time, DAP-based self-contained 15 for high-temperature applications The fact that repairing composites have been addressed in a limited number of studies. Therefore, the technique... In its known state, it is effective, economical, reliable, and long-lasting under high temperature conditions. and a need for self-healing materials solution that reduces maintenance requirements It is heard. In the literature review, TR 2023 / 003360 is given as an example of the known state of the art. Application number [number] can be shown. The relevant application concerns a styrene block copolymer-based self-healing system. This relates to thermoplastic elastomers (TPEs) and the methods of producing these elastomers. The method mentioned involves mixing styrene block copolymer with a plasticizer and letting it sit to create the block. Copolymer blowing, styrene block copolymer and plasticizer mixture with maleic anhydride 25 or forming elastomer blends by combining maleic acid copolymers, elastomer Adding and mixing a ring-shaped amine compound to the mixture, elastomer mixture, metal salt by adding, mixing and kneading, maleic anhydride or maleic acid groups and amines the steps involved in forming complex and / or chelate bonds between the compound and the metal It includes. However, the document specifically mentions DAP resin-filled ceramic capsules and 30 Composite materials containing this are not mentioned. In conclusion, due to the negative aspects described above and the current solutions, the subject matter... Due to its shortcomings, an improvement is needed in the relevant technical field. It has been made. 35 3 Purpose of the Invention The present invention meets the aforementioned requirements while eliminating all disadvantages. ceramic capsules filled with DAP resin, which remove and offer some additional advantages. It relates to high-performance self-healing polymer materials. 5 The primary purpose of the invention is to treat microcracks caused by mechanical, thermal or environmental factors. and its self-healing capability that can automatically repair damage. The aim is to provide polymer matrix materials. The aim of the invention is to create a serviceable system that can maintain its structural integrity even under high temperature conditions. The goal is to create a reliable product that extends its lifespan and reduces maintenance requirements. One aim of the invention is to create ceramic capsules filled with DAP (diallyl phthalate) resin. using both high mechanical strength and effective self-healing capability 15 The goal is to develop structures that offer these services. Another aim of the invention is to address premature fracture caused by the fragility of ceramic capsules. or problems such as repair agent release delay can be caused by capsule geometry, material stiffness and The goal is to minimize the distribution ratios by optimizing them. 20 Another objective of the invention is to allow the capsules to be broken open in a controlled manner upon damage, thus releasing the repair agent. The goal is to ensure a rapid and sufficient release of the substance. Another objective of the invention is to improve the thermal stability and mechanical strength of DAP resin. Self-healing, suitable for high-temperature applications by taking advantage of its properties. Our goal is to offer polymer materials. Another aim of the invention is to reduce production costs while maintaining system performance or An economically advantageous 30 with an optimized capsule volume ratio and distribution that increases volume. The goal is to provide a solution. Another purpose of the invention is for automotive, aerospace, electronics and heavy industrial machinery. Flexible, reliable and high-performance for use in a wide range of applications. The goal is to develop self-healing materials. 35 4 To achieve the purposes described above, the invention involves a self-healing composite. The material consists of a polymer matrix and dialyl phthalate dispersed within the aforementioned polymer matrix. It contains ceramic capsules filled with (DAP) resin. To achieve the purposes described above, the invention is a self-healing composite 5 It is a material production method and includes the following steps: i. Coating polystyrene (PS) foam particles with ceramic clay, ii. Pre-drying of coated PS particles, iii. coating the pre-dried particles a second time with ceramic clay, iv. Sintering of double-coated PS particles to form hollow ceramic capsules. 10 obtaining, v. Filling hollow ceramic capsules with DAP resin under vacuum, vi. sealing the filling mouths of the filled capsules with ceramic clay, vii. Placement of capsules enclosed in a polymer matrix, viii. Shaping and hardening of the composite structure 15 The structural and characteristic features and all the advantages of the invention are given in the figures below. Thanks to the detailed explanation written with references to the figures, it becomes clearer. This will be understood. Therefore, the evaluation should also take these figures and detailed explanations into account. It must be done by taking 20. Figures that will help understand the invention. Figure 1, SEM image of a single capsule viewed at 35x magnification. Figure 2, Capsule wall thickness and SEM image. Figure 3, FTIR results of DAP resin and curing agent 25 Figure 4, TGA / DTA test results. Figure 5, DSC test results. Figure 6, Single capsule compression test results. Figure 7 shows the compression test results of samples made from epoxy matrix. Detailed Description of the Invention This detailed explanation of the invention is solely for the purpose of providing a better understanding of the subject. and is explained in a way that will not create any limiting effects. The invention relates to a self-healing composite material, the material in question being a polymer. Matrix and ceramic with DAP resin filler dispersed within the aforementioned polymer matrix. It contains capsules. The ceramic capsules described in the invention are preferably coated onto polystyrene particles. It is made of ceramic clay coating. The aforementioned ceramic capsules are polystyrene. shell structure created by applying a ceramic clay coating to the particles These ceramic capsules are designed to form a sintered hollow capsule volume. It is being prepared. The invention's working principle begins with ceramic capsules filled with DAP resin. Ceramic The capsules safely store the repair agent under high temperatures and chemical conditions. It retains and releases substances that will fill cracks when damage occurs. The matrix-phase interface within the composite material is the area between the capsules and the DAP resin. It contributes to an effective repair process by optimizing interaction. In case of damage, 20 The activated crack detection zone causes the capsules to rupture and the resin to release in a controlled manner. It triggers the release of the repair agent. In addition, the macrostructure of the capsules allows the repair agent to penetrate the crack. It ensures an even distribution throughout the region. The thermal triggering mechanism used in the invention is based on changes in matrix temperature. It supports classic self-repair behavior. 25 Thus, the basic principle of the invention is the crack detection and processing of ceramic capsules filled with DAP resin. Automatic repair agent release to fill damaged areas, matrix-phase interface efficient transfer of mechanical loads through and both thermal and practical A reliable self-healing system tested with application examples. It is the creation of. 30 The invention involves the formation of a matrix-phase interface. This interface is a ceramic capsule shell. It refers to the boundary region that naturally forms between the polymer matrix and the product during the manufacturing process. This boundary region: The microporous and rough structure of the ceramic capsule surface, Matrix Penetration of the resin (epoxy or DAP) into the capsule surface during curing, Physical 35 6 a matrix-phase transition that occurs spontaneously as a result of binding and limited surface interactions It is the region. The invention does not involve any surface modification, silane coating, primer application or chemical treatment. No bonding interface layer was used. Therefore, the behavior of the interface is capsule-matrix 5. It represents the natural binding mechanisms of interaction and the realistic mechanics of the system. and reflects healing behavior. This approach is particularly relevant during fracture progression. capsule rupture and release of healing agents occurring without external intervention It was chosen for the purpose of examination. In this context, matrix-capsule interface optimization is based on the following elements: has been accomplished: • Maintaining the surface roughness and microporosity of the ceramic capsule, • The vacuum-assisted DAP filling method ensures that capsule integrity is not compromised. • Curing conditions (temperature, time) of the matrix resin affect capsule-matrix contact. adjusted in a way that will not cause damage, • Ensuring homogeneous distribution of capsules within the matrix. This approach enables sufficient mechanical interlocking at the capsule-matrix interface. during this process, premature rupture of the capsule during crack progression or excessive It is secured by being strongly bound to prevent breakage. 20 In this invention, stress concentration occurs naturally during crack propagation and capsule formation. The local volume where the fracture is triggered can be defined as the crack detection zone. This crack It interacts with the capsule, breaking it open and thereby releasing the healing agent. is left behind. Activation of the capsules by the crack, crack 25 in the matrix thanks to the natural stress concentrations that develop depending on its progression It is happening. The invention involves a thermally triggerable, encapsulated therapeutic agent (DAP) and matrix system. It demonstrates temperature-dependent rheological and curing behavior. 30 The invention consists of liquid monomer in diallyl phthalate (DAP) resin capsules. It is in the form of a semi-solid or pre-packaged form when DAP is placed inside the capsule. It is not in a cured phase. 35 7 The subject of this invention is a method for producing self-healing composite materials; the following process applies: It includes the steps. i. Coating polystyrene (PS) foam particles with ceramic clay, ii. Pre-drying of coated PS particles, iii. coating the pre-dried particles a second time with ceramic clay, 5 iv. Hollow ceramic capsules formed by sintering double-coated PS particles. obtaining, v. Filling hollow ceramic capsules with DAP resin under vacuum, vi. sealing the filling mouths of the filled capsules with ceramic clay, vii. Placement of capsules enclosed in a polymer matrix, 10 viii. Shaping and hardening of the composite structure. In the second process step of the method described in the invention, the coated PS particles are preferably preheated at 60 °C. It undergoes a drying process. The invention involves PS double-coating with ceramic clay in the fourth process step. The particles are formed into hollow ceramic capsules by sintering, preferably at 1040 °C for 12 hours. is obtained. In one application of the method described in the invention, DAP resin is filled into capsules using vacuum 20 This is carried out using the assisted infiltration method. In this method, the inside of ceramic capsules The voids are filled with a vacuum, removing the air inside. Then the liquid... The DAP in this state penetrates the capsule cavities under the influence of atmospheric pressure. Thus A homogeneous and void-free filling is ensured within the capsule. This method is performed under pressure. Compared to injection or capillary infiltration, the fragile structure of ceramic capsules 25 This allows for effortless filling and preserves the integrity of the capsule shell. He knows. DAP is stored in an unreacted, active, and fluid state within the capsule; cracks When the capsule ruptures during formation, fluid freely flows into the crack volume, aiding in healing. It triggers the mechanism. 30 The invention involves ceramic capsules filled with DAP resin that have high temperature and chemical resistance. It offers self-healing composite materials developed using these methods. The material works on the principle that when damage occurs, the ceramic capsules break apart. By releasing the DAP resin inside and filling the cracks, the material regains its strength. It is based on winning. 8 In the method described in the invention, the distribution of ceramic capsules within a composite matrix is ​​an active process. without using orientation, arrangement or layered placement methods, but in a controlled manner. This distribution was achieved in a statistically random manner. This distribution is based on the direction of crack development and regardless of their location, increasing the likelihood of capsules interacting with the fracture 5 It represents a general-purpose (isotropic) approach aimed at achieving this. In an application of the method that is the subject of the invention, the composite structure mentioned in step viii. The shaping and hardening process includes the following:  Preparation of a mold with geometric dimensions suitable for the compression (pressing) sample, 10 pouring the polymer matrix in liquid form into the prepared mold,  then, depending on the type of polymer matrix used, at room temperature or curing at elevated temperatures In epoxy-based matrices, the curing process is carried out by adding a suitable hardener. During this process, the hardening process in DAP resin-based matrices is carried out using thermal curing. 15 This is carried out in order to demonstrate the functionality of the invention. This information is provided and does not limit the scope of protection of the invention. The invention provides high temperature and chemical resistance with ceramic capsules. The capsules safely protect the repair agent under production and usage conditions. 20 Heterogeneous composite structure in the invention: Combination of DAP resin with ceramic capsules, It provides high mechanical performance and effective repair. The invention has potential for high-performance applications in the automotive and aerospace industries. available. Experimental Studies and Results In the preliminary work carried out for the invention, a mixture containing 55% silicon dioxide (SiO₂) and 17% Al₂O₃ was used. Refsan (Türkiye) produced ceramic casting clay, thermoset class DAP resin, 30 Peroxide-based hardener and Ecomar R15 epoxy AB resins were used. For capsule production, polystyrene (PS) foam granules are coated with ceramic clay and a two-stage process is carried out. It has undergone a coating-drying process. In the first coating, pre-drying was done at 60 °C, Then a second coating was applied. The capsules were sintered at 1040 °C for 4 hours, this process 9 During this process, the PS foam melted, forming a hollow ceramic shell. The initial coating was thin and... While one coating created a fragile shell structure, the second coating provided a more rigid shell. The average diameter of the capsules produced was 4.5 ± 0.2 mm (Figure 1), and the average shell thickness was 150 ± It was determined to be 18 µm (Figure 2). Empty capsules were vacuumed with DAP resin or 5 filled with peroxide-based hardener, the filling voids are then refilled with ceramic clay. It has been closed and made ready to be placed inside the matrix. Considering that the peroxide-based hardener is added to the mixture during application When this happens, the system transforms from a single-component structure to a two-component reaction system. Characterization of DAP Resin To determine the chemical structure, thermal stability, and thermal transfer behavior of DAP resin. For this purpose, FTIR, TGA / DTA and DSC analyses were performed. FTIR Analysis 15 DAP resin, hardener, and the resulting structure after curing are processed using a Shimadzu IRTracer–100 machine. It was examined using the FTIR test. The FTIR results are given in Figure 3. Analysis results: DAP The spectrum of the resin shows a distinct carbonyl (C=O) peak around 1700 cm⁻¹, and between 1200 and 1000. C–O and C–H vibrations in cm⁻¹ regions, 3000 cm⁻¹ in peroxide-based hardener. Alkene C–H vibrations around this area, carbonyl 20 in the 1700 cm⁻¹ region in the post-curing structure Chemical peaks have been detected. These findings indicate that both the resin and the cured product are chemically... This demonstrates the accuracy of its structure and its usability as a therapeutic agent. TGA / DTA Analysis TGA analysis was performed on a Shimadzu DTG-60H instrument. 25 Findings: No significant mass loss was observed between 0–300 °C, and the structure was found to be stable. 300– A rapid and intense mass loss occurred in the 400 °C range. After 400 °C... It has been determined that almost all of the mass has disappeared and the structure has completely decomposed. DTA An endothermic peak was observed in the same region of the curve, indicating the breaking of chemical bonds. This corresponds to the exothermic response observed after 400 °C, combustion, or 30. It has been an indicator of carbonization. In conclusion, the thermal degradation limit of DAP resin is in the range of 300–400 °C. Above 350 °C High temperatures cause the resin to lose its stability, therefore avoid high temperatures. In exposed composite applications, the 320–340 °C range is considered the upper limit. It can be evaluated. 35 DSC Analysis DSC testing was performed using a TA Instruments DSC-25 device in an argon environment, with heating and cooling at 5 °C / min. The analysis was performed at a certain rate. Analysis results: A distinct endothermic peak at 175.69 °C was observed in the material. It shows a phase change. The initial (onset) temperature was measured as 109.23 °C. 5 The enthalpy value was calculated as 17.923 J / g. In the exothermic curve, polymerization or... Heat output indicating crystallization was observed. This data suggests that the thermal transition of DAP resin... Understanding their behavior and compatibility with the composite matrix is ​​critical. Compression Test Results Approximately 20 capsules are added to the epoxy matrix samples prepared according to the ASTM D695 standard. They were placed, 16 of which were filled with DAP and 4 with peroxide-based hardener. Each set Five repetitions were performed for this. Furthermore, the compressive strength of individual capsules with a diameter of 4 ± 0.5 mm was found to be 2. Tested at a speed of mm / min. 15 The durability varies according to capsule type as follows: DAP-filled capsules showed the highest strength (35 ± 0.98 N). Filling material It has increased the load-bearing capacity by supporting the shell. Sudden increase after the maximum point. A fracture was observed. 20 Empty capsules: showed the lowest strength (10 ± 0.63 N). Low load-carrying capacity. and exhibited ductile behavior. Peroxide-filled capsules: showed moderate strength (20 ± 0.86 N). More regular and It exhibited ductile fracture behavior. The energy absorption values ​​are as follows:  DAP-filled capsules: 29.56 ± 1.42 N·mm  Erection-enhanced capsules: 20.4 ± 2.01 N·mm  Empty capsules: 11.36 ± 0.92 N·mm In DAP matrix samples: 63.5% after the first recovery, 56% after the second recovery. Improvement efficiency has been achieved. Pure DAP matrix has the highest strength as a reference. It has provided. Although composite materials containing fillers do not exhibit the same strength as pure matrix, the presence of capsules reduces the load. It contributed to the load-bearing capacity. Empty capsules provided low strength, but fracture was 35. It has shown potential in terms of controlling behavior. 11 Capsule-matrix interface interaction directly affects mechanical performance. In the DAP matrix: the polar phthalate ester groups within the DAP interact with the –OH groups in the ceramic shell. It has formed secondary hydrogen bonds. Microscopic features formed on the shell surface after sintering. The roughness reduced capsule displacement by providing mechanical locking. 5 In the epoxy matrix: Chemical bond formation is not expected. Surface roughness. Thanks to this, the epoxy shell has filled the micro-pores, creating a physical bond. Furthermore... The weak interface facilitated capsule fracture during crack propagation. Consequently, in both matrices, the interface is functionally related to capsule stability and fracture vulnerability. It has established a balance. 10 According to the results obtained, ceramic capsules are suitable for high temperature and chemical environments. It is durable. DAP resin, as a curing agent, is resistant to thermal, chemical, and mechanical stress. It is suitable. Compression tests have shown that the capsules can effectively increase material strength. This has been demonstrated. The capsule fill level significantly affects mechanical performance. It affects both capsule stability and fracture resistance. 15 It plays a critical role in the healing mechanism. Healing efficiencies are achieved with DAP resin-filled capsules. This confirms that it works effectively in the matrix. These results indicate a self-healing process. Composites offer significant advantages in terms of sustainability, strength, and cost. that it can provide; especially in automotive, construction and high-temperature applications, it is a powerful tool. This shows that it has potential. 20

Claims

12 REQUESTS 1. It is a self-healing composite material, the characteristic of which is;  Polymer Matrix and 5  Diallyl Phthalate (DAP) resin filled within the aforementioned polymer matrix ceramic capsules It includes.

2. The material conforming to Claim 1 is characterized by its properties as follows: the aforementioned ceramic capsules are made of polystyrene 10. shell structure created by applying a ceramic clay coating to the particles It is having.

3. The material conforms to Claim 1 and is characterized by being epoxy-based and / or DAP resin-based. It contains a polymer matrix. 15 4. It is a self-healing composite material production method, the characteristic of which is; i. Coating polystyrene (PS) foam particles with ceramic clay, ii. Pre-drying of coated PS particles, iii. coating the pre-dried particles a second time with ceramic clay, 20 iv. Hollow ceramic capsules formed by sintering double-coated PS particles. obtaining, v. Filling hollow ceramic capsules with DAP resin under vacuum, vi. sealing the filling mouths of the filled capsules with ceramic clay, vii. Placement of capsules enclosed in a polymer matrix, 25 viii. Shaping and hardening of the composite structure It includes the steps involved in the process.

5. The method according to claim 4, its characteristic is; in the second process step, pre-30 for 6 hours at 60 °C. The drying process is applied.

6. This method is based on claim 4 and its characteristic is that in step 4, the process involves heating at 1040 °C for 4-12 hours. It is sintering. 35 13 7. The method according to claim 4, its characteristic is; v. In the process step, hollow ceramic capsules It is a method of filling with liquid DAP resin using vacuum-assisted infiltration.

8. The method according to claim 4, its characteristic is; vii. In the process step, an epoxy-based matrix and / or DAP is the placement of capsules into a resin-based matrix. 5

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