Composite material based on polyborosiloxane interpenetrating polymer network as well as preparation method and application of composite material

Abstract

The invention discloses a composite material based on a polyborosiloxane interpenetrating polymer network as well as a preparation method and application of the composite material, and belongs to the technical field of polymer composite materials. The invention provides a composite material based on a polyborosiloxane interpenetrating polymer network and a preparation method of the composite material. Polyborosiloxane is used as a matrix, and trace polymer components (polyvinylpyrrolidone, polyvinyl alcohol, chitosan and the like) are introduced; by utilizing multiple dynamic interaction between boron hydroxyl of tetrahydroxydiborane and a doped molecular chain, namely a synergistic crosslinking system containing boron ester bonds, boron-nitrogen coordination bonds and boron-oxygen coordination bonds, a matrix and the doped molecular chain are forced to be connected to form an interpenetrating network, so that the mechanical property and the impact resistance of the polyborosiloxane are remarkably improved. Through dynamic bond chemical design and inorganic-organic hybrid structure innovation, the material has important application value in the fields of flexible electronic packaging and impact-resistant protective materials.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer composite materials, and in particular relates to a composite material based on a polyborosiloxane interpenetrating polymer network, and a preparation method and application thereof. Background Art

[0002] With the rapid development of science and technology, electronic products are moving towards integration, precision, flexibility and thinness at an unprecedented speed. However, as electronic products develop towards higher integration, more precise structure, greater flexibility and thinner form, their reliability issues are becoming increasingly prominent. Especially when facing external shocks or vibrations, these advanced electronic devices are easily damaged, destroyed or even fail, which not only affects the service life and performance stability of the products, but also brings inconvenience and economic losses to users, becoming a bottleneck restricting the development of the industry. Therefore, how to effectively protect these precision electronic devices from damage caused by external shocks has become a key technical problem that needs to be solved urgently.

[0003] Among the many possible solutions, non-Newtonian fluid materials have attracted much attention due to their unique rate response characteristics. When encountering external forces, this type of material can show the unique performance of "strong when encountering strong forces and weak when encountering weak forces", which provides new ideas for the design of flexible impact-resistant materials. Among them, polyborosiloxane, as a typical non-Newtonian fluid material, has attracted people's attention due to its unique shear hardening properties since its advent in the 1940s. Companies such as the British D3O Laboratory and China Peak use polyborosiloxane and polyurethane to prepare composite materials and apply them to fields such as sports protection and adaptive soles. Driven by application needs, scientists have conducted a lot of research on polyborosiloxane in the past few decades and tried to improve its performance by constructing different single boron oxygen structures, but the impact resistance of this type of material has never been significantly improved. This limitation seriously restricts the widespread application of polyborosiloxane in harsh application scenarios, and also makes the development of new high-efficiency impact-resistant materials an urgent and arduous task. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the object of the present invention is to provide a composite material based on a polyborosiloxane interpenetrating polymer network and a preparation method and use thereof.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] The invention provides a composite material. The composite material is prepared by using a hydroxyl-terminated silicon matrix, tetrahydroxy diboron and a polymer as raw materials; the mass ratio of the hydroxyl-terminated silicon matrix, tetrahydroxy diboron and the polymer is 100:(0.1-15):(0.1-20).

[0007] Furthermore, the mass ratio of the terminal hydroxyl silicon substrate, tetrahydroxy diboron and polymer is 100:(1.255-6.094):(0.5-10) 。

[0008] Furthermore, the mass ratio of the terminal hydroxyl silicon substrate, tetrahydroxy diboron and polymer is 100:1.510:1, 100:2.019:2 or 100:3.547:5 。

[0009] Furthermore, the hydroxyl-terminated silicon matrix is ​​hydroxyl-terminated silicone oil, and the polymer is a synthetic polymer, a natural polymer or a natural polymer derivative.

[0010] Furthermore, the terminal hydroxyl silicone oil is dihydroxy silicone oil; the synthetic polymer is polyvinyl alcohol, polyethylene glycol, polylactic acid, polyvinyl pyrrolidone, polyacrylamide or polymethyl methacrylate; the natural polymer is konjac glucomannan, pectin, agar, sodium alginate, chitosan or starch; the natural polymer derivative is methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl starch, carboxymethyl starch, carboxylated chitosan or carboxymethyl cellulose.

[0011] Furthermore, the synthetic polymer is polyvinyl alcohol.

[0012] The present invention also provides a method for preparing the composite material, which comprises uniformly mixing a hydroxyl-terminated silicon matrix and a polymer, then adding tetrahydroxydiboron and reacting to obtain the composite material.

[0013] Furthermore, the mixing time is 0.1-2h; the reaction time is 5-15h; and the reaction temperature is 10-40°C.

[0014] Furthermore, the mixing time is 0.5 h; the reaction time is 8 h; and the reaction temperature is 25°C.

[0015] The present invention also provides use of the composite material in the fields of flexible electronic packaging and impact-resistant protective materials.

[0016] The present invention has achieved the following beneficial effects:

[0017] The present invention provides a composite material based on an interpenetrating polymer network of polyborosiloxane and a preparation method thereof, wherein polyborosiloxane is used as a matrix, and trace polymer components (polyvinyl pyrrolidone, polyvinyl alcohol, chitosan, etc.) are introduced, and multiple dynamic interactions between the boron hydroxyl groups of tetrahydroxydiborane and the doped molecular chains are utilized, namely, a synergistic crosslinking system including boron ester bonds, boron nitrogen coordination bonds, and boron oxygen coordination bonds is used to force the matrix to connect with the doped molecular chains to form an interpenetrating network, thereby significantly improving the mechanical properties and impact resistance of polyborosiloxane. The material has important application value in the fields of flexible electronic packaging and impact-resistant protective materials through dynamic bond chemical design and inorganic-organic hybrid structure innovation.

[0018] Obviously, according to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, other various forms of modification, replacement or change may be made.

[0019] The above contents of the present invention are further described in detail below through specific implementation methods in the form of embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples. All technologies realized based on the above contents of the present invention belong to the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the preparation process and molecular structure of polyborosiloxane (PDBS).

[0021] Figure 2 This is the infrared spectrum of the polyborosiloxane / polyvinyl alcohol composite material obtained in Example 1.

[0022] Figure 3 These are the small amplitude shear oscillation test results of the composite material obtained in Example 1-2.

[0023] Figure 4 1 is the stress-strain curve of the composite material obtained in Examples 1-4.

[0024] Figure 5 1 and 2 are stress-strain curves of the composite materials obtained in Examples 1 and 7-13.

[0025] Figure 6 These are the results of the falling ball impact test of polyborosiloxane / polyvinyl alcohol composites.

[0026] Figure 7 These are the test results of falling ball impact on composite materials obtained with different doped polymers. DETAILED DESCRIPTION

[0027] The raw materials and equipment used in the present invention are all known products, which are obtained by purchasing commercially available products.

[0028] The hydroxy silicone oil used in the specific embodiment, i.e. dihydroxy silicone oil, also known as dimethyl hydroxy silicone oil or hydroxyl-terminated polydimethylsiloxane, is a linear polymer with repeated silicon-oxygen bonds as the main chain, methyl groups as side groups and hydroxyl-terminated. It is purchased from Merrill, item number MER-DMS-S27-1KG, with a viscosity of 700-800 cSt and a molecular weight of 18,000.

[0029] The following experiments without any explanation of temperature are reactions under normal temperature conditions, where normal temperature is room temperature, which is 25±5℃.

[0030] The preparation process and molecular structure of polyborosiloxane (PDBS) are as follows: Figure 1 shown.

[0031] Example 1: Preparation of polyborosiloxane / polyvinyl alcohol composite material 1

[0032] The specific method is as follows: 10 g of hydroxy silicone oil (i.e., dihydroxy silicone oil) and 0.05 g of polyvinyl alcohol (molecular weight 58000) are added to a 100 ml beaker and stirred for 30 min at room temperature. Subsequently, 0.1255 g of tetrahydroxydiboron is added and stirred for 8 h to obtain a polyborosiloxane / polyvinyl alcohol composite material 1.

[0033] Example 2: Preparation of polyborosiloxane / polyvinyl alcohol composite material 2

[0034] Referring to the method of Example 1, the only difference is that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 is replaced by 0.1 g of polyvinyl alcohol (molecular weight 58,000), and 0.1255 g of tetrahydroxydiboron is replaced by 0.1510 g, to obtain a polyborosiloxane / polyvinyl alcohol composite material 2.

[0035] Example 3: Preparation of polyborosiloxane / polyvinyl alcohol composite material 3

[0036] Referring to the method of Example 1, the only difference is that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 is replaced by 0.2 g of polyvinyl alcohol (molecular weight 58,000), and 0.1255 g of tetrahydroxydiboron is replaced by 0.2019 g, to obtain a polyborosiloxane / polyvinyl alcohol composite material 3.

[0037] Example 4: Preparation of polyborosiloxane / polyvinyl alcohol composite material 4

[0038] Referring to the method of Example 1, the only difference is that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 is replaced by 0.5 g of polyvinyl alcohol (molecular weight 58,000), and 0.1255 g of tetrahydroxydiboron is replaced by 0.3547 g, to obtain a polyborosiloxane / polyvinyl alcohol composite material 4.

[0039] Example 5: Preparation of polyborosiloxane / polyvinyl alcohol composite material 5

[0040] Referring to the method of Example 1, the only difference is that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 is replaced by 0.8 g of polyvinyl alcohol (molecular weight 58,000), and 0.1255 g of tetrahydroxydiboron is replaced by 0.5075 g, to obtain a polyborosiloxane / polyvinyl alcohol composite material 5.

[0041] Example 6: Preparation of polyborosiloxane / polyvinyl alcohol composite material 6

[0042] Referring to the method of Example 1, the only difference is that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 is replaced by 1.0 g of polyvinyl alcohol (molecular weight 58,000), and 0.1255 g of tetrahydroxydiboron is replaced by 0.6094 g, to obtain a polyborosiloxane / polyvinyl alcohol composite material 6.

[0043] Example 7: Preparation of polyborosiloxane / polymethyl methacrylate composite material

[0044] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced by 0.05 g of polymethyl methacrylate (molecular weight 35,000), to obtain a polyborosiloxane / polymethyl methacrylate composite material.

[0045] Example 8: Preparation of polyborosiloxane / polyvinyl pyrrolidone composite material

[0046] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced by 0.05 g of polyvinyl pyrrolidone (molecular weight 130,000) to obtain a polyborosiloxane / polyvinyl pyrrolidone composite material.

[0047] Example 9: Preparation of polyborosiloxane / polyacrylamide composite material

[0048] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced by 0.05 g of polyacrylamide (molecular weight 2,000,000), to obtain a polyborosiloxane / polyacrylamide composite material.

[0049] Example 10: Preparation of polyborosiloxane / chitosan

[0050] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced by 0.05 g of chitosan (degree of deacetylation>95%, viscosity 100-200 mPa.s) to obtain a polyborosiloxane / chitosan composite material.

[0051] Example 11: Preparation of polyborosiloxane / carboxymethyl chitosan composite material

[0052] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced with 0.05 g of carboxymethyl chitosan (degree of substitution>85%, molecular weight 250,000-400,000) to obtain a polyborosiloxane / carboxymethyl chitosan composite material.

[0053] Example 12: Preparation of polyborosiloxane / soluble starch composite material

[0054] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced by 0.05 g of soluble starch to obtain a polyborosiloxane / soluble starch composite material.

[0055] Example 13: Preparation of polyborosiloxane / carboxymethyl cellulose composite material

[0056] The method of Example 1 was referred to, except that 0.05 g of polyvinyl alcohol (molecular weight 58,000) in Example 1 was replaced by 0.05 g of carboxymethyl cellulose (viscosity 300-800 mPa.s) to obtain a polyborosiloxane / carboxymethyl cellulose composite material.

[0057] The following is the preparation method of the control example.

[0058] Comparative Example 1: Preparation of polyborosiloxane

[0059] The specific method is as follows: 10 g of hydroxy silicone oil and 0.1 g of tetrahydroxydiboron are added into a 100 ml beaker, and stirred for 8 hours at room temperature to obtain polyborosiloxane.

[0060] The beneficial effects of the present invention are demonstrated by experimental examples below.

[0061] Experimental Example 1: Structural Characterization of Polyborosiloxane / Polyvinyl Alcohol Composites

[0062] The polyborosiloxane / polyvinyl alcohol composite material obtained in Example 1 was characterized by infrared spectroscopy. Figure 2 As shown, 3270 cm -1 The characteristic peak of stretching vibration of polyvinyl alcohol (PVA) hydroxyl group disappears near 1348cm -1The Si-OB characteristic peak appears nearby, indicating that the boron hydroxyl group of tetrahydroxydiboron successfully links the silicon-oxygen chain and the polymer chain.

[0063] Experimental Example 2: Small Amplitude Shear Oscillation Experiment

[0064] A small amplitude shear oscillation test was performed on the composite materials obtained in Example 1, Example 2 and Comparative Example 1. The specific method is as follows:

[0065] Rheological tests were conducted in accordance with GB / T 1681-2009, ISO 6721-10 and ASTM D6204 standards. The dynamic viscoelastic parameters (G', G") of the materials were determined using an Anton Paar MCR302 rheometer in torsional shear mode with a linear strain of 0.5%, a frequency range of 0.1-100 rad / s and a constant temperature of 25°C. The samples were disc specimens with a diameter of 8 mm and a thickness of 0.3-0.5 mm.

[0066] The results are as follows Figure 3 As shown in Table 1, the storage modulus of the composite materials obtained in Examples 1 and 2 are both higher than that of the composite material obtained in Comparative Example 1, and the storage modulus of the composite material obtained in Example 2 is higher than that of the composite material obtained in Example 1.

[0067] Table 1 Storage modulus of the composite material obtained in Examples 1-2 of the present invention

[0068] Composite Materials Storage modulus (Pa) Comparative Example 1 93668 Example 1 147570 Example 2 167480

[0069] Experimental Example 3: Tensile Test

[0070] (1) A tensile test was performed on the composite materials obtained in Examples 1-4 and Comparative Example 1. The specific method is as follows:

[0071] The tensile test is carried out according to the national standard GB / T 528-2009, using a SANSCMT4503 electronic universal testing machine (grade 1 accuracy). The specimen is a 4-type dumbbell (gauge length 20mm, width 2mm, thickness 0.3-0.5mm). After balancing in an environment of 23±2℃ / 50±5%RH for 24 hours, it is stretched at a rate of 100mm / min, and each group of valid data is ≥5. The entire test is clamped by a pneumatic clamp (preload force ≤1N), and force-displacement data (frequency ≥50Hz) are collected synchronously.

[0072] The stress-strain curves of the composite materials obtained in Examples 1-4 and Comparative Example 1 are as follows: Figure 4 As shown, the storage modulus and tensile strength are shown in Table 2, which are consistent with the rheological results. The elastic modulus of the composite material obtained in Comparative Example 1 is significantly lower than the composite materials obtained in Examples 1-4, and the composite material obtained in Example 4 has the highest elastic modulus and tensile strength.

[0073] Table 2 Elastic modulus and tensile strength of the composite materials obtained in Examples 1-4

[0074] Composite Materials Elastic modulus(Pa) Tensile strength(MPa) Comparative Example 1 19752 0.08 Example 1 36588 0.09 Example 2 36348 0.12 Example 3 38695 0.14 Example 4 53208 0.20

[0075] (2) Referring to the method of step (1), tensile tests were performed on the composite materials obtained in Examples 1, 7-13 and Comparative Example 1. The results are as follows: Figure 5 As shown in Table 3, the doped polymers in the embodiments of the present invention can improve the mechanical properties of polyborosiloxane, indicating that the doping of the polymer can significantly improve the elastic modulus and tensile strength of polyborosiloxane through cross-linking enhancement, interaction, filling effect and phase structure optimization. Among them, the elastic modulus of the composite material obtained in Example 13 is the best, and the tensile strength of the composite material obtained in Example 10 is the best.

[0076] Table 3 Elastic modulus and tensile strength of the composite materials obtained in Examples 1, 7-13

[0077] Composite Materials Elastic modulus(Pa) Tensile strength(MPa) Comparative Example 1 19752 0.08 Example 1 36588 0.09 Example 7 48007 0.09 Example 8 44180 0.18 Example 9 27989 0.17 Example 10 32358 0.23 Embodiment 11 18007 0.17 Example 12 16876 0.17 Embodiment 13 83633 0.20

[0078] Experimental Example 4: Drop ball impact test

[0079] The energy dissipation capacity of the composite materials obtained in Examples 1 to 13 of the present invention and Comparative Example 1 under different falling heights and ball masses was tested by a falling ball impact test to evaluate the impact resistance. The specific method is as follows:

[0080] According to GB / T 39814-2021, a steel ball is freely dropped to impact the specimen, and a force sensor is used to record the peak force and energy absorption. The specimen size is an 8mm diameter disc or rectangular sheet, and the thickness is usually 0.5mm. The specimen surface must be clean and free of scratches. The impact resistance is evaluated based on the peak force attenuation rate, which refers to the decrease in the maximum impact force (peak force) of the material under multiple impacts or different impact energies. where F 初始 is the peak force of the sensor without composite material covering, F 最终 is the peak force after the composite material covers the sensor. The experimental results of the composite materials obtained in Examples 1-6 are as follows Figure 6 As shown in Table 4, the peak force of a ball with the same mass (4.5 g) impacting the material at different heights (40 cm, 50 cm, and 60 cm, respectively) first decreases and then increases with the increase in the amount of polyvinyl alcohol, that is, the impact resistance first increases and then decreases. Among them, the impact resistance of the composite material obtained in Example 3 is the best.

[0081] Table 4 Impact resistance of the composite materials obtained in Examples 1-6

[0082]

[0083] The experimental results of the composite materials obtained in Examples 1 and 7-13 are as follows: Figure 7 As shown in Table 5, the force strength of different doped polymers at different heights (10 cm, 20 cm, and 30 cm) with the same falling ball mass (13.8 g) shows that polymer doping is beneficial to improving the impact resistance of polyborosiloxane. Among them, the composite material obtained in Example 7 has the best impact resistance.

[0084] Table 5 Impact resistance of the composite materials obtained in Examples 1, 7-13

[0085]

[0086] In summary, the present invention provides a composite material based on an interpenetrating polymer network of polyborosiloxane and a preparation method thereof, with polyborosiloxane as the matrix, by introducing trace polymer components (polyvinyl pyrrolidone, polyvinyl alcohol, chitosan, etc.), utilizing the multiple dynamic interactions between the boron hydroxyl groups of tetrahydroxydiborane and the doped molecular chains - a synergistic crosslinking system including boron ester bonds, boron nitrogen coordination bonds and boron oxygen coordination bonds, forcing the matrix to connect with the doped molecular chains to form an interpenetrating network, thereby achieving a significant improvement in the mechanical properties and impact resistance of polyborosiloxane. This material has important application value in the fields of flexible electronic packaging and impact-resistant protective materials through dynamic bond chemical design and inorganic-organic hybrid structure innovation.

Claims

1. A composite material, characterized in that: The composite material is prepared by using terminal hydroxyl silicon matrix, tetrahydroxy diboron and polymer as raw materials; the mass ratio of the terminal hydroxyl silicon matrix, tetrahydroxy diboron and polymer is 100:(0.1-15):(0.1-20).

2. The composite material according to claim 1, characterized in that: The mass ratio of the terminal hydroxyl silicon substrate, tetrahydroxy diboron and polymer is 100:(1.255-6.094):(0.5-10) 。 3. The composite material according to claim 2, characterized in that: The mass ratio of the terminal hydroxyl silicon substrate, tetrahydroxy diboron and polymer is 100:1.510:1, 100:2.019:2 or 100:3.547:5 。 4. The composite material according to any one of claims 1 to 3, characterized in that: The terminal hydroxyl silicon matrix is ​​terminal hydroxyl silicone oil, and the polymer is a synthetic polymer, a natural polymer or a natural polymer derivative.

5. The composite material according to claim 4, characterized in that: The terminal hydroxyl silicone oil is dihydroxy silicone oil; the synthetic polymer is polyvinyl alcohol, polyethylene glycol, polylactic acid, polyvinyl pyrrolidone, polyacrylamide or polymethyl methacrylate; the natural polymer is konjac glucomannan, pectin, agar, sodium alginate, chitosan or starch; the natural polymer derivative is methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl starch, carboxymethyl starch, carboxylated chitosan or carboxymethyl cellulose.

6. The composite material according to claim 5, characterized in that: The synthetic polymer is polyvinyl alcohol.

7. A method for preparing the composite material according to any one of claims 1 to 6, characterized in that: The method comprises the steps of uniformly mixing a terminal hydroxyl silicon matrix and a polymer, and then adding tetrahydroxydiboron to react to obtain the product.

8. The method according to claim 7, characterized in that: The mixing time is 0.1-2h; the reaction time is 5-15h; and the reaction temperature is 10-40°C.

9. The method according to claim 8, characterized in that: The mixing time is 0.5 h; the reaction time is 8 h; and the reaction temperature is 25°C.

10. Use of the composite material according to any one of claims 1 to 6 in the fields of flexible electronic packaging and impact-resistant protective materials.

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