Sticky rice mortar adhesive for masonry relics bonding by branched starch / inorganic / polymer composite

Abstract

The application discloses a branched starch / inorganic material / natural polymer composite waxy rice mortar adhesive for bonding masonry cultural relics, which is prepared from slaked lime, waxy rice mortar, hydroxypropyl methyl cellulose, clay and water in a certain mass ratio, wherein the mass concentration of the waxy rice mortar is 3-9%. The waxy rice mortar adhesive not only maximally retains the material quality and excellent bonding performance of ancient waxy rice mortar, but also greatly improves the flowability and viscoelasticity of the adhesive due to the addition of the hydroxypropyl methyl cellulose, so that the adhesive performance and tensile strength of the adhesive are improved. The adhesive can be applied not only to the repair of city wall masonry, but also to the bonding and repair of the fracture interface of earthenware cultural relics.

Description

Technical Field

[0001] This invention belongs to the field of natural organic / inorganic / polymer composite materials technology, specifically relating to an antique-style formula for glutinous rice mortar adhesive used to bond brick and stone cultural relics. Background Technology

[0002] With the emergence and advancement of composite tools in the Mesolithic period, matching joining technologies also appeared, with adhesives being one of the earliest and most widely used methods. In terms of material origin, ancient adhesives can be broadly categorized into animal glue, plant glue, and mineral glue. Among them, traditional Chinese mortar, represented by plant glue-glutinous rice mortar, had become a relatively mature technology during the Northern and Southern Dynasties. Ancient Chinese builders invented super-strong "glutinous rice mortar" by mixing glutinous rice soup with standard mortar. Scientists discovered glutinous rice components in the adhesive used to build the Great Wall of China (Ming Great Wall), and glutinous rice mortar is considered the main adhesive material of the Great Wall. This high-strength adhesive is also believed to be the reason why the Great Wall has stood for thousands of years. However, the ancient adhesive formulation and processing techniques have been lost for a long time, and the preparation methods are difficult to fully replicate. The underlying scientific mechanisms have not yet been fully revealed at the molecular level. In recent years, new chemical adhesives have been frequently used in cultural relic restoration. However, these new chemical adhesives can easily damage cultural relics. For example, epoxy-based chemical adhesives, once cured, have very high hardness. The adhesive penetrates into the substrate or crevices, making it difficult to remove and causing significant and irreversible damage to the substrate. Other acrylic-based chemical adhesives, due to their solvents, can cause discoloration of the cultural relic itself or the adhesive substrate, contaminating the adhesive. Based on these findings, experts in the field of cultural relic restoration are calling for adherence to the following principles: minimal intervention; reversibility or non-impact on future restoration; adding materials that are similar to or match the original materials, maintaining a balance between historical authenticity and aesthetic appeal; identifiability; safety and durability; and for immovable cultural relics, on-site preservation and restoration. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing adhesives used in the restoration of cultural relics, especially city walls, by providing a glutinous rice mortar adhesive with high fluidity and viscoelasticity, which is a composite of branched-chain starch, inorganic matter, and natural polymers. This adhesive can be applied not only to the restoration of bricks and stones in city walls but also to the bonding and repair of fractured interfaces in earthenware artifacts.

[0004] To achieve the above objectives, the glutinous rice mortar adhesive used in this invention is made from quicklime, glutinous rice paste, hydroxypropyl methylcellulose, clay, and water in a mass ratio of 100:65-150:1-4:50-200:50-200, wherein the mass concentration of the glutinous rice paste is 3%-9%.

[0005] Further preferred, the above-mentioned glutinous rice mortar adhesive is made from quicklime, glutinous rice paste, hydroxypropyl methylcellulose, clay, and water in a mass ratio of 100:80-85:2-3:100-150:50-100, wherein the mass concentration of glutinous rice paste is 7%-9%.

[0006] The aforementioned glutinous rice paste is prepared by mixing glutinous rice flour and water, and then cooking it in a 100°C water bath while stirring for 40–60 minutes. The glutinous rice flour is obtained by soaking long-grained, highly viscous indica glutinous rice in deionized water for 10–15 hours, followed by vacuum drying and grinding into powder in a grinder.

[0007] The clay mentioned above was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0008] The preparation method of the glutinous rice mortar adhesive of the present invention is as follows: quicklime is mixed with glutinous rice paste, clay and hydroxypropyl methylcellulose according to the mass ratio, and water is continuously added to make it evenly mixed. Then the mixture is placed on a magnetic stirrer and stirred for 40 to 90 minutes to obtain the glutinous rice mortar adhesive.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] 1. This invention simulates the ancient preparation process of glutinous rice mortar and develops a novel "glutinous rice mortar" adhesive composed of amylopectin-based compounds, inorganic substances, and natural polymers. Compared to traditional glutinous rice mortar, this adhesive removes sand and adds hydroxypropyl methylcellulose, which not only preserves the material properties and excellent bonding performance of ancient glutinous rice mortar to the greatest extent, but also greatly improves the fluidity and viscoelasticity of the adhesive by adding hydroxypropyl methylcellulose, thereby enhancing its adhesion and tensile strength.

[0011] 2. The components of the glutinous rice mortar adhesive of the present invention are low-cost, environmentally friendly and readily available materials. The preparation method is simple. It has properties such as high bonding strength, high shear strength and good fluidity. It can be applied not only to the repair of city wall bricks and stones, but also to the bonding and repair of fracture interfaces of earthenware cultural relics. Attached Figure Description

[0012] Figure 1 This is a comparison chart of the tensile strength of simulated samples after bonding the glutinous rice mortar adhesive prepared in Example 1 and the traditional glutinous rice mortar prepared in Comparative Example 1.

[0013] Figure 2 This is a viscosity comparison chart between the glutinous rice mortar adhesive prepared in Example 1 and the traditional glutinous rice mortar prepared in Comparative Example 1. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the scope of protection of the present invention is not limited to these embodiments.

[0015] Example 1

[0016] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring, before cooling to room temperature to obtain a glutinous rice paste with a mass concentration of 9%. Next, 10g of quicklime, 8.4g of the 9% glutinous rice paste, 0.2g of hydroxypropyl methylcellulose, 15g of clay, and 5g of water were weighed out. While mixing the quicklime with the rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0017] Example 2

[0018] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring, before cooling to room temperature to obtain a 3% (w / w) glutinous rice paste. Next, 10g of quicklime, 6.8g of the 3% (w / w) glutinous rice paste, 0.1g of hydroxypropyl methylcellulose, 5g of clay, and 8g of water were weighed out. While mixing the quicklime with the glutinous rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0019] Example 3

[0020] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring, before cooling to room temperature to obtain a glutinous rice paste with a mass concentration of 9%. Next, 10g of quicklime, 6.8g of the 9% glutinous rice paste, 0.4g of hydroxypropyl methylcellulose, 20g of clay, and 20g of water were weighed out. While mixing the quicklime with the rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0021] Example 4

[0022] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring. After cooling to room temperature, a 7% (w / w) glutinous rice paste was obtained. Next, 10g of quicklime, 10g of the 7% (w / w) glutinous rice paste, 0.4g of hydroxypropyl methylcellulose, 5g of clay, and 5g of water were weighed out. While mixing the quicklime with the glutinous rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0023] Example 5

[0024] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring, before cooling to room temperature to obtain a glutinous rice paste with a mass concentration of 9%. Next, 10g of quicklime, 11.6g of the 9% glutinous rice paste, 0.3g of hydroxypropyl methylcellulose, 5g of clay, and 10g of water were weighed out. While mixing the quicklime with the rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0025] Example 6

[0026] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring, before cooling to room temperature to obtain a 3% (w / w) glutinous rice paste. Next, 10g of quicklime, 13.2g of the 3% (w / w) glutinous rice paste, 0.3g of hydroxypropyl methylcellulose, 10g of clay, and 5g of water were weighed out. While mixing the quicklime with the glutinous rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0027] Example 7

[0028] First, glutinous rice was soaked in deionized water for 12 hours, then vacuum dried at 80℃ and ground into powder in a grinder. The rice powder was then mixed with water and cooked in a 100℃ water bath for 50 minutes while stirring, before cooling to room temperature to obtain a 5% (w / w) glutinous rice paste. Next, 10g of quicklime, 13.2g of the 5% (w / w) glutinous rice paste, 0.4g of hydroxypropyl methylcellulose, 15g of clay, and 8g of water were weighed out. While mixing the quicklime with the glutinous rice paste, clay, and hydroxypropyl methylcellulose, water was continuously added until the mixture was homogeneous. The mixture was then placed on a magnetic stirrer and stirred at a constant speed of 900 rpm for 1 hour to obtain a glutinous rice mortar adhesive. The clay was obtained from pits near the Terracotta Army of Qin Shi Huang.

[0029] Comparative Example 1

[0030] Mix 1g of lime, 2g of sand, 2g of red soil and 1g of glutinous rice paste with a mass concentration of 3% evenly, and then place the mixture on a magnetic stirrer and stir at a constant speed of 900r / min for 1h to obtain traditional glutinous rice mortar.

[0031] Two simulated samples with dimensions of 50mm × 15mm × 5mm were used. The simulated samples were bonded with the glutinous rice mortar adhesive prepared in Examples 1–7 and the traditional glutinous rice mortar prepared in Comparative Example 1, respectively. After the adhesive cured, the tensile strength was obtained by testing the force required for fracture using a universal testing machine, and the viscosity was tested in a rheometer. The test results are shown in Table 1 and [Table data would be inserted here]. Figures 1-2 .

[0032] Table 1. Distribution ratio and performance test results of each component of glutinous rice mortar adhesive.

[0033]

[0034] Note: The filler in the table is hydroxypropyl methylcellulose.

[0035] As shown in Table 1, the adhesive prepared by this invention exhibits superior tensile strength and adhesion performance. Figure 1 and Figure 2 It can be seen that the glutinous rice mortar adhesive prepared in Example 1 has higher bonding strength and better adhesion performance compared with the traditional glutinous rice mortar prepared in Comparative Example 1.

Claims

1. A branched-chain starch / inorganic material / polymer composite glutinous rice mortar adhesive for bonding brick and stone cultural relics, characterized in that: The glutinous rice mortar adhesive is made of slaked lime, glutinous rice paste, hydroxypropyl methyl cellulose, clay and water in a mass ratio of 100:65-85:1-3:50-150:50-100, wherein the mass concentration of the glutinous rice paste is 3%-9%, and the glutinous rice paste is prepared by mixing glutinous rice powder and water, and then boiling the mixture in a water bath at 100 DEG C for 40-60 minutes while stirring.

2. The amylopectin / inorganic / polymer composite glutinous rice mortar adhesive for bonding masonry cultural relics according to claim 1, characterized by: The glutinous rice mortar adhesive is made of slaked lime, glutinous rice paste, hydroxypropyl methyl cellulose, clay and water in a mass ratio of 100:80-85:2-3:100-150:50-100, wherein the mass concentration of the glutinous rice paste is 7%-9%.

3. The amylopectin / inorganic / polymer composite glutinous rice mortar adhesive for bonding masonry heritage according to claim 1, characterized by: The glutinous rice powder is obtained by soaking indica glutinous rice in deionized water for 10-15 hours, vacuum drying, and then grinding in a grinder to obtain powder.

4. The amylopectin / inorganic / polymer composite glutinous rice mortar adhesive for bonding masonry heritage according to claim 1, characterized by: The slaked lime is mixed with the glutinous rice paste, clay and hydroxypropyl methyl cellulose while continuously adding water, so as to be uniformly mixed, and then the mixture is stirred for 40-90 minutes to obtain the glutinous rice mortar adhesive.

Images