Hybrid pigment composite elastomer interface bonded anti-aging runway surface layer material and preparation method thereof

Abstract

The invention belongs to the technical field of sports facility materials, and discloses a hybrid pigment composite elastomer interface bonded anti-aging runway surface layer material and a preparation method thereof. The hybrid pigment composite elastomer interface bonded anti-aging runway surface layer material comprises a component A and a component B in a mass ratio of 1: (0.5-2), the component A comprises a polyurethane elastomer; the component B is prepared from the following components in parts by weight: 5 to 15 parts of polyether polyol, 20 to 40 parts of bio-based resin polyol, 2 to 5 parts of hybrid pigment, 50 to 65 parts of filler and 0.005 to 20 parts of additive. The anti-aging runway surface layer material disclosed by the invention has good appearance stability, excellent elasticity, comfort, wear resistance, durability and anti-aging performance and excellent anti-skid performance, and can meet high-standard requirements of professional sports events on field performance; and a safe, comfortable and durable use environment can be provided for daily training and leisure sports.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of sports facility materials, and discloses an anti-aging runway surface layer material bonded by hybrid pigments and composite elastomers and a preparation method thereof. BACKGROUND

[0002] With the improvement of the national fitness consciousness and the vigorous development of the sports industry, the demand for plastic runways as the core sports facilities in schools, sports venues and the like continues to grow. The plastic runways provide an ideal competition and training environment for athletes and convenience for the public for daily fitness due to excellent elasticity, wear resistance, slip resistance and comfort. The structure of the plastic runway is usually composed of a base layer (such as cement or asphalt concrete), a buffer layer (a mixture of rubber particles and glue) and a runway surface layer material. Among them, the runway surface layer directly bears the climbing, friction and environmental factors of athletes, and its performance plays a decisive role in the safety, use experience and service life of the runway.

[0003] At present, polyurethane (PU) materials synthesized by taking petroleum-based polyether polyols as raw materials are widely used in runway surface layers due to their good comprehensive performance (such as high elasticity, wear resistance and slip resistance). Such materials can indeed meet most of the use requirements in the initial state. However, in actual application, especially when exposed to harsh outdoor environments for a long time, the problem of insufficient anti-aging performance is increasingly prominent. Under the long-term and repeated action of environmental factors such as ultraviolet (UV) radiation, heat, oxygen and humidity, the material will exhibit significant photo-oxidative aging and thermal-oxidative aging phenomena, which are specifically manifested as follows: (1) surface deterioration: the material surface is prone to lose gloss, powdering and degradation, losing the original texture and color; (2) poor color stability: the material is prone to discoloration and fading, affecting the aesthetics of the runway; (3) mechanical property decay: the key mechanical properties of the material such as elasticity, tensile strength and tear strength significantly decrease; (4) functional degradation: the slip resistance performance is weakened, the friction coefficient is reduced, and the cushioning and shock absorption effect is deteriorated. These aging problems not only seriously damage the appearance quality and use comfort of the runway, but also seriously reduce the safety performance of the runway, greatly shorten the effective service life of the runway, and cause the user to need more frequent maintenance or replacement, resulting in resource waste and economic burden.

[0004] Therefore, it has become a key technical problem to be solved in the field to develop a new environmentally friendly runway surface layer material with excellent weather resistance, anti-aging, anti-oxidation and mechanical properties to overcome the shortcomings of the existing runway surface layer, such as easy aging and short service life. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide an anti-aging runway surface layer material bonded by hybrid pigments and composite elastomers and a preparation method thereof.

[0006] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0007] In a first aspect, the present application provides an anti-aging runway surface layer material bonded by hybrid pigment composite elastomer interface, comprising A component and B component with a mass ratio of 1:(0.5-2); the A component comprises a polyurethane elastomer; the B component comprises components with the following weight fractions: polyether polyol 5-15 parts, bio-based resin polyol 20-40 parts, hybrid pigment 2-5 parts, filler 50-65 parts, and auxiliary agent 0.005-20 parts; the bio-based resin polyol in the B component comprises low-hydroxyl-value bio-based resin polyol and high-hydroxyl-value bio-based resin polyol with a mass ratio of (0.75-3):1; the low-hydroxyl-value bio-based resin polyol has a hydroxyl value of 118.5 mgKOH / g-171.5 mgKOH / g; and the high-hydroxyl-value bio-based resin polyol has a hydroxyl value of 276.8 mgKOH / g-445.1 mgKOH / g.

[0008] The present application can make the runway surface layer material have good appearance stability, excellent elasticity, comfort, wear resistance, durability, anti-aging performance, mechanical properties, and outstanding anti-skid performance by compounding the polyurethane elastomer, polyether polyol, bio-based resin polyol, hybrid pigment, filler, and auxiliary agent. Specifically, the bio-based resin polyol system used in the present application can produce a synergistic effect with other components, significantly improving the wear resistance and tear resistance of the surface layer material while maintaining high elasticity, so that the runway can withstand long-term use and friction from various sports activities, prolonging the service life. In addition, the bio-based resin polyol system can also improve the stability of polyurethane and enhance the ability of the mixed elastomer to resist acid, alkali, salt, and organic solvents by synergizing with other components, providing excellent toughness and elasticity to the material, making it perform better in terms of ultraviolet resistance and anti-aging, maintaining stable performance under different climate conditions, not easily fading or falling off due to factors such as friction, sun exposure, and rain, and maintaining a beautiful appearance for a long time, prolonging the service life. Furthermore, the roughness and friction coefficient of the material surface can be adjusted to give the runway good anti-skid performance, ensuring the safety of athletes during running, jumping, and other sports, not only meeting the high standard requirements of professional sports events for venue performance, but also providing a safe, comfortable, and durable use environment for daily training and leisure sports.

[0009] As a preferred embodiment of the anti-aging runway surface layer material bonded by hybrid pigment composite elastomer interface of the present application, the mass ratio of the low-functionality bio-based resin polyol to the high-functionality bio-based resin polyol is (1-2):1.

[0010] Preferably, the mass ratio of the low functionality bio-based resin polyol and the high functionality bio-based resin polyol is any one of 1:1, 1:1.25, 1:1.5, 1:1.75, 1:2 or a range value of two of them.

[0011] As a preferred embodiment of the anti-aging runway surface layer material of the hybrid pigment composite elastomer interfacial bonding of the present application, the low hydroxyl value bio-based resin polyol has a hydroxyl value of 155.3 mgKOH / g; the high hydroxyl value bio-based resin polyol has a hydroxyl value of 322.4 mgKOH / g.

[0012] As a preferred embodiment of the anti-aging runway surface layer material of the hybrid pigment composite elastomer interfacial bonding of the present application, the polyurethane elastomer is prepared by polyether polyol, bio-based resin polyol and isocyanate reaction.

[0013] Preferably, the mass ratio of the polyether polyol, bio-based resin polyol and isocyanate is (2.5-6):(1.5-4):1.

[0014] Preferably, the polyether polyol includes a polyether polyol with a hydroxyl value of 34.5 mgKOH / g and a polyether polyol with a hydroxyl value of 56.3 mgKOH / g.

[0015] Preferably, the bio-based resin polyol has a hydroxyl value of 155.3 mgKOH / g.

[0016] Preferably, the isocyanate is diphenylmethane diisocyanate.

[0017] Preferably, the reaction temperature is 70-90°C.

[0018] As a preferred embodiment of the anti-aging runway surface layer material of the hybrid pigment composite elastomer interfacial bonding of the present application, the polyether polyol has a hydroxyl value of 50-75 mgKOH / g.

[0019] Preferably, the polyether polyol has a hydroxyl value of 56.3 mgKOH / g.

[0020] As a preferred embodiment of the anti-aging runway surface layer material of the hybrid pigment composite elastomer interfacial bonding of the present application, the auxiliary agent includes the following components in parts by weight: plasticizer 5-10 parts, interfacial bonding agent 0.5-1 part, defoaming agent 0.005-0.2 part, dispersing agent 0.05-0.2 part, catalyst 0.1-0.3 part, antioxidant 0.4-0.8 part, ultraviolet absorber 0.4-0.8 part, water removal agent 0.5-1 part.

[0021] In a second aspect, the present application provides a preparation method of the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface, comprising the following steps:

[0022] (1) The bio-based resin polyol, polyether polyol, hybrid pigment and filler are mixed and heated to 90-105 DEG C, and then vacuum dried for 2-2.5 h; the temperature is lowered to 50-65 DEG C, and the auxiliary agent is added and uniformly mixed to obtain the B component;

[0023] (2) The A component and the B component are uniformly mixed to obtain the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface.

[0024] In a third aspect, the present application provides a plastic runway comprising the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface.

[0025] Compared with the prior art, the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface has the following beneficial effects: the bio-based resin polyol with low and high hydroxyl value is scientifically proportioned, and is synergized with polyether polyol, hybrid pigment, filler and auxiliary agent and other key components to significantly improve the performance of the material. On the one hand, the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface has excellent appearance stability, and the color is bright and durable, and the anti-aging performance is excellent, and the appearance stability can be maintained for a long time; on the other hand, the material has excellent elasticity, comfort, wear resistance and weather resistance, can effectively buffer the impact force and provide stable support, can provide good foot feeling and buffering for athletes, reduce sports injuries, and ensure that the runway maintains stable performance under long-term use and different weather conditions. In addition, the excellent wear resistance and durability of the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface ensure that the runway remains smooth and intact under high frequency use, prolonging the service life. At the same time, the introduction of bio-based resin polyol not only improves the comprehensive performance of the material, but also meets the sustainable development concept, so that the surface layer material becomes an ideal choice for modern sports facility construction. In addition, the preparation method of the anti-aging runway surface layer material bonded by the hybrid pigment composite elastomer interface does not require special process and equipment, is simple to operate, can realize industrialized production, and meets the large-scale processing demand. DETAILED DESCRIPTION

[0026] In order to better illustrate the purposes, technical solutions and advantages of the present application, the present application will be further described below in combination with specific examples. Those skilled in the art should understand that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0027] The following specific examples are described to illustrate the actual effect of the present application.

[0028] The test methods used in the examples are conventional methods unless otherwise specified; the materials, reagents, equipment, etc. used are commercially available unless otherwise specified.

[0029] The raw materials used in the following examples and comparative examples are described below, but are not limited to these materials:

[0030] The hydroxyl value of the following polyols is tested according to GB / T 12008.3-2009 standard.

[0031] Table 1: Manufacturer information of raw materials

[0032]

[0033] Example 1:

[0034] The present embodiment provides a polyurethane runway surface material, which comprises A component and B component, and the mixing ratio of A component and B component is 1:1.

[0035] (1) The raw materials of A component include the following components in parts by weight: F3135 polyether polyol 25 parts, C2020 polyether polyol 15 parts, L140 bio-based resin polyol 10 parts, 52# long-chain chlorinated paraffin 15 parts, diphenyl methane diisocyanate 25 parts.

[0036] The preparation method of A component includes the following steps:

[0037] (a) F3135 polyether polyol, C2020 polyether polyol, L140 bio-based resin polyol, 52# long-chain chlorinated paraffin are added into the reaction kettle and stirred uniformly, then the material in the reaction kettle is heated to 100℃, and vacuum dehydration is carried out under the condition of vacuum pressure-0.08MPa for 2h, and then the vacuum is stopped.

[0038] (b) The temperature of the material in the reaction kettle is reduced to 90℃, and diphenyl methane diisocyanate is added, and the temperature is adjusted to 80℃, and constant temperature reaction is carried out for 2.5 hours, to prepare the runway surface material A component, which is stored at room temperature.

[0039] (2) The raw materials of B component include the following components in parts by weight: L140 bio-based resin polyol 15 parts, L320 bio-based resin polyol 10 parts, C2020 polyether polyol 10 parts, 52# long-chain chlorinated paraffin 5 parts, phthalo blue and peptide white powder hybrid color paste 4 parts, heavy calcium carbonate filler 53.7 parts, LC-2120 interface bonding agent 0.5 parts, B90 antioxidant 0.5 parts, 1050N ultraviolet absorber 0.5 parts, BAT-2800 non-silicon defoamer 0.05 parts, BAT-5104L dispersant 0.1 parts, organic zinc and organic bismuth (1:3 mixed) catalyst 0.15 parts, molecular sieve activated powder water removal agent 0.5 parts.

[0040] The preparation method of the B component comprises the following steps:

[0041] (a) L140 bio-based resin polyol, L320 bio-based resin polyol, C2020 polyether polyol, 52# long-chain chlorinated paraffin, high-grade phthalo blue and peptide white powder hybrid color paste, heavy calcium carbonate are added into a reaction kettle for high-speed dispersion and uniformity;

[0042] (b) The material in the reaction kettle is heated to 100°C, and vacuum dehydration is carried out under the condition that the vacuum pressure is-0.08 MPa for 2 h, and the vacuum is stopped.

[0043] (c) The material in the reaction kettle is cooled to 60°C, LC-2120 interface bonding agent, B90 antioxidant, 1050N ultraviolet absorber, BAT-2800 non-silicon defoamer, BAT-5104L dispersant, organic zinc and organic bismuth (1:3 mixture) catalyst, and molecular sieve activated powder water removal agent are added, and stirring is carried out for 30 minutes until the material is uniformly dispersed, so that the runway surface layer material B component is prepared, and the obtained product is sealed and stored at room temperature.

[0044] Example 2:

[0045] The difference between the polyurethane runway surface layer material of the present embodiment and that of example 1 is that:

[0046] The raw materials of the A component include the following components in parts by weight: F3135 polyether polyol 30 parts, C2020 polyether polyol 20 parts, L140 bio-based resin polyol 5 parts, 52# long-chain chlorinated paraffin 10 parts, and diphenyl methane diisocyanate 30 parts.

[0047] Example 3:

[0048] The difference between the polyurethane runway surface layer material of the present embodiment and that of example 1 is that:

[0049] The raw materials of the B component include the following components in parts by weight: L140 bio-based resin polyol 7.5 parts, L320 bio-based resin polyol 10 parts, C2020 polyether polyol 5 parts, 52# long-chain chlorinated paraffin 5 parts, phthalo blue and peptide white powder hybrid color paste 2 parts, heavy calcium carbonate filler 50 parts, LC-2120 interface bonding agent 0.5 parts, B90 antioxidant 0.4 parts, 1050N ultraviolet absorber 0.4 parts, BAT-2800 non-silicon defoamer 0.005 parts, BAT-5104L dispersant 0.05 parts, organic zinc and organic bismuth (1:3 mixture) catalyst 0.1 parts, and molecular sieve activated powder water removal agent 0.5 parts.

[0050] Example 4:

[0051] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the raw materials of the B component include the following components in parts by weight: L140 bio-based resin polyol 30 parts, L320 bio-based resin polyol 10 parts, C2020 polyether polyol 15 parts, 52# long-chain chlorinated paraffin 10 parts, phthalocyanine blue and peptide white powder hybrid color paste 5 parts, heavy calcium carbonate filler 65 parts, LC-2120 interface bonding agent 1 part, B90 antioxidant 0.8 part, 1050N ultraviolet absorber 0.8 part, BAT-2800 non-silicon defoamer 0.2 part, BAT-5104L dispersant 0.2 part, organic zinc and organic bismuth (1:3 mixture) catalyst 0.3 part, and molecular sieve activated powder water remover 1 part.

[0052] Embodiment 5:

[0053] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the L140 bio-based resin polyol 15 parts in the raw materials of the B component is replaced by L140 bio-based resin polyol 10 parts.

[0054] Embodiment 6:

[0055] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the L140 bio-based resin polyol 15 parts in the raw materials of the B component is replaced by L140 bio-based resin polyol 20 parts.

[0056] Embodiment 7:

[0057] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the L140 bio-based resin polyol in the raw materials of the B component is replaced by an equal amount of L120 bio-based resin polyol.

[0058] Embodiment 8:

[0059] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the L140 bio-based resin polyol in the raw materials of the B component is replaced by an equal amount of L170 bio-based resin polyol.

[0060] Embodiment 9:

[0061] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the L320 bio-based resin polyol in the raw materials of the B component is replaced by an equal amount of L270 bio-based resin polyol.

[0062] Embodiment 10:

[0063] The difference between the polyurethane runway surface layer material of the present embodiment and that of embodiment 1 is that the L320 bio-based resin polyol in the raw materials of the B component is replaced by an equal amount of L450 bio-based resin polyol.

[0064] Comparative Example 1:

[0065] The difference between this example and the polyurethane runway surface layer material of Example 1 is that the L140 bio-based resin polyol 15 parts and L320 bio-based resin polyol 10 parts in the raw materials of B component are replaced by F3135 polyether polyol 15 parts and C2020 polyether polyol 10 parts; and the phthalocyanine blue and peptide white powder hybrid color paste is replaced by an equal amount of ordinary blue powder.

[0066] Comparative Example 2:

[0067] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L140 bio-based resin polyol in the raw materials of A component is replaced by an equal amount of C2020 polyether polyol.

[0068] Comparative Example 3:

[0069] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L140 bio-based resin polyol is not included in the raw materials of B component.

[0070] Comparative Example 4:

[0071] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L320 bio-based resin polyol is not included in the raw materials of B component.

[0072] Comparative Example 5:

[0073] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L140 bio-based resin polyol in the raw materials of B component is replaced by an equal amount of F3135 polyether polyol.

[0074] Comparative Example 6:

[0075] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L320 bio-based resin polyol in the raw materials of B component is replaced by an equal amount of C2020 polyether polyol.

[0076] Comparative Example 7:

[0077] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L320 bio-based resin polyol 10 parts in the raw materials of B component is replaced by L320 bio-based resin polyol 30 parts.

[0078] Comparative Example 8:

[0079] The difference between this comparative example and the polyurethane runway surface layer material of Example 1 is that the L320 bio-based resin polyol 15 parts in the raw materials of B component is replaced by L320 bio-based resin polyol 50 parts.

[0080] Test example:

[0081] The runway surface paint A component and the B component of the above examples and the comparative examples were mixed at a mass ratio of 1:1 under normal temperature conditions, and stirred uniformly, the AB component mixture was poured into a mold to make a sample plate with a width of 30 cm, a length of 40 cm and a thickness of 0.3 cm, and the sample plate was cured and maintained for 7 days before performance testing.

[0082] (1) The viscosity of the mixture was determined by referring to GBT9751.1-2008 with a rotary viscometer (NDJ-1 rotary viscometer).

[0083] (2) The tensile strength and elongation at break were determined according to the requirements of 6.4 of GB36246-2018 (FBS-500N liquid crystal display electronic universal testing machine), and the method was recorded according to the method specified in GB / T10654-2001.

[0084] (3) The determination requirements of the aging resistance performance were referred to 6.9 of GB36246-2018, and the xenon lamp irradiation test was carried out according to the provisions of GB / T16422.2-2014 (HT-XO-150 xenon lamp aging test box), the test conditions were method A and cycle number 1, after 500h of testing, the tensile strength and elongation at break were determined according to the method specified in 6.4, and visual colorimetry was carried out under natural sunlight according to GB 9761-2008.

[0085] The results are shown in Table 2.

[0086] Table 2: Performance test results

[0087]

[0088]

[0089] From the data in the table, it can be seen that the runway sample plate prepared from the polyurethane runway surface layer material of the examples of the present application with specific content of components shows better thermal stability and aging resistance after 500 hours of xenon lamp aging machine test, and the toughness and strength of the material are improved, the bio-based polyol is abundant in source and belongs to renewable and environmentally friendly resources; in addition, the present application does not add solvent, has low viscosity, and has the advantages of environmental protection and easy construction.

[0090] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit the protection scope of the present application, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the essence and scope of the technical solutions of the present application.

Claims

1. A hybrid pigment composite elastomer interfacial bonded anti-aging runway surface material, characterized in that, The product comprises component A and component B in a mass ratio of 1:(0.5-2); component A comprises polyurethane elastomer; component B comprises the following components in parts by weight: 5-15 parts polyether polyol, 20-40 parts bio-based resin polyol, 2-5 parts hybrid pigment, 50-65 parts filler, and 0.005-20 parts additives; the bio-based resin polyol in component B comprises low-hydroxyl-value bio-based resin polyol and high-hydroxyl-value bio-based resin polyol in a mass ratio of (0.75-3):1; the low-hydroxyl-value bio-based resin polyol has a hydroxyl value of 118.5 mgKOH / g-171.5 mgKOH / g; and the high-hydroxyl-value bio-based resin polyol has a hydroxyl value of 276.8 mgKOH / g-445.1 mgKOH / g.

2. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 1, characterized in that, The mass ratio of the low hydroxyl value bio-based resin polyol to the high hydroxyl value bio-based resin polyol is (1-2):

1.

3. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 1, characterized in that, The low hydroxyl value bio-based resin polyol has a hydroxyl value of 155.3 mg KOH / g; the high hydroxyl value bio-based resin polyol has a hydroxyl value of 322.4 mg KOH / g.

4. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 1, characterized in that, The polyurethane elastomer is prepared by reacting polyether polyol, bio-based resin polyol and isocyanate.

5. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 4, characterized in that, The mass ratio of the polyether polyol, bio-based resin polyol, and isocyanate is (2.5-6):(1.5-4):

1.

6. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 4, characterized in that, The reaction temperature is 70℃-90℃.

7. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 1, characterized in that, The hydroxyl value of the polyether polyol is 50 mg KOH / g-75 mg KOH / g.

8. The anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomer as described in claim 1, characterized in that, The additives comprise the following components in parts by weight: 5-10 parts plasticizer, 0.5-1 part interfacial bonding agent, 0.005-0.2 parts defoamer, 0.05-0.2 parts dispersant, 0.1-0.3 parts catalyst, 0.4-0.8 parts antioxidant, 0.4-0.8 parts ultraviolet absorber, and 0.5-1 part dehydrating agent.

9. A method for preparing an anti-aging runway surface material with interfacial bonding of hybrid pigment composite elastomers as described in any one of claims 1-8, characterized in that, Includes the following steps: (1) Mix the bio-based resin polyol, polyether polyol, hybrid pigment and filler and heat to 90℃-105℃, then vacuum dry for 2h-2.5h, cool to 50℃-65℃, add the additive and mix evenly to obtain component B. (2) Mix the A component and the B component evenly to obtain the anti-aging runway surface material with interfacial bonding of the hybrid pigment composite elastomer.

10. A type of plastic running track, characterized in that, The anti-aging runway surface material includes the hybrid pigment composite elastomer interfacial bonded material as described in any one of claims 1-8.

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